Calculates the rotation of a vector field

Energy-Vorticity theory (EVT) is the fundamental theory to describe processes in the atmosphere by combining conserved quantities from hydrodynamics and thermodynamics. The package 'meteoEVT' provides functions to calculate many energetic and vortical quantities, like potential vorticity, Bernoulli function and dynamic state index (DSI) [e.g. Weber and Nevir, 2008, <doi:10.1111/j.1600-0870.2007.00272.x>], for given gridded data, like ERA5 reanalyses. These quantities can be studied directly or can be used for many applications in meteorology, e.g., the objective identification of atmospheric fronts. For this purpose, separate function are provided that allow the detection of fronts based on the thermic front parameter [Hewson, 1998, <doi:10.1017/S1350482798000553>], the F diagnostic [Parfitt et al., 2017, <doi:10.1002/2017GL073662>] and the DSI [Mack et al., 2022, <arXiv:2208.11438>].

Laura Mack

meteoEVT

Computation and Visualization of Energetic and Vortical
Atmospheric Quantities

rot function

<dl><dt>fld</dt>
<dd>with dimensions (lon,lat,p,d)</dd>
<dt>lat</dt>
<dd>vector containing latitude</dd>
<dt>d</dt>
<dd>scalar for dimension (use d=2 for horizontal gradient and d=3 for 3d-gradient)</dd>
<dt>system</dt>
<dd>for type of coordinate system (use 'p' for pressure system and 'z' for height system)</dd>
<dt>rho</dt>
<dd>field with dimensions (lon,lat,p) for density or a scalar rho (for constant density)</dd>
<dt>dx</dt>
<dd>x resolution in the corresponding unit (e.g. 0.25 degree for ERA5 with <code>mode='lonlat'</code> or e.g. 1000 m in cartesian coordinates with <code>mode='cartesian'</code>)</dd>
<dt>dy</dt>
<dd>y resolution in the corresponding unit (e.g. 0.25 degree for ERA5 with <code>mode='lonlat'</code> or e.g. 1000 m in cartesian coordinates with <code>mode='cartesian'</code>)</dd>
<dt>plev</dt>
<dd>a scalar containing the p resolution (if equidistant) or a vector containing pressure levels in Pa (for non-equidistant)</dd>
<dt>mode</dt>
<dd>the coordinate system, options are lonlat for a longitude-latitude-grid (default), or cartesian for an equidistant cartesian grid</dd></dl>

Arguments

rotation — rot

<dl>

<dt>fld</dt>
<dd>with dimensions (lon,lat,p,d)</dd>


<dt>lat</dt>
<dd>vector containing latitude</dd>


<dt>d</dt>
<dd>scalar for dimension (use d=2 for horizontal gradient and d=3 for 3d-gradient)</dd>


<dt>system</dt>
<dd>for type of coordinate system (use 'p' for pressure system and 'z' for height system)</dd>


<dt>rho</dt>
<dd>field with dimensions (lon,lat,p) for density or a scalar rho (for constant density)</dd>


<dt>dx</dt>
<dd>x resolution in the corresponding unit (e.g. 0.25 degree for ERA5 with <code>mode='lonlat'</code> or e.g. 1000 m in cartesian coordinates with <code>mode='cartesian'</code>)</dd>


<dt>dy</dt>
<dd>y resolution in the corresponding unit (e.g. 0.25 degree for ERA5 with <code>mode='lonlat'</code> or e.g. 1000 m in cartesian coordinates with <code>mode='cartesian'</code>)</dd>


<dt>plev</dt>
<dd>a scalar containing the p resolution (if equidistant) or a vector containing pressure levels in Pa (for non-equidistant)</dd>


<dt>mode</dt>
<dd>the coordinate system, options are lonlat for a longitude-latitude-grid (default), or cartesian for an equidistant cartesian grid</dd>

</dl>

rot: rotation

Description

Usage

Value

Arguments