My notes are going to be quick as I’m off in a half hour.
I started off with Henry Diaz (of Hughes and Diaz 1994) presenting on Watching the Wwestern Forests Burn. He said that drought has increased in the American West with drought in the past 5 years being the highest (unprecedented) in the last 50 years. He provided various projections of changes in Lee’s Ferry water flow with increased warming ranging from a decline of about 15% to 50%. He said that ponderosa pine was at risk in its present habitat (although these species have migrated habitats for millenia). He said that people “join us” at CIRMOUNT.
I sat through a couple of presentations on the Sierra Nevadas, home of the bristlecones and foxtails. Roger Bales presented minute details of snow cover by elevation — saying that we don’t know much about mountain water cycles, pointing out how snow pack at different elevations contributed to stream flow by month. He observed that snow pillows were at lower altitudes so far and gave little information on high-altitude snow pack. He was asked about whether tree-ring studies at high altitude would help. He said that he had been asking Malcolm Hughes to carry out such studies ofr over 5 years without any success.
The next presenter talked about lapse rates at Yosemite National Park, which on an annual basis were 6.5 deg C km-1, but varied daily. Melt was sometimes synchronous, sometimes not.
Littell presented results from a large study of Douglas fir in Washington througbh Idaho in different elevations and aspects. He said that “water limits tree growth on all scales from stand to region”. They obtained detailed T and P gridcells and found a positiver correlation to precipitation and negative correlation to temperature. The key variable was soil moisture, especially from the prior year; the surplus water gradient was a key variable.
I then browsed posters for a while. I had a long discussion with Bruce Malamud of King’s College London, who had a poster on fractional processes. His background was theoretical; he’d written a big review paper in Adv in Geophys about 8 years ago; he was very anxious to get practical examples. I’ll follow up with him. Barton of Wright State was hosting the NG poster session and unusually greeted the various people who walked by.
The adjacent poster was by Heidi Kuzma, who was comparing formalisms of various multivariate methods: Neural networks; Support Vector Machines; Kriging; Wiener Filters. The linear algebra formalism for Support Vector Machines (which I’ve not studied) looked identical to Ridge Regression.
I had a long and very pleasant chat with Armin Bunde, who was a coauthor with von Storch in a paper on the persistence properties of various reconstructions. In that paper, they considered MM03 as an alternative reconstruction. I twitted him a little on that. However, I told him that I sometimes felt more like a politician, who liked any citation as long as you spelled the name right. He laughed. He knew Benoit Mandelbrot and had some interesting stories.
I walked by a number of posters on ocean sediments — Thornalley; Jian Yu MD01-2378, SO185-10460 in the China Sea; poster PP1598; 1773 showed tephras MD99-2275. Then some posters on radiocarbon reservoir — 1774 had reservoirs of 1200-2000 years with certain species; he said that freshwater weeds were sometimes problematic as they got old carbon through their roots (I’m wondering here about Quelccaya). Other sediment posters: Some others 1727 had radiolarians from ODP Site 1123; 1732 on the Faroe Islands for 16000 years HM03-13325; 1742 from Indonesia MD98-2165. 1753 was on the Illimanni ice core where the last 5 meters of a 136.5 meter core represented 15,000 years.
I went to some ice core presentations on the new EPICA core; missed most Masson-Delmontte’s presentation. Then Kawamura presented on O2/N2 ratio dating arguing that these ratios represented local insolation not climate and could be used to tune core dating (enhancing connections between Dome Fuji and Vostok cores).
I saw Michael Mann on the street walking to lunch. I felt cheerful and called out ” Hi., Mike”. He walked by stony-faced and silent not looking one inch in either direction.
Wolff presented on interglacials. He observed that each interglacial had its own characteristics in terms of temperature, CO2 evolution. Some interglacials were warmer than the present one (up to 3 deg C.) The relative shortness of interglacials — the Holocene is already longish is something that’s worth writing about.
Then I went to a couple of presentations on the East Asian monsoon. A Chinese author said that the mosoon was very strong from 1948-1966 and weak from 1975-1997. This connected with precipitation records.
Zhao PP34B then said, contra L Thompson, that there was negligible correlation between Dasuopu ice accumulation and the All-India Monsoon (IMR). He attributed the negative trend in Dsuopu accumulation over the last 150 years to a weakening of trade winds and long-term changes in the Hadley and Walker circulation.
I then went to another ice core presentation. Masson-Delmonte presented on dD and excess deutrim d in Greenland cores North GRIP and GRIP. Excess deuterium is the residual from the equation
I talked at length off the record with a couple of people. I seem to be controversial in some quarters. I’ll try to get to the Al Gore talk early but it may be hard to get into.