Costliest Weather Events In The United States

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Tropical cyclones are the most costly of the weather and climate disasters. Since 1980, the U.S. has sustained at least 218 weather and climate disasters where overall damages/costs reached or exceeded $1 billion (including Consumer Price Index adjustment to 2017). The total cost of these 218 events exceeds $1.2 trillion. However, this total does not include the costs for Hurricanes Harvey, Irma, and Maria, which are substantial and are still being assessed.

Map of U.S. billion-dollar disasters occurring from January through September 2017

Not including hurricanes Harvey, Irma, and Maria, 35 tropical cyclones have caused at least $583.5 billion in total damages—with an average of $16.7 billion per event. Accounting for just under a fifth (17 percent) of the total number of events, tropical cyclones have caused almost half (47 percent) of the total damages attributed to billion-dollar weather and climate disasters since 1980. These numbers will dramatically rise once the 2017 hurricanes costs are included.

Following tropical cyclones, the most costly event types are:

  1. Drought, with an average cost of $9.4 billion per event
  2. Flooding, with an average cost of $4.3 billion per event
  3. Freezes, with an average cost of $3.4 billion per event
  4. Winter storms, with an average cost of $3.1 billion per event
  5. Wildfires, with an average cost of $2.5 billion per event
  6. Severe storms, with an average cost of $2.2 billion per event

Has every state experienced a billion-dollar disaster?

Every state in the country has been impacted by at least one billion-dollar disaster since 1980While each region of the United States faces a unique combination of weather and climate events, every state in the country has been impacted by at least one billion-dollar disaster since 1980. Over 94 of these disasters have affected at least some parts of Texas, while only one event has impacted Hawaii (Hurricane Iniki in 1992).

Wildfires are most common west of the Plains states and in several Southeastern states. Inland flood events—not caused by tropical cyclones—often occur in states near large rivers or the Gulf of Mexico, which is a warm source of moisture to fuel rainstorms. Drought impacts are mostly focused in the Southern and Plains states where crop and livestock assets are densely populated. Severe local storm events are common across the Plains, Southeast, and Ohio River Valley states. And, winter storm impacts are concentrated in the Northeastern states while tropical cyclone impacts range from Texas to New England but also impact many inland states.

In total, the Central, South, and Southeast regions typically experience a higher frequency of billion-dollar disasters than other regions.

Has the U.S. experienced more flooding events in recent years?

Billion-dollar inland—non-tropical—flood events have increased in the United StatesBillion-dollar inland—non-tropical—flood events have increased in the United States. Most notably, four separate billion-dollar inland flood events occurred in 2016. This doubled the previous record since no more than two of these events had occurred in a year since 1980 until last year.

So far in 2017, two non-tropical inland flood events have affected the country (in California and Missouri/Arkansas). Also, we experienced historic rainfall from Hurricane Harvey, which is tropical-cyclone related flooding. This perhaps should be expected, as heavy rainfall events and their ensuing flood risks are increasing because warmer temperatures are “loading” the atmosphere with more water vapor. Over time, this increases the potential for extreme rainfall events. And, where we build and how we build determines our resilience to the increasing risk of flood events.