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Solar spectral stumper

Filed under: — gavin @ 7 October 2010

It’s again time for one of those puzzling results that if they turn out to be true, would have some very important implications and upset a lot of relatively established science. The big issue of course is the “if”. The case in question relates to some results published this week in Nature by Joanna Haigh and colleagues. They took some ‘hot off the presses’ satellite data from the SORCE mission (which has been in operation since 2003) and ran it through a relatively complex chemistry/radiation model. These data are measurements of how the solar output varies as a function of wavelength from an instrument called “SIM” (the Spectral Irradiance Monitor).
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What we can learn from studying the last millennium (or so)

Filed under: — mike @ 15 May 2010 - (Español) (English)

With all of the emphasis that is often placed on hemispheric or global mean temperature trends during the past millennium, and the context they provide for interpreting modern warming trends, one thing is often lost in the discussion: space matters as much as time. Indeed, it is likely that the regional patterns of past climate changes, rather than simple hemispheric or global mean temperature trends, will best inform our understanding of the dynamical mechanisms involved. Since much of the uncertainty in future projections relates to regional climate change impacts, it makes particular sense to focus on those changes in the past that involve regional changes and the underlying mechanisms behind them.

For instance, melting of the cryosphere (and consequent rises in sea level), subtle shifts in drought and rainfall patterns, and extreme events, are all regional effects that could be important threats to ecosystems and our environment. Such changes are often associated with phenomena like ENSO or the North Atlantic Oscillation. Yet there remain large uncertainties about how such mechanisms will respond to anthropogenic climate change.

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More on sun-climate relations

Filed under: — rasmus @ 9 March 2010

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.

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Something Is X in the State of Denmark

Filed under: — rasmus @ 29 November 2009

We received a letter with the title ‘Climate Change: The Role of Flawed Science‘ which may be of interest to the wider readership. The author, Peter Laut, is Professor (emeritus) of physics at The Technical University of Denmark and former scientific advisor on climate change for The Danish Energy Agency. He has long been a critic of the hypothesis that solar activity dominates the global warming trend, and has been involved in a series of heated public debates in Denmark. Even though most of his arguments concern scientific issues, such as data handling, and arithmetic errors, he also has much to say about the way that the debate about climate change has been conducted. It’s worth noting that he sent us this letter before the “CRU email” controversy broke out, so his criticism of the IPCC for being too even handed, is ironic and timely.

Update – the link in the letter is now fixed. -rasmus

Why the continued interest?

Filed under: — rasmus @ 9 October 2009

I believe the idea that galactic cosmic rays (GCR) play a role for the present global warming is unlikely to fade soon, despite a growing number of scientific arguments that normally would falsify a hypothesis and lay it dead (see links here and here). Despite all the arguments against the role of GCR, there was a solicited talk about ‘cosmoclimatology’ at the European Meteorological Society’s (EMS) annual meeting in Toulouse. Henrik Svensmark is further invited by the Norwegian Academy of Science and Letters (NASL) to provide an introduction to their seminar on climate. So why is the GCR-hypothesis still perceived as an interesting explanation?

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