Scientists have been debating the veracity of global warming for a long time. In 2010, the National Oceanic and Atmospheric Administration said that there was no doubt that global warming was real in light of the overwhelming evidence.
Scientists are urging the United States and other nations to cut carbon dioxide emission levels now, before even more damage can be done. The U.N. is in the process of drafting a report urging nations to stop wasting time with politics and start cutting greenhouse gas emissions.
The U.N. report's draft shows that although large shifts in climate change are unavoidable at this point, we still have a chance to prevent damaging the climate even more by beginning to cut greenhouse gas emissions now rather than waiting until it's too late.
Most scientists agree that climate change is a real, human-created phenomenon, but some evidence seems to contradict a steep upward tick in global temperature. A December 2013 study published in the journal Nature Climate Change shows that Earth's average surface temperature has been fairly consistent since 2001, although greenhouse gases like methane and carbon dioxide have been consistently increasing. One theory they proposed was that strange winds were causing a hiatus in global warming, but that temperatures would continue to rise once the hiatus ended. A recent study published in Science says that this stability in temperature is due to the currents in the Atlantic trapping heat and pushing it down, further from the atmosphere.
Despite this possible warming hiatus, other scientists argue that even though average surface temperatures have not been rising, there has not been a hiatus - the Earth is just warming in different ways.
A new report from the Intergovernmental Panel on Climate Change (IPCC) suggests that instead of focusing on the surface of the Earth, we should be looking at the overall picture. Ice sheets, for example, have been getting warmer in the past few years, and a study published earlier this month suggests that humans are to blame for the melting glaciers.
The team, led by Dr. Sonia Seneviratne, also found that although the average land temperature had only risen slightly, there was a large increase in areas on land with extreme heat (more than 50 days in a row of extreme heat). The increase can be seen on this graph.
The U.N. says that it's time to put aside our doubt and start making immediate change. "Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems," a draft of the U.N.'s report said.
