easyclimate.field.teleconnection.index_ea

The eastern Atlantic (EA) pattern

Functions

calc_index_EA_Wallace_Gutzler_1981(, lon_dim, lat_dim, ...)

The calculation of monthly mean eastern Atlantic (EA) index using Pointwise method following Wallace and Gutzler (1981):

Module Contents

easyclimate.field.teleconnection.index_ea.calc_index_EA_Wallace_Gutzler_1981(z_monthly_data: xarray.DataArray, time_range: slice = slice(None, None), lon_dim: str = 'lon', lat_dim: str = 'lat', time_dim: str = 'time', normalized: bool = True) → xarray.DataArray

The calculation of monthly mean eastern Atlantic (EA) index using Pointwise method following Wallace and Gutzler (1981):

\[\mathrm{EA = \frac{1}{2} Z^*(55^{\circ}N, 20^{\circ}W) - \frac{1}{4} Z^*(25^{\circ}N, 25^{\circ}W) - \frac{1}{4} Z^*(50^{\circ}N, 40^{\circ}E)}\]

where \(Z^*\) denotes monthly mean 500 hPa height anomaly.

Parameters

z_monthly_data: xarray.DataArray.

The monthly geopotential height. The 500hPa layer is recommended.

time_range: slice, default: slice(None, None).

The time range of seasonal cycle means to be calculated. The default value is the entire time range.

lon_dim: str, default: lon.

Longitude coordinate dimension name. By default extracting is applied over the lon dimension.

lat_dim: str, default: lat.

Latitude coordinate dimension name. By default extracting is applied over the lat dimension.

time_dim: str, default: time.

The time coordinate dimension name.

Returns

The monthly mean EA index (xarray.DataArray).

Reference