R E M O D E L I N G T H E P A S T F O R A R E S I L I E N T F U T U R E Fault Lines The Mexico City Earthquakes of 1985 and 2017 p16 Constructing Resilience: The 2010 Earthquakes in Haiti and Chile p38 ACKNOWLEDGMENTS This publication was prepared by a team led by Emma Phillips and comprising Stuart Fraser, Richard Murnane, and Nick Paul, of the Global Facility for Disaster Reduction and Recovery (GFDRR), and by Kerri Cox, James Daniell, Rashmin Gunasekera, Oscar Ishizawa, Xijie Lu, Antonios Pomonis, and Julia Saenz Ortigosa, of the World Bank Disaster- Resilience Analytics and Solutions (D-RAS) Knowledge Silo Breaker (KSB) team. The team drew from scenarios developed by D-RAS KSB for Armenia (1988 Spitak earthquake), Chile (2010 Maule earthquake), Dominican Republic (1930 San Zenon hurricane), Haiti (2010 earthquake), Madagascar (2017 Tropical Cyclone Enawo), and Indonesia (1815 Tambora volcano eruption). The team would like to thank Daniel Raisman and Roger Grenier of AIR Worldwide, Eduardo Reinoso of Evaluación de Riesgos Naturales (ERN), © 2018 Global Facility for Disaster Reduction and Recovery / The World Bank and Iain Willis of JBA Consulting for their technical contributions on 1818 H Street, N.W., Washington, D.C., 20433, U.S.A. China (Typhoon Wanda), Mexico (1985 Mexico City earthquake), and Telephone: 202 473 1000 Thailand (2011 Thailand floods), respectively. Internet: www.worldbank.org This work is a product of the staff of The World Bank and GFDRR with external contributions. The findings, We would like to thank Nicolas Pondard and Mathijs Van Ledden of analysis and conclusions expressed in this document do not necessarily reflect the views of any individual partner GFDRR for their valuable technical input. organization of The World Bank, its Board of Directors, or the governments they represent. This publication also benefited from inputs and advice from the following Although GFDRR makes reasonable efforts to ensure all the information presented in this document is correct, its GFDRR and World Bank colleagues: Gabriela Aguilar, Cristoba Mena accuracy and integrity cannot be guaranteed. Use of any data or information from this document is at the user’s own Amigo, Simone Balog-Way, Ana Luna Barros, Eduardo Ereno Blanchet, risk and under no circumstances shall GFDRR or any of its partners be liable for any loss, damage, liability or expense Roland Bradshaw, Manuela Chiapparino, Tafadzwa Dube, Joan Dessaint incurred or suffered which is claimed to result from reliance Fomi, Abhas Jha, Brenden Jongman, Jolanta Kryspin-Watson, Liliana on the data contained in this document. The boundaries, colors, denomination, and other information shown in any Lopez-Ortiz, Michel Matera, Rolande Simone Pryce, Taimur Samad, map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory Vigen Sargsyan, Kristyn Schrader-King, Tuo Shi, Alanna Simpson, or the endorsement or acceptance of such boundaries. Joaquin Toro, and Jocelyn West. RIGHTS AND PERMISSIONS The material in this work is subject to copyright. Because Anne Himmelfarb provided editing services. Miki Fernandez and Fiorella The World Bank encourages dissemination of its knowledge, this work may be reproduced, in whole or in Gil designed the document, and Axis Maps provided final versions of the part, for noncommercial purposes as long as full attribution to this work is given. Any queries on rights and licenses, maps. including subsidiary rights, should be addressed to the Office of the Publisher, The World Bank, 1818 H Street NW, Washington, DC 20433, USA; fax: 202-522-2422; e-mail: Finally, particular thanks go to Francis Ghesquiere, Head of the GFDRR pubrights@worldbank.org. Secretariat, who provided the initial inspiration and concept for the GFDRR’s Secretariat would appreciate receiving a copy of any publication that uses this report as a source. Copies report. may be sent to the Secretariat at the above address. No use of this publication may be made for resale or other commercial purpose without prior written consent of the Secretariat. All images remain the sole property of the source and may not be used for any purpose without written permission from the source. CONTENTS Foreword p3 Overview p5 Fault Lines: The Mexico City Earthquakes of 1985 and 2017 p16 Shadow of the Past: Mount Tambora, Indonesia, 1815 p22 The Power of Hindsight: What If Vesuvius Erupted Today? p6 The Lessons of Vulnerability: Spitak Earthquake, 1988 p30 A Fragile Harvest: Tropical Cyclone Enawo, Madagascar, 2017 p34 Constructing Resilience: The 2010 Earthquakes in Haiti and Chile p38 A Direct Hit: San Zenon Hurricane, Santo Domingo, 1930 p44 When the Rivers Rise: Thailand Floods, 2011 p48 Building on Experience: The Scary Wind: Typhoon Wanda, Zhejiang, China, 1956 p52 Risk Modeling p12 Return of the Black Swan: The Carrington Event, 1859 p56 Modeling the Future: From Statistics to Stories to Action p60 Bibliography p63 Abbreviations and Acronyms p64 “THE PAST IS NEVER DEAD. IT’S NOT EVEN PAST.” —William Faulkner FOREWORD With the words of Faulkner in mind, flares on a scale of the Carrington As the world’s population continues we might argue that the disasters of event of 1859—could have to grow, and to urbanize, so too the past are not past, as long as they tremendous consequences if they does its exposure and vulnerability have something to teach us. happened in today’s exponentially to hazards. With climate change, more populous and connected some of the hazards we face are The Global Facility for Disaster world, with massive loss of life and also becoming more frequent, more Reduction and Recovery (GFDRR) major disruptions to transport, intense, and more unpredictable; conceived of this publication as communications, and commerce. and the combination of these factors a thought exercise: what would As the 2011 Tohoku earthquake the effects be if some of the has the potential to increase risk and tsunami demonstrate, events exponentially. The scenarios in iconic disaster events of the past of this scale will always be with this publication remind us of the were to happen in today’s world? us. Modeling helps us imagine the How have our actions mitigated urgency of integrating better risk potential impact of such events. or exacerbated their potential management and climate adaptation Most of the disasters you will impacts? What if Mount Vesuvius in all development programs. read about are comparatively erupted today, close to the heart By fostering resilience through recent—like the earthquake in of a modern European city? Or if measures like improved building Mexico City on September 19, 2017, Typhoon Wanda, which hit Zhejiang practices, better land use planning, which struck on the anniversary Province in China in 1956, were and poverty reduction, we can of the far more devastating 1985 to strike again in the same area— strive to reduce the vulnerability of earthquake. The reanalysis of such now home to the world’s third infrastructure and communities. events creates an opportunity biggest conurbation, and more to disentangle cause and effect, I personally would like to thank than 50 million people? To answer providing essential information for the team that led the work on this these questions, we turned to risk future mitigation strategies. modeling. publication, as well as the partners Disasters are of course inherently who provided the model results Risk modeling distills earth sciences used. The Disaster-Resilience challenging to model, with and technical knowledge into Analytics and Solutions (D-RAS) uncertainties in what determines analysis of the potential impacts of the probability of extreme events, team of the World Bank provided adverse natural events, expressed and the need to understand all the risk model results for six of the in terms of casualties, damage potential causes and weaknesses case studies we drew upon, and to assets and infrastructure, or leading to the losses. The challenges colleagues from AIR Worldwide, monetary loss. It is not an exact of risk modeling are great, but the ERN, and JBA Consulting provided science, but when thorough and rewards are significant. It provides information on some of the other based on sound assumptions and valuable input in diverse areas, disasters modeled. analysis, it can provide useful from the establishment of early insights and direction for action. The past can be a powerful tool. As warning systems to urban planning, Within this framework, scenario from preparedness to financial the stories you will read in these studies that reexamine possible protection and better recovery. It pages demonstrate, we need to consequences of past disasters can produces risk information that may learn its lessons, and apply them help guide interventions to address be used across multiple sectors, to plans for a better, more resilient problematic development patterns. from global supply chains to small- future. Some of the events examined in scale local agriculture, as examples these pages—for example, the 1815 from Thailand and Madagascar Francis Ghesquiere eruption of Mount Tambora, or solar respectively illustrate. Head, GFDRR Secretariat Aftershocks 3 Mexico City, 2012. Photo: ESA OVERVIEW Aftershocks aims to provide benefits of building back better audience and community of readers with an accessible look at after a disaster by analyzing the practice. However, reporting in what would happen today if we impact of improved building code this publication is by no means were to experience some of the enforcement and resilient urban comprehensive, and readers who iconic disasters of the past. The planning to mitigate the impact of prefer greater detail or a more pages that follow look at how risk future events. The damage from technical account of the events modeling can be used to analyze Typhoon Wanda demonstrates described can consult the risk natural events that led to the both the impact of natural hazards profiles and detailed analyses that major disasters of the past, and to on a rapidly growing economy are linked to the online version. understand how these events might and the benefits of effective risk Readers are also directed to the impact today’s more populous and identification and early warning bibliography (p. 63). connected world. systems. The two earthquakes in Mexico City illustrate the Most of the disasters documented The events included in this importance of integrating multiple here happened in the recent publication were selected to areas of risk management, from risk past. Adverse natural events of a represent a range of regions and identification and preparedness to significant magnitude happen all hazards, and to illustrate the civil and financial protection. the time, and will happen again. evolution of exposure and how By 2050, population growth and vulnerability translates into risk. Most of the disasters documented rapid urbanization could put 1.3 They were also chosen to illustrate here took place in the developing billion people and $158 trillion1 in the impacts of disasters on a range world, where population growth, assets at risk from river and coastal of sectors, including agriculture, rapid urbanization, and climate floods alone2—a reminder that the infrastructure, the supply chain, change are heightened, and where integration of risk management in and—in the case of the Carrington the impact of adverse events is our development programs is an event—the vulnerable “digital exacerbated by the vulnerability urgent imperative. cocoon” in which we have encased of poorer communities, who are the world. Finally, the events were disproportionately impacted by chosen to highlight diverse areas disasters. This report makes the of engagement in disaster risk case for renewed support to the management. poorest of the poor. The case studies of the This report is also part of an 1 All dollar amounts in this report refer earthquakes in both Chile and effort to bring about a better to U.S. dollars. Haiti, for example, show the understanding of risk to a wider 2 Jongman, Ward, and Aerts 2012. Aftershocks 5 The Last Days of Pompeii by Karl Bryullov, 1830–1833. Image: Wikipedia THE POWER OF HINDSIGHT What If Vesuvius Erupted Today? The eruption of Vesuvius in 79 AD destroyed two cities, claimed at least 1,500 lives, and left a vivid snapshot of a past disaster for posterity. What if the volcano erupted today, in an urbanized and connected world? Risk modeling can help assess the likely losses and guide actions that might mitigate the risk. Aftershocks 7 8 Aftershocks It is estimated that “You might hear the shrieks of women, the screams of children, the eruption at times and the shouts of men; some produced a column of calling for their children, others ash 32 km tall, for their parents, others for and that about their husbands, and seeking to recognize each other by 4 km3 of ash was the voices that replied; one erupted in about lamenting his own fate, another 19 hours. that of his family; some wishing to die, from the very fear of dying; some lifting their hands to the gods; but the greater part convinced that there were now no gods at all, and that the final endless night of which we have heard had come upon the world.” —Pliny the Younger, on the eruption of Vesuvius For a disaster that happened almost 2,000 years ago, the tragedy Ash-encapsulated remains of some of the still