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clmMonLLT

Calculates long term monthly means (monthly climatology) from monthly data (lat,lon,time version)

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.2.0 onward.
                                                             ; No need for user to explicitly load.

	function clmMonLLT (
		x [*][*][*] : numeric   
	)

	return_val [*][*][12] :  numeric

Arguments

x

A three-dimensional array of any numeric type. Dimensions must be lat, lon, time. The time dimension must be a multiple of 12. The dimensions must be named.

Return value

An array of the same size and type as x except that the rightmost dimension will be of size 12.

Description

Calculate long term monthly means (monthly climatology) from monthly data.

See Also

clmMonLLLT, clmMonTLL, clmMonTLLL, calcMonAnomLLLT, calcMonAnomLLT, calcMonAnomTLL, calcMonAnomTLLL

Examples

The following require that contributed.ncl be loaded prior to invoking the function.

       load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

Example 1

Calculate the monthly climatology of u(lev,lat,lon,time) where

[lat | 128] x [lon | 256] x [time | 528] 
This represent 44 years [44*12=528] of monthly data. Consider the following code snippet:
      f    = addfile("x.1958-2001.nc, "r")
      t    = f->T2m
      tClm = clmMonLLT( t )
      printVarSummary(tClm) 
The result is:
variable: tClm
Type: float
Total Size: 36175872 bytes
            9043968 values
Number of Dimensions: 3
Dimensions and sizes:  [lat | 128] x [lon | 256] x [month | 12]  
Coordinates: 
            lat: [-88.92773..88.92773]
            lon: [ 0..358.53]
            month: [0..11]
Number Of Attributes: 7
  time_op_ncl : Climatology: 44 years
  cell_method : time: mean
  standard_name :       eastward_wind
  units :       m/s
  long_name :   U velocity
  _FillValue :  -999