HR: 10:30h
AN: GC52A-02 INVITED    [Abstracts]
TI: Effects of Mount Pinatubo Volcanic Eruption on the Hydrological Cycle as an Analog of Geoengineering
AU: Trenberth, K E
EM: trenbert@ucar.edu
AF: National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307, United States
AU: * Dai, A
EM: adai@ucar.edu
AF: National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307, United States
AB: The problem of global warming arises from the buildup of greenhouse gases (GHGs) such as carbon dioxide from burning of fossil fuels and other human activities that change the composition of the atmosphere and alter outgoing longwave radiation (OLR). One geoengineering solution being proposed is to reduce the incoming sunshine through emulating volcanic eruptions by injecting large amounts of aerosols into the stratosphere. Different characteristics of the forcing induced by the increased GHGs and stratospheric aerosols have the potential to cause unintended responses in the climate system, and thus they require careful studies. Here we use the large volcanic eruption of Mount Pinatubo as an analog of potential effects on the terrestrial hydrological cycle from similar geoengineering solutions to global warming. Precipitation and streamflow records from 1950 to 2004 are examined for the effects of volcanic eruptions from Agung in May 1963, El Chichón in March 1982, and Pinatubo in June 1991, taking into account effects from El Niño-Southern Oscillation. Following the eruption of Mount Pinatubo in June 1991 there was a substantial decrease in precipitation over land and a record decrease in runoff and river discharge into the ocean from October 1991-September 1992 caused by wide-spreading drying over land. The results suggest that major adverse effects, including drought, could arise from geoengineering solutions emulating large volcanic eruptions.
UR: http://www.cgd.ucar.edu/cas/adai/papers/TrenberthDai_GRL07.pdf
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1655 Water cycles (1836)
DE: 1854 Precipitation (3354)
DE: 1860 Streamflow
DE: 8409 Atmospheric effects (0370)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting