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shortwave radiation

C

ctcheng@climate_cestm_albany_edu

New Member
Does anyone ever encounter the problem in calculating shortwave radiation? In the subroutine raddedmx, the calculations of alpha (Eq.4.215 in CAM description document) and gamma (4.216) involve the operation of *1./(1-lm**2*coszrs**2), where coszrs is cos of zenith angle and lm=sqrt(3(1.-ws)(1.-ws*gs)) (see Eq.4.219) Therefore, lm can not be equal to 1/coszrs otherwise Inf value will be calculated to crash the model.
I am not familar with the detail of radiation stuff. Does anyone know if lm is definitely smaller than 1 so (1.-lm*coszrs) will definitely not be zero?
 
A

aconley

New Member
This particular piece of code has been tested for many years in many calculations and I have never heard of any problem. At first glance it does appear like there could be a case in which the computation could create an INF or a value outside of the conditions for which the computation was designed. Are you seeing such a condition or do you have reason to believe the computation might be stretched beyond expected input values?
 
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