NASA and NOAA announced today that 2015 was the hottest year on record. It quickly trounced the previous hottest year on record, 2014, by a margin of 0.23 degrees Fahrenheit, which doesn't sound, on paper, like much. But it marks the biggest uptick on a year-to-year scale of warming temperatures around the planet since 1998.
"Today's announcement not only underscores how critical NASA's Earth observation program is, it is a key data point that should make policy makers stand up and take notice - now is the time to act on climate," NASA administrator Charles Bolden said in a press release.
The latest uptick marks an overall global temperature difference of 1.8 degrees Fahrenheit across the 20th century and into the 21st. Official temperature records stretch back to 1880. Much of the warming was seen in the last 35 years, with a worldwide uptick in industrialization and the continued reliance of the United States, China, and other countries on fossil fuels for electricity.
But 2015 had another contributor to warming, alongside anthropogenic climate change. The El Niño storm system played a role as well. The storm system, which occurs every seven years, has a large effect on global temperatures. But Gavin Schmidt of the Goddard Institute for Space Studies said in the same release that the changes were remarkable, even with El Niño factored in.
Without major action on climate change worldwide, the trend will continue in the coming decades, meaning more droughts in California and the Heartlands, more megastorms, more flooding, and all around more ecological disasters. It's going to be a bumpy ride.