seems fresh and poignant. The victims of the Vesuvius eruption of 79 AD. figures of Pompeiians preserved Photo: © Floriano Rescigno | Dreamstime.com in volcanic ash—working people, Facing page: Aerial view of Mount Vesuvius with densely populated communities families with children, even surrounding it. Photo: © DigitalGlobe household pets—are evidence that things were not so very different then. The buildings, the preserved the emperor Nero, had written artifacts, and the murals all show on the causes of earthquakes in The volcanoes monitored by the Vesuvius Observatory a perfectly ordinary Roman town his Naturales quaestiones. He going about its business on a thought it likely that earthquakes day like any other, oblivious to in different parts of the world were the impending cataclysm, and interconnected, and even wrongly unprepared for disaster. suggested that they were linked to stormy weather, but he drew no Phlegraean Fields This lack of preparedness was link with volcanic activity. Pliny the Vesuvius not due to lack of interest in the Younger experienced the eruption Ischia natural world and its processes. of Vesuvius and wrote an account Stromboli Fifteen years before the eruption of the death of his uncle—Pliny the of Mount Vesuvius in 79 AD, the Elder—in the eruption. Pliny the philosopher Seneca, advisor to Elder had himself been the most Aftershocks 9 Monitoring room of the Vesuvius Observatory in Naples. The observatory monitors the activity of all the Campanian volcanoes (Ischia, Vesuvius, and the Phlegraean Fields, as well as Stromboli). Photo: Salvatore Laporta/KONTROLAB /LightRocket via Getty Images. The Vesuvius notable scientist and naturalist of the manner I have mentioned; Observatory, founded his age, but he had failed to see it appeared sometimes bright the significance of seismic activity and sometimes dark and spotted, in 1841 on the in the weeks leading up to the according as it was either more slopes of the volcano eruption. or less impregnated with earth but now situated and cinders. The younger Pliny’s descriptions in Naples, is the of the eruption in the two letters It is estimated that the eruption oldest volcanological to Tacitus are finely observed. at times produced a column of ash observatory in “A cloud . . . was ascending,” he 32 km tall, and that about 4 km3 the world. writes, of ash was erupted in about 19 the appearance of which I hours. Initially up to 3 m of tephra cannot give you a more exact and pumice fell on Pompeii, description of than by likening followed by up to 1.5 m of extremely it to that of a pine tree, for it hot pyroclastic flow (also known as shot up to a great height in the glowing avalanches), followed in form of a very tall trunk, which turn by up to 1.5 m of tephra and spread itself out at the top into pumice again. Eventually everything . . . branches; occasioned, I was buried except the roofs of some imagine, either by a sudden two-story buildings, while the port gust of air that impelled it, the town of Herculaneum was buried force of which decreased as it under 20 to 23 m of extremely advanced upwards, or the cloud hot pyroclastic flow deposits. It is itself being pressed back again believed that the destruction of Pliny the Younger by its own weight, expanded in life and property was principally 10 Aftershocks due to the pyroclastic flows, whose eruption, it is through volcanic properties at risk in excess of extremely dangerous effects were eruption modeling that we can $80 billion. According to Italy’s not well understood at the time. gain a realistic sense of what would Department of Civil Protection, 25 happen should Vesuvius erupt separate towns would be at risk in The Vesuvius Observatory, founded today. Such an eruption is by no the event of an eruption, and plans in 1841 on the slopes of the volcano means impossible. An eruption are in place for the evacuation of as but now situated in Naples, is the in 1631 killed over 3,000 people. many as 700,000 people. Without oldest volcanological observatory Vesuvius’s last eruption phase these preparedness plans, informed in the world. Run by the National started in 1913 and culminated by detailed risk models, the risk to Institute of Geophysics and in March 1944, when it destroyed life would be substantially worse. Volcanology, it monitors all of the the villages of San Sebastiano Campanian volcanoes (Ischia, al Vesuvio, Massa di Somma, According to a 2009 Willis Research Vesuvius, and the Phlegraean Ottaviano, and part of San Giorgio Network report, a major eruption Fields, as well as Stromboli), a Cremano. An earlier eruption, on of Vesuvius today—modeled on enabling long- and short-term April 5, 1906, killed more than 100 an approximation of the 1631 forecasting. The observatory people, ejected the most lava ever eruption—could result in 8,000 monitors seismic activity, ground deformation, and gravimetric and recorded from a Vesuvian eruption, fatalities, 13,000 serious injuries, magnetic field variations, as well and caused the 1908 Olympic and total economic losses of more as changes in the composition Games to be held in London than $17 billion (2008 values). and temperature of the gases instead of Rome due to financial emitted from fumaroles, soil, and difficulties. Visitors to Pompeii see the story of groundwater. Vesuvius written in the ash and the At present, around 1.7 million ruins. The story of a new eruption While the observatory can provide people live in the potentially could well be written in numbers early warning of an impending affected area, with the value of like these. Aftershocks 11 BUILDING ON EXPERIENCE Risk Modeling By understanding the possible effects of past disasters in today’s world, we have a better chance of mitigating the impacts of future events. One way of doing this is through the lens of risk modeling, which explains risk as a function of hazard, exposure, and vulnerability. 12 Aftershocks Hurricane Irma’s cloud structure as seen by NASA’s Atmospheric Infrared Sounder (AIRS). Image: NASA Risk models are created using related data. The most fundamental an earthquake; values for surface a combination of science, data define historical events, in roughness are needed to define the technology, engineering particular their date, geographical distribution of wind speed from a knowledge, and statistical data to location and extent, and maximum tropical cyclone; and topographic simulate the potential impacts of intensity. data from a digital elevation model natural and man-made hazards. (DEM) are needed to determine The interaction of the hazard When used probabilistically, risk flood depth. event with the exposed population models estimate the likelihood and assets (or built infrastructure) of extreme events and the Exposure: What could be determines its impact. More probable severity of their impacts. damaged? specifically, the amount of The models simulate hazard damage experienced in an event events that occur over periods Exposure describes the location, is estimated using vulnerability ranging from tens to hundreds of attributes, and value of assets— relationships that translate thousands of years. Overall, the which for the purposes of this the event intensity (e.g., wind simulated hazards have statistical definition includes people—that speed or flood depth) and asset characteristics that are consistent are important to communities characteristics (e.g., construction with observations from the historical and that could potentially be type, year built, building height, record, and they are designed to affected by natural hazard events. etc.) into scale of damage. include a wide range of possible Exposure modeling techniques hazard events, including those that have been developed to describe Risk modeling requires that the aren’t in the historical record. the distribution of multiple types scale and resolution of hazard, of exposure at various geographic exposure, and vulnerability data When used deterministically, risk scales, from global to local. Global are appropriate for the problem models simulate a single event, but scale modeling tends to take a of interest. It also calls for the multiple realizations of an event are top-down approach, with work creation of multidisciplinary, used to account for uncertainty in being carried out by governments multi-institutional platforms and spatial distribution and intensity. For example, there may be or large institutions, whereas local the establishment of nontraditional only a few accurate and precise scale modeling works from the partnerships around the technical analysis. measurements of an historical bottom up by methods such as hazard event, but the complete crowdsourcing and in situ surveys. Hazard: What could happen? spatial distribution of the event is needed to assess its impact on the Data sources for exposure A hazard is a potentially exposed assets. modeling might for example destructive physical include household surveys, phenomenon (e.g., an earthquake, We need data on the various aerial photos, and architectural a windstorm, a flood), and its factors that influence a hazard in drawings at a local level; GIS data, likelihood is an essential measure order to generate a hazard catalog. investment listings, and business in the quantification of risk. Once Knowledge of the distribution of listings at a regional and provincial the hazards of interest are defined, soil types, for example, is required level; and census data, global the next step often involves to model the spatial variation of databases, and remote sensing at a acquiring a variety of hazard- ground acceleration (shaking) from national level or above. 14 Aftershocks Vulnerability: How bad could the Loss metrics: What is the Better records of disaster losses damage be? potential loss? would be extremely useful for managing disaster risk. To meet Vulnerability describes the The damage to each asset affected the need for more complete and characteristics that determine by an event is combined with systematic disaster information, how susceptible exposed assets all others to determine the total the United Nations Office for are to the effects of a hazard. impact for an event. If the model Disaster Risk Reduction (UNISDR) Methods of assessing damage vary is being used deterministically and developed the open source Sendai greatly depending upon a number there are multiple realizations of a DesInventar Disaster Information of factors. The first is the type of single event, then the distribution Management System, a tool exposure under consideration; of losses is a function of the designed to systematically analyze people, buildings, and livestock, uncertainties around the hazard disaster trends and impacts, and for example, are susceptible to characteristics. If a model is being thereby help guide actions to very different types of damage. used probabilistically, then losses reduce the impact of disasters on The second is the resolution of from all the events in a hazard the communities. catalog are used to define a variety the exposure information; damage of statistical measures such as the Different approaches can be information based on fine-grained average loss expected each year. used to estimate the uncertainty site-specific data will differ from of modeled losses, and these damage information for coarser For a variety of reasons, modeled uncertainties apply to the specific aggregate data (at postal code losses based on the simulation of model used. Thus, in an ideal resolution or lower). The method a single event often differ from case, multiple models are used of assessing damage depends finally observed losses actually produced to estimate disaster risk. Using on the details available for a given by the event—for example, multiple models allows us to better resolution; the method used when modeled losses represent only represent—and make decisions detailed structural information is losses that are captured by the in light of—the uncertainty in available will differ from that used model, and these losses depend estimated loss. This includes the when just occupancy is known. upon the quality of the exposure uncertainly due to our incomplete data, the way that event intensity knowledge of hazard, vulnerability, Vulnerability functions are used to is modeled, and the quality of and exposure data, but also the estimate the severity of damage, the vulnerability information. In uncertainty introduced by our or probability of a certain level reality, losses are often adjusted chosen modeling approaches. of damage, being sustained by for a variety of additional factors, a type of structural asset when such as the need to replace a exposed to a given intensity of structure if damage exceeds a hazard. Vulnerability functions certain threshold or to account are also used to describe impacts for business interruption costs on population or environment by for commercial or industrial relating hazard intensity to various properties. Another consideration measures of damage suffered is that actual loss data are difficult by the population or system of to collect in a comprehensive and interest. accurate manner. Aftershocks 15 Mexico: Aerial view of rescue workers at the site of a collapsed building after the September 2017 earthquake in Mexico City. Photo: Manuel Velasquez/Anadolu Agency/Getty Images FAULT LINES