The Winds of Warming

Contributed by
Feb 11, 2014
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I’ve written many times about the so-called pause in global warming. The claim is that the rise in temperatures on Earth has flattened since 1998, with some people even claiming the Earth has cooled somewhat.

There are many ways to look at this, all of which show that these claims are wrong.

One is that 1998 was an unusually warm year, so by starting there you’re bound to see temperatures slowing their rise a bit. That’s called cherry-picking and is a favorite technique among those who deny global warming is occurring. It’s a no-no.

Another is that what’s being used are ground and sea-surface temperatures, which aren’t a very good way to measure global warming. The lion’s share of the extra heat from warming is being stored in deeper ocean water. We can measure that, and it’s seen.

Another is that we see fluctuations over a period of a few years in the historical temperature record all the time. The Pacific Ocean affects surface temperatures, and that goes through multiyear cycles termed El Niño and La Niña. This can make it look like warming is slowing or speeding up, so you have to be careful and remove that signal from the data. You have to look at trends that last for many years, not just a few.

We do still see a rise in temperatures across the Earth, but interestingly it’s not quite as rapid a rise as the models predict. Why would that be?

A recent study showed that it is at least partly due to a lack of good coverage in the Arctic. Far northern latitudes are much more affected by global warming than midlatitudes, and if you leave those temperatures out, then you don’t see as fast a rise as you should. That study shows that when you account for this, warming rates in the surface temperatures go up, closer to what the models predict.

And now we have yet another study that shows that winds are playing a role. Basically, unusually strong winds in the Pacific over the past decade or so have helped drive warm water down deeper into the ocean and dredge up cooler water from below. This has in turn created cooler surface temperatures than expected. It’s not clear if these winds have arisen naturally, as part of the multiyear Pacific cycle, or if they are in turn due to climate change itself.

Either way, no matter how you slice it, this “pause” is nothing of the sort. At best, the warming is continuing apace, but just not affecting surface temperatures as much. Once things return to normal—whatever that is these days— we can expect surface temperatures to start rising at the same rate once again.

This exemplifies the science of climatology, in my mind. No matter how you look at it, if you’re honest then you’ll see that this “pause” isn’t real. At best you can say that the models predict we should be getting hotter faster, though it’s a small effect. But even then, real climatologists have pounced on this, prying the idea apart, poking it, prodding it, and seeing what they can find. And they did in fact see that we need better Arctic coverage and a better understanding of wind patterns over the ocean.

Real science doesn’t deny an effect. It investigates it honestly and tries to pry out the root causes. And that’s precisely what’s happening.

The problem is quite different for people who want to communicate the reality of climate change. For one, these changes are subtle and slow, making it hard to convey urgency. The other is that the changes can be somewhat complex, making it easy to muddy the waters, which is what deniers do.

But the deniers are running out of rope. As more real science gets done, fake skepticism sees its precarious path getting narrower, and soon it will be gone. Sadly, that just means they’ll get louder, write more ridiculous op-eds, and make even more outrageous claims (though they’ll have to reach pretty far to beat the assininery of “carbon dioxide is plant food”). And during all that time the world will be heating up. We’ll be getting more extreme weather, more droughts in some places, more floods in others, and real action will be delayed.

And that is a price we’ll all pay.