A new report warns that climate change driven by human activity already 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 frightening 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’s designed to provide a thorough overview of the status of climate science and climate change impacts.
It came the same week that the National Oceanic and Atmospheric Administration said U.S. temperatures in 2012 were the highest since record-keeping began in 1895. But the draft assessment warns that human-induced climate change "means much more than just hotter weather."