easyclimate.field.teleconnection.index_srp

Silk Road pattern (SRP) Index

Functions

calc_index_SRP_EOF1_Yasui_Watanabe_2010(, lon_dim, ...)	The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Yasui and Watanabe (2010):
calc_index_SRP_EOF1_Kosaka_2009(, lon_dim, lat_dim, ...)	The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Kosaka et al. (2009):
calc_index_SRP_EOF1_Chen_Huang_2012(, lon_dim, ...[, ...])	The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Chen and Huang (2009):
calc_index_SRP_EOF1_Sato_Takahashi_2006(, lon_dim, ...)	The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Sato and Takahashi (2006):
calc_index_SRP_1point_Lu_2002(, lon_dim, lat_dim, ...)	The calculation of monthly mean SRP index based on Lu et al. (2002):

Module Contents

easyclimate.field.teleconnection.index_srp.calc_index_SRP_EOF1_Yasui_Watanabe_2010(v200_monthly_data: xarray.DataArray, time_range: slice = slice(None, None), lon_dim: str = 'lon', lat_dim: str = 'lat', lat_range: slice = slice(20, 60), lon_range: slice = slice(0, 150), time_dim: str = 'time', random_state: int | None = None, solver: Literal['auto', 'full', 'randomized'] = 'auto', solver_kwargs: dict = {}, normalized: bool = True) → xarray.DataArray

The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Yasui and Watanabe (2010):

EOF1 of V200 over (\(\mathrm{20 ^{\circ}N - 60 ^{\circ}N; 0 ^{\circ} - 150 ^{\circ}E}\)).

Parameters

v200_monthly_data: xarray.DataArray.

The monthly 200-hPa meridional wind.

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.

lat_range: slice, default: slice(20, 60).

The latitude range of computation using EOFs over the region. The default value is from \(\mathrm{20^{\circ}N}\) to \(\mathrm{60^{\circ}N}\).

lon_range: slice, default: slice(0, 150).

The longitude range of computation using EOFs over the region. The default value is from \(\mathrm{0^{\circ}}\) to \(\mathrm{150^{\circ}E}\).

time_dim: str, default: time.

The time coordinate dimension name.

random_state: int, default None.

Seed for the random number generator.

solver: {“auto”, “full”, “randomized”}, default: “auto”.

Solver to use for the EOFs computation.

solver_kwargs: dict, default {}.

Additional keyword arguments to be passed to the EOFs solver.

Returns

The monthly mean SRP index (xarray.DataArray).

Reference

• Yasui, S., & Watanabe, M. (2010). Forcing Processes of the Summertime Circumglobal Teleconnection Pattern in a Dry AGCM. Journal of Climate, 23(8), 2093-2114.

• Liu Y. Relationship between the Silk Road and Circumglobal Teleconnection Patterns on the Interannual and Interdecadal Timescales. Atmosphere. 2023; 14(11):1626.

See also

get_EOF_model

easyclimate.field.teleconnection.index_srp.calc_index_SRP_EOF1_Kosaka_2009(v200_monthly_data: xarray.DataArray, time_range: slice = slice(None, None), lon_dim: str = 'lon', lat_dim: str = 'lat', lat_range: slice = slice(20, 60), lon_range: slice = slice(30, 130), time_dim: str = 'time', random_state=None, solver: Literal['auto', 'full', 'randomized'] = 'auto', solver_kwargs: dict = {}, normalized: bool = True) → xarray.DataArray

The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Kosaka et al. (2009):

EOF1 of V200 over (\(\mathrm{20 ^{\circ}N - 60 ^{\circ}N; 30 ^{\circ} - 130 ^{\circ}E}\)).

Parameters

v200_monthly_data: xarray.DataArray.

The monthly 200-hPa meridional wind.

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.

lat_range: slice, default: slice(20, 60).

The latitude range of computation using EOFs over the region. The default value is from \(\mathrm{20^{\circ}N}\) to \(\mathrm{60^{\circ}N}\).

lon_range: slice, default: slice(30, 130).

The longitude range of computation using EOFs over the region. The default value is from \(\mathrm{30^{\circ}}\) to \(\mathrm{130^{\circ}E}\).

time_dim: str, default: time.

The time coordinate dimension name.

random_state: int, default None.

Seed for the random number generator.

solver: {“auto”, “full”, “randomized”}, default: “auto”.

Solver to use for the EOFs computation.

solver_kwargs: dict, default {}.

Additional keyword arguments to be passed to the EOFs solver.

normalized: bool, default True, optional.

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

Returns

The monthly mean SRP index (xarray.DataArray).

Reference

• Kosaka, Y., Nakamura, H., Watanabe, M., & Kimoto, M. (2009). Analysis on the dynamics of a wave-like teleconnection pattern along the summertime Asian jet based on a reanalysis dataset and climate model simulations. Journal of the Meteorological Society of Japan. Ser. II, 87(3), 561-580.

• Liu Y. Relationship between the Silk Road and Circumglobal Teleconnection Patterns on the Interannual and Interdecadal Timescales. Atmosphere. 2023; 14(11):1626.

