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Open Source EMEP/MSC-W model
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Inputs_LandDefs.csv - global land-cover CROP definition #111

Closed mvieno closed 1 year ago

mvieno commented 1 year ago

Hi, in the Inputs_LandDefs.csv the CROP land type that is included in the glc2000xCLMf18.nc global land cover is defined as follow:

Name,code,type,PFT,... CROP,CROP,SNL,C3PFT,...

should be not something like: Name,code,type,PFT,... CROP,CROP,ECR,NOLPJ,...

Massimo

mifads commented 1 year ago

Hi Massimo,

In Europe the model has "true" crops (well, model ones) which are defined with TC, RC and MC. For these crops we have some attempt at growing seasons which use the latitude model.

The CROPS found in glc2000xCLMf18.nc are for global runs, but although we know crops should be present in those grid squares, we have no idea what they are, or which growing season should be used. Indeed, in many parts of the world several growing-season-harvest cycles may be present in the same grid square, and the type of crop also changed. As we do not have these details, we simply assume that some vegetation is present, but classify that as semi-natural so that some kind of vegetative deposition takes place.

If wanting to model to "realistic" crops (as in Mills et al., GCB, 2018a,b), I use the IAM-type approaches, and add e.g. WinterWheat in every vegetated grid-square, and let somebody else (usually CEH,Katrina) do offline calculations of growing-season and wheat coverage.

mvieno commented 1 year ago

Hi Dave, thanks for the reply. We only needed to have a rough idea of deposition over different land types (fractions). As long the "crops" land type included in the glc2000xCLMf18.nc is roughly representative of where and how much crops; is good enough for what we needed to do. I'll chat with Katrina for a better approach.

Massimo

mifads commented 1 year ago

OK, good. I'll close this issue then. (Just re-open if there is something else needed.)