How to output apparent heating and apparent moisture sink in CAM?

[xiexinyls@gmail_com]

Hi,

I am a CAM2 user and I really need you help:) I would like to
calculate the apparent heating Q1 and apparent moisture sink Q2
in the model results and compare it with the sounding observation
data. I read the Yanai 1973 paper and got the formula for Q1 and Q2.
It has two possible forms. It seems that one can calculate the time
difference plus advection plus vertical advection of dry static
energy to get Q1. Or one can sum all the related terms of temperature
in each of the physical parts to obtain
Q1. If I use the first method, the approximation of spacial
differentials would be a problem. And I need to figure out which
physical variable is needed to output (I found a lot of the output
vars). I very much would like to know how you usually calculate Q1 and
Q2 for CAM.

Thank you very much!

 

[hannay]

For temperature, the total physics tendecy is: PTTEND with:
PTTEND = DTCOND + QRS +QRL + DTV + TTGWORO
where:
DTCOND - Precipitation physics tendency
QRS - Solar heating rate
QRL - Longwave heating rate
DTV - Vertical diffusion tendency
TTGWORO - Gravity wave tendency

For moisture, the total physics tendency is PTEQ with:
PTEQ = DCQ + VD01 + DMEQ
DCQ - Tendency from precipitation physics
VD01 - Vertical diffusion tendency
DMEQ - This term is from a process described as Tendency of q to
conserve water (Section 3.3.6, pg. 71 of CAM3 Description,
NCAR/TN-464+STR.)

 

[xiexinyls@gmail_com]

Thank you very much! hannay
Your specific answer was a great help!

For temperature, the total physics tendecy is: PTTEND with:
PTTEND = DTCOND + QRS +QRL + DTV + TTGWORO
where:
DTCOND - Precipitation physics tendency
QRS - Solar heating rate
QRL - Longwave heating rate
DTV - Vertical diffusion tendency
TTGWORO - Gravity wave tendency

For moisture, the total physics tendency is PTEQ with:
PTEQ = DCQ + VD01 + DMEQ
DCQ - Tendency from precipitation physics
VD01 - Vertical diffusion tendency
DMEQ - This term is from a process described as Tendency of q to
conserve water (Section 3.3.6, pg. 71 of CAM3 Description,
NCAR/TN-464+STR.)

 

[QINKONG]

For temperature, the total physics tendecy is: PTTEND with:
PTTEND = DTCOND + QRS +QRL + DTV + TTGWORO
where:
DTCOND - Precipitation physics tendency
QRS - Solar heating rate
QRL - Longwave heating rate
DTV - Vertical diffusion tendency
TTGWORO - Gravity wave tendency

For moisture, the total physics tendency is PTEQ with:
PTEQ = DCQ + VD01 + DMEQ
DCQ - Tendency from precipitation physics
VD01 - Vertical diffusion tendency
DMEQ - This term is from a process described as Tendency of q to
conserve water (Section 3.3.6, pg. 71 of CAM3 Description,
NCAR/TN-464+STR.)

Hi Hannay! This is Qin from Purdue. I'm running a ETEST control and tropical deforestation simulation for my climate modeling course project. As part of the project, we want to examine precipitation change by doing a slice equilibrium comparison and explain why. We did the following derivations regarding moisture balance. We want use the final equation to explain why precipitation increase or decrease locally. However, we have a few confusions:

(1) We feel hesitant about how to interpret the A and B term in the final equation. Can we interpret A term as the effects of advection by synoptic-scale systems, and B term as the effects of local divergence or convergence? Or is there any better way to classify the potential factors that contribute to precipitation changes?

(2) For A and B term, which CAM history field should we look at?

Thanks a lot!

-Qin