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wrf_vector

Creates a vector plot from ARW WRF model output.

Available in version 4.3.1 or later.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"

	function wrf_vector (
		nc_file       : file,     
		wks           : graphic,  
		data_u [*][*] : numeric,  
		data_v [*][*] : numeric,  
		res           : logical   
	)

	return_val [1] :  graphic

Arguments

nc_file

Input netCDF file name.

wks

An NCL Workstation identifier. The identifier is one returned either from calling gsn_open_wks or calling create to create a Workstation object.

data_u

A two-dimensional array of the U component of the wind.

data_v

A two-dimensional array of the V component of the wind.

res

A variable containing an optional list of plot resources, attached as attributes.

Return value

A scalar id of the plot created is returned.

Description

This function creates a vector plot.

If data has a _FillValue attribute, this value will be used as a missing value.

If data has a "description" attribute, this value will be used in the plot title.

wrf_vector is part of a library of functions and procedures in WRFUserARW.ncl written to help users plot ARW WRF model data.

WRF-related questions should be sent to wrfhelp@ucar.edu.

See Also

wrf_contour, wrf_map_overlays, wrf_overlays, wrf_map

Examples

Example 1

  load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
  load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"

  a = addfile("wrfout_d01_2000-01-24_12:00:00.nc","r")

  wks = gsn_open_wks("x11","test")

  u10 = wrf_user_getvar(a,"U10",0)   ; U component of the wind at 10m
  v10 = wrf_user_getvar(a,"V10",0)   ; V component of the wind at 10m

  res = True
  vector = wrf_vector(a,wks,u10,v10,res)

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

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