[This is the remaining set of mental notes on the AGU conference, mostly as a mark for me to look up more later. Because it’s been
a week two weeks, including a week of doing real work to ship products (w00t!), my recollection isn’t as good as it could be.]
Two of the three invited IPCC working group chairs spoke Thursday.
Susan Soloman began with describing the physical science of climate change and how the working groups functioned. A copy of her earlier presentation is worth reading.
The process was described as evaluate peer-reviewed, published research — not doing any of their own. The reports the IPCC produces had multiple levels of vetting with area experts and governments. There was reviewing and re-reviewing. Every single word used had to be agreed upon. This sounds like hell.
Kristie Ebi, an epidemiologist, covered several highly likely changes projected changes in climactic phenomena:
- Higher maximum temperatures, more hot days over land
- Higher minimum temperatures, fewer cold days over land
- More intense precipitation events in the Northern Hemisphere. (Analysis for other areas is conflicting.)
[She did not say, but I heard multiple times elsewhere, that the decline in temperatures during the 50s and 60s was from aerosol pollution.]
[Edit: the folks at Real Climate have a section on this. They also wrote up their AGU thoughts.]
Side effects of these can be seen “on the ground” by locals. Quoting from an earlier presentation she did:
“I work in low-income countries. You go and you talk to people, and they are reporting a significant amount of change. And some of that doesn’t get reflected in the report because of the way the report is structured and carried out.”
Among those she cited:
- Linear increase in salmonella poisoning with higher temperature. She cited 76 million cases of food-borne disease in the US each year.
- Adverse health effects from exposure to more air pollution (SO2, NO2, CO, ozone). Interestingly, warmer climates are projected to increase allergen-producing plant growth.
- Expansion of Lyme disease into Canada
- De-glaciation in Zimbabwe leading to more malaria
- More frequent heat waves. For effect, she showed a slide of the “Taste of Chicago” refrigeration trucks being used to store bodies of heat stroke victims until the coroner could process them.
Roger Pulwarty, who was with working group 2, presented some of his research on snow pack in three areas in the western US. Each area exhibited a trend towards melting sooner in the year. Since snow melt-off supplies water for people and crops, this portends problems with drought. Also, the lack of snowfall decreases albedo, compounding the heating.
Friday morning’s sessions were with the groups doing geothermal research in Yellowstone National Park. YNP is federally chartered (and funded) to study and preserve the geothermal resources. No drilling is permitted, and there are constant battles with the surrounding areas wanting to tap into the geothermal resources.
Many of the measurements have been conducted by probes scattered around the region. These half-minute readings are correlated to geyser and earthquake activity in an attempt to understand more of the park’s geological structure. [One of the more interesting posters had built a thermal probe that utilized two wireless modes: one local for communication with other probes, one longer-range for updating its data with the mothership where it’s put into a MySQL database. Power supply life is estimated to be six months. Cost is still ~$250, though.] They also have been trying to do more remote sensing via airplane and satellite.
Another group examined Chlorofluorocarbon (CFC) and tritium concentrations in springs in an attempt to determine how often groundwater is “recharged” in the park. This tracer technique has been used elsewhere and is pretty fascinating. Quoting from the report:
CFCs provide excellent tracers and dating tools of young water (50 year time scale). [… B]y measuring concentrations of CFC-12, CFC-11 and CFC-113, it is possible to identify groundwater recharged since approximately 1941, 1947, and 1955, respectively. Groundwater dating with CFC-11, CFC-12 and CFC-113 is possible because (1) the atmospheric mixing ratios of these compounds are known and/or have been reconstructed over the past 50 years, (2) the Henry’s law solubilities in water are known, and (3) concentrations in air and young water are relatively high and can be measured.
Water “birth” was estimated via several methods to be around 1974, suggesting the groundwater is likely recharged within the park.
There are estimated to be 4,000 fumaroles (steam vents) in Yellowstone National Park.