NOAA released its global analysis of land and sea temperatures for May 2016 on June 16. For a change, it wasn’t the hottest ever by every metric, although measured over the entire globe it was indeed the warmest May at 15.67°C (0.02°C higher than the previous record set last year).
The decline was in the departure from average, which was less than one degree Celsius for the first time in six months.
May 2016 was 0.87°C above the May average. This is an alarming increase in a world that is struggling to find a way to restrict global warming to the magic number of 2°C, at which point many scientists believe catastrophic changes in the weather are inevitable.
Still, this decline represents a ray of hope trying to pierce the gathering clouds of climate change. Let’s look at the particulars.
New Records Were Set — But Not Everywhere
For five consecutive months, new temperature records have been set in all nine categories of land and sea temperature by full globe and hemisphere. In May, there were only four number ones: Global land and sea; global sea; southern hemisphere land and sea; southern hemisphere sea. In the northern hemisphere, land and sea was second warmest, sea was second warmest, and land was third warmest. Observations go back to 1880, so the comparison comprises 137 years.
The map of temperature percentiles gives a better picture than the temperatures themselves. The temperature tends to vary much more over land than sea, more over dry areas than humid ones, and more in mid-latitudes than the tropics. The percentile map shows that a large portion of the earth was warmer than it has ever been in May.
- Even with El Niño fading into neutral territory, the central tropical Pacific was still record warm.
- Most of the Indian Ocean was record warm.
- The central sub-tropical North Atlantic was record warm. The records extended westward into the northwest Caribbean.
- A patch of the South Atlantic near Brazil was record warm.
- Eastern Australia and the waters to the east were record warm.
- The warmth in the tropical Indian Ocean extended eastward through Indonesia and adjacent waters.
- The Arabian peninsula was record warm.
- Parts of northern South America were record warm.
- One tiny spot in the south Atlantic near Antarctica was record cold.
- Though they set no records, the ‘anti-blobs’ in the North Atlantic and North Pacific Oceans persisted with much below normal sea surface temperatures.
2016 On Course To Shatter All Temperature Records
Temperatures averaged over a longer period of time generally give a clearer view of the trend. The first five months of 2016 are hottest since 1880 in every category measured by NOAA: land, sea, northern and southern hemisphere, and all combinations. The year is running so far ahead of any other comparable period that many scientists have shortened the time frame for global warming to reach dangerous levels.
A Realistic Look Ahead
Most climatologists believe the recent surge in global temperatures was exacerbated by El Niño. May is an indication that temperatures may now return to a less worrisome trajectory. Decoded Science has repeatedly pointed out that statistics are as slippery as eels. But we think that a comparison between the El Niño of 1997-98 and the one now ending gives a valid approximation for the actual rise in temperature. And using the period January through May should give a better approximation to the change than just using a singe month.
The global land and sea temperature has risen by 0.33°C from Jan-May 1998 to the same period in 2016. This is a rate of about 1.8°C per century. Considering that the global temperature has already risen nearly a degree, we only have about 60 years to find a way to cap the total temperature rise at 2°C.
This might seem like plenty of time, but it is not. Even if emissions were cut to zero today, the atmosphere would continue to warm as it adjusts to the increased greenhouse gases emitted over the last century. Estimates center around an additional increase of 0.6°C. That doesn’t leave much room to maneuver. And far from cutting emissions to zero, many countries of the world are increasing their emissions. All the signatories to the recent Paris agreement are formulating plans for cutting emissions that vary from promising to vague.
Climate: A Final Word
The climate bears an analogy to international finance. When a commodity undergoes a slow, steady change in price, the world reacts with minimal disruption. But if the price changes rapidly, wild fluctuations ensue across a spectrum of economic activity.
If the temperature across the globe were to rise a uniform 2°C over a long period of time, the disruption would be minimal. But it is already apparent that global warming will not be uniform; temperatures in the Arctic are rising three times as fast as anywhere else.
Climatologists are particularly worried about changes in ocean currents such as the Gulf Stream, which keeps Europe remarkably warm considering its latitude. Decoded Science has noted the anti-blobs, particularly the very persistent one in the Atlantic. Could that be the tip of an ocean-current-change iceberg?