The Mexico City Earthquakes of 1985 and 2017 A comparison of the earthquakes that hit Mexico City in 1985 and 2017 shows that much has improved since the first disaster. Remodeling the 1985 event helped identify buildings that were susceptible to damage in future events. Aftershocks 17 1985 1985 Zumpango Zumpango Zumpango Zumpango 2017 2017 Mexico Mexico City City Mexico Mexico City City Nezahualcoyotl Nezahualcoyotl Nezahualcoyotl Nezahualcoyotl MMI n 3–4 n 4–5 n 5–6 n 6–7 n 7–7.5 Shake maps showing the relative ground motions in terms of Modified Mercalli Intensity (MMI). Maps: USGS and Axis Maps MMI MMI 3–4 3–4 4–5 4–5 5–6 5–6 6–7 6–7 7–7.5 7–7.5 The 1985 Mexico City earthquake 1985 earthquake demonstrated with buildings of between 6 and 15 struck shortly after seven in the great clarity the danger that distant stories, and most of them had morning of September 19. It earthquakes pose to medium- and been built prior to the 1976 originated in the Pacific Ocean high-rise buildings constructed Mexico earthquake code. Some of just off the coast of Michoacán on poorly consolidated soils, these buildings represented vital state in the area of the Rio Balsas which amplify the type of ground infrastructure: the partial collapse estuary, with its epicenter nearly motion to which they are already of the Ministry of Communication 400 km away from Mexico City. susceptible due to their longer and Transportation with its tall This was a major earthquake, with period of vibration. microwave tower effectively cut a magnitude of 8 at a depth of off long-distance communications just under 20 km. For a number The earthquake shook the parts between Mexico City and the rest of reasons, it was an historically of Mexico City built on the old of the world. Thirteen hospitals devastating event for the capital. lakebed for over three minutes with were partially or totally destroyed, strong seismic waves that repeated with the loss of one in four available Much of central Mexico City is built every two to three seconds, while beds. Two major hospitals—Juarez on Lake Texcoco’s ancient, drained in the hilly parts of the city people and General—collapsed entirely, bed, whose poorly consolidated barely perceived the motion. causing the loss of 890 lives. Water soils can cause an amplification During the quake itself and the and electricity supply and public effect of low-frequency ground powerful (Mw 7.6) aftershock that transport were widely disrupted. motion during strong distant or occurred 36 hours later, 2,177 deeper earthquakes. It was these buildings were damaged to the The destruction of two massive low-frequency seismic waves that extent that they were deemed apartment blocks in the Tlatelolco affected Mexico City the most, not repairable, and 859 collapsed housing complex was a particularly because of the distance from the completely or partially, trapping egregious loss, accounting for source—most high-frequency thousands under the rubble. a part of the 30,000 residential ground motion in an earthquake units lost across Mexico City. The is filtered out at relatively short Most of the collapsed structures 13-story Nuevo Leon apartment distances from the epicenter. The were reinforced concrete framed block collapsed completely, killing 18 Aftershocks 468 people. “I turned toward the National System for Civil Protection changes in response to the 1985 Nuevo Leon and I saw that it was (SINAPROC) was established earthquake. The code has proved collapsing, first like a sandwich, in 1986, the year following the an excellent first line of defense and then twisting and falling,” earthquake. Initially designed against earthquake damage, and reported Cuauhtemoc Abarca, a to improve Mexico’s planning, has been used as a template for neighborhood leader at the time. response, and recovery capacity, other codes, both within the “I saw but couldn’t believe it, and SINAPROC has evolved to focus on country and abroad. However, like then a cloud of dust went up.” building an end-to-end disaster risk codes elsewhere in the world, it is It was believed at the time that not always adequately enforced. management system encompassing somewhere between 10,000 and In 1995 Roberto Meli, director of risk identification, prevention, 13,000 lives were lost, although the CENAPRED, suggested that poor reduction, and financing as well official toll in 2015 puts the number enforcement would eventually come as post-disaster reconstruction. In at 7,500. Around 4,000 people were to light: “The next temblor will be in 1988, Mexico established its National pulled out alive from the rubble. charge of identifying where things Center for Prevention of Disasters Damages were estimated at were badly done,” he said. $4 billion in 1985 prices. (CENAPRED), a federal agency tasked with warning citizens about Modeling future losses Building back better possible disasters. Rather than relying on an The damage and losses from the Mexico City’s building code, earthquake to identify poor earthquake prompted the city to take established in the 1940s and building code enforcement, some significant steps to mitigate the repeatedly modified over the however, Mexico City took action effects of future disasters. Mexico’s years, underwent significant on its own. In 2015, ERN, a Expected damage (white, low damage; red, high damage) in downtown Mexico City due to a Mw 8.0 earthquake in the subduction zone. Ground motion is also shown (low intensity in blue, high intensity in red). Image: ERN Aftershocks 19 Tenochtitlan and Gulf of Mexico, 1524. Image: Wikimedia Commons FATED TO FALL of the sediments was amplified by this of the North American, Cocos, and Mexico City was originally built by the resonance, causing greater shaking Pacific tectonic plates, whose movement Aztecs on an island in the middle of on them; this shaking in turn had a against each other causes more than 90 Lake Texcoco, which was later drained particularly damaging effect on buildings tremors every year. The presence of soft by the Spanish to prevent flooding. of 6–15 stories, because those buildings lake sediments means that Mexico City The silt on which part of the city rests also experience resonance at the same could again experience amplified ground has a high water content, and the soft shaking during earthquakes that occur on sediment resonates when affected by low frequencies. While Mexico City is not these distant faults. low-frequency seismic waves, such as situated in the direct vicinity of a fault line those that reached the city from the (unlike San Francisco or Los Angeles), distant earthquake in 1985. The motion Mexico itself is located on the confluence 20 Aftershocks At the time of the 1985 earthquake, across the city. It killed 370 people, the extremely large amplification including 228 in Mexico City and effect of the ancient lakebed was 34 in the city of Puebla. Some of not fully anticipated, although it the characteristics of the collapsed had been observed during the structures had been identified as Mw 7.6 earthquake of July 28, vulnerabilities in the ERN survey, 1957. “The engineers at the time and much of the damage followed did not know that the amplification the patterns identified in the risk of the motion was going to be that model. “We already knew that large,” says Dr. Eduardo Reinoso these types of buildings were not of ERN. “Nobody in the world did. going to behave well, and it is going This effect is now included in the to happen again in the future. models, and the code, so that there The problem is it is expensive to are no surprises.” mitigate the risk,” says Dr. Reinoso. Testing the model Overall, however, the September 2017 earthquake suggests that Occasionally, a risk model will be Mexico City’s implementation tested by an actual disaster. In of the building code regulations 2017, 32 years to the day after the (introduced in 1987, 1993, and disaster of 1985, central Mexico 2008) had improved the resilience was struck by an intermediate- of the city, reducing significantly depth earthquake of magnitude the number of lives lost and 7.1 and about 55 km deep—just buildings damaged, although two hours after an earthquake detailed analysis comparing the preparedness drill had been two earthquakes is yet to be Mexican consultancy specializing conducted in Mexico City. completed. More work remains in the evaluation of natural According to the Mexican Seismic to be done to further improve risks, conducted a survey of 150 Alert Early Warning System buildings’ resilience. Much of the buildings in Mexico City to assess (SASMEX), residents received damage of the 1985 earthquake their compliance with the code. advance warning of 20 seconds as was caused by poorly designed or The survey found that over 30 the epicenter was 120 km to the executed construction, in a city percent of the buildings did not south-southeast of the city; some which at the time was the fastest comply with the regulations. people reported that the warning growing in the world. ERN also built a model predicting time was less than that, while many future losses according to building believed the warning was simply Rapid visual screening surveys type for an earthquake similar in part of the earlier drill. on the ground can provide block- magnitude to the 1985 event—an by-block information on high-risk essential tool for businesses and The earthquake was again felt structures, informing risk modeling institutions seeking to mitigate strongly on the old lakebed of and decision making and in turn future loss in an urban area. Mexico City and caused the building resilience into the city’s collapse of more than 30 buildings future growth. Aftershocks 21 SHADOW OF THE PAST Mount Tambora, Indonesia, 1815 The most powerful volcanic eruption of the last 1,000 years had global consequences— but its effects, revealed by risk modeling, would likely be far worse today. 22 Aftershocks Aftershocks 23 The eruption of Mount Agung, Bali, Indonesia, November 2017. Photo: Muhammad Fauzy/NurPhoto via Getty Images In the early evening of April 5, and blocked out the sun across an km3 of debris—enough to bury the 1815, the volcano Mount Tambora 800-km area for at least two days. island of Java under 35 cm of ash. on the Indonesian island of Forty-eight hours after the second Sumbawa began to erupt in a eruption, the area covered by Actual loss of life from this event series of explosions that could be tephra of 1 cm thickness or more is not known, but it is estimated heard 1,200 miles away. After a had reached around 800,000 km2, that around 12,000 people died lull in activity, a second and even equivalent to the size of Pakistan. during the eruptions on the island stronger eruption occurred five It was the most devastating of Sumbawa. The indirect toll— days later, lasting until the evening volcanic event of at least the related to famine and disease in of the 11th; by this time the top past 1,000 years: measuring Sumbawa and Lombok—was much 3,000 feet of the mountain, then an estimated 7 on the Volcanic higher, perhaps as high as 60,000, a graceful cone like Mt. Fuji in Explosivity Index (VEI), it was although numbers as high as Japan, had collapsed into a caldera 10 times more powerful than the 100,000 have also been proposed that is today 6 km across and 1 km better-known 1883 eruption of to allow for further possible deep. Krakatoa, and 1,000 times more loss of life in Bali and East Java. powerful than the eruption of Thousands died from severe The second eruption sent a plume Eyjafjallajökull in Iceland in 2010. respiratory infections caused by of ash 20 km into the atmosphere The eruption produced around 50 inhaling the ash that remained in 1815 Eruption of Mount Tambora Facts & Figures 20 km Blocked ~1 cm Measure 12,000 60,000– 1816 plume out the sun of tephra of 7 on fatalities 100,000 “Year without a of ash across reached the VEI due to indirect summer” 800 km around eruption fatalities Average global 800,000 km2 temperature drop 5.4 °F/3 °C Toba Supervolcano Vesuvius Tambora Krakatau Katmai Mt. St. Helens El Chichón Indonesia Italy Indonesia Indonesia Alaska Washington Mexico 75,000 years ago 79 AD 1815 1883 1912 1980 1982 Illustration: Andrea Fernandez 24 Aftershocks The painter J. M. W. Turner’s sunsets are thought to have been influenced by the “year without a summer” of 1816. Image: Wikipedia the atmosphere, and thousands and creating a global cooling effect Another consequence of that from diarrheal disease caused by that resulted in “the year without gloomy year was its influence drinking water contaminated with a summer” that was 1816, when on some of the great art of the acidic ash. The same deadly ash it was estimated that the average period, from Turner’s rich sunsets, poisoned crops, especially the vital global temperature was reduced to Mary Shelley’s Frankenstein, rice fields, raising the death toll by 3 °C. composed in the global shadow of higher. the greatest volcanic eruption of The disruption to weather the age. While the devastation in Indonesia patterns resulting in part from was particularly severe, the What if a Tambora-scale the eruption caused crop failures eruption of Mount Tambora had eruption happened today? and famine in Europe and lasting—even historic—global North America, and may have effects. The eruption flung an Globally, the consequences of a accelerated the