Separate analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA) reveal that the global average temperature broke the previous record – set in 2014 – with a rise of 0.13 degrees Celsius (0.23 degrees Fahrenheit).
Advertisement
Past year was far and away the hottest the planet has seen since at least 1880 when record-keeping began – and 2016 is likely to be even warmer, federal scientists said Wednesday. 2015’s average temperatures were about a third of a degree Fahrenheit higher than those recorded in 2014, which is the widest margin by which a temperature increase has ever been recorded.
The latest uptick marks an overall global temperature difference of 1.8 degrees Fahrenheit across the 20th century and into the 21st. Fifteen of the 16 hottest years on record occurred between 2001 and 2015, but 2015 was still a standout. NASA Goddard Institute for Space Studies (GISS) Director Gavin Schmidt expressed that El Niño had a significant effect over 2015’s warm temperature, yet the increasing trend and the record-breaking heat were products of a long-term cumulative effect.
The time-lapse video uses orange colours to represent temperatures warmer than the baseline average between 1951-1980, and blues to represent temperatures cooler than the baseline. “Only once before, in 1998, has the new record been greater than the old record by this much”.
For the continental United States, 2015 was the second warmest ever with a December that was the hottest and wettest on record. In previous years when we saw records being set, the gap remained significantly smaller than what we witnessed this time around.
The last time carbon dioxide reached 400 ppm was roughly 4.5 million of years ago, according to a 2009 report in the journal Nature Geoscience.
“This record year really is just emphasizing the fact that there is a very, very strong long-term trend in temperature that we have associated very strongly with the human emissions of greenhouse gases”, Schmidt said.
But Schmidt says El Nino is not the cause of the record warm year.
Advertisement
Non-scientists who reject mainstream climate science often criticize NOAA for adjustments to past temperature records to reconcile the measurement devices with modern techniques, but even without any adjustments NOAA data shows 2015 as the hottest year on record, Karl said.
