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


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 clmMonTLL (
		x [*][*][*] : float or double   

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



A three-dimensional array of type float or numeric. Dimensions must be time, lat, lon. 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 leftmost dimension will be of size 12.


Calculate long term monthly means (monthly climatology) from monthly data. The "temporal" dimension will be of size 12 and will be named "month".

See Also

clmMonLLLT, clmMonLLT, clmMonTLLL, calcMonAnomLLLT, calcMonAnomLLT, calcMonAnomTLL, calcMonAnomTLLL


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 T2m(time,lat,lon) where

[time | 528] x [lat | 128] x [lon | 256] 
This represent 44 years [44*12=528] of monthly data. Consider the following code snippet:
      f    = addfile(", "r")
      t    = f->T2m
      tClm = clmMonTLL( t )
The result is:
variable: tClm
Type: float
Total Size: 36175872 bytes
            9043968 values
Number of Dimensions: 3
Dimensions and sizes:   [month | 12] x [lat | 128] x [lon | 256]
            month: [0..11]
            lat: [-88.92773..88.92773]
            lon: [ 0..358.53]
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