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The Thermo Data Editor
The Tephigram Thermo Data 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 (like the Simple Formula icon - see Figure III-3 on page III-71). The available working input panes are:
Pm Bufr Tephi Thermo - Provides provides input for tephigrams thermodynamic diagrams based on observation (BUFR) data.
Pm Grib Tephi Thermo - Provides provides input for tephigrams thermodynamic diagrams based on model field (GRIB) data post 4th April 1995
Pm Pre19950404Grib Tephi - Provides input for tephigrams based on model field (GRIB) data pre 4th April 1995
The two varieties of GRIB data tephigrams exist due to changes in the attributes of the input data - parameter Q changed to Gaussian Grid from Spherical Harmonics.
To operate with this icon first you need to select which output you want to produce select one of the above options by clicking the tab of the corresponding pane.
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
If set to Ignore, missing data is not included in the output file; this is the default behaviour. If set to Include, missing data will be output to the geopoints file, its value being set to that specified by Missing Data Value. Note that when the output format is one of the two geopoints vector formats, the observation is considered missing if one or both of the parameters are missing.
appropriate menu option from the Data_Type parameter.
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Specifies the data to be used in the plotting of a thermodynamic diagram from observations data. The icon field assist button provides a tailor made MARS request to help with the data specification. The data should be upper air sounding data (VSNS - Vertical Sounding Non-Satellite ). Please note that PILOT observations (winds only) do not have enough data for plotting a thermodynamic diagram.
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Specifies the data to be used in the plotting of a thermodynamic diagram from model field data. The icon field assist button provides a tailor made MARS request to help with the data specification. The data should include gridded model fields of Temperature and Specific Humidity. These parameters must have the same number of levels and they will be used to compute the Dew Point parameter. Fieldsets U and V wind components are optional, but if given they will be used to compute the wind vectors data unit. These two components must have the same number of levels, but not necessarily have the same number of levels of Temperature and Specific Humidity. If the data is given in model levels then a Logarithm of Surface Pressure field must be provided too. The data can be provided as a single GRIB file or as multiple GRIB files.
Point Selection
Specifies how the geographical location, for which the diagram is to be plotted, will be selected. Options are: Coordinates, Area Average and Station.
Coordinates
Specifies the geographical location for which the diagram is to be plotted. Enter the coordinates (lat/long) of a point separated by a "/" (lat/long). Alternatively, use the coordinate assist button.
Area Average
Specifies a geographical area over which an area average value will be used, instead of a point value, to produce the diagram. Enter the coordinates (lat/long) of an area separated by a "/" (top left lat and long, bottom right lat and long). Alternatively, use the coordinate assist button.
Station
Specifies the location for which the diagram is to be plotted. In the Bufr Thermo dialogue, this must define a meteorological station that provides full upper air soundings. In the Grib Thermo dialogue, this may represent any arbitrary geographical point.
Point Extraction
Specifies the way to calculate values at the point location for GRIB thermodynamic diagrams. Options are:
Interpolate - interpolate values from the surrounding grid points (default)
Nearest Gridpoint - using the data of the nearest grid point
Dew Point Formulation
Specifies the equation to compute the Dew Point parameter. Options are: Saturation Over Water and Mixed Phase 0 to -23.
Temperature Param
Specifies the parameter number of the temperature, if the data is a non-ECMWF. ECMWF uses specific parameter numbers different from the WMO ones.
Specific Humidity Param
Specifies the parameter number of the specific humidity, if the data is a non-ECMWF. ECMWF uses specific parameter numbers different from the WMO ones.
Lnsp Param
Specifies the parameter number of the Lnsp, if the data is a non-ECMWF. ECMWF uses specific parameter numbers different from the WMO ones.
U Wind Param
Specifies the parameter number of the U wind component, if the data is a non-ECMWF. ECMWF uses specific parameter numbers different from the WMO ones.
V Wind Param
Specifies the parameter number of the V wind component, if the data is a non-ECMWF. ECMWF uses specific parameter numbers different from the WMO ones.