The biggest contribution scientists can make to #scicomm related to the newly released IPCC Sixth Assessment report, is to stop talking about the multi-model mean. We’ve discussed the issues in the CMIP6 multi-model ensemble many times over the last couple of years – for instance here and here. There are two slightly contradictory features of […]
Tag: Paleoclimate
A Tale of Two Hockey Sticks
Two decades ago, the so-called “Hockey Stick” curve, published in 1999 by me and my co-authors (Mann, Bradley and Hughes, 1999), was featured in the all-important “Summary for Policy Makers” (SPM) of the 2001 IPCC Third Assessment report. The curve, which depicted temperature variations over the past 1000 years estimated from “proxy data such as […]
The IPCC Sixth Assessment Report
Climate scientists are inordinately excited by the release of a new IPCC report (truth be told, that’s a bit odd – It’s a bit like bringing your end-of-(seven)-year project home and waiting anxiously to see how well it will be received). So, in an uncharacteristically enthusiastic burst of effort, we have a whole suite of […]
Laschamps-ing at the bit
A placeholder to provide some space to discuss the paper last week (Cooper et al, 2021) on the putative climate consequences of the Laschamps Geomagnetic Excursion, some 42,000 yrs ago. There was some rather breathless reporting on this paper, but there were also a lot of sceptical voices – not of the main new result […]
Climate Sensitivity: A new assessment
Not small enough to ignore, nor big enough to despair. There is a new review paper on climate sensitivity published today (Sherwood et al., 2020 (preprint) that is the most thorough and coherent picture of what we can infer about the sensitivity of climate to increasing CO2. The paper is exhaustive (and exhausting – coming […]
10 years on
I woke up on Tuesday, 17 Nov 2009 completely unaware of what was about to unfold. I tried to log in to RealClimate, but for some reason my login did not work. Neither did the admin login. I logged in to the back-end via ssh, only to be inexplicably logged out again. I did it […]
?First successful model simulation of the past 3 million years of climate change
Guest post by Matteo Willeit, Potsdam Institute for Climate Impact Research A new study published in Science Advances shows that the main features of natural climate variability over the last 3 million years can be reproduced with an efficient model of the Earth system. The Quaternary is the most recent geological Period, covering the past […]