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The Spectra Editor
Data
Drop any icon containing or returning BUFR data. This may be, for example, a MARS Retrieval (of observations) icon, a BUFR file icon or an Observation Filter icon (provided it outputs BUFR, not geopoints).
Output
Specifies the output format you want. Specify one of the geopoints formats (Geographical Points, Geographical Polar Vectors or Geographical X Y Vectors).
Parameter
To specify a parameter enter its unique BUFR descriptor value (a numerical code). Geographical Polar Vectors and Geographical X Y Vectors require two descriptors, separated by a slash (/). The descriptor value is of the form XXYYY, where XX defines the class (e.g. 12 = Temperature class) and YYY the parameter within that class (e.g. 12004 = Dry bulb Temperature at 2m). These descriptor values are different from the ones of the GRIB format. If you do not know the descriptor value, click-left on the assist button to obtain a check list of parameters and associated descriptors. This list only contains the most common parameters. If the one you need is not on the list you can use the BUFR Examiner (right-click, Examine the BUFR file) to see what is there, or up its descriptor value in the "BUFR Reference Manual" (available from http://www.ecmwf.int/products/data/software/bufr.html#description) - see "BUFR Table B", pages 6-19. The significance of code and flag values for non-quantitative parameters are given in the same manual, in "BUFR code table", pages 22-70.
Missing Data
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The Spectra editor belongs to a type of editor known as family editor which allows related sets of input specifications to be grouped in the same icon editor, each in its own tabbed pane. The available working input panes are :
Spec Graph - To plot a graph of log/linear amplitude against log/linear n, where n is the Legendre polynomial order
Spec Contour (not available yet) - To plot a map contour plot of amplitude against wave number and forecast length
To operate with this icon first you need to select which output you want to produce by clicking the tab of the corresponding pane. Each input pane contains a different set of parameters, with some in common.
Data
Specifies the data required for the application. The assist button provides a tailor made MARS request in case you need some guidance in the data specification.
Diurnal Cycle
Specifies whether to subtract the diurnal cycle. Yes to subtract, No otherwise.
Truncation
Specifies the highest wave number in spectra plots.
Smoothing
Specifies whether to smooth the plot curve(s). Yes to smooth, No otherwise.
Tension
Specifies the smoothing interpolation. Only Spline is currently available.
Nl24int
Specifies whether to plot values only every 24 hours. Yes for only every 24 hours, No otherwise.
Hilorad
Specifies the search radius for plotting of high/low markers.