December 2011 CoreLogic® 2011 Natural Hazard Risk Summary and Analysis Howard Botts, PhD Wei Du, PhD Brady Foust, PhD Thomas Jeffery, PhD Executive Summary 2011 Natural Hazard Risk Summary and Analysis As it has been noted by numerous scientists, risk analysts and other forecasters, 2011 proved to be a record-breaking year for natural catastrophes in the United States and around the world. Hurricanes, wildfires, tornados, earthquakes and various flooding events caused billions of dollars in property damage, put disaster readiness plans and emergency responders to the test in major U.S. urban areas, and resulted in a significant number of lost lives across the country. Now, in addition to reviewing the immediate structural, geographic and financial impact of the past year’s catastrophic events, it’s crucial to consider notable changes in natural hazard incidents as part of a longer-term perspective and evaluate the implications of these trends. One of the most noteworthy statistics to emerge from this annual natural hazard review is that 2011 was the most expensive and the deadliest hurricane season for the U.S. since 2008. Though only three named Atlantic storms made landfall, they caused at least a combined $8 billion in damage, primarily from flooding. In addition, the 2011 tornado season was the third most active since 1980. The 1,559 storms to date this year resulted in the deaths of 552 people, which amount to the combined total number of casualties over the previous ten years. While the 2011 wildfire season continued the trend of having fewer but larger wildfires, there was a significant geographic shift in home losses over the past year from California, which had a cooler and wetter-than-average fire season, to the drought-affected states of Texas, New Mexico and Oklahoma. In fact, total burned wildfire acreage in California was down 90 percent in 2010-2011 compared to 2007-2008. At the same time, the Wallow fire in Arizona burned 469,000 acres and was the largest fire in the state’s history. Also important to note is that two non-western U.S. earthquakes occurred this year in Virginia and Oklahoma – events that startled many residents who believed earthquakes to be strictly a far west U.S. phenomenon. Though in reality earthquake activity in 2011 mirrored the long-running trend of quake concentration in the western U.S., where underlying geology and plate tectonics generate a more active seismic zone, the two unexpected events in the Midwest and Northeast caused a considerable stir among homeowners, insurers and many others affected by the quakes. The CoreLogic Natural Hazard Risk Summary and Analysis provides an overview of the most significant catastrophic natural hazard events that took place in 2011, as well as a brief analysis of potential risk in the coming year and the implications of unexpected changes in natural hazard frequency, intensity and geographic patterns. CoreLogic® 2011 Natural Hazard Risk Summary and Analysis HURRICANES Year in Review This year was the most expensive and deadliest hurricane season since 2008. While only SNAPSHOT three of the 18 named Atlantic Ocean storms struck the U.S. (Hurricane Irene, Tropical While the direct impact Storm Lee and Tropical Storm Don), those storms resulted in at least $8 billion in on New York City from damage and 45 people killed. Much of the property damage associated with the storms Hurricane Irene (a was a result of flooding from intense rainfall as opposed to wind or storm surge flooding. Category 1 hurricane) Overall, 2011 was the seventh most active hurricane season to date in terms of property was ultimately minimal, and life losses since tracking began in 1851. there are some important lessons to be learned from HURRICANE IRENE: The largest and most destructive storm of 2011, Hurricane Irene, this event. The evacuation made landfall over coastal North Carolina on August 27. The storm tracked northward order, affecting 370,000 along the Mid-Atlantic coast (moving over Virginia, Washington, D.C., Maryland, New residents, suggests the Jersey, New York, Connecticut, Rhode Island, Massachusetts and Vermont) causing city lacks confidence torrential rainfall and flooding across much of the northeastern U.S. Especially hard hit in the flood control infrastructure. In fact, were New York, New Jersey and Vermont, which experienced extensive flood damage. New York City does not According to the National Climatic Data Center, the total cost of the hurricane was more have sufficient capacity than $7.3 billion, of which the associated flood damage was about $2 billion. Comparing to defend itself from the flood damage over the past several years with the flood damage from Hurricane Irene (see storm surge associated Figure 1), the flood loss from this single hurricane ranks as the second most expensive in with catastrophic this region. hurricane events, which would be a storm Annual Flood Damage in Northeast and Hurricane Irene classified as Category 2 or 5 greater. With major tunnel and subway entrances only four feet above sea level, even a modest 4 hurricane-driven storm surge would result in Hurricane Irene significant inundation and NC, VA, MD, NJ, NY, CT, RI, MA, VT could easily lead to billions 3 in economic loss. 2 Flood Loss in $billions Flood Loss 1 0 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 Water Year Figure 1 - Comparison of Historical Flood Losses and Irene (1999 hurricane flood losses were the result of Hurricane Floyd, with an estimated $4.5 billion in damages and 56 people killed.) Proprietary and confidential. This material may not be reproduced in any form without expressed written permission. 