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Merges a multiple level variable with the corresponding surface variable.

Available in version 5.2.0 and later.


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 merge_levels_sfc (
		x       : numeric      ,  
		xsfc    : numeric   ,     
		opt [1] : integer         



An array of any the following shapes: x(lev), x(time,lev), x(lev,lat,lon), x(time,lev,lat,lon) or x(case,time,lev,lat,lon). It is required that the dimensions be named.


An array of the one less rank than x. The shapes corresponding to the argument x: xsfc[1], xsfc(time), xsfc(lat,lon), xsfc(time,lat,lon) or xsfc(case,time,lat,lon). It is required that the dimensions be named.


An integer:
opt greater than or equal to zero if x is top-to-bottom ordering.
opt less than zero if x is bottom-to-top ordering.

Return value

A multi-dimensional array of the same rank as x but with one additional level.


Commonly, models and reanalysis datasets provide variable with multiple levels, say, x(time,lev,lat,lon) and a separate corresponding surface variable xsfc(time,lat,lon). In some applications, it may be useful to merge these into one variable. See the Example

See Also

array_append_record, table_attach_columns, table_attach_rows


Example 1

Consider x(ntim,klev,nlat,mlon) and xsfc(ntim,nlat,mlon) where "x" is ordered bottom-to-top.

      xNew = merge_levels_sfc(x, xsfc, -1)    ; xNew(ntim,klev+1,nlat,mlon)
Example 2

See Example 4 at hydro. This illustrates one use of the merge_levels_sfc function.