Eric Swanson <[email protected]> said: > Igor, are you responding to my post?
Sorry Eric, I should have made it clear. My post was addressed to Robert. The first part was an elaboration on what you said: "The Younger Dryas started with a well known single event, a flood of fresh water related to the melting of the glaciers over Canada. That event is not repeatable in the present situation, thus it is not partof some chaotic oscillation, or what ever you are trying to claim it is. " The second part was a question for Robert. Eric Swanson <[email protected]> said: > I haven't read the paper in the PNAS by Kyle Swanson, et al., as it's behind > a pay wall. But, from the information I've seen, it sure looks like the > Earth is experiencing a warming trend. Indeed. I wanted to see if Robert agrees with Swanson and Tsonis that there is "externally forced climate signal, which is monotonic, accelerating warming during the 20th century". On Jan 30, 10:24 am, Igor Samoylenko <[email protected]> wrote: > It is not just Younger Dryas but also numerous other abrupt climate jumps > during the last Ice Age cycle known as Dansgaard-Oeschger and Heinrich events > are all thought to be linked to fresh-water fluxes and resulting disruption > of North Atlantic deep water formation. There is a lot of literature on this > topic, but here is a good summary paper: > > Alley, R.B. Wally Was Right: Predictive Ability of the North Atlantic > “Conveyor Belt” Hypothesis for Abrupt Climate Change. Earth and Planetary > Sciences35, 241-272 (2007). > http://shadow.eas.gatech.edu/~kcobb/abrupt/alley07.pdf. > > "Linked, abrupt changes of North Atlantic deep water formation, North > Atlantic sea ice extent, and widespread climate occurred repeatedly during > the last ice age cycle and beyond in response to > changing freshwater fluxes and perhaps other causes. This paradigm, developed > and championed especially byW.S. Broecker, has repeatedly proven to be > successfully predictive as well as explanatory with > high confidence. Much work remains to fully understand what happened and to > assess possible implications for the future, but the foundations for this > work are remarkably solid." > > Chris Turney has a whole chapter on this in his book Ice, Mud and Blood > Lessons from the climate past. > > As forTsonisandSwanson, you are of course aware of their recent paper: > > Swanson, K.L., Sugihara, G. &Tsonis, A.A. Long-term natural variability and > 20th century climate change. Proceedings of the National Academy of > Sciences106, 16120-16123 (2009). > http://www.pnas.org/content/106/38/16120.abstract > > "Global mean temperature at the Earth's surface responds both to > externally imposed forcings, such as those arising from anthropogenic > greenhouse gases, as well as to natural modes of variability internal > to the climate system. Variability associated with these latter > processes, generally referred to as natural long-term climate > variability, arises primarily from changes in oceanic circulation. Here > we present a technique that objectively identifies the component of > inter-decadal global mean surface temperature attributable to natural > long-term climate variability. Removal of that hidden variability from > the actual observed global mean surface temperature record delineates > the externally forced climate signal, which is monotonic, accelerating > warming during the 20th century." > > So, do you accept that (having removed natural variability) we have > externally forced climate signal, which is monotonic, accelerating warming > during the 20th century? I haven't read the paper in the PNAS by Kyle Swanson, et al., as it's behind a pay wall. But, from the information I've seen, it sure looks like the Earth is experiencing a warming trend. I can't speak for Robert... E. S. --- -- You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/globalchange -- You received this message because you are subscribed to the Google Groups Global Change ("globalchange") newsgroup. Global Change is a public, moderated venue for discussion of science, technology, economics and policy dimensions of global environmental change. Posts will be admitted to the list if and only if any moderator finds the submission to be constructive and/or interesting, on topic, and not gratuitously rude. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/globalchange
