International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part Bl. Istanbul 2004 
CLOSING THE TERRESTRIAL WATER BUDGET USING REMOTE SENSING 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
     
  
  
NES = E a — E. 3 3 
i {{ ¥ |AW/A=E+T-P-divQ 
: A cy mg 
t A MN Atmospheric Waited Balance 
* p J Joi 
Bn Fadiation _ P Precipitation Microwave. 
Shortwave GOES AA TRV, SOIL GPM 
Longwave AIRS/AMSU I 
E Evaporation/surface Humidity 
H, G Surface Temperagure imd: Microwave / 
AIRS, AVHRR, MODES J Net 
1 
Clouds GOES LAR SAMS Uy Re^ T T Transpiration/ND VI. Visible/NZR t 
i (LE) T C A MODIS, AVHRER, GLI, VCL ( 
T 
RES i ul 4 
CL i E ; U 
1 Se R FunoffFiver Level Laser N 
The land surface HYDRASAT*, TOPEX 
water and energy c i p 
budgets ave linked d c R 
via evapotranspiration AZ * Planning Phase 1 
Teg lt” Groundwater flux : 
n M. NW Water table 
1 
  
  
  
  
  
7 E 
Energy Balance y T MN. y Y Water Balance ó 
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E 
Rn- H+LE+G-0 AZ À /A-P-E-T-R 
  
  
  
  
  
  
  
  
  
  
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Figure 1 Satellite data in the land surface hydrological cycle e 
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The land surface hydrological cycle responds to changes in the moisture stores and r 
the fluxes. Specifically, the satellite sensors detect changes in the stored moisture, either in s 
the atmosphere (In terms of atmospheric water vapor profile) or in the soil as in soil moisture b 
or in lakes/ponds or rivers as changes in water level. These changes are modulated by t 
vegetation changes that are observed by numerous satellite sensors. tl 
The different variables of the hydrological cycle can be sensed using single or a d 
combination of sensors on various satellite platforms. It should be the object of the Jt 
Hydrologic Information Systems to combine information from various sources in a synergistic 
fashion, spanning across differing spatial resolutions and temporal repeats to piece together e 
the entire, land-atmosphere hydrological cycle. i 
With the advent of numerous EOS-era sensors, we will have access to multiple sensors i 
for the same variable. It will therefore be a challenge to catalog these data sets in a proper f 
fashion for usage. is 
The model for use of satellite data would be the derived product rather than the raw ti 
radiances or brightness temperatures or backscatter values. This would overcome the á 
problem for individual investigators to undertake retrieval algorithms and used standardized e 
algorithms for the hydrologic community. a 
Satellite data represent a wealth of information. These bridge the gap between point " 
measurements and computer based simulations. Properly utilized, the satellite data would be C 
of great benefit to the hydrological community. 
S 
IY 
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tc 
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