HR: 15:15h
AN: H53F-06 [Abstracts]
TI: The Role of Irrigation in North American Hydroclimates
AU: * Ozdogan, M
EM: ozdogan@hsb.gsfc.nasa.gov
AF: NASA/GSFC, code 614.3, Greenbelt, MD 20771, United States
AU: Rodell, M
EM: Matthew.Rodell@nasa.gov
AF: NASA/GSFC, code 614.3, Greenbelt, MD 20771, United States
AU: Kato, H
EM: hkato@hsb.gsfc.nasa.gov
AF: NASA/GSFC, code 614.3, Greenbelt, MD 20771, United States
AB:
Irrigation accounts for nearly 80 percent of the world's consumptive use of fresh water, and irrigated croplands
have been shown to influence the terrestrial water balance and land-atmosphere interactions on local to regional
scales. However, these hydrologic and climatic effects are not well quantified, particularly at regional to
continental scales. Furthermore, accurate initialization of land surface moisture and energy states in numerical
weather prediction models is known to enhance short term to seasonal forecast skill, yet there is still room for
improvement. To test and quantify the effects of irrigation and explicit crop types on regional to continental scale
water and energy budgets over the North American Continent, we recently performed experimental simulations
using three land surface models (LSMs), and high-resolution satellite observations of irrigation and crop types.
The three LSMs, Noah, Catchment, and the Common Land Model (CLM), are the land components of the
operational forecast systems of NOAA, NASA's Global Modeling and Assimilation Office (GMAO), and the National
Center for Atmospheric Research, respectively. All three are embedded in NASA's Land Information System (LIS),
which facilitates irrigation-related enhancements while reducing redundancy. LIS enables us to drive the LSMs
at high resolutions in uncoupled and, later, coupled modes, using observation based parameter and forcing
inputs archived by the North American and Global Land Data Assimilation System (LDAS) projects. Preliminary
results indicate enhanced evapotranspiration and reduced heating of the land surface over irrigated sites. These
enhancements lead to improved predictions of state variables such as surface temperature and soil moisture.
Since realistic initialization of land surface states has been shown to be important in weather forecasts, our study
provides insight towards the improvement of operational weather and climate predictions through the treatment of
irrigation in the land surface components of operational prediction systems.
DE: 0480 Remote sensing
DE: 1631 Land/atmosphere interactions (1218, 1843, 3322)
DE: 1803 Anthropogenic effects (4802, 4902)
DE: 1833 Hydroclimatology
DE: 1842 Irrigation
SC: Hydrology [H]
MN: 2007 Joint Assembly