- 2015 global temperatures beat the previous high mark, set in 2014, by 0.23 degrees Fahrenheit (0.13 Celsius).
- 15 of the 16 warmest years on record have now occurred since 2001.
- Since the dawn of the industrial age in the late 19th century, Earth’s average surface temperature has risen about 1.8 degrees Fahrenheit (1.0 degree Celsius).
Earth’s surface temperatures were warmer in 2015 than any other year since modern record keeping began in 1880, NASA and the National Oceanic and Atmospheric Administration (NOAA) announced yesterday.
Not only that, but 2015 global temperatures beat the previous high mark, set in 2014, by 0.23 degrees Fahrenheit (0.13 Celsius). That may seem like a small amount of warming, but it is significant when you consider that global temperature averages usually only change a few hundredths of a degree from year to year.
Last year was not only the hottest on record, but it saw the second-largest jump between records ever. “Only once before, in 1998, has the new record been greater than the old record by this much,” NASA said in a statement.
“Climate change is the challenge of our generation, and NASA’s vital work on this important issue affects every person on Earth,” said NASA Administrator Charles Bolden. “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 scientists say that, based on the nature of the temperature data kept by the agency, they are 94 percent certain that 2015 was the hottest year yet. Researchers with the NOAA, which keeps its own data, performed their own analysis and concurred with NASA’s conclusions.
Since the dawn of the industrial age in the late 19th century, Earth’s average surface temperature has risen about 1.8 degrees Fahrenheit (1.0 degree Celsius), mostly due to increased emissions of carbon dioxide and other greenhouse gases into the atmosphere from human activities.
The use of fossil fuels for energy generation and deforestation for agriculture and a variety of other economic development activities are primary sources of manmade emissions.
A particularly strong El Niño event warmed the tropical waters of the Pacific Ocean for most of 2015, which certainly contributed to the overall 0.23-degree Fahrenheit increase.
But 2015’s record temperatures weren’t entirely El Niño’s fault and are entirely consistent with the long-term trend of global warming, according to Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies.
15 of the 16 warmest years on record have now occurred since 2001.
“2015 was remarkable even in the context of the ongoing El Niño,” Schmidt said in a statement. “Last year’s temperatures had an assist from El Niño, but it is the cumulative effect of the long-term trend that has resulted in the record warming that we are seeing.”
This visualization illustrates Earth’s long-term warming trend, showing temperature changes from 1880 to 2015 as a rolling five-year average. Orange colors represent temperatures that are warmer than the 1951-80 baseline average, and blues represent temperatures cooler than the baseline. Credit: GSFC Scientific Visualization Studio.
