Information on STD_ELEV

[Yonas]

Hi all,

I only found 'STD ELEV' (standard deviation of elevation) in the CLM surface dataset, and the documentation says it is calculated from a 1km HYDRO1K DEM in the Snow Hydrology section. I'm curious why CLM uses 'STD ELEV' rather than actual elevation data, especially in areas where there is no snow at all. Where can we find the original elevation data that was used to calculate 'STD ELEV'?

Thanks!

 

[oleson]

STD_ELEV is calculated from a 1km DEM using the mksurfdata_map tool (USGS HYDRO1K 1-km dataset (Verdin and Greenlee 1996)):

2.2. Surface Characterization, Vertical Discretization, and Model Input Requirements — ctsm CTSM master documentation

As you noted, it is used in the snow cover fraction parameterization:

2.8. Snow Hydrology — ctsm CTSM master documentation

The gridcell topography is provided by the topography file specified in datm.streams.txt.topo.observed.

 

[Yonas]

STD_ELEV is calculated from a 1km DEM using the mksurfdata_map tool (USGS HYDRO1K 1-km dataset (Verdin and Greenlee 1996)):

2.2. Surface Characterization, Vertical Discretization, and Model Input Requirements — ctsm CTSM master documentation

As you noted, it is used in the snow cover fraction parameterization:

2.8. Snow Hydrology — ctsm CTSM master documentation

The gridcell topography is provided by the topography file specified in datm.streams.txt.topo.observed.

Thank you, for the brief explanation!!!