MODULE obs_def_dew_point_mod
Overview
Provides a subroutine to calculate the dew point temperature from model temperature, specific humidity, and pressure.
Revision 2801 (April 2007) implements a more robust method (based on Bolton’s Approximation) for calculating dew point. This has been further revised to avoid a numerical instability that could lead to failed forward operators for dewpoints almost exactly 0 C.
Other modules used
types_mod
utilities_mod
location_mod (most likely threed_sphere)
assim_model_mod
obs_kind_mod
Public interfaces
use obs_def_dew_point_mod, only : |
get_expected_dew_point |
A note about documentation style. Optional arguments are enclosed in brackets [like this].
call get_expected_dew_point(state_vector, location, key, td, istatus)
real(r8), intent(in) :: state_vector
type(location_type), intent(in) :: location
integer, intent(in) :: key
real(r8), intent(out) :: td
integer, intent(out) :: istatus
Calculates the dew point temperature (Kelvin).
|
A one dimensional representation of the model state vector |
|
Location for this obs |
|
Controls whether upper levels (key = 1) or 2-meter (key = 2) is required. |
|
The returned dew point temperature value |
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Returned integer describing problems with applying forward operator |
Files
NONE
References
Bolton, David, 1980: The Computation of Equivalent Potential Temperature. Monthly Weather Review, 108, 1046-1053.
Error codes and conditions
Routine |
Message |
Comment |
---|---|---|
get_expected_dew_point |
‘key has to be 1 (upper levels) or 2 (2-meter), got ‘,key |
The input value of key is not allowed. |