Thursday, 13 March 2014

Blowing Away The Warming Pause Mystery

Let's be honest. The 14 year pause in global warming has been been an embarrassment to climate modelers and a joy to climate change deniers. Until now. But now modellers at several research centres in Australia and the US have explained the pause as the effect of strong winds.

No-one who's been watching the UK news this year will be unaware of the persistent extreme weather - winds, rain, storms and floods - that has afflicted the UK. These extremes were predicted by climate models and will become more severe for decades to come whatever we now do.

Now these researchers noticed that the Pacific Trade Winds have been much stronger than forecast by the climate models. When they fed the actual wind speeds into a suitable model it showed that the winds made ocean currents stronger and that these currents drove more mixing between warm surface and cool deep waters. Result - lower surface temperatures and thus lower air temperatures. Thus the pause.

The study does not tell us whether the pause will continue since that depends on the degree to which future wind speeds exceed those in the climate change models.

There are lessons in humility here for all concerned!

Summary: New Scientist, 15/2/14, p 14.

Original paper: Nature Climate Change, 9 FEBRUARY 2014 | DOI: 10.1038/NCLIMATE2106