mhovmoeller_area

../../_images/MHOVMOELLERDATA.png

Generates a Hovmoeller diagram data unit for a given geographical area for GRIB (Fieldset) input. The generated data can be used to display a two-dimensional graph with latitude or longitude as one axis and time as the other. The average values for each field are taken along the North-South or East-West direction.

The resulting data can be plotted (using a default visualisation and with the plot area based on the range of data values) or saved as a NetCDF data file using write().

If access to the computed values is not required, or for more control of the plotting, use mhovmoellerview().

Note

See also mhovmoeller_line(), mhovmoeller_vertical() and mhovmoeller_expand().

Note

This function performs the same task as the Hovmoeller Data icon in Metview’s user interface. It accepts its parameters as keyword arguments, described below.

mhovmoeller_area(**kwargs)

Provides input for Hovmoeller diagrams derived from a geographical area.

Parameters

  • data (Fieldset) – Specifies the GRIB data (Fieldset) from which to derive the Hovmeller diagram. data must specify a time-series of one meteorological variable on a given level on a latitude-longitude or Gaussian grid. Multiple parameters/levels are not supported.

  • area (list[number], default: [30, -30, -30, 30]) – Specifies the coordinates of the area (as [north, west, south, east]) over which the Hovmoeller diagram is calculated.

  • area_statistics ({"mean", "minimum", "maximum", "stdev", "variance", "median"}, default: "mean") – Specifies the type of computation performed along the average_direction`. For “mean”, “stdev” or “variance” when average_direction is “north_south” the aggregation is weighted by the cosine of the latitudes. New in Metview version 5.18.0

  • average_direction ({"east_west", "north_south"}, default: "east_west") – Specifies the direction along which the computation defined in area_statistics is performed. When it is “north_south” and area_statistics is “average”, “stdev” or “variance” the aggregation is weighted by the cosine of the latitudes.

  • swap_axes ({"no", "yes"}, default: "no") – By default, the definition of the vertical and horizontal axes of the Hovmoeller diagrams follows pre-defined rules. However, if swap_axes is set to “yes” then the axes will be swapped around.

  • resolution (number, default: 1.0) – Used to interpolate the data onto a regular grid, and applies to both the horizontal and vertical axes where appropriate. This parameter is essential for creating a Hovmoeller diagram from satellite data.

Return type

NetCDF