Gene: You say the paleoclimate record tells us that the Earth will flip into a warm state - increasing its average temperature by almost 10 degrees C from current values? - without GHGs no less! Please connect the dots for me/us on how you arrived at this bold interpretation of the data. Dr. Scotese's website doesn't seem to offer this projection. I would have thought the paleoclimate record suggests a return to another glacial epoch - if we were to ignore the effect of GHGs. So when is your GHG independent warming going to happen? Within the next few decades I presume - clearly this is what you suggest if we need a geoengineering society established now to deal with it.
Glyn On Tue, Apr 19, 2011 at 6:11 AM, Eugene I. Gordon <[email protected]>wrote: > If the documented history of the Earth's climate for the past 450 million > years (see www.scotese.com) has any relevance, the global average > temperature is headed for 25 C, up almost 10 degrees C from current values, > even without the benefit of anthropogenic CO2. Needless to say, but worth > emphasizing, even if we stopped producing CO2 tomorrow and could remove > current excess atmospheric values we are headed for serious climate warming > problems. The social implications are enormous and there is little doubt > that techniques for minimizing the temperature rise will become essential > if > they are not now extremely important. Hence I argue for formalizing the > study of geoengineering techniques/technology before leaping in to do > something about current concerns with a particular approach. Having a > formal > geoengineering society would have immense value. Plant some of the seed. > Don't simply eat it all now. > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Mike MacCracken > Sent: Tuesday, April 19, 2011 12:00 AM > To: Geoengineering > Subject: [geo] On what research I would suggest > > Ken et al.--Note that I am going to focus on SRM approaches here. A word, > however, on CDR, which, it seems to me, is just not at all likely to make > an > important contribution to limiting climate change until global emissions > are > brought down a good bit through efficiency, essentially giving up coal, > etc. > With global C emissions nearing 10 GtC/yr and rising, working on approaches > that at maximum might make it up to sequestering 1-2 GtC/yr is just > premature--we need to take other steps first. The one exception here, it > seems to me, is to see if we can figure out how to deal with ocean > acidification such as through Greg Rau's approach--I'm not sure if that is > more mitigation or not. > > On SRM approaches, as I have been saying for a couple of years, it seems to > me that the highest priority for early research should be on determining if > it is possible to use various of the proposed SRM techniques in very > focused > ways to limit worsening impacts in the near-term (in places like the > Arctic, > the loss of sea ice, ice sheet mass, and permafrost is an emergency now, or > nearly so, and so waiting to move toward implementation seems too hesitant > to me. With this perspective, I would set up a very mission-focused program > goal of coming up with a tested approach for dealing with one or more of > the > most severe impacts, aiming for making a decision to move forward with > implementation starting in of order of five years (so a 5-year research > program to get to the implementation stage, and then ongoing research as > implementation is in progress). > > The types of impacts that I would choose to focus on would include some > combination of the following (and there are of course interlinkages): > generally reducing Arctic warming (which would also lead to some likely > beneficial cooling in mid-latitudes); slowing the loss of ice from the > major > ice sheets; keeping permafrost frozen; redirecting or intensifying seasonal > storm tracks into increasingly arid regions like southwestern North America > and/or Australia; cooling the waters where hurricanes/tropical cyclones > intensify; and similar steps. There are those who argue that nothing can be > done primarily regionally--that everything leads to global responses; > determining whether such global connections are statistically significant > or > not (and whether varying details of the implementation could be done to > reduce them) would be a clear issue to research--including whether what > long-distant linkages there are are beneficial or harmful. > > With focused objectives such as these, I would think that there could be > much more focused environmental and social science research as well--much > more clearly presenting the issue as a risk-risk evaluation than arises in > discussions of future global geoengineering. On the benefit side there > would > at least be a clear beneficial change being sought, which can get much more > confused in the global case. I should also note that I think focusing on > moderating regional-scale impacts, there would hopefully be less of a > tendency to reduce effort on mitigation (if that really is a problem), > because, of course, there are a whole host of impacts not being addressed. > > Not only would success in coming up with an approach for dealing with > severe > impacts such as mentioned above, but it would also help to build > understanding about the various approaches and the basis for ongoing, but > lower priority research on potential global implementation, which I think > should also be considering what I think would be more realistic > implementation scenarios (e.g., implementing incrementally to stop and > slowly reduce radiative forcing starting in the near-term) than imagining > we'd figure out and agree on when some threshold has been passed and do a > large and sudden emergency implementation (not even being clear that when > so > far along everything can be reversed). > > I've written up some of these ideas over the past year or too for various > studies, but had not passed them around, so will attach to this message. > The > first memo offers some thoughts on how I would organize a US program, and > an > accompanying table suggest some specific research efforts. Note that this > memo envisions not just the very focused applied effort, but also an > independent research and evaluation effort to keep make sure questions get > raised and considered--again relating to moving toward the specific > proposed > objective, but in this effort on real and potential shortcomings, and not > just a general research effort (we need more money for that). The second > memo was prepared as a more detailed example of how one might structure the > component of the program aimed at moving rapidly to limit Arctic warming. > It > is posed as a letter dated a few years hence seeking approval for moving > ahead with a major field program to test approaches that have already been > tested in computer simulations, etc. Clearly an optimistic timetable, but > really the type of one that is needed given what seem to be irreversible > changes (like loss of mass from Greenland, loss of biodiversity, etc.) that > we seem headed toward. > > Note that the ideas written up are over a year old, so a bit dated. And > these are just ideas--they would greatly benefit from some intense > discussion about how to do even better, etc. I just think we are moving far > too slowly right now. > > Best, Mike MacCracken > > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > 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/geoengineering?hl=en. > > > -- > You received this message because you are subscribed to the Google Groups > "geoengineering" group. > 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/geoengineering?hl=en. > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. 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