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Driver to calculate and plot seasonal spectra via segment averaging as defined by the US-CLIVAR MJO diagnostics website.

Available in version 5.1.0 and later.


load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"      ; These three libraries are automatically
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"       ; loaded from NCL V6.2.0 onward.
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"   ; No need for user to explicitly load.
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/diagnostics_cam.ncl"

	procedure mjo_spectra (
		x    [*][*][*] : numeric,  
		date       [*] : integer,  
		wy         [*] : numeric,  
		latS       [*] : numeric,  
		latN       [*] : numeric,  
		lonL       [*] : numeric,  
		lonR       [*] : numeric,  
		nameRegion [*] : string,   
		opt        [1] : logical   




A three-dimensional variable array. Nominally: (time,lat,lon).


An integer array containing the date as "YYYYMMDD".


A one-dimensional array containing the latitudinal weights associated with x.


Southern latitude of boundary of region. The US-CLIVAR MJO diagnostics website specifies the boundaries of predefined regions. See Table 1.


Northern latitude of boundary of region.


Left longitude of boundary of region.


Right longitude of boundary of region.


Name of region outlined by the latS, latN, lonL, lonR. This can be any name but the US-CLIVAR MJO diagnostics website specifies a few: "IO" (Indian Ocean), "WP" (Western Pacific), etc. See Table 1.


If opt=False, the function will operate under default mode regardless of any attributes associated with the variable.

If opt=True, then the following attributes, associated with opt, may be used to alter the default behavior.

opt@logXAxis=: If True, a log frequency or period axis will be created; if False a linear frequency or period axis will be used. Default: opt@logXAxis=True.

opt@periodXAxis: If True, period will be plotted; if False, frequency will be plotted. Default: opt@periodXAxis=True

opt@pltDir: This specifies the directory to which the output figure(s) will be sent. Default: opt@pltDir="./" (current directory).

opt@pltType: This may be set to "x11", "ps", "eps", "pdf" or "png". If "png", a temporary eps file will be created and the ImageMagick convert tool will be used to convert to "png". The temporary eps file will be deleted. Default: opt@pltType="eps"

opt@pltConvert: Options for ImageMagick convert tool. Default: no options are specified.


This implements the specifications of MJO CLIVAR for segment averaging. It is a driver to the mjo_spectra_segment function. It creates a graphic for each region specified by nameRegion.

See Also

mjo_spectra_segment, band_pass_area_time,
band_pass_area_time_plot, band_pass_latlon_time,
band_pass_hovmueller, band_pass_hovmueller_plot,
filwgts_lanczos, wgt_areaave, wgt_areaave_Wrap,
wkSpaceTime, wkSpaceTime_cam


See Example 7 of the Madden-Julian Oscillation web page.