Identification

Title

Seasonal sensitivity of the northern hemisphere jet streams to Arctic temperatures on subseasonal time scales

Abstract

Near-surface Arctic warming has been shown to impact the midlatitude jet streams through the use of carefully designed model simulations with and without Arctic sea ice loss. In this work, a Granger causality regression approach is taken to quantify the response of the zonal wind to variability of near-surface Arctic temperatures on subseasonal time scales across the CMIP5 models. Using this technique, a robust influence of regional Arctic warming on the North Atlantic and North Pacific jet stream positions, speeds, and zonal winds is demonstrated. However, Arctic temperatures only explain an additional 3%-5% of the variance of the winds after accounting for the variance associated with the persistence of the wind anomalies from previous weeks. In terms of the jet stream response, the North Pacific and North Atlantic jet streams consistently shift equatorward in response to Arctic warming but also strengthen, rather than weaken, during most months of the year. Furthermore, the sensitivity of the jet stream position and strength to Arctic warming is shown to be a strong function of season. Specifically, in both ocean basins, the jets shift farthest equatorward in the summer months. It is argued that this seasonal sensitivity is due to the Arctic-warming-induced wind anomalies remaining relatively fixed in latitude, while the climatological jet migrates in and out of the anomalies throughout the annual cycle. Based on these results, model differences in the climatological jet stream position are shown to lead to differences in the jet stream position's sensitivity to Arctic warming.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d76q20wn

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2017-12-01T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact