|
Titel |
Mapping daily evapotranspiration at field to continental scales using geostationary and polar orbiting satellite imagery |
VerfasserIn |
M. C. Anderson, W. P. Kustas, J. M. Norman, C. R. Hain, J. R. Mecikalski, L. Schultz, M. P. González-Dugo, C. Cammalleri, G. D'Urso, A. Pimstein, F. Gao |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1027-5606
|
Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 15, no. 1 ; Nr. 15, no. 1 (2011-01-21), S.223-239 |
Datensatznummer |
250012598
|
Publikation (Nr.) |
copernicus.org/hess-15-223-2011.pdf |
|
|
|
Zusammenfassung |
Thermal infrared (TIR) remote sensing of land-surface temperature (LST)
provides valuable information about the sub-surface moisture status required
for estimating evapotranspiration (ET) and detecting the onset and severity
of drought. While empirical indices measuring anomalies in LST and
vegetation amount (e.g., as quantified by the Normalized Difference
Vegetation Index; NDVI) have demonstrated utility in monitoring ET and
drought conditions over large areas, they may provide ambiguous results when
other factors (e.g., air temperature, advection) are affecting plant
functioning. A more physically based interpretation of LST and NDVI and
their relationship to sub-surface moisture conditions can be obtained with a
surface energy balance model driven by TIR remote sensing. The
Atmosphere-Land Exchange Inverse (ALEXI) model is a multi-sensor TIR
approach to ET mapping, coupling a two-source (soil + canopy) land-surface
model with an atmospheric boundary layer model in time-differencing mode to
routinely and robustly map daily fluxes at continental scales and 5 to 10-km
resolution using thermal band imagery and insolation estimates from
geostationary satellites. A related algorithm (DisALEXI) spatially
disaggregates ALEXI fluxes down to finer spatial scales using moderate
resolution TIR imagery from polar orbiting satellites. An overview of this
modeling approach is presented, along with strategies for fusing information
from multiple satellite platforms and wavebands to map daily ET down to
resolutions on the order of 10 m. The ALEXI/DisALEXI model has potential for
global applications by integrating data from multiple geostationary
meteorological satellite systems, such as the US Geostationary Operational
Environmental Satellites, the European Meteosat satellites, the Chinese
Fen-yung 2B series, and the Japanese Geostationary Meteorological
Satellites. Work is underway to further evaluate multi-scale ALEXI
implementations over the US, Europe, Africa and other continents with
geostationary satellite coverage. |
|
|
Teil von |
|
|
|
|
|
|