EGSC WaterSMART -irrigation water use research
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Transcript of EGSC WaterSMART -irrigation water use research
EGSC WaterSMART-irrigation water use research
John W. JonesUSGS Eastern Geographic Science Center
March 08, 2012
Input for the ACF WaterSMART Stakeholders meeting
How much (which) land is irrigated?
Create maps of water evaporation from satellite imagery.
Irrigated land = high demand and high evaporation and cropland.
Test map accuracy through comparison with GaMP data and irrigation demand analysis.
How much water is evaporating in irrigated areas?
Create maps of water evaporation from satellite imagery.
Interpolate instantaneous evaporation between image dates.
Sum evaporation by location. Compare against GaMP, ground-based
evaporation measurements and hydrologic model estimates.
Mississippi County AR Goal: apportion ground measured annual total irrigation to growing season dates.
Evaporation example from AR / MS pilots
Yazoo delta MS Goal: Extrapolate limited monitoring data to entire region and longer time frames.
Surface temperature on June 26, 2009.
Mississippi County, Arkansas outline shown in black.
Remote sensing approach uses satellite based surface temperature
Vegetation Index (NDVI) for June 26, 2009.
Mississippi County, Arkansas outline shown in black.
Remote sensing approach uses satellite based estimates of vegetation amount
A – HIGH Evapotranspiration (little difference between surface and air temperature)B – low Evapotranspiration (large temperature difference over dense vegetation)C – HIGH soil Evaporation (small temperature difference over bare ground)D – low soil Evaporation (large temperature difference over bare ground)
Vegetation amount (NDVI) vs. temperature of the surface (Ts) – temperature of the air (Ta)
Mississippi County, Arkansas boundary shown in black.
June 21 2009 evapotranspiration
Progress to-date
Specific GA study area selected (Spring and Ichawaynochaway Creeks)
Landsat imagery selected, acquired and calibrated to at-surface reflectance.
Two major components of analysis have been coded for batch processing.
Challenge: Discovered cloud/cloud shadow screening “glitch” is being corrected.
Progress to-date
Image database (to-date):
Year Landsat 5 Landsat 7 Total
2007 9 7 16
2008 4 9 13
2009 11 8 19
2010 14 15 29
Total 38 39 77