easyclimate.field.teleconnection.index_eu

The Eurasian pattern (EU) pattern

Functions

calc_index_EU_Wallace_Gutzler_1981(, lon_dim, lat_dim, ...)

The calculation of monthly mean Eurasian pattern (EU) index using Pointwise method following Wallace and Gutzler (1981):

Module Contents

easyclimate.field.teleconnection.index_eu.calc_index_EU_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 Eurasian pattern (EU) index using Pointwise method following Wallace and Gutzler (1981):

\[\mathrm{EU = - \frac{1}{4} Z^*(55^{\circ}N, 20^{\circ}E) + \frac{1}{2} Z^*(55^{\circ}N, 75^{\circ}E) - \frac{1}{4} Z^*(40^{\circ}N, 145^{\circ}E)}\]

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.

normalized: bool, default True, optional.

Whether to standardize the index based on standard deviation over time_range.

Returns

The monthly mean EU index (xarray.DataArray).

Reference