settlement of the estimated 60 million tons of Tambora-scale event would be sulfur gas over 40 km into the American West by New England far more disruptive if they took stratosphere, where it combined farmers seeking better growing place today. The eruption of with hydroxyl radicals to form conditions. In China and Tibet, Eyjafjallajökull, with a VEI of 4 particles of sulfuric acid. Within the cold weather destroyed rice and one-thousandth of the ejected months, this was distributed production and killed livestock, volume of Tambora, closed air globally throughout the and surviving crops were space over northern Europe and stratosphere, reflecting sunlight destroyed by unseasonal flooding. disrupted air travel for eight days. Aftershocks 25 1815 Tambora reanalysis Pontianak Samarinda isopach with tephra loading Palu measured in kPa. Map: D-RAS, Axis Maps Bandjarmasin Ujungpandang Semarang Surabaya Cilacap kPa 0.1–0.5 0.5–1 1–1.5 1.5–2 >2 Pontianak Samarinda Palu Bandjarmasin Ujungpandang Semarang Surabaya Cilacap Absolute losses aggregated to a province level for a remodel of the 1815 eruption. Losses (US$ millions) <500 500–2,000 2,000–5,000 5,000–6,200 Map: D-RAS, Axis Maps 26 Aftershocks The eruption grounded Every volcano is different, and However, this model can also 107,000 flights, costing the aviation each eruption produces a unique quickly analyze smaller-scale future industry an estimated $1.7 billion. combination of the various forms events and be used to determine A Tambora eruption today would of ejecta, including magma and losses in the residential sector. likely prove more disruptive, for a volcanic gas. Of these hazards, longer period, over a much wider volcanic ashfall and gases are the There are 127 active volcanoes in most far-reaching, and they can Indonesia alone, and over 1,500 area. Southeast Asia is one of the affect areas hundreds or even globally—many of them situated most densely populated regions in thousands of kilometers downwind on the densely populated Pacific the world, with correspondingly of the volcano. Ashfall—such as Rim—the “Ring of Fire” that busy air traffic routes. The regional that caused by the 1815 eruption— gets its name from the region’s economy would suffer devastating is perhaps the easiest to measure. high levels of volcanic (and effects on food production, Its effects are also particularly seismic) activity. The eruption of tourism, and commerce. Mount Merapi in 2010 produced serious, ranging from an impact on agricultural production, to enough ashfall to cause buildings Tambora erupted before the advent to collapse under its weight; public health consequences such of industrial farming, and at a time as respiratory disorders, to the data of the sort provided by the when the global population had disruption of public services remodeling of Tambora might have just passed the 1 billion mark. A through damage to equipment or allowed for better planning for the similar event now would likely have infrastructure. losses in that event. a more devastating effect on crop production and hence on global In order to estimate some of the What has changed? food security. In terms of loss of economic damages and losses to life, it’s impossible to estimate the region in the case of a similar Since the Indian Ocean tsunami the effect of a Tambora today. event, the World Bank Disaster- of 2004, which devastated the At the time, the region including Resilience Analytics and Solutions province of Aceh, Indonesia has (D-RAS) team remodeled aspects deliberately sought to develop Sumbawa, Lombok, and Bali was of the original eruption for 2017. and implement a complete and home to 750,000 people; today over Model results suggest that within modern disaster risk management 9 million people live there, the affected 300 km radius, damage system. The country has enacted 1.4 million of them on Sumbawa to residential buildings alone would legislation on disaster management, and its smaller offshore islands. be in the order of $9.7 billion today. established the National Disaster While today there is a much Management Authority (BNPB), improved capacity to deal with What about the future? and drafted the National such events through timely Disaster Management Plan. The warnings and evacuation ability, the Tambora-scale events are rare. government has also prioritized global toll that might result from And the 1815 eruption, at a the identification of risk: it has a loss of agricultural production comparatively recent point in the developed a national risk atlas to would be considerable. past, means that another eruption map exposure to natural hazards of such ferocity is unlikely to across all of the country’s districts, happen again at the same site. assessed provincial- and local-level Aftershocks 27 risk, and adopted open source resulting advanced capacity—in software for community mapping the form of experts, training, and projects. All this information equipment—enabled accurate on risk in turn is used to inform prediction of the 2010 eruption and national and local planning and the successful evacuation of 70,000 budgeting. people. Following the devastation in This improved capacity was also 2004, with technical and financial evident during the threatened support from the World Bank and eruption of Bali’s Mount Agung other donors, the government of in 2017. At that time, manually Indonesia also piloted REKOMPAK, activated early-warning sirens with an approach to large-scale a range of some 2 km were placed reconstruction and rehabilitation in several townships in the likely designed to support community- path of magma or pyroclastic flow, based efforts to build back better and 144,000 people were evacuated after a disaster. The REKOMPAK from particularly vulnerable areas model has been used after a to shelters established by the range of disasters, including local disaster management agency earthquakes, volcanic eruptions, (BPBD). One of the challenges was landslides, and flooding. To cite two the reluctance of some community examples: it was used following the members to leave their homes or earthquake affecting Yogyakarta their livestock. in 2006, and after the eruption of Mount Merapi in 2010, when it In 1815, news of Tambora spread supported voluntary relocation of at the speed of sail; the eruption communities at risk. of the much smaller Krakatoa some seven decades later The eruption of Mount Merapi was carried around the world provided an opportunity to by telegraph. Today, modern test Indonesia’s disaster risk communications technology alone management system. Before that would dramatically mitigate the event, the Indonesian Center immediate loss of life from an for Volcanology and Geologic eruption, and social media would Hazard Mitigation had requested screen it around the world in real assistance from the Volcano time. Disaster Assistance Program of the U.S. Geological Survey (USGS) to The Sanggar Peninsula and the crater of Tambora on Sumbawa, Indonesia. improve volcano monitoring. The Map: Heinrich Zollinger 28 Aftershocks EYEWITNESS: SIR THOMAS STAMFORD RAFFLES Sir Thomas Stamford Raffles was the truly tremendous, frequently shaking the British lieutenant general resident in earth and sea violently. On the morning of Sumbawa at the time of Tambora’s the 3rd April, ashes began to fall like fine eruption. A keen amateur scientist, he snow, and in the course of the day they directed his representatives in the affected were half an inch deep on the ground; from areas to send him detailed accounts of the that time till the 11th the air was constantly eruption and its aftermath. The following is impregnated with them, to such a degree part of his own description: that it was unpleasant to stir out of doors . . . The sun was not visible till the 14th, and At 10 pm of the 1st April we heard a during this time it was extremely cold—the noise resembling a cannonade, which ashes continued to fall, but less violently, Thomas Stamford Raffles. lasted at intervals till 9 o’clock the next and the greatest depth, on the 15th of Engraving: James Thomson day, it continued at times loud, at others April, was 9 inches. resembling distant thunder—but on the night of the 10th the explosions became Aftershocks 29 THE LESSONS OF VULNERABILITY Spitak Earthquake, 1988 30 Aftershocks A ruined building near Mount Aragats in the aftermath of the 1988 Spitak earthquake, northern Armenia. Photo: Pascal Parrot/Sygma/Sygma via Getty Images A remodeling of the 1988 Spitak earthquake in northern Armenia demonstrates how socioeconomic factors can worsen the damage and loss from a devastating event and impede recovery efforts. Northern Armenia is located on a to human error and economic seismic belt that stretches from neglect. the Alps to the Himalayas, and as a result is vulnerable to large and Around 350 multistory apartment destructive earthquakes. One such buildings collapsed during the was the Armenian earthquake of event, killing about 20,500 people 1988—also known as the Spitak (although other structures stood undamaged or only moderately earthquake—centered around the damaged nearby, particularly the cities of Spitak, Leninakan (now nine-story large precast reinforced Gyumri), and Kirovakan (now concrete panel buildings). Several Vanadzor). thousand low-rise, unreinforced stone masonry houses also The Spitak earthquake, which collapsed across urban and rural struck in the late morning of areas, killing another 4,500 people. December 7, 1988, was caused The city of Spitak in particular by a fault rupture 40 km south of was almost entirely destroyed; it the Caucasus Mountains. It had lost around half of its residents to a shallow hypocenter, originating the quake, and the rest were left relatively close to the surface, and homeless. with a magnitude of 6.8 was one of the largest earthquakes ever Most of the multistory apartment to strike the region. Some of its blocks that collapsed in the effects, however, may be attributed earthquake were poorly Aftershocks 31 constructed Soviet-era building and loss. Unfortunately, these of buildings using a number of stock. Particularly devastating was produced many conflicting studies, mostly from the National damage in the health care sector. numbers, including some huge Statistical Service of the Armenian Most hospitals collapsed, killing overestimations of the economic government, and examined two-thirds of the doctors in the losses. The valuation of losses was historical damage data, intensity region and limiting capacity to complicated by the constantly maps, and ground motion maps handle the critical medical needs changing rate of the Soviet-era in order to gain the best possible after the disaster. The disaster also ruble, which in the construction reanalysis of the scenario. This had long-term economic effects: industry was then around one- study produced the first definitive aside from imposing immediate ninth of the U.S. dollar. estimate of losses from the event. economic losses and the cost of rebuilding, the earthquake In 2017, the D-RAS team of the Specifically, the study estimated destroyed 130 factories, putting World Bank conducted a reanalysis that the earthquake caused 170,000 people out of work. of the event’s effects on the $150–200 million3 of damage to the residential sector, both to get a residential sector as it was at the Revisiting the damage more accurate view of the original time of the event. The reanalysis losses and to establish what for today’s residential exposure The Spitak earthquake was damage would likely result from an suggests around $420 million in marked by a large number of earthquake of similar magnitude damages. In relative terms, this is studies on post-disaster damage today. The team modeled exposure a reduction in the ratio of loss to The figure is in 1988 U.S. dollars and assumes an exchange rate of 8.8 rubles to the dollar. 