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Impacts of Climate Change and their mitigation. Bill Menke October 6, 2005. Most of this material drawn from IPCC REPORTS. I’ve saved a copy at my web site … www.ldeo.columbia.edu/users/menke/data/ipcc/index.html You should read the technical summaries … at least !.
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Impacts of Climate Changeand their mitigation Bill Menke October 6, 2005
Most of this material drawn fromIPCC REPORTS I’ve saved a copy at my web site … www.ldeo.columbia.edu/users/menke/data/ipcc/index.html You should read the technical summaries … at least !
Note that global temperatureis predicted to increase by as much as little as1 deg Cor as much as5 deg Cin the next centurywith most models in the2-4 deg Crange
Impact 1 – Spread of Malaria
At what temperatures is malaria present hard to control ?
Impact 2 – Reduction in Arctic Ecosystems
Tundra What temperature Boundary controls The southern extent Of Tundra ?
Impact 3 – Reduction in River Runoff
Hydrologic Cycle: Note land precipitation of 108,000 km3 And that 58% evaporates, with the rest, 46,000 km3, flowing in rivers. But only about 5000 km3 are usable for agriculture
3 deg C Typical land, about 1 meter (40”) of precipitation, 42% (17”) is runoff Now increase temperature 3 deg C (5.3 F), runoff decreases to 14.5”, a drop of 15 percent
Model that takes into account overall climate changes also Predicts regions (e.g. in red) where runoff is down by 15%
Food From Water Caloric need: 2000 kCal per person per day Grain: 4000 kCal per kg 6 Billion People on earth Water needed to grow that grain: 1 m3 per kg Putting it all together, agriculture requires 1100 km3 of water per year as long as we’re all vegetarians
So to feed a world of vegetarians requires about 1/5 of the available runoff a 15% drop in runoff is a very big deal