improver.cli.orographic_enhancement module

Script to calculate orographic enhancement.

extract_and_check(cube, height_value, units)[source]

Function to attempt to extract a height level. If no matching level is available an error is raised.

Parameters:

  • cube (cube) – Cube to be extracted from and checked it worked.

  • height_value (float) – The boundary height to be extracted with the input units.

  • units (str) – The units of the height level to be extracted.

Returns:

A cube containing the extracted height level.

Return type:

iris.cube.Cube

Raises:

ValueError – If height level is not found in the input cube.

process(temperature, humidity, pressure, wind_speed, wind_direction, orography, *, boundary_height=1000.0, boundary_height_units='m')[source]

Calculate orographic enhancement

Uses the ResolveWindComponents() and OrographicEnhancement() plugins. Outputs data on the high resolution orography grid.

Parameters:

  • temperature (iris.cube.Cube) – Cube containing temperature at top of boundary layer.

  • humidity (iris.cube.Cube) – Cube containing relative humidity at top of boundary layer.

  • pressure (iris.cube.Cube) – Cube containing pressure at top of boundary layer.

  • wind_speed (iris.cube.Cube) – Cube containing wind speed values.

  • wind_direction (iris.cube.Cube) – Cube containing wind direction values relative to true north.

  • orography (iris.cube.Cube) – Cube containing height of orography above sea level on high resolution (1 km) UKPP domain grid.

  • boundary_height (float) – Model height level to extract variables for calculating orographic enhancement, as proxy for the boundary layer.

  • boundary_height_units (str) – Units of the boundary height specified for extracting model levels.

Returns:

Precipitation enhancement due to orography on the high resolution input orography grid.

Return type:

iris.cube.Cube