HR: 0800h
AN: H21H-0833    [Abstracts]
TI: Estimating Sensible Heat in the Great Basin, NV using a Large Aperture Scintillometer
AU: * Conrad, B
EM: conradb3@unlv.nevada.edu
AF: University of Nevada, Las Vegas School Of Life Sciences, 4505 S Maryland Pkwy, Las Vegas, NV 89154, United States
AU: Devitt, D
EM: dev50@clark.nscee.edu
AF: University of Nevada, Las Vegas School Of Life Sciences, 4505 S Maryland Pkwy, Las Vegas, NV 89154, United States
AU: Young, M
EM: michael.young@dri.edu
AF: Desert Research Institue, 755 E. Flamingo Road, Las Vegas, NV 89119, United States
AB: In arid regions such as the southwestern US, where net evaporation exceeds net precipitation, communities are faced with the challenge or providing sufficient water resources to meet the increasing demand. Recent population growth in major cities such as Las Vegas, Nevada, coupled with a continued long-term drought, has led water managers to seek additional water from greater distances. In 2004 a study was initiated to investigate two valleys in the Great Basin, Nevada that could potentially provide additional water to Las Vegas. The goal of the study was to close a water balance on each basin scaling from leaf level measurements to basin wide estimates. The evapotranspiration (ETa) component of the water budget was estimated using an energy balance approach. A large aperture scintillometer (Scintec BLS 5000) was used to measure sensible heat flux with a path length of 1500 m and within the footprint of an eddy flux tower. Additionally, micro-meteorological stations were used to estimate net radiation (Rn) and soil heat flux (G) at two mid point locations along the scintillometer path length. An adjusted R2 of 0.93 between scintillometer and eddy flux sensible heat estimates was found during a diurnal measurement in early spring 2004. Additional runs also accounted for significant amounts of the variation between these two techniques, but at lower R2 values. These results suggest that a scintillometer can be an effective tool for estimating sensible heat over long path lengths of heterogeneous vegetation.
DE: 1813 Eco-hydrology
DE: 1814 Energy budgets
DE: 1818 Evapotranspiration
SC: Hydrology [H]
MN: 2007 Fall Meeting