Monday, November 30, 2015

Bigger Fish to Fry

In the next few weeks, as the climate hype in Paris builds to the boiling point, there are several critical points to keep in mind. In Saturday’s WSJ, Matt Ridley and Benny Peiser helpfully presented Your Complete Guide to the Climate Debate:

It cannot be what is happening to world temperatures, because they have gone up only very slowly, less than half as fast as the scientific consensus predicted in 1990 when the global-warming scare began in earnest. Even with this year’s El NiƱo-boosted warmth threatening to break records, the world is barely half a degree Celsius (0.9 degrees Fahrenheit) warmer than it was about 35 years ago. Also, it is increasingly clear that the planet was significantly warmer than today several times during the past 10,000 years.

Is the planet getting warmer? Yes, but not nearly as fast as climate models had predicted.

Is the warmer caused at least in some part by human activity? Probably, but just how much is anthropogenic and how much is natural is difficult if not impossible to pinpoint.

But the bigger question is whether the warming that has occurred and the future warming that is predicted to occur will be disastrous for mankind and the planet?

Nor can it be the consequences of this recent slight temperature increase that worries world leaders. On a global scale, as scientists keep confirming, there has been no increase in frequency or intensity of storms, floods or droughts, while deaths attributed to such natural disasters have never been fewer, thanks to modern technology and infrastructure. Arctic sea ice has recently melted more in summer than it used to in the 1980s, but Antarctic sea ice has increased, and Antarctica is gaining land-based ice, according to a new study by NASA scientists published in the Journal of Glaciology. Sea level continues its centuries-long slow rise—about a foot a century—with no sign of recent acceleration.

So while the Syrian civil war and the ensuing rise of ISIS may be at least partially due to drought in the region there is no evidence that said drought was the result of increased carbon emissions.

Okay, so the impact of global warming hasn’t hit us yet. But what about the future?

Perhaps it is the predictions that worry the world leaders. Here, we are often told by journalists that the science is “settled” and there is no debate. But scientists disagree: They say there is great uncertainty, and they reflected this uncertainty in their fifth and latest assessment for the United Nations Intergovernmental Panel on Climate Change (IPCC). It projects that temperatures are likely to be anything from 1.5 to 4.5 degrees Celsius (2.7 to 8.1 degrees Fahrenheit) warmer by the latter part of the century—that is, anything from mildly beneficial to significantly harmful.

As for the impact of that future warming, a new study by a leading climate economist, Richard Tol of the University of Sussex, concludes that warming may well bring gains, because carbon dioxide causes crops and wild ecosystems to grow greener and more drought-resistant. In the long run, the negatives may outweigh these benefits, says Mr. Tol, but “the impact of climate change does not significantly deviate from zero until 3.5°C warming.”

Mr. Tol’s study summarizes the effect we are to expect during this century: “The welfare change caused by climate change is equivalent to the welfare change caused by an income change of a few percent. That is, a century of climate change is about as good/bad for welfare as a year of economic growth. Statements that climate change is the biggest problem of humankind are unfounded: We can readily think of bigger problems.” No justification for prioritizing climate change over terrorism there.

And that is the most important point of all. We should be talking about climate change, what the realistic impacts will likely be, and what can be done to mitigate its negative consequences without placing undue burdens on the global economy and limiting less developed countries from growing their way out of poverty. But we should not pretend that it is the greatest threat facing us today and that it should be the primary focus of world leaders as the gathering in Paris would have you presume. There are a lot of problems in the world that require our attention. Climate change is not at the top of that list.

UPDATE--For more of the pragmatic perspective on climate change, check out this Prager U video featuring Bjorn Lomborg: