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Although many prominent climate scientists will not countenance its existence, the so-called “hiatus” is the most talked about and researched topic in climate science. It is a significant mystery for which there have been many explanations proposed with a growing suspicion that perhaps the oceans are involved in some way.

Writing in the journal Nature recently, Gerald Meehl, of the U.S. National Center for Atmospheric Research, said the many adjustments of the surface temperature data sets — adjustments that invariably eliminate the hiatus — have not been as definitive as some suggest. He says the claims of “no hiatus” rest on questionable interpretations of forced climate change due to greenhouse gasses and their relationship with inter-decadal and decadal natural climate variability. The hiatus is clear, he says, and not an artifact of the data.

This means that in the past 20 years or so the anthropogenic warming signal is being obscured by decadal climatic variability and it could be several decades before man’s influence emerged and exceeded nature. As the journal Nature Climate Change said recently, “Longer-term externally forced trends in global mean surface temperatures are embedded in the background noise of internally generated multidecadal variability.” Pruitt’s comments recognize that.

Some are adamant that the “hiatus” does not and never has existed, and will never change their minds. But the evidence is irrefutable. As a large number of influential climate scientists have just said in the journal Nature Geoscience, since the turn of the century there has been a substantial slowdown in warming that computer climate models did not predict or can explain. In fact, such models predict a warming twice that observed. This confirms what Pruitt has said. If anyone tells you that the science is settled tell them that this is just the start of climate science and not its end.

Some scientists and campaigners may find it inconvenient and uncomfortable but the EPA’s Pruitt has a point backed-up by science.

David Whitehouse is a writer and broadcaster, and science editor of the Global Warming Policy Foundation.