surface evaporation (AEVAP_S) – in #9: CCLM

in #9: CCLM

Hey, I use cclm5.0_clm1.
When I look at my AEVAP _S (surface evaporation) variable it seems to me that a [negative value equals evaporation] and a [positive value equals condensation]?
Is this correct? (if yes, is this a misleading name of the variable or based on some useful conventions?)

Cheers
Rolf

  @rolfzentek in #dc3e7bb

Hey, I use cclm5.0_clm1.
When I look at my AEVAP _S (surface evaporation) variable it seems to me that a [negative value equals evaporation] and a [positive value equals condensation]?
Is this correct? (if yes, is this a misleading name of the variable or based on some useful conventions?)

Cheers
Rolf

surface evaporation (AEVAP_S)

Hey, I use cclm5.0_clm1.
When I look at my AEVAP _S (surface evaporation) variable it seems to me that a [negative value equals evaporation] and a [positive value equals condensation]?
Is this correct? (if yes, is this a misleading name of the variable or based on some useful conventions?)

Cheers
Rolf

View in channel

In COSMO it is convention that fluxes to the surface are in general positive, fluxes from the surface are negative.
For the latent heat flux it can be made clear by the standard_name:

	float ALHFL_S(time, rlat, rlon) ;
		ALHFL_S:standard_name = “surface_downward_latent_heat_flux” ;


There is no standard_name for evaporation containing “upward” or “downward” as far as I know. However, this is a good point you make. CF-conventions allow to add a “positive” attribute. Therefore the following would be a possible alternative:

	float AEVAP_S(time, rlat, rlon) ;
		AEVAP_S:standard_name = “water_evaporation_amount” ;
		AEVAP_S:positive = “down” ;

  @burkhardtrockel in #fb0d198

In COSMO it is convention that fluxes to the surface are in general positive, fluxes from the surface are negative.
For the latent heat flux it can be made clear by the standard_name:

	float ALHFL_S(time, rlat, rlon) ;
		ALHFL_S:standard_name = “surface_downward_latent_heat_flux” ;


There is no standard_name for evaporation containing “upward” or “downward” as far as I know. However, this is a good point you make. CF-conventions allow to add a “positive” attribute. Therefore the following would be a possible alternative:

	float AEVAP_S(time, rlat, rlon) ;
		AEVAP_S:standard_name = “water_evaporation_amount” ;
		AEVAP_S:positive = “down” ;

In COSMO it is convention that fluxes to the surface are in general positive, fluxes from the surface are negative.
For the latent heat flux it can be made clear by the standard_name:

	float ALHFL_S(time, rlat, rlon) ;
		ALHFL_S:standard_name = “surface_downward_latent_heat_flux” ;


There is no standard_name for evaporation containing “upward” or “downward” as far as I know. However, this is a good point you make. CF-conventions allow to add a “positive” attribute. Therefore the following would be a possible alternative:

	float AEVAP_S(time, rlat, rlon) ;
		AEVAP_S:standard_name = “water_evaporation_amount” ;
		AEVAP_S:positive = “down” ;