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NAMEi.evapo.time - Computes temporal integration of satellite ET actual (ETa) following the daily ET reference (ETo) from meteorological station(s). KEYWORDSimagery, evapotranspiration SYNOPSISi.evapo.time
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DESCRIPTIONi.evapo.time (i.evapo.time_integration) integrates ETa in time following a reference ET (typically) from a set of meteorological stations dataset. Inputs:
representative days calculation: let assume i belongs to range
[DOYmin;DOYmax]
DOYbeforeETa[i] = ( DOYofETa[i] - DOYofETa[i-1] ) / 2 DOYafterETa[i] = ( DOYofETa[i+1] - DOYofETa[i] ) / 2 NOTESETo images preparation: If you only have one meteorological
station data set, the easiest way is:
n=0 for ETo_val in Eto[1] Eto[2] ... do with Eto[1], Eto[2], etc being a simple copy and paste from your data file of all ETo values separated by an empty space from each other. If you have several meteorological stations data, then you need to grid them by generating Thiessen polygons or using different interpolation methods for each day. For multi-year calculations, just continue incrementing DOY values above 366, it will continue working, up to maximum input of 400 satellite images. This is an example of a temporal integration from a weather station as done by Chemin and Alexandridis (2004) ReferencesChemin and Alexandridis, 2004. Spatial Resolution Improvement of Seasonal Evapotranspiration for Irrigated Rice, Zhanghe Irrigation District, Hubei Province, China. Asian Journal of Geoinformatics, Vol. 5, No. 1, September 2004 (PDF) SEE ALSOi.eb.eta, i.evapo.mh, i.evapo.pt, i.evapo.pm, r.sun AUTHORYann Chemin, International Rice Research Institute, The Philippines SOURCE CODEAvailable at: i.evapo.time source code (history) Latest change: Wednesday Nov 27 22:53:26 2024 in commit: b90ce69e88409469369ec1edb86fde8ec822af8b Main index | Imagery index | Topics index | Keywords index | Graphical index | Full index © 2003-2025 GRASS Development Team, GRASS GIS 8.4.1 Reference Manual
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