Earth's Relentless Warming Just Hit a Terrible New Threshold
In an age of broken temperature records, this one is especially worrisome.
The number of climate records broken in the last few years is stunning. But here's a new measure of misery: Not only did we just experience the hottest April in 137 years of record keeping, but it was the 12th consecutive month to set a new record.
It's been relentless. May 2015 was the hottest May in records dating back to 1880. That was followed by the hottest June. Then came a record July, August, September, October, November, December, January, February, March—and, we learned from the National Oceanic and Atmospheric Administration on Wednesday—the hottest April. In an age of rising temperatures, monthly heat records have become all too common. Still, a string of 12 of them is without precedent.
Perhaps even more remarkable is the magnitude of the new records. The extremes of recent months are such that we're only four months into 2016 and already there's a greater than 99 percent likelihood that this year will be the hottest on record, according to Gavin Schmidt, who directs NASA's Goddard Institute for Space Studies.
The chart below shows earth's warming climate, measured by land and sea, dating back to 1880.
If NASA's Schmidt is right, 2016 will be the the third consecutive year to set a new global heat record—the first time that's ever happened. So far, 15 of the hottest 16 years ever measured have come in the 21st century.
Results from the world’s chief monitoring agencies vary slightly, and the National Aeronautics and Space Administration says April is only the seventh consecutive record-breaking month. But NASA, NOAA, and the Japan Meteorological Agency all agree that the extremes of 2016 are unrivaled in the modern climate record.
The NASA map below shows how heat was distributed across the globe last month. The most extreme heat swept the Arctic, where ice levels have been setting daily lows for this time of the year. Come summer, the ice cap at the top of the planet will likely be the smallest on record.
To be sure, some of this is the result of a monster El Niño weather pattern lingering in the Pacific Ocean. El Niño may finally be coming to an end, shifting this summer to a cooling La Niña by the time Arctic ice coverage reaches its nadir, according to NOAA's Climate Prediction Center. The agency gives a 75 percent chance of a La Niña pattern developing this year.
Beyond these cyclical changes, however, there seems no escaping the larger trend that we live on a planet that's warming rapidly. Coastal cities are flooding more regularly, wildfires are starting early, and the world is in the midst of the most prolonged die-off of the ocean's coral ever witnessed.
Perhaps most worrisome, if recent trends are any indication, is that it won't be long before this record-hot year looks cool, compared with what's to come.