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Weather data derived from satellite imagery are getting better every year. The satellite imagery record that has been built up from the nineteen seventies now enables the calculation of normals as well. Although satellite derived data cannot be a substitute for ground data, these data are often the only possibility to run a water balance model, due to lack of ground data. | Weather data derived from satellite imagery are getting better every year. The satellite imagery record that has been built up from the nineteen seventies now enables the calculation of normals as well. Although satellite derived data cannot be a substitute for ground data, these data are often the only possibility to run a water balance model, due to lack of ground data. | ||
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These satellite-derived data can be used in AgrometShell after importing them. This can be done in the following way: | These satellite-derived data can be used in AgrometShell after importing them. This can be done in the following way: | ||
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|width="300"|The new data will be extracted from the image. To check whether the data have been imported, use the ''Data – Inventory'' function.||[[Image:graph36.jpg|400px|]] | |width="300"|The new data will be extracted from the image. To check whether the data have been imported, use the ''Data – Inventory'' function.||[[Image:graph36.jpg|400px|]] | ||
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+ | The same function can also be used to import altitude data from a Digital Terrain Model (DTM). | ||
=''' Entering weather data from ASCII files'''= | =''' Entering weather data from ASCII files'''= |
Revision as of 08:08, 18 August 2006
Contents
Entering and importing weather and crop data.
After a network has been created, crop data can be entered by hand. In principle this is possible for grid-based networks and station networks alike. However as grid-based networks do not coincide with a ground network, it will usually not make sense to enter data manually.
Entering weather data manually
As the FAO water balance model is usually run with a 10-day (dekadal) time step, this example will show how to enter dekadal data.
All weather data for all time periods (daily, decadal and monthly data) can be entered in the same way.
Entering weather data from images
Weather data derived from satellite imagery are getting better every year. The satellite imagery record that has been built up from the nineteen seventies now enables the calculation of normals as well. Although satellite derived data cannot be a substitute for ground data, these data are often the only possibility to run a water balance model, due to lack of ground data.
These satellite-derived data can be used in AgrometShell after importing them. This can be done in the following way:The same function can also be used to import altitude data from a Digital Terrain Model (DTM).
Entering weather data from ASCII files