3 GEORGIA GEORGIA Tovuz Tovuz Ijevan Ijevan Vanadzor Agdam Vanadzor Agdam Gyumri Gyumri Gadabay Gadabay Gavarr Gavarr Ashtarak Ashtarak Yerevan Yerevan Artashat Artashat MMI Loss as % of Residential Value 4.0 5.5 7.0 8.5 10 0–20 20–40 40–60 60–80 80–100 Hazard map showing Modified Mercalli Intensity. Relative loss from the Spitak earthquake on a 1 km resolution for the Map: D-RAS, Axis Maps reanalysis as a percentage of total exposed value. Map: D-RAS, Axis Maps 32 Aftershocks Historic (1988) vs modeled (2017) residential exposure and damage costs for Armenia. The loss ratio for 1988 is 7.06 percent; for 2015, it is 4.28 percent. Graph: D-RAS, Rick Murnane 9,791 n Residential stock (US$ millions) n Residential damage (US$ millions) 2,123 419 150 Loss Estimate: 1988 Exposure Loss Estimate: 2015 Exposure exposed value—loss ratio—as the Despite these findings showing apartment buildings and critical figure above demonstrates. a reduction in relative loss, facilities such as schools, hospitals, challenges remain. For various and factories are destroyed in an Improving construction reasons, economic growth in earthquake. The same high levels Armenia has been muted, resulting of earthquake risk exist in other The projected reduction in relative in slow replacement of Soviet- regions in Armenia: Armenia’s loss is due in part to changes in era building stock and creating capital Yerevan, for example, is building construction. In the period concern about the degradation of threatened by the Garni fault, after independence (starting in metal joints in the panels of large and most of its residents continue 1991), the construction typologies pre-cast concrete buildings. By to occupy vulnerable pre-1988 that fared poorly in 1988 were 2016, post-1990 housing stock buildings that may provide lesser entirely discontinued and were was estimated to make up only safety during an earthquake. replaced by superior cast-in-situ about 13 percent of the total built reinforced concrete construction. floor area. Should a similar event This reanalysis supports the case The reduction may also in part be occur, reconstruction costs would for improvements in building attributed to the fact that fewer likely be higher given the improved stock and critical infrastructure people and properties are now construction standards required for across Armenia. It also suggests located in the regions of northern new buildings. decreased economic loss ratios Armenia affected by the 1988 and improved life safety could event. After the earthquake, there The return period of a quake of this result from the development of was a significant exodus, and cities magnitude in the affected region earthquake-resistant infrastructure have not recovered their earlier is estimated at around 250 years, and improved building design. population levels: Gyumri and equivalent to a 0.4 percent chance Vanadzor—Armenia’s second- and of it occurring in any given year. third-largest cities—are each The Spitak earthquake showed the roughly half as populous at present potential for severe consequences as they used to be in 1988. when so many residential Aftershocks 33 A Malagasy woman manually pollinates a vanilla flower near Sambava, Madagascar. Photo: © Pierre-yves Babelon | Dreamstime.com A FRAGILE HARVEST Tropical Cyclone Enawo, Madagascar, 2017 A tropical cyclone in Madagascar devastated vanilla production and disrupted the industry globally. Remodeling this event may help limit the impact of future extreme weather events. Aftershocks 35 CYCLONE ENAWO 2017 Antsiranana Antsiranana Antsiranana Mahajanga Mahajanga Mahajanga Toamasina Toamasina Toamasina Antananarivo Antananarivo Antananarivo Antsirabe Antsirabe Antsirabe Fianarantsoa Fianarantsoa Fianarantsoa Toliara Toliara Toliara % of TEV Maximum Wind Speed (kph) Accumulated Flood Depth (mm) 0– 0. 1– 5– 10 50 1– 5 –5 10 –9 0. 60 90 120 160 200 0 10 20 50 100 1 1 0 0 Modeled Wind Hazard. Map: World Bank, Modeled Flood Hazard. Map: World Bank, Agricultural Losses as Percentage of TEV. Axis Maps Axis Maps Map: World Bank, Axis Maps In March 2017, Tropical Cyclone with 81 deaths and 250 injuries. Madagascar produces almost 4,000 Enawo swept through Madagascar, More than 40,000 houses, 3,300 tons of vanilla every year, over one- making landfall in the northeast classrooms, and 100 health centers third of the world’s total. Vanilla’s as a Category 4 cyclone and then were damaged. But Enawo also relatively limited global production moving southward as a tropical had immense consequences for the makes the price of vanilla beans depression before exiting the economy of the country and for the highly susceptible to bad news. country. Northeastern Madagascar vanilla industry worldwide. Prices had increased from $100 per suffered wind damage and kg in 2015 to $500 per kg in early widespread flooding, and the 2017, for a number of reasons, A vulnerable market central and southeastern parts of including rising global demand and the country were affected by heavy speculative hoarding by producers. After years of price increases, rains and flooding. Enawo kicked this trend into many farmers in Madagascar had overdrive: the modeled direct become increasingly dependent Enawo was the strongest cyclone damage to the vanilla crop and its on the crop, putting all of their to strike Madagascar since 2004; associated loss of productivity was resources into vanilla production. with maximum sustained wind estimated at $164 million out of a speeds of 230 kph at landfall, it This left them particularly total production worth $1 billion in dropped up to 220 mm of rain on vulnerable to the effects of the annual exports. By August 2017, Sambava in 24 hours. Preliminary cyclone. In the Antalaha commune the price of vanilla beans had field assessments conducted by of the Sava region, initial reports soared to a record $600 per kg on the government and partners indicated that 90–100 percent of global markets, and high prices estimate that close to 434,000 production was lost, threatening seem likely to continue through people were affected by the event, many families with ruin. 2018. As the Malagasy proverb 36 Aftershocks “All who live under the sky are woven together like one big mat.” —Malagasy proverb suggests, everything in the world million and were dominated by risk models marks an important step is connected, and the destruction the impact on vanilla plantations, forward in Madagascar’s ability to of a local industry may have global which amounted to losses understand the risk and mitigate the consequences. estimated at $164 million in the potential impact of cyclones. Model Sava and Diana regions. results can help the government Three risk models develop rapid post-disaster Communicating risk contingency financing instruments; Three complementary approaches however, while such instruments were used to model losses from Post-event loss calculations can help in managing the financial Enawo and the risk from future complement damage and loss impacts, they do not actually events of a similar scale: assessments involving on-the- reduce those impacts. If effectively ground evaluation. In the case communicated, risk information, 1. Using a quantitative risk of Tropical Cyclone Enawo, the derived from risk models, may also modeling approach, AIR modeled loss approach offered help Madagascar’s vanilla farmers— Worldwide estimated losses an early estimate of the economic as well as major producers—better resulting from direct damage impact of the cyclone, which the prepare for future weather disasters to buildings and infrastructure government has been able to use by reducing the vulnerability of at around $208 million (2015 to start the recovery planning their crops and diversifying their dollars), with a mean return process. Access to state-of-the-art livelihoods. period of around 11 years for similar events. POD OF GOLD 2. The African Risk Capacity (ARC) model is based on historical data for over 30 years and simulated data for over 1,500 years. It has produced risk profiles for the Comoros, Madagascar, Mauritius, Mozambique, the Seychelles, and Zanzibar, and is used to facilitate insurance payouts for events of varying magnitudes. ARC’s model estimates the economic Vanilla beans drying in Sambava, Madagascar. loss generated by Enawo at Photo:© Sebastién Shauvel | Dreamstime.com $50–60 million. Vanilla is a type of orchid that requires pollination to produce the pods from which the flavoring is derived. Native to Mexico, where it was cultivated by pre-Columbian 3. The D-RAS team at the World communities, vanilla was introduced to Europe in the 1520s. In 1841 Edmond Albius, Bank developed an agriculture a 12-year-old slave on the island of Réunion in the Indian Ocean, discovered that sector model to assess vanilla could be hand-pollinated, enabling its cultivation in suitable climates around agricultural losses from an the world. But hand pollination, together with the maintenance of the vines and the harvesting of the crop, means that farming vanilla is particularly labor-intensive, and Enawo-scale event. These were explains why it is the second most expensive spice in the world, after saffron. estimated at approximately $207 Aftershocks 37 CONSTRUCTING RESILIENCE The 2010 Earthquakes in Haiti and Chile 38 Aftershocks Damage to Haiti’s Presidential Palace after the 2010 earthquake. Photo: arindambanerjee| Thinkstock.com In 2010, Haiti and Chile were both struck by devastating earthquakes. The earthquake that struck Haiti had a lower magnitude, yet Haiti suffered far greater damage and losses. Why was this the case? Remodeling reveals the role that resilient urban planning and building codes can play in limiting earthquake damage. Aftershocks 39 The focal origin of the Haitian quake was 13 km beneath the surface and just 25 km It is tempting to compare two vulnerability. There has even been devastating earthquakes that from the densely uncertainty around the intensity occurred in the same general time populated capital of the earthquake itself. Although frame, and indeed, many column of Port-au-Prince there are a lot of uncertainties inches have been devoted to the —in earthquake terms, regarding actual ground motions contrasts between the Haitian from the Haiti earthquake, the and Chilean earthquakes of 2010. close to a direct hit on modeled analysis of the earthquake Remodeling the former disaster, the capital. has refined the available knowledge however, helps explain the by comparing the original ground significant differences in the losses motion estimates with building and impact associated with the two damages. earthquakes. In 2017, the D-RAS unit at the Devastation in Haiti These tens of thousands of World Bank remodeled the collapsed buildings led to extensive Haiti event in order to obtain an The Haiti earthquake of January loss of life in this earthquake. accurate estimate of potential 2010 was one of the most An estimated 3 million people losses had this event taken place destructive earthquakes in recent were affected by the earthquake, in the present time. This is a times. The Mw 7.0 earthquake and death toll estimates ranged worthy endeavor, as the Enriquillo- occurred on the eastern end of the from 100,000 to the Haitian Plantain Garden fault continues Enriquillo-Plantain Garden fault government’s estimate of 316,000, to accumulate strain that will be zone very near the capital city of though later studies emphasize that unleashed upon the Greater Port- Port-au-Prince. It devastated many the former is the more likely figure. au-Prince region in the future. The residential neighborhoods as well In the widespread devastation reanalysis provided an opportunity as the commercial district near the throughout Port-au-Prince and to investigate the vulnerability of port. elsewhere, vital infrastructure existing buildings by reviewing necessary to respond to the what is known about the A building-by-building damage disaster was severely damaged consequences of the 2010 event. survey carried out between or destroyed. This included all The model concluded that should February 2010 and February 2011 hospitals in the capital; air, sea, the event happen today, residential found that 79,500 buildings— and land transport facilities; and losses would be in the order of $3.2 approximately 20 percent of all communications systems. billion, compared with the $2.3 buildings in the affected area—had billion estimated for 2010. either collapsed entirely or were One of the challenges in damaged beyond repair, while an understanding the loss and impacts Comparison of catastrophes additional 102,000 buildings— of the 2010 Haiti earthquake approximately 26 percent—had has been the great degree of Six weeks after the Haiti repairable structural and/or uncertainty over many of the earthquake, Chile was hit by an nonstructural damage. relevant variables—including earthquake with a magnitude of building costs, exposure, damage Mw 8.8—in energy release terms, data, loss data, ground motion, and 500 times more powerful than 40 Aftershocks Comendador Port-au-Prince Bay Port-au-Prince Jimani Jacmel MMI n 4–5 n 5–6 n 6–7 n 7–8 n 8–8.7 MMI 4–5 5–6 6–7 7–8 8–8.7 Viña del Mar Mendoza Santiago San Bernardo Rancagua Talcahuano Concepción MMI n 2.7-3 n 3–4 n 4–5 n 5–6 n 6–7 n 7–8 n 8–8.9 Temuco Hazard maps of the Haiti (above) and Chile earthquakes of 2010, showing Modified Mercalli Intensity. Maps: D-RAS, USGS, Axis Maps MMI 2.7–3 3–4 4–5 5–6 6–7 7–8 8–8.9 Haiti Chile Magnitude of earthquake Mw 7.0 Mw 8.8 Depth of earthquake 13 km 35 km Maximum recorded peak ground acceleration (PGA) 0.30–0.70g (estimated) 0.65g Maximum recorded PGA near capital city 0.30–0.70g (estimated) <0.30g Population density of capital city ~25,000 people per km2 ~8,500 people per km2 Estimated casualties ~100,000 550 PDNA estimate of residential damage (2010) $2.3 billion $3.9 billion Modeled residential damage (2017) $3.2 billion $6.8 billion Aftershocks 41 the Haiti event. The earthquake and dependent upon both distant on the capital. Great subduction and tsunami claimed 550 lives—a and local conditions. While the earthquakes, such as the one that tragedy, but a tiny fraction of Chilean quake was much stronger, its struck Chile, last longer, as they Haiti’s loss of life. In Chile, 6.5 epicenter was offshore and its focal involve a much bigger fault rupture percent of the housing stock was origin deeper—about 35 km below zone (the 2010 event lasted for 1.5 either damaged or destroyed, while the surface of the Pacific Ocean to 2 minutes), and they produce in Haiti this ratio was more than and 325 km from the capital city longer period waves (affecting taller double, at 13.7 percent. of Santiago. By contrast, the focal buildings) that reach over a greater origin of the Haitian quake was 13 distance. The seismic waves