Climate Fact: National Annual Precipitation Trends (Arizona)
Most areas of the United States are now receiving more total annual rainfall than they did 50 years ago. There is significant regional variability in this trend, however. Adding up the total regional positive and negative trends, the U.S. as a whole is now receiving five percent more precipitation each year. The Northeast and northern Midwest have shown the greatest increases in average annual rainfall, with the Southeast and Southwest exhibiting the greatest rainfall reduction trends. Some of the Nation’s most pronounced rainfall reduction trends have occurred in Arizona. While most of the state has experienced around five percent reduction in annual rainfall levels, parts of the southwest corner of the state have witnessed as much as a 40 percent drop.
To see how average annual precipitation has changed in your local area since the 1950′s, visit http://www.earthgauge.net/climate-facts-image-library#8. This image is featured in the “Global Climate Change Impacts in the United States” report recently published by the U.S. Global Change Research Program. The image is in the public domain.
Seasons: Winter, Spring, Summer, Fall
Source: Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson,(eds.). Cambridge University Press, 2009
