Seeing the Forest for the Trees

Its hard to quote only relevant bits, as this is already a summery of their “most important conclusions” (their words). I think its worth a read, this is not a scientific paper but a mailing meant to communicate scientific information to the public. I’ve omitted a lot of the evidence they present because I think you should look at the mailing for that, anything I quote would be inadequate.

The case with climate sensitivity 3°C for doubled CO2 and IPCC aerosol forcing does not readily achieve the recent 1.6°C global temperature level nor produce a global temperature jump of 0.4°C in the past few years.

Climate change depends on climate sensitivity and the strength of the forcing that drives change. Of the main sources of information – paleoclimate, modern observations, and GCMs – the first two are least ambiguous, but all three are consistent with climate sensitivity 4.5°C ± 1°C (2σ, 95% confidence) for doubled CO2, which excludes IPCC’s best estimate of climate sensitivity (3°C for doubled CO2). IPCC also underestimates the strength of the aerosol climate forcing.

The Secretary General of the United Nations asserts that the goal of keeping global warming under 1.5°C is still reachable if nations increase their ambitions for future emission reductions. In reality, the 1.5°C goal has long been deader than a doornail.

In our present communication, we criticize IPCC’s science analysis…

When we presented our most recent paper, responses in the media by other scientists consisted of ad hominem attacks on the first author, e.g., “Hansen exaggerates,” “Hansen makes lots of mistakes,” “Hansen is not collegial,” and comments that our analysis was “too simple” and our conclusions were “outside the mainstream.” None of the comments addressed the climate science in our paper, which we have summarized here. Yet these few articles in the media, appearing on the day that our paper came out, were sufficient to shut down public discussion of our paper.

Fireflies. Lastly, I note that Lightning bugs are making a comeback this summer. We will miss the displays we saw on our farm in Bucks County, but I will see if there are any in Riverside Park. Longterm, insects will depend on whether insecticides and herbicides are controlled.