WAsP 12.9 updates - T* stability, geostrophic shear and others

[Reuven Shenkar]

Dear WAsP team,

I just started working with a freshly-installed WAsP 12.9 after many years with WAsP 11. I was surprised to find quite a few changes, the following seem to be the main ones as far as I am concerned. Could you please provide more details? I could not find much documentation, other than a short description in the release notes.

1. Legacy vs. "new" IBZ - meaning and significance?

2. Possibility of editing default wind atlas structure now both in project and GWC (and seems they do not synchronize with each other in either direction?). Could you please explain the behavior of this setting. Also, is it still the standard recommendation to modify the heights and roughness values to match the main project specific values?

3. New stability model T* + properties are now filled in the GWC stability tab, for both the legacy and the new model. Could you please explain about the T* model, and perhaps provide some references?

4. Geostrophic shear tab - could you please provide some more details on that. Does turning it off mean falling back on the legacy WAsP model?

 

Thanks,

Reuven

 

[Rogier]

Hi,

1) The new IBZ can also deal with displacement heights in case of forests. It is probably most easy to understand the differences from Fig 1 and 2 in this paper:
https://wes.copernicus.org/articles/6/1379/2021/. If you are not using displacement heights the results should be nearly identical, although the new routines also solves some problems with the old routines where "dead pixels" were occurring in the resource grid in some rare cases. You can how to use it here:
https://panopto.dtu.dk/Panopto/Pages/Viewer.aspx?id=0394a399-d5c2-4a71-9954-b0d800dbcb7f

2) Yes you can also right click on the GWC now, because that was a more logical place to edit this. You will have to recalculate the GWC after you have changed the heights, because the results will be different.

3) Yes the T* model uses modelled stability parameters from ERA5 to get a overview of sectorwise stability based on the location of the site. It will lookup the nearest ERA5 grid point and retrieve the related stability and boundary layer height. This approach was validated to be better then the old method, see here:
https://www.wasp.dk/news/nyhed?id=ea5c4c79-c096-4cc4-a771-ad5314b837ef
https://link.springer.com/article/10.1007/s10546-023-00803-3

4) Yes these changes are described here:
https://www.wasp.dk/news/nyhed?id=662f23ca-b559-418a-8879-e6b281b7a31f

Regards

 

 

[Reuven Shenkar]

Many thanks, Rogier!