USA Expenditures on Extreme Weather Events

The USA's National Climatic Data Center (NCDC) has published a list of all of the extreme weather events that have occurred within the past three decades or so that the US government has spent more than $1 billion USD in damages on (adjusted to the 2011 dollar). While conclusions should not be reached based on such crude data, the simple numbers can be interesting to observe. For example, from 2006-present there have been over 40 extreme weather events that have necessitated over $1 billion in damages. Between 1995 and 1990, there were 19 such events, and between 1985 and 1980, there were 8. The complete data can be found at: http://www.ncdc.noaa.gov/oa/reports/billionz.html. 

IPCC's SREX

Recently, the Intergovernmental Panel on Climate Control (IPCC) published its Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX). In it, the body outlined the results of simulations to predict how extreme weather events might be affected in the future due to anthropogenic climate change, as well as other natural weather variations. It also outlines how global institutions should respond to these projected events, and how we as a human population can prepare ourselves for dealing with them. The IPCC concedes that it is incredibly difficult to make any definite conclusions, and sites the lack of extreme weather event data as a source of possible misinterpretations of their projected frequency and intensity. However, they did manage to point out a few areas in which anthropogenic climate change is “very likely” (90-100% probability) or “likely” (66-90% probability) to affect extreme weather events. It is likely that we will see a global trend of increased precipitation, as well as extreme coastal high water due to rising sea levels. There will also likely be longer, more frequent, and more intense heat waves, going along with the conclusion that some areas might see more intense droughts. The IPCC is very certain that there will be a marked increase in minimum and maximum daily temperature extremes by the end of this century. They found it very likely that, therefore, there will be an overall decrease in the number of cold days and nights and increase in warm days and nights. What I found most striking about this report, however, was its claim that extreme weather events that might now be a 1 in 20 year event might become a 1 in 10 or 1 in 5 year event. 

Source:

Intergovernmental Panel on Climate Change, "Special Report on Managing the Risks of Extreme Weather Events and Disasters to Advance Climate Change Adaptation." Can be found at: http://ipcc-wg2.gov/SREX/images/uploads/SREX-SPM_Approved-HiRes_opt.pdf

El Niños and Global Warming

It is well established that the El Niño phenomenon is not a result of global warming. The El Niño/La Niña periodical warming and cooling phenomenon is part of a natural climate pattern that causes extreme weather events such as floods and droughts. The question now is, has climate change affected the intensity and/or frequency of these events? Some studies suggest that the recent increase in El Niño (warming) events as compared to La Niña (cooling) events cannot solely be described by natural cycles (Trenberth, 1997). However, it is important to note that many of these studies are conducted using evidence from only about 100 years prior, which is in all likelihood not an adequate amount of elapsed time after which to attempt to suggest anomalies in the data. It has been suggested that El Niño events are changing due to the already rising SSTs that can perhaps be attributed to anthropogenic climate change. However, this begins a which came first scenario: El Niño and wind speed changes help create SST patterns, and higher SSTs themselves can enhance the El Niño effect. Scientists are well on their way towards proving that rising SSTs can be linked at least partially to climate change. Its possible effect on El Niño events are an interesting subject that has yet to be adequately researched. 

Snow in New York

Just a quick article I stumbled upon while checking up on weather conditions back home across the pond...

http://www.nytimes.com/2010/02/11/science/earth/11climate.html