HR: 0800h
AN: H41D-0430    [Abstracts]
TI: Impacts of land use change on California's climate
AU: * Kanamaru, H
EM: hkanamaru@ucsd.edu
AF: Experimental Climate Prediction Center, Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093-0224 United States
AU: Kanamitsu, M
EM: kana@ucsd.edu
AF: Experimental Climate Prediction Center, Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093-0224 United States
AB: California has seen a huge change in land use since mid-1800s with a sharp increase in population. The Regional Spectral Model of ECPC at Scripps Institution of Oceanography is used to investigate the impact of land use change on California's climate. The model is run at 25km resolution for 1995-1996 with NCEP/DOE Reanalysis 2 as boundary conditions. The experiment compares two runs with different land cover datasets: 1) pre-1890 natural vegetation land surface, and 2) modern land surface with irrigation and urbanization. In addition, ensemble runs are performed to see how initial model variability adds uncertainty to the interpretation of differences between modern and pre-industrial runs. Urban areas are investigated at 10km resolution. One notable difference is a decrease of the mean temperature in the irrigated land from presettlement to modern run in summer. Daily maximum temperature decrased more than minimum temperature, resulting in a reduced diurnal temperature range. We discuss the role that past land use/cover changes and irrigation may have had on California's climate through the analysis of model response to the changes.
DE: 1622 Earth system modeling (1225)
DE: 1626 Global climate models (3337, 4928)
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
DE: 1632 Land cover change
SC: Hydrology [H]
MN: Fall Meeting 2005