Talk of climate change is very much about the potential for extreme weather events, and according to scientists at the recent American Geophysical Union meeting in San Francisco, hurricanes may be the least of our worries as time goes on. In fact, some scientists at that meeting predicted that global warming may not increase hurricane intensity much at all, but others warned that Europeans, at least, should get ready for future heat waves. UK scientists are predicting that virtually unprecedented heat events like that the one that occurred in 2003 will become commonplace in Europe within 20 to 30 years. Peter Stott of the UK’s Met Office Hadley Center for Climate Change reported on the findings of a paper that he and his MET colleagues published in the journal Nature Science Change on December 8. According to that paper, heat waves like the 2003 event that killed tens of thousands of people in Europe may soon become commonplace. The 2003 heat crisis was a one in five hundred year event, with no precedent going back at least to the year 1500. However, European summer temperature increases since 2003, as well as scientists’ climate models, indicate that such events are now occurring on average about twice per decade, a trend borne out by a heat event in Europe in 2012 that equaled the temperatures seen in 2003. Overall, summer temperature increases in Europe during the last 13 years have significantly exceeded natural variability and are following projections that show that such “500 year events” will occur every other year or so by the year 2040. The European heating trend now confirmed by observation was predicted by Stott, Stone, and Allen in a paper published in the journal Nature in 2004. That earlier paper attributed the 2003 heat wave to global warming, an eyebrow raising early instance of attributing a single extreme weather event to climate change by climat scientists. The 2004 Nature article also modeled an expected increase in such heat events. According to Stott et. al.’s recent paper, temperature trends have proven that models to be accurate, and the trend to more extreme events can be expected, says Stott.
The dramatic increase in European summer heat has occurred in the 21st century even while global mean temperatures are widely said to have experienced a “hiatus” during the same period. However, even the pause claimed by many observers and superficially indicated by atmospheric temperatures is far from the whole story. The atmosphere retains only one percent of the increased heat the earth is experiencing. Most of the heat is retained in the vast oceans, with the remainder stored in terrestrial features. Scientists also believe that natural and anthropogenic factors have partly masked atmospheric warming during the past decade, even while rapid arctic ice loss and extreme weather events demonstrate that climate change is indeed happening.
With MET Office scientists are predicting extreme heat waves in Europe to be commonplace by 2040, Stott warns that forestalling or preventing this worrisome trend demands heroic efforts to cut green house gases dramatically.