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wrf_omega

Calculates approximate omega in C, given vertical velocity, water vapor mixing ratio, temperature, and pressure from WRF model output.

Available in version 6.2.0 and later.

Prototype

	function wrf_omega (
		qv  : numeric,  
		t   : numeric,  
		v   : numeric,  
		p   : numeric   
	)

	return_val  :  float or double

Arguments

qv

Water vapor mixing ratio in [kg/kg]. The rightmost dimensions are bottom_top x south_north x west_east.

t

Temperature in [K]. An array with the same dimensionality as qv.

v

Vertical velocity in [m/s]. An array with the same dimensionality as qv.

p

Pressure in [mb]. An array with the same dimensionality as qv.

Return value

Approximate omega [dp/dt]. The rightmost three dimensions will be bottom_top x south_north x west_east, and the leftmost dimensions, if any, will be the same as qv's. The array will contain the same named dimensions as qv; otherwise, the rightmost two dimensions will be named "south_north" and "west_east". The type will be double if any of the input is double, and float otherwise.

Description

This function calculates approximate omega in C, given vertical velocity, water vapor mixing ratio, temperature, and pressure from WRF model output.

You can use wrf_user_getvar with an argument of "omg" to calculate this diagnostic.

The return variable will contain two attributes:

return_val@description = "Omega"
return_val@units = "Pa/s"

See Also

wrf_virtual_temp, wrf_wetbulb, wrf_user_getvar

See the full list of WRF functions.

Examples

Note: for WRF variable names and their definitions, you can easily check them by using "ncl_filedump": 

  ncl_filedump wrfout_d01_2000-01-24_12:00:00.nc

Example 1



You can see some other example scripts and their resultant images at:



http://www2.mmm.ucar.edu/wrf/OnLineTutorial/Graphics/NCL/