You are here: Home / Climate Science / Climate modelling / Cosmic rays and clouds: Potential mechanisms Guest Commentary by Jeffrey Pierce (Dalhousie U.) I’ve written this post to help readers understand potential physical mechanisms behind cosmic-ray/cloud connections. But first I briefly want to explain my motivation. Prior to the publication of the aerosol nucleation results from the CLOUD expe

Guest commentary from Dirk Notz, MPI Hamburg “Well, it’s not really good timing to write about global warming when the summer feels cold and rainy”, a journalist told me last week. Hence, at least here in Germany, there hasn’t been much reporting about the recent evolution of Arctic sea ice – despite the fact that Arctic sea ice extent in July, for example, was the lowest ever recorded for that mo

Hope the next IPCC report has a better section on the retreat of sea ice. It has already retreated faster than all models under all scenarios; obvious bias in the models. Also, the IPCC chart comparing models was a display of the average extent during the months of July, August and September. The implication being that there can’t be any sea ice during those months before the arctic can be said to

You are here: Home / Climate Science / Aerosols / The CERN/CLOUD results are surprisingly interesting… The long-awaited first paper from the CERN/CLOUD project has just been published in Nature. The paper, by Kirkby et al, describes changes in aerosol nucleation as a function of increasing sulphates, ammonia and ionisation in the CERN-based ‘CLOUD’ chamber. Perhaps surprisingly, the key innovation

New results from the University of Aarhus in Denmark and the Danish National Space Institute allegedly show that particles from space create cloud cover, according to a recent press release. And the Physics World magazine (May, 2011) report that the researchers say this is the best experimental evidence yet that the Sun influences the climate by altering the intensity of the cosmic-ray flux reachi

Perhaps a way to connect with Joe Sixpack? Tagline: If we can pay as much attention to the Earth as we do to our beer, we probably wouldn’t need to worry about global warming. Design by S. Han, loosely based on IPCC (2007), courtesy of the “Artist as Citizen” initiative. (Full size pdf version)

You are here: Home / Communicating Climate / Coldest Winter in 1000 Years Cometh. Not. This claim circulates in the internet and in many mainstream media as well: Scientists have allegedly predicted the coldest winter in 1,000 years for Europe. What is behind it? Nothing – no scientist has predicted anything like it. A Polish tabloid made up the story. An interesting lesson about today´s media. By

Four new papers discuss the relatiosnhip between solar activity and climate: one by Judith Lean (2010) in WIREs Climate Change, a GRL paper by Calogovic et al. (2010), Kulmala et al. (2010), and an on-line preprint by Feulner and Rahmstorf (2010). They all look at different aspects of how changes in solar activity may influence our climate. The paper by Judith Lean (2010) has the character of a re

A quick post for commentary on the new Solomon et al paper in Science express. We’ll try and get around to discussing this over the weekend, but in the meantime I’ve moved some comments over. There is some commentary on this at DotEarth, and some media reports on the story – some good, some not so good. It seems like a topic that is ripe for confusion, and so here are a few quick clarifications th

You are here: Home / Climate Science / The IPCC is not infallible (shock!) Like all human endeavours, the IPCC is not perfect. Despite the enormous efforts devoted to producing its reports with the multiple levels of peer review, some errors will sneak through. Most of these will be minor and inconsequential, but sometimes they might be more substantive. As many people are aware (and as John Niesl

Translations: () This is Hansen et al’s end of year summary for 2009 (with a couple of minor edits). Update: A final version of this text is available here. If It’s That Warm, How Come It’s So Damned Cold? by James Hansen, Reto Ruedy, Makiko Sato, and Ken Lo The past year, 2009, tied as the second warmest year in the 130 years of global instrumental temperature records, in the surface temperature

As many of you will be aware, a large number of emails from the Climatic Research Unit (CRU) at the University of East Anglia webmail server were hacked recently (Despite some confusion generated by Anthony Watts, this has absolutely nothing to do with the Hadley Centre which is a completely separate institution). As people are also no doubt aware the breaking into of computers and releasing priva