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Center for Nonlinear Studies |
Since the 2006 IPCC 4th Scientific Assessment Review (4AR), it is generally agreed that what I will call the First Order questions have been answered about whether humans, through their emissions of Carbon Dioxide and other so-called GreenHouse Gases (GHGs), are causing significant warming of the climate. Since then, the community has turned increasingly to second order issues. As examples of both-- * 1st order-- humans are warming the climate in a way that could present significant problems for society if kept up. 2nd Order--just how fast is the climate expected to warm, i.e. how sensitive to GHG forcing?... * Solar forcing is small and so not expected to be a major modifier of climate compared with GHG forcing, but exactly what is the magnitude of solar forcing, and in particular, is there an indirect forcing component over and above changes in solar radiation? * Finally,there is considerable interest in an apparent 60 yr. multi-decadal oscillation in the Atlantic Ocean that seems to correlate with warming and cooling during the 20th Century and may be causing some of it, because, if this is true, then there is a larger natural component to recent warming (and lack thereof) than previously thought which would mean that GHG warming might be a bit slower than currently accepted. Many of these issues came up in LANL's recent Santa Fe Climate Conference. This talk will review the first order questions and their answers, and then update listeners on the status of important second order ones.
Host: Robert Ecke, CNLS, 667-1444, ecke@lanl.gov