that Why was the scale of destruction km beneath the surface and just 25 shook Port-au-Prince, although not and loss of life so much greater in km from the densely populated city recorded, were shorter and due to Haiti than in Chile? The reasons are of Port-au-Prince—in earthquake the proximity more violent, with substantially geological in origin, risk terms, close to a direct hit the strongest shaking occurring in 42 Aftershocks The Gran Torre Santiago is a 64-story tall introduced after the earthquake, it skyscraper (299.92 meters) in Santiago, Chile, the tallest in Latin America, and the is not well enforced. There is also second-tallest building in the Southern a shortage of licensed contractors, hemisphere. Photo: © Tifonimages | Dreamstime.com engineers, and architects to ensure regulations are adhered to during construction. As a result, Haitian buildings are often constructed were likewise lacking. After the with natural available materials, earthquake, the government, with such as the traditional clisse assistance from the United States, mortar houses (with walls from installed five new seismometers sticks and twigs covered by mud or and a surveillance network that cement mortar). Contractors also transmits timely information cut costs by using less expensive through the Internet on seismic and less resilient materials, activities in Port-au-Prince and including limestone dust and regions to the north. unrefined sand. In addition, many structures in Port-au-Prince are The frequent occurrence of built on steep slopes, without damaging earthquakes in Chile adequate foundations. prompted it to develop stringent building codes, comparable to Finally, population density those of California (although as in the affected areas helps to elsewhere in the world they are explain the different impact of not always uniformly enforced). the earthquakes. The population In recent decades, Chile has density in the city center of Port- mandated earthquake-proofing for au-Prince was over 25,000 people new engineered structures and per km2. In contrast, Santiago, the has required architectural designs most densely populated area in a narrow band of land of around 50 that include materials like rubber Chile, has a population density of km east-west and 20 km north-south. and features like counterweights just under 8,500 people per km2. to allow tall buildings to bend and There are also historical reasons sway rather than break during The earthquakes in Chile and for the greater devastation in Haiti. temblors. Haiti are remarkable perhaps Haiti has had far less experience more for their differences than with earthquakes than Chile—the Haiti, in contrast, has few their similarities. However, if the last significant earthquake to hit building regulations in place and juxtaposition of the two events Port-au-Prince had been in 1751. no integration of risk in urban is at all useful, it is because it Before the 2010 earthquake, Haiti’s planning. Residential buildings are highlights the value of resilient seismic surveillance network was still mostly informally constructed, urban planning and strictly applied almost nonexistent, and seismic and though the International construction standards in areas of risk preparedness and education Building Code (IBC) was seismic risk. Aftershocks 43 44 Aftershocks Devastation of Santo Domingo after San Zenon Hurricane in 1930. Photo: Keystone-France/Gamma-Keystone via Getty Images A DIRECT HIT San Zenon Hurricane, Santo Domingo, 1930 A risk model developed for the 1930 San Zenon Hurricane in the Dominican Republic yields valuable data on the likely effects a similar storm would have on cities in the developing world in today’s era of rapid urbanization. Aftershocks 45 In 1930, the value of the total residential and different types of construction with varying weather resistance, such nonresidential stock was $110 million in 1935 as wood, steel, concrete block, dollars; today, it is over $150 billion. and reinforced masonry. Spatially, the exposure was distributed over three types of development: the metropolitan Santo Domingo What happens when an Atlantic and mudslides. Three districts of area, other urban areas, and hurricane at the height of its the city were almost completely rural areas, with differences in strength scores a direct hit on destroyed. Estimates of the lives construction characteristics for a major city in a developing lost vary, from as low as 2,000 to as each administrative zone. country? Some answers to this many as 10,000. question are offered by the San Remodeling the 1930 hurricane Zenon Hurricane, which struck How was the storm modeled? proved challenging. There are Santo Domingo in the Dominican limited and often conflicting Republic in 1930, causing To establish an accurate view of the historical observations—for widespread destruction and the intensity and track of the storm, example, estimates of the storm’s loss of up to 8,000 lives. researchers examined the National radius of maximum winds start at Hurricane Center HURDAT data. 2 km, with other estimates higher. The storm—the second of three Storm data were then compared There are also limited data on the in one of the quietest hurricane against the exposure of residential housing stock for the country. seasons on record—originated in building stock in the Dominican the mid-Atlantic in late August. It Republic, obtained from census and The damage estimated in the was still intensifying when it made other data, and encompassing eight reanalysis was compared in landfall near Santo Domingo, with peak winds estimated at around 250 kph and gusts of up to 320 kph. The San Zenon Hurricane had a relatively small footprint: Cap-Haïtien although it left a trail of destruction Santiago 20 km wide, much of this was concentrated in the capital city. San Pedro Port-au-Prince Santo Domingo de Macorís The storm hit with pinpoint La Romana accuracy in a particularly vulnerable location. Santo Domingo is located on an exposed coastal Caribbean Sea plain, susceptible to flooding from the Ozama River, which broke Wind Intensity kph 58.9 103 148 192 236 its banks during the storm; other Hazard map of the 1930 reanalysis scenario including wind speed per cell. damage resulted from high winds Map: D-RAS, Axis Maps 46 Aftershocks Bonao Monte Plata El Seibo Relative losses on a 250 m grid cell resolution from the 1930 hurricane scenario. Map: D-RAS, Axis Maps Santo San Pedro Azua Domingo de Macorís San Cristóbal worst-case scenario in which a major metropolitan center is hit by Baní a very intense hurricane. Such a scenario can be useful for disaster risk management and planning. It also facilitates the production of Loss as % of Residential Value 0–5 5–10 10–15 15–20 >20 exposure, hazard, and vulnerability models for tropical cyclones occurring anywhere around the absolute terms to the total existing which the Dominican Republic is world, and allows future events to value of the current residential also prone. Buildings that are more be quickly analyzed and losses to stock in the Dominican Republic. structurally sound are likely to be more easily determined, both in In 1930, the value of the total better withstand high winds as well the residential and nonresidential residential and nonresidential stock as strong ground motion. However, sectors. was $110 million in 1935 dollars; it should be noted that within a today, it is over $150 billion. given type of construction, such as San Zenon was a deadly outlier in unreinforced masonry, vulnerability a season that yielded just three The damage from the 1930 storm remained the same. storms. In 2017, there were 17 was estimated at $18 million in named storms—including Harvey 1935 dollars. If today the same How does this model help? and Irma. The total number of storms storm directly hit the city and in a season is not important. All that moved through the rest of the Home to over 3.5 million people, matters is the one storm that strikes country, it could cost as much Santo Domingo is the most populous your community. Modeling the big as $15 billion. However, taking metro region in the West Indies. storm can help decision makers and into account the value of current The results from remodeling the communities plan for the worst and residential and nonresidential San Zenon Hurricane provide a be prepared. stock, this represents a decline in relative damages—from almost 16 percent of the value of residential exposure damaged in 1930 to 10 THE ANGRY GODS percent today. The word hurricane derives from the Spanish huracán, which comes from Juracán, the name of the storm god of the Carib or Taino people native to the Caribbean There are several possible reasons region. Juracán is believed by scholars to be derived in part from the Mayan creator for the reduction of relative loss. god, Huracan, who created dry land out of the turbulent waters, but who also One may be the change in building destroyed the original “wooden people” of Mayan myth with a great storm and flood. construction practices, particularly The history of the region is punctuated by such cataclysms: in 1502, the new city of since 1980. That was the year Santo Domingo was completely destroyed by a hurricane, and was then rebuilt on when a new building code was the opposite bank of the Ozama, which flows through it today. introduced to prevent serious damage from earthquakes, to Aftershocks 47 WHEN THE RIVERS RISE Thailand Floods, 2011 48 Aftershocks “The temple bell stops. But the sound keeps coming—out of the flowers” —Basho, 17th-century Buddhist poet Aftershocks 49 Flood on Vibhavadi Rangsit Road, Thailand. Photo: © Prakasit Chunphaiboon | Dreamstime.com The Thailand floods in 2011 exposed the vulnerability of global industries to local disasters, and highlighted the importance of Thailand in the global supply chains of the automobile and electrical hardware industries. Risk models could help businesses assess their resilience to such disruptive events, and help governments decide on flood mitigation strategies. Arising at the confluence of provinces in the North, Northeast, Thailand’s GDP shrunk by more the Ping and Nan Rivers, the and Central regions as rivers burst than 10 percent in the final quarter Chao Phraya, Thailand’s major their banks. The basins of the of 2011. The event also became the watercourse, flows 372 km south Mekong and Chao Phraya were largest Asian flood re/insurance before finding its way through particularly affected, and flooding catastrophe; according to the Bangkok to the Gulf of Thailand. in the Chao Phraya basin was reinsurance company Munich Re, Many of the country’s largest potentially exacerbated by flood $18 billion in losses was declared and most densely populated management practices, specifically due to the significant flood damage cities lie along its banks. It is major releases of water from the experienced by industrial estates the principal watershed for 35 Bhumiphol and Sirikit dams. A along the banks of the Chao percent of the nation’s land and significant amount of damage Phraya. home to 40 percent of Thailand’s occurred in areas that were citizens, employing 78 percent of protected by dikes that failed. Prior to the 2011 floods, the its workforce; the regions it runs insurance industry did not consider through generate 56 percent of the Local losses, global Thailand to be a major source of country’s GDP. When it floods— consequences disaster risk. There was also little as it often does, in a country awareness of how production with rainfall of over 1,400 mm The disaster affected more than 13 disruptions in Thailand could affect annually—vast areas of the country million people in Thailand and left the global supply chain. The flood are affected. many neighborhoods underwater event exposed the vulnerability of for months. Residential, global industries to local disasters, However, the floods of 2011 were commercial, and industrial sites and highlighted the importance the worst that Thailand had were badly affected, and the World of Thailand in the global supply experienced in decades. Caused by Bank estimated total financial chains of the automobile and heavier-than-usual monsoon rains losses of around $46.5 billion, electrical hardware industries, and a spate of tropical storms from making the floods the world’s which experienced considerable July through November, flooding fourth most expensive disaster disruption when factories and quickly spread and affected at that time. It is estimated that warehouses were flooded for 50 Aftershocks include soil moisture (and events in JBA Risk Management other antecedent conditions), Pte. Ltd.’s Thailand flood model terrain characteristics (including represents an approximation of Chiang Mai gradient), and water and the 2011 Thailand floods. This land management practices scenario considers meteorological related to dams, reservoirs, and and antecedent conditions similar Khon Kaen urbanization. Longer-term weather to those associated with the 2011 Ubon patterns are also critical. During a event, but with a wider spatial Ratchathani La Niña, the cold phase of the El extent of flooding, including Nakhon Niño Southern Oscillation (which Thailand’s Central, Northern, and Ratchasima persisted through much of 2011), Eastern provinces (e.g., Udon Bangkok an atmospheric phenomenon Thani, Khon Kaen). It also factors