See also

get_EOF_model

easyclimate.field.teleconnection.index_srp.calc_index_SRP_EOF1_Chen_Huang_2012(v200_monthly_data: xarray.DataArray, time_range: slice = slice(None, None), lon_dim: str = 'lon', lat_dim: str = 'lat', lat_range: slice = slice(30, 60), lon_range: slice = slice(30, 130), time_dim: str = 'time', random_state=None, solver: Literal['auto', 'full', 'randomized'] = 'auto', solver_kwargs: dict = {}, normalized: bool = True) → xarray.DataArray

The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Chen and Huang (2009):

EOF1 of V200 over (\(\mathrm{30 ^{\circ}N - 60 ^{\circ}N; 30 ^{\circ} - 130 ^{\circ}E}\)).

Parameters

v200_monthly_data: xarray.DataArray.

The monthly 200-hPa meridional wind.

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.

lat_range: slice, default: slice(20, 60).

The latitude range of computation using EOFs over the region. The default value is from \(\mathrm{30^{\circ}N}\) to \(\mathrm{60^{\circ}N}\).

lon_range: slice, default: slice(30, 130).

The longitude range of computation using EOFs over the region. The default value is from \(\mathrm{30^{\circ}}\) to \(\mathrm{130^{\circ}E}\).

time_dim: str, default: time.

The time coordinate dimension name.

random_state: int, default None.

Seed for the random number generator.

solver: {“auto”, “full”, “randomized”}, default: “auto”.

Solver to use for the EOFs computation.

solver_kwargs: dict, default {}.

Additional keyword arguments to be passed to the EOFs solver.

normalized: bool, default True, optional.

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

Returns

The monthly mean SRP index (xarray.DataArray).

Reference

• Chen, G., & Huang, R. (2012). Excitation Mechanisms of the Teleconnection Patterns Affecting the July Precipitation in Northwest China. Journal of Climate, 25(22), 7834-7851.

• Liu Y. Relationship between the Silk Road and Circumglobal Teleconnection Patterns on the Interannual and Interdecadal Timescales. Atmosphere. 2023; 14(11):1626.

See also

get_EOF_model

easyclimate.field.teleconnection.index_srp.calc_index_SRP_EOF1_Sato_Takahashi_2006(v200_monthly_data: xarray.DataArray, time_range: slice = slice(None, None), lon_dim: str = 'lon', lat_dim: str = 'lat', lat_range: slice = slice(30, 60), lon_range: slice = slice(80, 200), time_dim: str = 'time', random_state=None, solver: Literal['auto', 'full', 'randomized'] = 'auto', solver_kwargs: dict = {}, normalized: bool = True) → xarray.DataArray

The calculation of monthly mean SRP index using empirical orthogonal functions (EOFs) method based on Sato and Takahashi (2006):

EOF1 of V200 over (\(\mathrm{30 ^{\circ}N - 60 ^{\circ}N; 80 ^{\circ}E - 160 ^{\circ}W}\)).

Parameters

v200_monthly_data: xarray.DataArray.

The monthly 200-hPa meridional wind.

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.

lat_range: slice, default: slice(30, 60).

The latitude range of computation using EOFs over the region. The default value is from \(\mathrm{30^{\circ}N}\) to \(\mathrm{60^{\circ}N}\).

lon_range: slice, default: slice(80, 200).

The longitude range of computation using EOFs over the region. The default value is from \(\mathrm{80^{\circ}E}\) to \(\mathrm{160^{\circ}W}\).

time_dim: str, default: time.

The time coordinate dimension name.

random_state: int, default None.

Seed for the random number generator.

solver: {“auto”, “full”, “randomized”}, default: “auto”.

Solver to use for the EOFs computation.

solver_kwargs: dict, default {}.

Additional keyword arguments to be passed to the EOFs solver.

normalized: bool, default True, optional.

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

Returns

The monthly mean SRP index (xarray.DataArray).

Reference

• Chen, G., & Huang, R. (2012). Excitation Mechanisms of the Teleconnection Patterns Affecting the July Precipitation in Northwest China. Journal of Climate, 25(22), 7834-7851.

• Liu Y. Relationship between the Silk Road and Circumglobal Teleconnection Patterns on the Interannual and Interdecadal Timescales. Atmosphere. 2023; 14(11):1626.

See also

get_EOF_model

easyclimate.field.teleconnection.index_srp.calc_index_SRP_1point_Lu_2002(v200_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 SRP index based on Lu et al. (2002):

V200 at \(\mathrm{42.5 ^{\circ}N, 105 ^{\circ}E}\).

Parameters

v200_monthly_data: xarray.DataArray.

The monthly 200-hPa meridional wind.

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 SRP index (xarray.DataArray).

Reference

• Lu, R.-Y., Oh, J.-H., & Kim, B.-J. (2002). A teleconnection pattern in upper-level meridional wind over the North African and Eurasian continent in summer. Tellus A: Dynamic Meteorology and Oceanography, 54(1), 44-55.

• Liu Y. Relationship between the Silk Road and Circumglobal Teleconnection Patterns on the Interannual and Interdecadal Timescales. Atmosphere. 2023; 14(11):1626.