A new federal report warns that climate change driven by human activity is affecting the American people and economy, with more frequent and intense heat waves, heavy downpours and, in some places, floods and droughts.
A draft version of the National Climate Assessment that was released Friday warns that as the Earth continues to warm because of increasing levels of greenhouse gases in the atmosphere, the health and livelihoods of many Americans and the ecosystems that sustain the country face some impacts. Sea levels are rising, scientists warn, oceans are becoming more acidic, and glaciers and arctic sea ice are melting.
The National Climate Assessment, which is required under the Global Change Research Act of 1990, is presented to the president and Congress every four years. It is to provide a thorough overview of the status of climate science and climate change impacts.
The report came the same week that the National Oceanic and Atmospheric Administration said U.S. temperatures in 2012 were the highest since recordkeeping began in 1895. But the draft assessment warns that human-induced climate change "means much more than just hotter weather."
The report references increases in ocean and freshwater temperatures, frost-free days and heavy downpours. There's also more extreme weather, including more frequent and intense winter storms along the West Coast and the coast of New England. Such storms include Sandy in late October, which while not a particularly intense hurricane, exposed the sorts of problems that communities may face as sea levels rise.
"This draft report sends a warning to all of us: We must act in a comprehensive fashion to reduce carbon pollution or expose our people and communities to continuing devastation from extreme weather events and their aftermath," Sen. Barbara Boxer, D-Calif., who heads the Senate Environment and Public Works Committee, said in a statement.
The National Climate Assessment is coordinated by the U.S. Global Change Research Program, which is made up of 13 federal agencies. It's produced by a 60-member federal committee made up of notable scientists, business leaders and other experts. The final assessment will be released early in 2014.