called the Walker Circulation in the mitigating effects of known shifts farther west, aided in part flood defenses. by the stronger-than-normal northeasterly trade winds. This The model predicts that a similar strengthens the monsoonal rains event today would cause economic Gulf of Thailand over Thailand. Since August 2010, losses in the range of $60–80 Thailand had received on average billion, with insured losses of 33 percent more precipitation $20–28 billion. Less certain is the annually than is typical; as a likelihood of a similar event: this Hat Yai result, the soil had become scenario has an annual probability saturated and had exceeded of occurrence of between 1 percent Flooded Area Low n n n n n High its capacity to absorb further and 0.5 percent—or a so-called High Low of the 2011 flooding Flooded Area Extent in Thailand. Map: moisture. Although Thailand is return period of 100 to 200 years. JBA, Axis Maps seldom affected by strong typhoon An important contribution to winds, the rains from tropical the uncertainty lies in the flood cyclones affecting the neighboring management of the event—for several weeks. The global insurance countries of Vietnam, Cambodia, example, the releases of water from market was dominated in 2011 and the Lao People’s Democratic the Bhumiphol and Sirikit dams. by insured losses—apportioned Republic often sweep across the to both business interruption and country—particularly during a Thailand may well experience contingent business interruption— strengthening La Niña. All of similar events in the future, with from the floods in Thailand and the these factors make predicting the similarly disruptive consequences Tohoku earthquake in Japan. likelihood and extent of flooding globally. Risk models can help particularly challenging. businesses anticipate the impacts Uncertain predictions of such events, and can help Modeling flood hazards is difficult, governments prepare effective Flooding is a highly complex but this does not mean we should mitigation strategies. phenomenon, contingent on not try; a flood scenario taken an interplay of factors. These from the catalog of synthetic Aftershocks 51 Photo: © Stockbyte THE SCARY WIND Typhoon Wanda, Zhejiang, China, 1956 A remodeling of Typhoon Wanda, which devastated China’s Zhejiang Province in 1956, provides a clear illustration of how development can lead to potentially more costly disasters. Aftershocks 53 In early August 1956, Typhoon Development in risk-prone areas hazard-prone areas drives up Wanda made landfall in eastern increases exposure, and it follows disaster risk in absolute terms. The China near the city of Zhoushan, that the damages from a similar dramatic growth of the Zhejiang 250 km south of Shanghai. It hazard today would be costlier. region has exposed ever greater weakened slowly as it proceeded To estimate the potential impacts amounts of property, of ever higher northward through inland China of such an event, AIR Worldwide value, to typhoon wind and flood. and dissipated four days later. modeled the typhoon winds and This trend is repeated wherever we Along the coast of Zhejiang inland flooding resulting from a see urban growth across the world. Province, Wanda produced a 5 storm whose strength and track m storm surge that destroyed resembled Wanda’s (storm surge Location is a key factor in growth almost 500 seawalls, sank over was not modeled). The impact on in modeled damage. Other things 900 boats, and damaged a further residential and commercial building held equal, buildings further from 2,233. The storm also flooded crop stock was modeled for three the coastline will be less affected fields, destroying 20,380 tons of different years: 2006, 2012, and by coastal winds and storm surge wheat. Across Zhejiang, 2.2 million 2018. The 2006 building stock was than buildings nearer to the houses and nearly 40 percent of based on AIR’s industry exposure coastline. Property located close to the main roads were damaged database (IED). The modeled rivers or in low-lying areas will be during the storm. Ten sections of damage to the 2006 building stock more prone to flood from typhoon- the Zhejiang–Jiangxi railway line was $4.2 billion (in 2006 dollars). related rainfall than property on washed away. Nationwide, Wanda Values for 2012 and 2018 were high ground. However, there are killed over 4,900 people and injured extrapolated from the 2006 values other factors—exacerbating or over 16,500. using AIR’s IED for China to account mitigating—not considered in this for inflation and changes in China’s modeling exercise. Engineering A similar typhoon in Zhejiang capital stock of buildings. With the advances over several decades today would find a region in the adjustments to building exposure, can result in improved building midst of social and economic the total modeled damage to design standards and construction change. Host to the G20 summit buildings in 2012 was $11.5 billion practices. As the population in 2016, the province is home to (2012 dollars); for 2018, the figure becomes wealthier, a greater over 55 million people, and in was $26.8 billion (2018 dollars). If proportion of building stock is built 2017 recorded GDP growth of 7.8 one corrects for inflation, the 2006 to better standards, reducing the percent. Businesses like Alibaba loss in 2018 dollars would be around vulnerability of some buildings. are based in the provincial capital $5.7 billion. Early warnings can help minimize Hangzhou, and the city of Ningbo the loss of life from a typhoon has the world’s busiest port by While the economic damage in affecting land. For example, the throughput tonnage. The Ningbo 1956 has not been quantified, Shanghai meteorological services Free Trade Zone is home to over the change in value over a single and capacity for impact-based 6,600 companies representing 60 decade makes clear that the forecasts and early warnings are countries and concentrated in area has seen a rapid increase in among the best in the world and three main industries: international building values exposed to typhoon serve as an example to many trade, advanced manufacturing, hazard. This increase underlines countries striving to reduce their and warehousing and logistics. the fact that development in hydrometeorological disaster risk. 54 Aftershocks Track of Typhoon Wanda, 1956, Seoul showing wind speed in knots. Tokyo Map: IBTrACS, Axis Maps Ōsaka Wuhan Shanghai East China Chongqing Sea plans, and support and training of communities in making homes and Taipei Philippine businesses more resilient to the Sea Guangzhou effects of typhoon, storm surge, Hong Kong and floods. The location of critical infrastructure (such as water South China Sea and waste treatment plants), and storage of hazardous chemicals Wind Speed 30 50 Manila 80 100 130 160 should be taken into account, to avoid secondary impacts like In typhoon-prone areas high value and high population contamination and illness. experiencing rapid urban growth, or intensive use) should either such as Zhejiang Province and be avoided or be constructed to Such systems and techniques are other areas of coastal China, it withstand the effects of hazards largely in place in China, and have is important to implement risk- locally present. This may be no doubt reduced vulnerability in informed land use planning when achieved through adherence many cases since Typhoon Wanda considering significant investment to design and construction occurred, but in rapidly developing and development. That is, standards, investment in storm high-hazard areas, the importance development in the highest-risk surge protection, use of early of integrating risk management areas (particularly those with warning systems and evacuation should not be underestimated. THE EARLIEST RECORDS The entirety of China’s long history has been punctuated by the annual arrival of typhoon season. In around 450 AD, the author Shen Huai-yuan wrote the earliest known description of typhoons. “Many jufeng (typhoons) occur around Xi’an County. Ju is a wind that comes in all four directions. Another meaning for jufeng is that it is a scary wind. It frequently occurs in the sixth and seventh month. Before it comes, roosters and dogs are silent for three days. Major ones may last up to seven days. Minor ones last one or two days. These are called heifeng (black storms) in foreign countries.” Some 400 years later, the first official record of a typhoon’s landfall— near the city of Mizhou, now named Gaomi, in Shandong Province—was documented in the official history of the Tang Dynasty. “On the 15th day of the 8th month of the 11th year of Yuanhe Reign,” wrote the unnamed author, “Mizhou reported that a typhoon occurred and the seawater damaged the city wall.” No detailed account of the damage was given, unfortunately, making remodeling of this unnamed storm impossible. Tang Dynasty fresco. Photo: Thinstock.com Aftershocks 55 Solar flare captured by NASA’s Solar Dynamics Observatory. Image: NASA/SDO RETURN OF THE BLACK SWAN The Carrington Event, 1859 Not all disasters are earth-based. A solar storm like the Carrington event of 1859 could produce widespread damage on an unimaginable scale; risk modeling could help mitigate its effects. Aftershocks 57 In the morning hours of Thursday, lines sparked, causing paper fires in able to collect a wealth of accurate September 1, 1859, the British some telegraph offices and shocking data on it. astronomer Richard Carrington operators through their handsets. was taking routine observations A real threat of sunspots, with the image of the The event was brief—Carrington solar surface projected from his left for a minute to call someone to The chances of a direct hit by a telescope onto a sheet of coated witness it with him, and by the time Carrington event are as high as glass, when his attention was caught he returned it was all but over—but 12 percent in the next 10 years, by something unusual. its effects were global, and dramatic. according to physicist Pete Riley of If the same event happened today, its Predictive Science Inc., who in 2014 “Two patches of intensely bright effects on power grids, computers, analyzed records of solar storms going and white light broke out,” he and all the systems that depend on back 50-plus years, extrapolating wrote in his report, “Description of them would likely be catastrophic on the frequency of ordinary storms to a Singular Appearance Seen in the the extreme to calculate the odds. a scale it is difficult to imagine, much Sun,” for the Monthly Notices of What would the likely effects of less quantify. While no remodeling the Royal Astronomical Society. such a storm be? “What’s at stake,” of the Carrington event has been “My first impression was that by says Tom Bogdan, director of the conducted, it is possible to infer from some chance a ray of light had Space Weather Prediction Center various studies the likely effects of a penetrated a hole in the screen in Colorado, “are the advanced similar event in today’s world. attached to the object-glass, by technologies that underlie virtually which the general image is thrown every aspect of our lives.” Magnetic disturbances caused by into shade, for the brilliancy was CMEs are measured in nano-Teslas fully equal to that of direct sunlight. Modern life is powered by (nT) according to a parameter called But, by at once interrupting the interconnected energy grids, Dst, short for “disturbance—storm current observation, and causing managed by computers. Most time.” Modern estimates put the the image to move … I saw that I communications devices are Carrington event at around -850 was an unprepared witness of a very integrated with the global GPS nT on this scale. The most recent system, reliant on geostationary different affair.” disruptive event, a magnetic storm satellites. In the event of a major The phenomenon Carrington in 1989 that knocked out the power solar storm, X-rays and extreme observed was a solar storm, of the grid across Quebec for 12 hours, UV rays would reach earth almost sort which releases a combination measured -589 nT. And a CME event immediately, causing radio blackouts of radiation, charged particles, and that almost hit earth in July 2012 was and GPS navigation errors. The coronal mass ejections (CMEs) estimated to measure -1,200 nT, 40 charged particles could damage of magnetized plasma into space. percent stronger than the Carrington the circuits of satellites, knocking In the days after the event, storm. Fortunately, the area of the out the GPS system and major geomagnetic storms caused by sun on which the flare occurred was communications networks, including the CMEs ignited a spectacular pointing away from the earth at the those responsible for credit card display of the aurora borealis—the time of the storm. While the event payments. Finally, the CME, which northern lights—that was visible as missed the earth, it did hit a space- takes a day or more to reach the far south as the tropics. Telegraph based solar observatory, which was earth, could cause the failure 58 Aftershocks of anything using or producing expensive upgrades to the grid. In a disaster. Richard Carrington electricity, from household the meantime, detailed models of a described himself as “an unprepared appliances to transformers in Carrington-scale event would be a witness”; in today’s connected