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wrf_map

Creates a map background for ARW WRF model data.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"      ; These two libraries are automatically
load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"    ; loaded from NCL V6.4.0 onward.
                                                              ; No need for user to explicitly load.

	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_xy.
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.

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: