Question on atmospheric forcing variables for CLM

[zhangqr]

Hi all,

I am planning to use meteorological outputs from CESM and GISS to drive the CLM model, but I’m not sure which atmospheric level is appropriate for the forcing variables. In the historical forcing data（historical_met_monthly_GSWP3）, several variables are described as “at the lowest atm level.” Does this refer to the lowest level of the atmospheric model grid, or to near-surface atmospheric conditions?

For example:

float PSRF(time, lat, lon) ;
PSRF:long_name = "surface pressure at the lowest atm level" ;
PSRF:units = "Pa" ;
float QBOT(time, lat, lon) ;
QBOT:long_name = "specific humidity at the lowest atm level" ;
QBOT:units = "kg/kg" ;
float TBOT(time, lat, lon) ;
TBOT:long_name = "temperature at the lowest atm level" ;
TBOT:units = "K" ;
float WIND(time, lat, lon) ;
WIND:long_name = "wind at the lowest atm level" ;
WIND:units = "m/s" ;

Any clarification or guidance would be greatly appreciated. Thanks very much in advance!

 

[oleson]

If you are using atmospheric forcing from CESM, then generally this refers to the lowest level of the atmospheric vertical grid.

 

[zhangqr]

If you are using atmospheric forcing from CESM, then generally this refers to the lowest level of the atmospheric vertical grid.

Thanks, Keith! That's helpful. I understand now.