electrical grids. In a world where good start to mitigation efforts. world, with the earth wrapped in a everything is reliant on the grid— fragile cocoon of power grids and including, for example, water supply Space weather, like any other communications technology, being systems and the food supply chain— hazard, needs only human unprepared is a luxury we cannot the potential for immediate and intervention or inaction to become allow ourselves. widespread chaos is massive. The cost of replacing transformers in the United States alone is estimated at between $0.6 trillion and $2.6 trillion. Damage to satellites is likely to cost between $30 billion and $70 billion. With these sorts of projected losses, the cost to the global economy is incalculable—and a recovery period of 4 to 10 years is likely. Mitigating the risk Better forecasting of a solar event could provide better outcomes. Current technologies are able to provide only about a day’s notice of the arrival of a CME—putting the prediction of space weather about 50 years behind the science of meteorology. However, this window still provides enough time to mitigate some of the damage. For example, power companies could take transformers offline before the storm struck, protecting them and producing shorter, local blackouts rather than long-lasting damage. Longer-term measures would include Solar Dynamics Observatory at NASA’s Goddard Space Flight Center in Greenbelt, Md. Photo: NASA Aftershocks 59 Image: © Noiral | Dreamstime.com MODELING THE FUTURE From Statistics to Stories to Action Aftershocks 61 “The best qualification of a prophet is to have a good memory. “ —The First Marquess of Halifax Over the last three decades, as countries, with settlements growing such advances. Some use machine science and technology continue in harm’s way, and the most learning to develop and market to develop, we have witnessed a vulnerable people continuing to site-specific exposure data for every tremendous growth in the field of build and live in new non-engineered building in the United States. Others risk modeling. Scientists have made houses. The disasters of 2017—from use machine learning to develop great progress in quantifying risk for severe hurricanes, to forest fires novel approaches for use in new almost all natural hazards, including and the ensuing mudslides—have types of risk models. risk from flooding, earthquake provided ample evidence of this ground shaking, high winds, coastal increasing vulnerability, in both It’s also the case that more traditional flooding due to tsunami or extreme developed and developing countries. approaches to risk modeling are storms, and a whole suite of volcanic being applied to new perils and to hazards. At the same time, we have entered previously unmodeled regions. These a golden age for data collection, efforts are particularly important At the same time, engineers have analysis, and sharing. Data can be for the developing world, which has been attempting to introduce more collected in new ways: through lagged behind developed countries in advanced construction regulations community mapping efforts, by risk modeling. in the form of building codes street cameras mounted on cars, and to develop flood and coastal or by drones, aircraft, and a variety As illustrated in this publication, protection solutions, while planners of satellites. Advances in cloud results from risk models can be used and geographers have focused their computing and machine learning to inform disaster risk management energies on mapping out areas at have made it possible to host and planning—in the development of risk. With the growing appreciation analyze copious amounts of data financial products, in improved and that development should be risk- using approaches that have been better-enforced building regulations, informed, social scientists have developed only in the past few years. and for planning purposes. Some developed methods and tools to Inexpensive cell phones, social of the events described in these understand social processes and media, and other means of electronic pages provide lessons that may be vulnerabilities. One positive result communication provide novel has been a tentative trend toward methods for sharing risk results. Risk applied locally to reduce the impact lower global risk to life from seismic modelers are challenged to leverage of an extreme event—for example, ground motion. this progress by improving their the implementation of earthquake- models and data sets. resistant building codes by a city Other types of hazard have or regional government, or crop not followed this trend: rapidly These advances have prompted the diversification by farmers in an area increasing coastal populations have development of new approaches prone to flooding. Others, like a revealed vulnerabilities to coastal to collecting risk-related data and Tambora-scale eruption or another and hydrometeorological hazards, novel methods for estimating risk. Carrington event, have global for example. Rapid urbanization has New private sector companies have implications and require a global continued unabated in developing already been formed to exploit response in anticipating massive 62 Aftershocks disasters and building resilient deployment of every tool in the effort. Its goal was to offer stories systems. disaster risk management tool box— of past disasters, and explore their from the technologies of the present implications for the present, in an The combination of urbanization and and the future, to the illuminating interesting and accessible way. We climate change will be marked by and instructive lessons of the past. hope readers have gained a new an intensification in the frequency understanding of risk. We hope and severity of hydrometeorological An important area where work further that their knowledge will hazards, with a dramatic increase remains to be done is in engaging inform future discussions and actions in loss potential, especially in areas non-practitioners, in part by related to disaster risk management, of increased social vulnerability communicating risk—and steps and ultimately contribute to a less or increased urban density and aimed at reducing risk—in an risky future. industrialization. The resulting understandable and actionable challenges will require the way. This publication is part of that Aftershocks 63 BIBLIOGRAPHY Adler, D. “The Mexico City Earthquake, 30 Years https://news.nationalgeographic.com/ AIR-Currents/2012/The-2011-Thai-Floods- On: Have the Lessons Been Forgotten?” news/2011/03/110302-solar-flares-sun- -Changing-the-Perception-of-Risk-in- The Guardian, September 18, 2015. storms-earth-danger-carrington-event- Thailand/. Alden, A. “The Great 1815 Tambora Eruption: science/. Terazoko, E. “Crop Uncertainty Drives Vanilla What If This Volcano Blew Today?” KQED Luterbacher, J., and C. Pfister. 2015. “The Year Price Back to Record Level.” Financial Science, April 9, 2015. https://www.kqed. without a Summer.” Nature Geoscience 8, Times, March 25, 2018. https://www. org/science/29080/the-great-1815-tambora- no. 4 (April 2015): 246–48. ft.com/content/1c810c2a-286f-11e8-b27e- eruption-what-if-this-volcano-blew-today. Masters, J. “Hurricanes and Climate Change.” cc62a39d57a0. AON Affinity Marketing and Communication. Weather Underground. 2013. https://www. ———. “Vanilla Price Reaches Record High after “Krakatoa Eruption, 1883.” 2008. wunderground.com/climate/hurricanes-and- Madagascar Cyclone.” Financial Times, climate-change. April 24. 2017. https://www.ft.com/content/ Berlonger, J., M. Castillo, and R. Sanchez. “Mexico’s Strongest Earthquake in a Ndukong, K. H. “Zhejiang Province Is China’s e0e2fc16-28db-11e7-bc4b-5528796fe35c. Century Leaves Dozens Dead.” CNN, Economic Powerhouse.” People’s Daily, Watkins, T. “Problems with Haiti Building September 9, 2017. https://www.cnn. October 16, 2017. http://en.people.cn/ Standards Outlined.” CNN, January 13, com/2017/09/08/americas/earthquake-hits- n3/2017/1016/c90000-9280210.html. 2010. http://www.cnn.com/2010/WORLD/ off-the-coast-of-southern-mexico/index. Oxford Economics. “The Economic Impacts of Air americas/01/13/haiti.construction/index. html. Travel Restrictions Due to Volcanic Ash.” html. The Economist. “Destruction in Chile.” February May 1, 2010. https://www.oxfordeconomics. Wayman, E. “Chile’s Quake Larger but Less 8, 2010. https://www.economist.com/ com/my-oxford/projects/129051. Destructive than Haiti’s.” Earth Magazine, node/15591569. Padgett, T. “Chile and Haiti: A Tale of Two March 1, 2010. https://www.earthmagazine. ———. “Why There Is a Worldwide Shortage Earthquakes.” Time, March 1, 2010. org/article/chiles-quake-larger-less- of Vanilla.” March 28, 2018. https:// http://content.time.com/time/world/ destructive-haitis. www.economist.com/blogs/economist- article/0,8599,1968576,00.html. Willis Towers Watson. “Mount Vesuvius Eruption explains/2018/03/economist-explains-4. Phillips, T. “Near Miss: The Solar Superstorm of Could Cause 21,000 Casualties, Economic Evans, R. “Blast from the Past.” Smithsonian July 2012.” NASA. July 23, 2014. https:// Losses of $24 Billion.” Business Wire. science.nasa.gov/science-news/science-at- Magazine, July 2002. April 15, 2015. https://www.businesswire. nasa/2014/23jul_superstorm. Hurricanes: Science and Society. “1930– com/news/home/20100415006327/en/ Reinoso, E., M. A. Jaimesa, and M. A. Torresa. Mount-Vesuvius-Eruption-21000-Casualties- Dominican Republic Hurricane.” http:// “Evaluation of Building Code Compliance in Economic-Losses. www.hurricanescience.org/history/ Mexico City: Mid-rise Dwellings.” Working storms/1930s/DominicanRepublic/. World Bank Social, Urban, Rural and Resilience paper, Universidad Nacional Autonoma de JBA Risk Management. “Thailand River Flood Global Practice (GSURR) Disaster-Resilience Mexico (UNAM), 2015. Scenario.” 2018. Analytics and Solutions KSB. “Estimation Rice, J. “Mexico City Scars Remain from 1985’s of Economic Losses from Tropical Cyclone Jongman, B., P. J. Ward, and J. C. J. H. Aerts. Devastating Earthquake.” Los Angeles Enawo.” (Washington, DC: World Bank “Global Exposure to River and Coastal Times, September 24, 1995. http://articles. Group, 2017). https://reliefweb.int/report/ Flooding: Long Term Trends and Changes.” latimes.com/1995-09-24/news/mn-49374_1_ madagascar/estimation-economic-losses- Global Environmental Change 22, quake-victims-mexico-city-temblor. tropical-cyclone-enawo.  no. 4 (2012): 823–35. doi:10.1016/j. Simpson, A., S. Balog, S. Fraser, B. Jongman, and gloenvcha.2012.07.004. ———. “Review of Historical Disaster Scenario: K. Saito. 2016. The Making of a Riskier Armenia 1988 Earthquake.” Unpublished. Kemp, J. “Time to Be Afraid—Preparing Time for Future (Washington, DC: World Bank the Next Big Solar Storm.” Reuters, July World Bank, Washington, DC. Group, 2016). 25, 2014. https://www.reuters.com/article/ ———. “Review of Historical Disaster Scenario: Simpson, A., R. Murnane, K. Saito, E. Phillips, us-electricity-solarstorms-kemp/time-to- Chile 2010 Earthquake.” Unpublished. World and R. Reid. Understanding Risk in an be-afraid-preparing-for-the-next-big-solar- Bank, Washington, DC. Evolving World. (Washington, DC: World storm-kemp-idUSKBN0FU20Q20140725. ———. “Review of Historical Disaster Bank Group, 2014). Klingaman, W. K., and N. P. Klingaman. The Year Scenario: Dominican Republic 1930 Sobradelo, R. “Volcanic Risk: Separating the Facts without a Summer (London: St. Martin’s Hurricane.” Unpublished. World Bank, from the Hype.” Willis Towers Watson Wire Press, 2013). Washington, DC. (blog). September 28, 2017. https://blog. Lloyd’s. “Solar Storm Risk to the North American willis.com/2017/09/volcanic-risk-separating- ———. “Review of Historical Disaster Scenario: Electrical Grid.” Lloyds Atmospheric and the-facts-from-the-hype/. Haiti 2010 Earthquake.” Unpublished. World Environmental Research. 2013. Sousonis, P. “The 2011 Thai Floods: Changing Bank, Washington, DC. Lovett, R. A. “What If the Biggest Solar the Perception of Risk in Thailand.” ———. “Review of Historical Disaster Scenario: Storm on Record Happened Today?” AIR Worldwide. April 19, 2012. http:// Indonesia 1815 Volcanic Eruption.” National Geographic, March 4, 2011. www.air-worldwide.com/Publications/ Unpublished. World Bank, Washington, DC. 64 Aftershocks ABBREVIATIONS AND ACRONYMS ARC African Risk Capacity IED industry exposure database BNPB National Disaster Management Authority (Indonesia) KSB Knowledge Silo Breaker BPBD Local Disaster Management Agency (Banda Aceh, Indonesia) MMI Modified Mercalli Intensity scale CENAPRED National Center for Prevention of Disasters (Mexico) nT nano-Tesla CME coronal mass ejection PDNA post-disaster needs assessment DEM digital elevation model REKOMPAK community-based approach for large-scale reconstruction and D-RAS Disaster-Resilience Analytics and Solutions rehabilitation ERN Evaluación de Riesgos Naturales SASMEX Mexican Seismic Alert System GDP gross domestic product SINAPROC National System for Civil Protection (Mexico) GFDRR Global Facility for Disaster Reduction and Recovery TEV total exposed value GPS Global Positioning System UNISDR United Nations Office for Disaster Risk Reduction HURDAT National Hurricane Center Hurricane Database USGS United States Geological Survey IBC International Building Code VEI Volcanic Explosivity Index