How is deposition mechanism considered in extreme high temperature

CMAQ Chemistry and Aerosols
1

Hi, I would like to inquire about the mechanism of dry deposition in the CMAQ model. Does the model consider the impact of vegetation stomatal closure under extreme high temperatures on dry deposition? How is this mechanism accounted for in the model?

2

Oh, please show some guidance to me

3

Dry deposition in CMAQ uses the stomatal conductance from the LSM in WRF. We typically use the PX LSM option in WRF. The PX LSM computes the bulk stomatal conductance using the Jarvis method with emperical functions for air temperature, air humidity, soil moisture, and solar radiation. The PX LSM is described in Pleim and Xiu 1995, Xiu and Pleim 2001, and Pleim and Xiu 2003. the air temperature function looks like:

image
image631×686 23.2 KB

So you can see that the stomatal function shuts down at extremely high temperatures

3 Likes
4

Thanks a lot for your prompt reply. It does help ~