The headline so far
The region is running both hot and cold.
Average annual temperatures have alternated between warm and cool periods through much of the past century. Warming peaked in the 1930s and '40s, cooled somewhat from the 1960s to 1970, then warmed to 2 degrees F. above levels of the 1970s. Numbers of days above 90 degrees and nights above 75 degrees have increased. In the Southeast, daily and five-day average rainfall has increased, with the heaviest storms dumping 27 percent more water in 2012 than in 1958. In some places summers have become more dry, while in others they are more wet. The number of most-intense tropical cyclones has increased in the Atlantic Basin since 1980, but researchers are still trying to untangle the contributions from human-triggered climate change versus natural climate swings.
Look-ahead
Temperatures are expected to increase this century by 4 degrees F. to 8 degrees F., depending on emissions trends, with temperatures running about 1 degree cooler along the coasts. The number of 95-degree days is expected to rise, and the number of freezes is likely to fall. This could affect some fruit crops if milder winters prompt fruit trees to flower too early, leaving them vulnerable to a late-season freeze. Rainfall is harder to predict, although the western part of the region appears headed for drying, while the northeastern-most areas could see increased rainfall. The Caribbean is likely to see decreasing rainfall on average. Although the number of tropical cyclones is expected to decline, more of those that occur are expected to be among the strongest. Sea-level rise is expected to increase the vulnerability of low-lying areas to tropical-cyclone storm surges. Vast sections of the Southeast are expected to see water resources dwindle from a combination of climate change and population growth.
What's being done?
To adapt, Georgia’s Clayton County has been recycling wastewater through specially built wetlands to provide additional filtering and then storing the filtered water in county reservoirs. The county also has adopted water-saving leak-detection and efficiency programs. During the 2007-08 drought, Clayton County's reservoirs remained at near capacity while Atlanta's main source, Lake Lanier, reached record lows. Miami and Miami-Dade County are using sea-level projections to underpin plans for handling storm water, improving infrastructure, and for emergency management. Of the 11 states in the Southeast, only Florida has greenhouse-gas emissions targets, and two have adaptation plans. The 11 are Louisiana, Arkansas, Mississippi, Alabama, Florida, Georgia, Tennessee, Kentucky, North Carolina, South Carolina, and Virginia.
