Tad Pfeffer, in his Nye Lecture at last year's AGU, explained that no one knows how to model ice sheet dynamics in a convincing way, at the moment.
The AGU video is here <http://vimeo.com/33320811>. http://vimeo.com/33320811 They hand out an award to someone else at the beginning of the video. Tad is introduced starting at 4 minutes ten seconds. The lecture itself starts at 6 minutes and 15 seconds. Some quotes: "...we've been beating the fully deterministic model pretty hard for a lot of years. And, as I said, we're deep into diminishing returns". Discussing other methods, he points out: "These extrapolations are extremely sensitive to what you feed them". Discussing the growth of uncertainty as projections extend out into the future: "in a sense it doesn't matter how far into the future you go, because what you're looking at is simply the shape of a statistical expression". He said: "Does it make any sense to believe these extrapolations going all the way out to 2100? ...in his paper Eric [Rignot] said its probably not a good idea to go all the way, to 2100. And I think it probably is not." He said glaciologists are stepping up to the plate with tremendous efforts to flesh out the data and to come up with something society may find useful. On Sunday, July 8, 2012 7:12:15 PM UTC-7, Ron wrote: > > Ken, Greg and List > > No complaints about anything written below about sea level and > ocean/atmospheric temperatures. But I think it important that we also hear > from list experts on the recent Hansen paper > http://pubs.giss.nasa.gov/docs/notyet/inpress_Hansen_Sato.pdf > on sea levels. Hansen concentrates on a cause not in the paper > identified by Greg (or anything in any IPCC documents) - the breakup of > ice shelves. > > Hansen says he would not be surprised by 5 meters rise by 2095. > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To view this discussion on the web visit https://groups.google.com/d/msg/geoengineering/-/qCLD1VXU90wJ. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