1 CoreLogic® 2011 Natural Hazard Risk Summary and Analysis TROPICAL STORM LEE: On the heels of Hurricane Irene, Tropical Storm Lee developed from a broad tropical disturbance over the Gulf of Mexico on September 1, 2011. The storm was both large and slow moving, and because of these characteristics, drove heavy rainfall over southern Louisiana, Mississippi and Alabama. The storm then moved north toward the Mid-Atlantic U.S. and unleashed a second outpouring of intense precipitation over Pennsylvania and New York. Figure 2 shows the rainfall map for Tropical Storm Lee, produced by NASA. The satellite imagery clearly shows the five states listed above receiving the greatest amounts of precipitation, with some locations in Pennsylvania and New York accumulating 12 inches of rainfall. Flooding associated with the heavy Tropical Storm Lee precipitation caused significant property damage in the affected areas, estimated to be more than $1 billion. Implications and Projections Given the extent of property damage left in the wake of Hurricane Irene and Tropical Storm Lee, particularly in what might be considered unlikely and underprepared regions of Figure 2 – Precipitation Map the U.S., many risk experts from Tropical Storm Lee feel it’s time to rethink national flood policies around the country and especially in major metropolitan hubs like New York City. There are several key lessons to be taken away from the impact of Tropical Storm Lee, including: ► Large-sized and slow-moving tropical storms originating from the Gulf of Mexico can carry significant precipitation and lead to severe flooding and property damage in the Northeast. ► Short-time intervals between two severe weather systems can exacerbate flooding. Just one week prior to Tropical Storm Lee, Hurricane Irene had soaked the northeastern region of the country. Tropical Storm Lee then poured huge amounts of water on top of the already saturated Northeast, resulting in elevated levels of flooding. ► Property loss associated with flooding from Tropical Storm Lee for the five principal states affected was ranked as the fifth highest based on records over the past 16 years. Even though Lee was not an extreme event, conditions were present that combined to result in extensive damage and destruction. 2 ©2011 CoreLogic, Inc. CoreLogic® 2011 Natural Hazard Risk Summary and Analysis FLOODING Year in Review SNAPSHOT In 2011, there were a number of climate disaster events across the U.S. that each resulted The U.S. Army Corps of in flood losses exceeding $1 billion, according to data from the National Climate Data Engineers opened the Center (NCDC): Morganza spillway in ► Tropical Storm Lee, September 2011, caused an estimated $1 billion in flood Louisiana on May 14, 2011 damage, with particularly severe impact on the states of Pennsylvania and New York. to divert record-high Mississippi River water ► Hurricane Irene, August 2011, caused an estimated $2 billion in flood damage (out levels away from densely of $7.3 billion in total damage). populated metro areas like Baton Rouge and ► In the summer of 2011, the melting of an above-average snowpack across the New Orleans. The spillway northern Rocky Mountains combined with abnormally high precipitation caused was intended to relieve the Missouri and Souris rivers to swell beyond their banks across the upper pressure on downstream Midwest. The resulting flooding caused an estimated $2 billion in losses. levees, sparing hundreds of thousands of homes ► In the spring and summer of 2011, record-breaking rainfall in the Ohio Valley (nearly as well as numerous oil 300 percent over normal precipitation amounts) combined with melting snowpack refineries and chemical caused historical flooding along the Mississippi River and its tributaries. Flood loss plants along the estimates from the Mississippi River inundation are estimated to be $4 billion. Mississippi River. CoreLogic analysis at the time showed that Moving Average Trend Analysis of U.S. Flood Losses many homes in otherwise $50.00 low-risk zones were suddenly in the path of $45.00 Actual Flood Losses floodwaters and that a $40.00 total of 21,272 homes were Moving Average Trend of Flood Losses at risk of being fully or $35.00 partially inundated by the $30.00 floodwaters flowing down from the Atchafalaya $25.00 Basin.