HR: 1330h
AN: H22B-0915    [PDF]
TI: Modeling Irrigation's Influence on Precipitation in Texas
AU: * Moore, N J
EM: nathan.moore@duke.edu
AF: Div of Earth and Ocean Sciences, Duke University Box 90229, Durham, NC 27708 United States
AU: Rojstaczer, S A
EM: stuart@duke.edu
AF: Div of Earth and Ocean Sciences, Duke University Box 90229, Durham, NC 27708 United States
AU: Avissar, R
EM: avissar@duke.edu
AF: Dept of Civil and Env. Engineering, Duke University, Durham, NC 27708 United States
AB: Irrigation in the Texas High Plains represents an enormous hydrologic disturbance in central North America, with over 6 x 10$^{9}$ m$^{3}$ of irrigation water applied annually to an area of 16,000 km$^{2}$. Previous research has estimated that a 6% to 18% enhancement of summer precipitation is attributable to irrigation. This phenomenon can be explained by the increase in instability and latent heat flux caused by the irrigation water; the contrasting wet and dry surfaces initiate mesoscale convective complexes and result in rainfall. Here we test this influence quantitatively through the use of a mesoscale model (RAMS). Simulations of precipitation produce spatial rainfall patterns and amounts similar to observation. We examine what threshold in irrigation is necessary to significantly influence precipitation patterns by employing a series of simulations using various amounts of irrigation water applied at the surface. Preliminary results from seasonal simulations are also presented.
DE: 1803 Anthropogenic effects
DE: 1833 Hydroclimatology
DE: 1836 Hydrologic budget (1655)
DE: 3322 Land/atmosphere interactions
DE: 3329 Mesoscale meteorology
SC: Hydrology [H]
MN: 2003 Fall Meeting