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wrf_map

Creates a map background for ARW WRF model data.

Prototype

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

	function wrf_map (
		wks      : graphic,  
		nc_file  : file,     
		res      : logical   
	)

	return_val [1] :  graphic

Arguments

wks

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

nc_file

Reference to an input netCDF file opened with addfile.

res

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

Return value

A scalar id of the map created is returned.

Description

This function creates a map background for any ARW WRF projection.

You can use the res variable to set some optional attributes for customizing the map:

  • ZoomIn - default is False

    If this resource is set to True, then this indicates you want to zoom in on the map. You need to further set these special attributes:

    • Ystart,Xstart - default is (0,0)

      Set this pair to the index values in the 2-dimensional latitude/longitude arrays that represents the minimum latitude/longitude value you want to zoom in on.

    • Yend,Xend - default is (nlat-1,nlon-1) Set this pair to the index values in the 2-dimensional latitude/longitude arrays that represents the maximum latitude/longitude value you want to zoom in on.

    The above four index values can be calculated using wrf_user_ll_to_ij.

    Here's an example of using these resources.

wrf_map 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_map_overlays, wrf_contour, wrf_vector, wrf_user_ll_to_ij, wrf_map_resources

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")

  map = wrf_map(wks,a,True)
You can see some other example scripts and their resultant images at:
http://www.mmm.ucar.edu/wrf/OnLineTutorial/Graphics/NCL/