For years, scientists have kept an anxious eye on global temperatures that keep going up…and up…and up. Now, the numbers for 2016 are in, reports The Washington Post’s Chris Mooney. And they’re sobering. Last year was the hottest ever recorded—the third year in a row that the hottest-ever temperature record has been broken.
That’s the consensus of both NASA and the National Oceanic and Atmospheric Administration, which both issued data declaring 2016 the warmest year since either institution started keeping records. It was 0.07 degrees Fahrenheit warmer than 2015, edging out the previous year by a small but recognizable amount. As Mooney reports, NASA expressed more than 95 percent confidence in its record, while NOAA expressed a 62 percent degree of certainty in the accuracy of their conclusion.
The data was presented in two reports that came out concurrently. In NOAA’s annual State of the Climate Report, the agency noted that 2016 clocked in at the warmest year since modern record keeping began in 1880 and that the combined land and ocean average surface temperature in December was the third highest on record.
NASA’s report agreed with NOAA’s assessment. The agency noted that most of the warming trend took place within the last 35 years, and all but one of the warmest years happened since 2000. In addition, notes NASA, 2016 smashed records for warmest month on record, with two thirds of the months of the year the warmest ever recorded.
El Niño, the weather phenomenon that warms waters in the Eastern Pacific Ocean and fuels atmospheric warming in turn, is partially responsible for the warming trend. In a release, NASA officials note that 0.2 degrees Fahrenheit of the global temperature anomaly—the amount 2016 differed from the annual mean temperature from 1980 to 2015—can be attributed to El Niño. But the 2016 mean temperature was a full 1.78 degrees Fahrenheit higher than the mean. The rest of the deviation can likely be contributed to manmade causes.
In an animation released by NOAA along with the report, those manmade causes are all too evident. The image shows a dramatic rise in global annual temperatures in recent years—rises fueled by the greenhouse gases emitted by everything from large-scale farming and transportation to electricity production. As the United States Environmental Protection Agency notes, human activity is responsible for nearly all of the greenhouse gas increases in the last 150 years, and people’s reliance on fossil fuels is the primary driver of those greenhouse gases.
“Climate experts have long known that global warming due to increasing greenhouse gases won’t necessarily mean that each year on Earth will be warmer than the last,” writes NOAA. That’s because natural variability in short-term climate patterns can influence the temperatures of land and sea. As a result, NOAA doesn’t expect 2017 to be another record-breaking year.
All that record breaking is a double-edged sword when it comes to convincing policymakers to address the threat of ongoing climate change. Despite evidence that increasing temperatures fuel everything from severe weather to more fires, it can be hard to drive action without data that shows just how severe the situation has become. (On its website, NOAA includes a list of global occurrences like typhoons and ice melt that illustrate just how high temperatures impact things on Earth.) But too many records could fuel complacency and convince the public that “highest ever” is the new normal, a mindset that could further endanger Earth and fuel the myth that it’s too late to turn back. For now, perhaps it’s best to focus on the numbers themselves—numbers that show that Earth is in uncharted, unsettling temperature territory.