Sandy the 11th U.S. billion-dollar disaster of 2012

Devastating Hurricane Sandy was the eleventh billion-dollar weather-related disaster in the U.S. so far this year, and the most expensive, said insurance broker AON Benfield in their November 8, 2012 Catastrophe Report. This puts 2012 in second place for most U.S. billion-dollar weather disasters behind 2011, when NOAA's National Climatic Data Center (NCDC) counted fourteen such disasters. AON Benfield rated seventeen events as billion-dollar weather disasters in 2011, so the actual number of such disasters has considerable uncertainty depending upon who is doing the estimates. NCDC has not yet released their official figures for 2012's billion-dollar weather disasters, and we might expect that their total could be 20% lower than AON Benfield's, judging by what happened in 2011. This would give 2012 nine billion-dollar weather disasters, which would still put 2011 in second place for most billion-dollar weather disasters. Although damages due to weather-related disasters are increasing, we cannot yet say climate change is to partially to blame. There are too many other complicating factors such as increases in wealth and population that may be responsible for the rise in damages, and there is too much noise in the data to see the signal of climate change, as I explain in my January 2012 post, "Damage losses and climate change". We are better off looking at the atmosphere itself to find evidence of climate change, and there are plenty of examples of that--such as the record loss of Arctic sea ice this summer.


Figure 1. The escalators down to the South Ferry subway station in Lower Manhattan's Financial District lie flooded in the wake of Hurricane Sandy's storm surge on October 29, 2012. Total economic damage from Hurricane Sandy has been estimated at $30 - $50 billion by EQECAT. Image credit: New York MTA and Associated Press.


Figure 2. The U.S. has experienced eleven weather-related disasters costing at least $1 billion in 2012, according to data taken from the AON Benfield October 2012 Catastrophe Report. AON Benfield has not made a damage estimate for the 2012 Midwest drought, but according to National Crop Insurance Services, crop insurance losses alone will total $20 billion. The total cost of the drought could be more than $77 billion, said Purdue University economist Chris Hurt in August. As Nick Sundt of the WWF summarizes in a nice blog post, this year will probably be the second most costly year since 1980 in terms of billion-dollar weather-related disasters.


Figure 3. Number of weather-related U.S. billion-dollar disasters per year (blue bars) from 1980 - 2012, and the total cost of these disasters (red and dark blue lines, with the red line showing the inflation-adjusted costs.) Image credit: NOAA's National Climatic Data Center (NCDC)

Winter Storm Brutus bringing blizzard conditions to Montana
Winter Storm Brutus is bringing blizzard conditions to Northeast Montana, with heavy snow and high winds that have gusted to 45 mph. Brutus has dumped a widespread area of 4 - 6 inches of snow over large portions of Montana since Thursday afternoon, with 7 - 10 inches reported in the Great Falls area and 17" in the mountains near Glacier National Park. According to the Glasgow, MT NWS Facebook page, the current storm has the potential to be a top-ten snowfall event for the area, with records going back 115 years. The storm will affect Montana and western North Dakota through Saturday morning, then push north-northeastwards into Canada.

Top ten 2-day snow events in Glasgow, Montana history:

1 15.0" 4/18/1896
2 14.3" 12/27/2003
3 14.1" 4/ 3/1940, 4/ 2/1940
5 14.0" 11/19/1941
6 13.4" 10/13/2008
7 13.3" 11/ 6/2000
8 13.0" 10/12/2008, 4/ 9/1995, 1/26/1916

The Atlantic hurricane season is not over yet
There are still three weeks left in the Atlantic hurricane season, and the way this year has gone, I wouldn't be surprised to see the season's 20th named storm--Tropical Storm Valerie--sometime this month. One potential candidate is a concentrated area of heavy thunderstorms that has developed about 800 miles west-northwest of the Cape Verde Islands, off the coast of Africa. However, wind shear is a high 20 - 30 knots over the disturbance, and any development should be slow. Our two most reliable models, the GFS and ECMWF, do not develop the disturbance, and show it drifting slowly to the northwest over the next few days. In their 7 am EST Tropical Weather Outlook, NHC gave the disturbance just a 20% chance of developing into a tropical cyclone by Sunday morning.

A better candidate to become Valerie is an area of low pressure that is predicted to develop between Bermuda and Puerto Rico by the middle of next week. The GFS model shows this low becoming a subtropical cyclone as it gets pulled to the north or north-northeast late next week.

Jeff Masters