Climate Change Impacts
Virginia • Kentucky • Tennessee • North Carolina • South Carolina Georgia • Florida • Alabama • Mississippi • Arkansas • Louisiana • Puerto Rico
The following is a compilation of regional climate change impacts in the Northeast pulled from the Third U.S. National Climate Assessment, Risky Business, and other sources. The Southeast and Caribbean have a combined population of over 80 million and are home to three of the ten fastest-growing metropolitan areas in the United States. This region will see severe effects from climate change, including heat waves and record temperatures, extreme precipitation and storms, and sea level rise.
Record Temperatures
Right Here, Right Now
- Since 1970, the number of days above 95˚F and nights above 75˚F has been increasing and the number of extremely cold days has been decreasing throughout the Southeast.
Projected Trends
- For the Southeast, projected regional average increases are in the range of 4˚F to 8˚F, and from 2˚F to 5˚F for Puerto Rico.
- In the Southeast, an additional 15 to 21 out of 100,000 people are expected to die during this century due to increases in heat-related mortality. This means that 11,000 to 36,000 additional people will die each year if the current population of the Southwest holds constant.
- At current emissions levels, the average resident of the Southeast will experience 17 to 52 extremely hot days (days over 95˚F) by 2050 and 48 to 130 extremely hot days per year by 2100, up from a rate of eight extremely hot days per year for the past 30 years.
- The heat index, which measures the comfort of combined temperature and relative humidity, is expected to increase at a higher rate in the Southeast than in any other U.S. region.
Economic Impacts
- Heat increases are expected to decrease labor productivities in high-risk sectors like construction, mining, utilities, agriculture, and manufacturing by up to 3.2% by 2100.
- Summer heat, coupled with increased drought, is projected to reduce crop productivity in parts of the Southeast. In Georgia, heat stress is projected to cause a 15% decline in corn yields and a 20% decline in wheat yields through 2020.
Local Impacts and Recent Events
- During the summer of 2012, South Carolina reached an all-time state record high of 113 degrees.
- In 2011, Tallahassee, FL; Augusta, Athens, Columbus, and Savannah, GA; Charleston and Columbia, SC; and Cape Hatteras, NC all experienced their hottest summers on record.
- In 2007, a drought across the Southeast caused crop losses of $1.3 billion, with corn and peanuts primarily affected.
Sea Level Rise
Right Here, Right Now
- The coastline of Puerto Rico around Rincòn is being eroded at a rate of 3.3 feet per year due to current sea level rise.
- In Louisiana, 1,880 square miles of coastland have already been lost due to natural and man-made factors since the 1930s. From 1985 to 2010, 16.57 square miles of wetland were lost in Louisiana per year, a loss equivalent to one football field per hour. The loss of tidal wetlands puts Louisiana more at risk from the threats of storm surge and sea level rise.
Projected Trends
- The region’s sea level is projected to rise by 12-48 inches by 2100.
- If current emission trends hold, sea level in Norfolk, VA will likely rise between 1.1 and 1.7 feet by 2050, and by 2.5 to 4.4 feet by 2100. There is a 1-in-100 change that Norfolk, home to the nation’s largest naval base, could experience sea level rise up to 6.5 feet by the end of the century.
- Saltwater intrusion from rising sea level puts freshwater supplies at risk. In Florida, the Biscayne aquifer will likely experience significant impacts from saltwater intrusion by 2011. In Broward County, Florida, up to 50 wells will likely be affected with an increase in sea level of three to four feet, which puts the water supply of about 250,000 people at risk.
- 37,500 acres of Florida cropland will likely be lost if a 27-inch rise in sea level occurs.
Economic Impacts
- Major cities in southern Florida, built on porous limestone, could incur major costs even with modest sea level rise. Current projections estimate that $15 billion to $23 billion in property will likely be underwater in Florida by 2050, and between $53 billion and $208 billion will likely be underwater the end of the century. There is a 1-in-20 chance that more than $346 billion in property and a 1-in-100 chance that more than $681 billion in property will be underwater in Florida by 2100.
- Louisiana State Highway 1 is sinking as the sea level rises, resulting in more frequent and more severe flooding. A 90-day shutdown of this highly used road would cost the nation $7.8 billion, according to the Department of Homeland Security.
Local Impacts and Recent Events
- Over the last several years, salt water intrusion caused by sea level rise has forced the closure of water wells in several Florida cities (Hallandale Beach, Pompano Beach, Dania Beach, Latana, and Lake Worth.)
- North Carolina’s legislature restricted the use of climate change projections in coastal real estate assessment. The state now uses a forecast that looks 30 years out and predicts eight inches of sea level rise.
Extreme Precipitation and Storms
Right Here, Right Now
- In the Southeast, variability in precipitation has increased, with more exceptionally wet and dry summers seen since the mid-20th century. Compared to the historical record dating back to 1880, there has been a substantial increase in Category 4 and 5 hurricanes since the early 1980s. This increase is attributed to both natural variability and climate change.
- Daily and five-day rainfall intensities have increased in both the Southeast and Caribbean.
- Eight of the eleven Southeast states rank in the top 20 for lightning-related fatalities from 1959-2006
- Since 1958, the amount of heavy precipitation falling in single events in the Southeast has increased by 27%.
Projected Trends
- Precipitation patterns are hard to predict for the Southeast region. Most models project drier conditions in the northeast and wetter conditions in the southwest part of the region.
- An overall decrease of precipitation is likely in the Caribbean, with few areas of increased precipitation.
- Projections suggest that tropical storms will be fewer in number but more intense, with a greater number of Category 4 and 5 storms expected.
Economic Impacts:
- Coastal areas in Alabama, Mississippi, Louisiana, and Texas already face losses that average $14 billion annuallyfrom hurricanes, land subsidence, and sea level rise. If hurricane wind speed increases 3% as projected and sea level rises by just under 6 inches, losses for the 2030 timeframe could reach $23 billion. 50% of the increase in losses can be attributed to climate change.
- Over the past thirty years, the Southeast experienced more billion-dollar disasters than any other region in the United States.
Local Impacts and Recent Events
- In August 2011, 500,000 people were under mandatory evacuation orders in North Carolina and Virginia due to Hurricane Irene. Damages from the storm in North Carolina alone totaled $1.8 billion.
- In 2005, Hurricane Katrina displaced 200,000 people, stressing the social and physical infrastructures of the region. Evacuees experienced high levels of physical and mental trauma.
- In 2014, a rare ice storm impacted 70,000 acres of forest in Georgia, valued in excess of $65 million. This ice storm, the worst in over a decade, left over 300,000 people without power across the South, and resulted in at leastseven deaths.