Published: 2014-05-06 14:52:57
Updated: 2014-05-06 14:52:57
Posted May 6, 2014
By Nate Johnson
Raleigh, N.C. — The climate has changed, it is continuing to change and human activity is the leading contributor to that change in the last 50 years. So says the 2014 National Climate Assessment, a summary of climate change impacts in the United States authored by more than 300 experts.
Moreover, the report concludes that, even with aggressive reductions in carbon emissions, we will likely continue to see warming across the globe, changes in North Carolina’s weather patterns and climate-related impacts on our lives.
At the core, the report concludes the average temperature across the globe has increased more than 1.5°F since 1880, including a 0.5-1.5°F warming across North Carolina during that time. Locally, that’s leading to fewer nights below freezing, more days with highs above 95°F and a longer growing season (six days longer across the southeastern U.S.).
The warmer atmosphere is also contributing to other changes, including sea level rises. Globally, the report says, the average sea level has risen about 8 inches in the last century, and additional rises of 1 to 4 feet are projected. The Outer Banks and sound-side areas of North Carolina are highly susceptible to this rise, according to the report’s authors. In fact, the state Department of Transportation is raising the roadbed of U.S. Highway 64 in eastern North Carolina near the Albemarle and Pamlico sounds to protect it against rising sea levels.
Precipitation patterns are also shifting globally, with some areas getting wetter while others dry out. The desert Southwest, northern Rockies, Hawaii and parts of the Southeast have seen annual precipitation trending downward, with western and central North Carolina seeing drops of 5 to 15 percent of annual rainfall. As a result, the report asserts, availability of fresh water for drinking and other uses in much of North Carolina will also trend downward in the next 50 years, perhaps by 2.5 percent. The southeastern quarter of North Carolina may see water availability trend upward, however, as a result of higher precipitation trends.
The report also documents reductions in arctic sea ice, the mass of ice over Antarctica and in glacial ice content elsewhere, as well as changes in patterns of extreme weather events such as floods, droughts, snowstorms and hurricanes. It concludes with a wide range of response strategies, including mitigation (e.g., reducing carbon emissions) and adaptation techniques.