June’s global land and sea temperature was a record high for the month, the 14th consecutive monthly record. But the rate of increase has slowed with El Niño ending. However, the expected La Niña is not developing as planned.
What Places Set Records In June And What Changed From May?
One of the best ways to judge the warmth of a month is to see how many records were set.
In the past few months, large swaths of the earth’s land and ocean areas set records for warmth.
In June, the record areas were smaller and more scattered. This is very likely a result of the change in the Pacific Ocean from El Niño conditions to neutral.
Some of the records were:
- The area of record temperatures in the tropical Pacific Ocean has shrunk to just the central Pacific south of the equator. This reflects the demise of El Niño.
- The large swath of record heat from the Indian Ocean to the western Pacific in May is now confined to Indonesia and northern Australia.
- Record temperatures persist in both the southern and northern Atlantic Ocean. The latter may affect the US hurricane season.
- Areas of record temperatures in Africa, Asia, and South America are smaller and more scattered than in May.
- The only area of record cold in June, as in May, was east of the Drake Passage between South America and Antarctica.
- The only land area that was below normal was in south central South America, but it was not record cold.
The First Half Of 2016
A single month can be anomalously warm or cold; longer term averages give a clearer idea of the trend. The first half of 2016 is off-the-charts warmer than any other such period. Unless the earth smashes into a planet-sized refrigerator, 2016’s global temperature will far surpass last year’s record.
January to June 2016 was warmest in all measured categories: land; sea; land and sea combined; northern hemisphere; southern hemisphere; whole globe. The notion that global warming leveled off after the anomalously warm El Niño years of 1997-98 has been left in the dustbin of bad ideas.
The question now is whether there will be a temporary reprieve from the massive increases in temperature of the last couple of years — enough to give the Paris Agreement (COP21) time to work. The evidence so far from the Pacific Ocean temperatures is that La Niña is not developing as previously forecast. Officially (according to NOAA), the odds are now at 60% for La Niña developing by fall, down from 75% last month. But Decoded Science, which had previously confidently predicted a robust La Niña on the basis of the historical record, has now become very much more cautious.
The failure of La Niña to develop quickly after a strong El Niño, coupled with persistent ocean anomalies in two oceans, raises troubling questions about the future of oceanic and atmospheric circulations.
Worldwide Sea Surface Temperatures (SST) And Atmospheric Circulation
El Niño, in its simplest form, is a sloshing of water back and forth across the Pacific Ocean. Trade winds blow water from east to west. Upwelling occurs on the coast of South America, keeping the water cool.
If a lull occurs in the trade winds, the water piled up near Asia can slosh eastward unleashing a Kelvin wave. Kelvin waves are confined to the equator by the spinning of the earth (the Coriolis force), and they warm the water by downwelling.
In a powerful El Niño such as the recent one, a succession of Kelvin waves keeps the water temperatures elevated across most of the Pacific.
Eventually the trade winds reassert themselves and cold water again upwells in the eastern Pacific and moves west. This year, the trade winds are only moderate, and La Niña conditions have been slow to develop.
A few years ago, a warm water pool developed in the Gulf of Alaska and was implicated in the California drought. Meteorologists (often at a a loss for useful words) named it ‘the blob.’ When the blob was replaced by a pool of cold water, probably associated with El Niño, Decoded Science (logically) named it ‘the anti-blob.’ The anti-blob is now dissipating, probably to be replaced by a new blob, which almost certainly means more drought for California.
Meanwhile, there has been a pool of anomalously cold water south of Iceland in the Atlantic. It seemed logical to call this the Atlantic anti-blob. The persistence of this feature is worrisome. Long-term changes in SST imply a change in ocean currents. Such changes could induce changes in the weather. Decoded Science has said it before, but it bears repeating: human civilization can deal with slow, uniform changes in temperature; but rapid, uneven changes in temperature or large changes in precipitation patterns would create severe problems.
2016 Will Be The Hottest Year; Will World Leaders Respond?
Human beings are famous for their ingenuity and ability to solve problems. But often that happens only after a crisis has arisen. So far, all crises, including the one posed by the existence of nuclear weapons, have been handled. It is not clear at what point global warming will be too far advanced to be handled. It will take a combined and concerted effort of all the countries of the world to keep the temperature from climbing above the two degree Celsius rise from pre-industrial levels that climatologists warn could result in catastrophic changes in the weather.
It is worth noting what one of the two major-party candidates for president of the United States, one of the world’s largest polluters, tweeted (later calling the tweet a joke):
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