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nansencenter / openwind

A python package for estimating high resolution wind from SAR images
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Add possibility to retrieve model wind field data from an online service. #1

Closed mortenwh closed 10 years ago

mortenwh commented 11 years ago

Presently, the code uses local paths for the model wind field information and thus only works on my local system. Other users need to modify the model wind class. This should be done by making use of online archives at met.no or others...

knutfrode commented 10 years ago

The present model_wind module fetches wind files (NCEP, Hirlam) from a local folder/filename-structure.

Such structure will however be specific for each institution/user, so therefore the model_wind module will instead be updated to download wind from an (or several) online source - of particular use for non-experts, or users not having access to local wind direction data.

One promising online resource is the NCEP GFS available through NOMADS: http://nomads.ncdc.noaa.gov/data.php#hires_weather_datasets http://nomads.ncdc.noaa.gov/data/gfs4/ (global, 0.5 degree, 3 hour resolution)

The module may download (part of) the wind files (GRIB2) locally, and use this for the SAR wind calculations. The data seem not to be available through Thredds, and thus download of physical files seems necessary. Each file is ~50MB, but contains many variuables/levels - thus the script will download only a subset of the files to save space/bandwidth.