An important new study, which you surely heard about on the evening news and read of in the paper, warns that the Greenland ice cap melt rate is changing dramatically. Or maybe you didn’t hear about it, because the study, bearing the salacious title “Decelerated Greenland Ice Sheet Melt Driven by Positive Summer North Atlantic Oscillation”, concluded that contrary to expectations and endless frantic warnings, the melt rate has been slowing down since 2013 rather than speeding up. The big headline you didn’t see because they didn’t run it says the decline in the Greenland ice cap is slowing down as part of, even more shocking, a natural cycle.
The authors discuss some of the ways natural forces affect Greenland ice, including solar variations, changing cloud cover and North Atlantic ocean circulation patterns, and explain how these things have lately been working together to tilt the balance away from melting towards ice cap formation on the big frozen island. Which is all very interesting and probably true. But we can’t help noticing that it’s only when the trend goes in an unexpected direction that scientists start to dig deep and try to figure out all the ways natural variability plays a role in our climate.
If the melt rate had been going up they’d likely have just chanted “climate change!”, a phrase here meaning “man-made climate change,” and left it at that. Certainly the press would have been happy to amplify such a message. But here’s the thing: If nature can explain a slow-down in melting, why can’t it also explain a speeding up? And the answer is simple. If you start suggesting that some of what we’ve been seeing warming-wise may just be natural variability you might lose your job, in the lab or the newsroom.
Still, nature sometimes forces scientists to look in the unexpected places to try and sort out all the genuinely complicated things going on in our climate. Now let’s bring such insights into the newspaper and the legislature as well.