PUTTING CLIMATE CHANGE CLAIMS TO THE TEST

by John Christy, June 18, 2019 in GWPF


This is a full transcript of a talk given by Dr John Christy to the GWPF on Wednesday 8th May.

When I grew up in the world of science, science was understood as a method of finding information. You would make a claim or a hypothesis, and then test that claim against independent data. If it failed, you rejected your claim and you went back and started over again. What I’ve found today is that if someone makes a claim about the climate, and someone like me falsifies that claim, rather than rejecting it, that person tends to just yell louder that their claim is right. They don’t look at what the contrary information might say.

OK, so what are we talking about? We’re talking about how the climate responds to the emission of additional greenhouse gases caused by our combustion of fossil fuels. In terms of scale, and this is important, we want to know what the impact is on the climate, of an extra half a unit of forcing amongst total forcings that sum to over 100 units. So we’re trying to figure out what that signal is of an extra 0.5 of a unit.

Here is the most complicated chart I have tonight, and I hope it makes sense: