Will Climate Get Even Weirder?
Even though we just lived through the warmest calendar year, the warmest twelve month period, the warmest January and probably the warmest February on record, the most entrenched deniers cite the arctic conditions this winter in the Eastern US as proof that there is no, “global warming.” Even so, easily observable weather events of the last few years – superstorms, torrential rains, mudslides, derechos, heat waves, droughts – are slowly beginning to turn the tide of public opinion on Climate Change, or perhaps Global Weirding. But according to a paper in Science Magazine, we’re in for a lot worse very soon. I don’t have a subscription to Science Magazine, and the abstract is just abstract, but here is a slightly edited version of the Editor’s summary:
Atlantic and Pacific multidecadal oscillations and Northern Hemisphere temperatures
Byron A. Steinman, Michael E. Mann, Sonya K. Miller
Which recent climate changes have been forced by greenhouse gas emissions, and which have been natural fluctuations of the climate system? Steinman et al. combined observational data and a large collection of climate models to assess the Northern Hemisphere climate over the past 150 years … At various points in time, the Pacific Multidecadal Oscillation (PMO) and the Atlantic Multidecadal Oscillation (AMO) have played particularly large roles in producing temperature trends. Their effects have combined to cause the apparent pause in warming at the beginning of the 21st century, known as the warming “hiatus.” This pause is projected to end in the near future as temperatures resume their upward climb.
On Science Blogs, Greg Laden discusses the article and shows some helpful charts. The paper notes that Pacific Ocean temperatures have been low, but are due to swing back up, and since the Pacific is so large, it will drive the whole system temperature up. Even with the Pacific trending low we have seen record warming and bizarre weather. What happens next?
Study author Michael Mann told me, “The PMO appears to be very close to a turning point, based on the historical pattern. So we don’t expect it to continue to plunge downward. We expect a turning point soon.” In his summary of the work in Real Climate, Mann notes that “the most worrying implication of our study [is] that the “false pause” may simply have been a cause for false complacency, when it comes to averting dangerous climate change.”
There won’t be any averting. There will be a great deal of death, loss, hardship and regret, followed by half-measures and finger-pointing.
Update 20150301: Scientific American, The Pause in Global Warming Is Finally Explained