HR: 11:00h
AN: GC22A-03 [Abstracts]
TI: Effects of Land Use on Energy Budget in the Semi-Arid Region of Inner Mongolia, China
AU: * Chen, J
EM: Jiquan.Chen@utoledo.edu
AF: University of Toledo, 2801 W. Bancroft Street
MS 604, Toledo, OH 43606, United States
AB:
The objectives of this paper are to mechanistically explain the variability of energy (Rn, L, G, Q, H, T) and water
(ET, E, EF, Tr, LWSI, Wleaf, M) fluxes along a climatic and land use gradient using a network of in situ eddy flux
towers and examine the spatial variability of Rn and G in contributing energy enclosure to better incorporate land
surface characteristics in modeling regional water and energy balances. Energy balance closure for the study
sites ranged from 0.75 to 0.89 (30-min scale), from 0.87 to 1.04 (daily scale), and from 0.91 to 1.10 (annual
scale). The seasonal changes in Rn, LE, Hs and G of the four sites were similar, with very low values during the
snow cover from December to February and increasing trend in the growing season. The energy enclosure had a
daily average residual of 8-19 W m-2 with an ordinary least squares slope of 83-96%, and the largest
residual of 50-70 W m-2 with replicates at large scales. This enclosure variation was larger due to G than to
Rn. The uncertainty associated with Rn was 18 W m-2 (5% of Rn) at midday and 11 W m-2 (13%) for
daily mean, while G was 60 W m-2 (13%) at midday and 27 W m-2 (35%) for daily mean. The maximum
spatial variation integrating Rn and G contributing to energy enclosure was near 40 W m-2 (40%) on daily
base. When linking the above ground measurements with MODIS, we assesed how land use change changes
the energy budget of the region. The results allow us to partition the transpiration and evaporation from ET.
DE: 0480 Remote sensing
DE: 0495 Water/energy interactions (1878)
DE: 0758 Remote sensing
DE: 0764 Energy balance
DE: 1632 Land cover change
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting