Traducido por Angela Carosio
“en este año hubo un temido presagio. El sol dio su luz sin brillo…y parecía como un sol de eclipse, pues los rayos de luz no eran claros.”
Climate science from climate scientists...
by Gavin
by group
Guest Commentary from Urs Neu
While analyzing tropical cyclone records is difficult enough (see ‘Tropical cylone history – part I’), it is even more challenging to reliably estimate hurricane activity back in time. Recently, Nature published an attempt to reconstruct past major hurricane activity back to 1730 (Nyberg et al. 2007). The authors concluded that the phase of enhanced hurricane activity since 1995 is not unusual compared to other periods of high hurricane activity in the record and thus appears to represent a recovery to normal hurricane activity. The paper was advertised in a press release put out by Nature and received broad media attention.
Although the approach outlined by the authors is interesting, the study contains in my view a number of problems, as outlined in a comment published in Nature today (Neu 2008):
[Read more…] about Tropical cyclone history – part II: Paleotempestology still in its infancy
by group
Guest Commentary from Urs Neu
When discussing the influence of anthropogenic global warming on hurricane or tropical cyclone (TC) frequency and intensity (see e.g. here, here, and here), it is important to examine observed past trends. As with all climate variables, the hurricane record becomes increasingly uncertain when we go back in time. However, the hurricane record has some peculiarities: hurricanes are highly confined structures, so you have to be at the right place at the right time to observe them. Secondly, hurricanes spend most of their life in the open oceans, i.e. in regions where there are very few people and no fixed observations. This means that the reliability of the long-term hurricane record is dependent on who was measuring them, and how, at any given time. The implementation of new observation methods, for example, might have altered the quality of the record considerably. But how much? This crucial question has been widely discussed in the recent scientific literature (e.g. Chang and Guo 2007, Holland and Webster 2007, Kossin et al. 2007, Landsea 2007, Mann et al. 2007). Where do we stand at the moment? This post will concentrate on the North Atlantic, which has the longest record.
[Read more…] about Tropical cyclone history – part I: How reliable are past hurricane records?
by group
Una traducción está disponible aquí
by rasmus
I was honoured to be invited to the annual regional conference for Norwegian journalists, taking place annually in a small town called ‘Hell’ (Try Earth Google ‘Hell, Norway’). During this conference, I was asked to participate in a panel debate about the theme: ‘Climate – how should we [the media] deal with world’s most pressing issue?’ (my translation from Norwegian; by the way ‘Gods expedition’ means ‘Cargo shipment’ in ‘old’ Norwegian dialect).
by Gavin
In the lead up to the 4th Assessment Report, all the main climate modelling groups (17 of them at last count) made a series of coordinated simulations for the 20th Century and various scenarios for the future. All of this output is publicly available in the PCMDI IPCC AR4 archive (now officially called the CMIP3 archive, in recognition of the two previous, though less comprehensive, collections). We’ve mentioned this archive before in passing, but we’ve never really discussed what it is, how it came to be, how it is being used and how it is (or should be) radically transforming the comparisons of model output and observational data.
[Read more…] about The IPCC model simulation archive
by group
Over the past days, many of us have received invitations to a conference called “The 2008 International Conference on Climate Change” in New York. At first sight this may look like a scientific conference – especially to those who are not familiar with the activities of the Heartland Institute, a front group for the fossil fuel industry that is sponsoring the conference. You may remember them. They were the promoters of the Avery and Singer “Unstoppable” tour and purveyors of disinformation about numerous topics such as the demise of Kilimanjaro’s ice cap.
A number of things reveal that this is no ordinary scientific meeting:
“The purpose of the conference is to generate international media attention to the fact that many scientists believe forecasts of rapid warming and catastrophic events are not supported by sound science, and that expensive campaigns to reduce greenhouse gas emissions are not necessary or cost-effective.”
So this conference is not aimed at understanding, it is a PR event aimed at generating media reports. (The “official” conference goals presented to the general public on their website sound rather different, though – evidently these are already part of the PR campaign.)
This is very nice hotel indeed. Our recommendation to those elected officials tempted by the offer: enjoy a great weekend in Manhattan at Heartland’s expense and don’t waste your time on tobacco-science lectures – you are highly unlikely to hear any real science there.
by raypierre
Most of us who are involved in research related to climate change have been asked at one time or another to participate in public debates against skeptics of one sort or another. Some of us have even been cajoled into accepting. In the pre-YouTube days, I did one against the then-head of the American Petroleum institute at the U. of Chicago law school. Gavin did an infamous one against Crichton and company. People are always demanding that Al Gore debate somebody or other. Both Dave Archer and I have been asked to debate Dennis Avery (of “Unstoppable Global Warming” fame) on TV or radio more than once — and declined. It’s a no win situation. If you accept you give the appearance that these skeptics have something to say that’s actually worth debating about — and give their bogus ideas more publicity. If you decline there are all sorts of squawks that “X won’t debate!” or implications that scientists have declared “the debate” (whatever that is supposed to mean) prematurely closed when in fact it is “just beginning.”
Scientists tend to react badly to demands like this in part because the word “debate” is a rather poor description of the way disagreements get hashed out in science. John Ziman has a good discussion of the extent to which scientific questions are ‘debatable’ here (pdf). In a lawyerly debate, it is fair game for each side to pick and choose whatever argument has the most persuasive force with the audience, jury or judge, without any obligation to consider the force of counter-arguments except insofar as they affect one’s defense against the opponent. Science, in contrast, is a deliberative, cooperative, yet still competitive enterprise, where each side is duty bound to fairly consider all arguments and data that bear on the matter at hand. This is not to say that scientific disputes are necessarily dispassionate or orderly. Indeed, I’ve seen near-fistfights break out over things like the Snowball Earth and the interpretation of Neoproterozoic carbon isotope excursions.
The repeated challenges to debate are probably meant to imply that scientists — and their supporters, including Al Gore — are fixed in their ideas, unreceptive to the new and challenging, and unwilling to defend their ideas in public. This picture is hard to square with how scientists actually behave among themselves. It is not that scientists don’t debate, dispute, disagree about matters related to climate. All those things happen, but not on the subjects that skeptics like Inhofe or Fred Singer or Dennis Avery would like to debate (like whether global warming is mainly caused by CO2 or solar variability, or whether the IPCC warming forecasts represent a credible threat.). Those sorts of things are indeed considered settled science by serious climate scientists. Then, too, scientists are justifiably wary of being drawn into staged debates on such diffuse, ill-defined and largely meaningless topics as whether global warming counts as a “crisis.” In the war of the sound bites, the people who feel free to lie and distort can always win. David Mamet made this point eloquently in Bambi vs. Godzilla. A debate like that is not any kind of debate in the sense understood by scientists.
In fact scientists are probing theories and conceptions all the time, trying to break them. The best way to become famous is to overturn established wisdom, so scientists look hard all the time for opportunities to do this. The problem of Hothouse climate states like the Cretaceous and Eocene is a case in point.
[Read more…] about The debate is just beginning — on the Cretaceous!
by Gavin
Una traducción está disponible aquí (pdf)
by Gavin
New rule: When declaring that climate models are misleading in a high profile paper, maybe looking at some model output first would be a good idea.
[Read more…] about New rule for high profile papers
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