Friday, the world was treated to the latest, greatest report on global warming from the United Nations’ Intergovernmental Panel on Climate Change (IPCC) in the form of its Fifth Assessment Report. It is an embarrassment of internal inconsistency, entirely self-serving, and is beyond misleading.
That’s because the IPCC is more intent on maintaining the crumbling “consensus” on global warming than on following climate science to its logical conclusion; a conclusion that increasingly suggests that human greenhouse gas emissions are less important in driving climate change than commonly held.
That’s right, the latest climate science (some 10 studies published in just the past 3 years) indicates that the earth’s climate sensitivity—that is, how much the global average surface temperature will rise as a result of greenhouse gases emitted from human activities—is some 33 percent less than scientists thought at the time of the last IPCC Assessment, published in 2007.
A little climate 101: climate sensitivity is one of the key parameters for understanding the future impacts from climate change.
Virtually all elements of climate are related in some way to changes in the earth’s average temperature.
The less the earth warms up, the fewer the resulting impacts, and the lower the urgency to try to do something to alleviate them.
Meaning, initiatives like President Obama’s Climate Action Plan—the motivation for such things as the EPA’s just-announced effective moratorium on future coal-fired power plants—would be even more unnecessary and ineffective than they are already.
The IPCC is not altogether blind to the new scientific findings indicating a lower climate sensitivity, but it barely pays them lip-service in its new report.
The meat of the new IPCC report – and the part that politicians predominantly look to for new legislation – is its projections of future climate change.
The problem is that the climate models the IPCC relies upon to produce these projections have a climate sensitivity that averages some 50 percent higher than what the latest science suggests.
This means that the IPCC’s projections of future climate change and the resulting impacts are nearly twice as large as they likely should be. In other words, the models don’t work.
The IPCC can’t very well admit to the fact that observations say one thing, but the climate models say another. If they did, they would have to throw out virtually the whole report.
But just because the IPCC doesn’t admit to it, doesn’t mean that the rest of the world doesn’t know it to be true.
It is increasingly obvious that the earth’s average temperature over the past several decades has refused to warm up at the rate foretold by these climate models.
In fact, there has been no clear large-scale surface warming for more than 16 years now, and a new paper published earlier this month in the prestigious journal Nature Climate Change affirms the climate models inability to correctly simulate these observations.
So we have a situation in which the latest science on two key issues: how much the earth will warm as a result of human greenhouse gas emissions, and how well climate models perform in projecting the warming, is largely not incorporated into the new IPCC report.
In this manner, the IPCC misleads policymakers around the world.
The IPCC’s exaggerated projections are the root of fears of coming climate disaster (sinking cities, storm-ravaged coastlines, widespread famine, etc.)—fears that result in calls to limit our use of fossil fuels used to produce the energy that supports human society and feeds innovation.
If mankind is to contemplate such a major undertaking with the attached risk that it drives the human condition backward, shouldn’t the basis be something other than an IPCC report that is obsolete and counterfactual on the day of its release?
Instead of laboring to try to uphold a consensus that was tenuous from the outset, and which is now outdated, the IPCC should be striving to produce a summary of the contemporary bank of scientific knowledge. Only with that type of information can responsible decisions pertaining to the development of world’s energy sources be made.
Paul C. "Chip" Knappenberger is the Assistant Director of the Center for the Study of Science at the Cato Institute.