Identification

Title

Impact of the Polar Vortex on Sub-Seasonal O/N 2 Variability in the Lower Thermosphere Using GOLD and WACCM-X

Abstract

We provide observational evidence that the stability of the stratospheric Polar vortex (PV) is a significant driver of sub-seasonal variability in the thermosphere during geomagnetically quiet times when the PV is anomalously strong or weak. We find strong positive correlations between the Northern Annular Mode (NAM) index and subseasonal (10-90 days) Global Observations of the Limb and Disk (GOLD) O/N-2 perturbations at low to mid-northern latitudes, with a largest value of +0.55 at similar to 30.0 degrees N when anomalously strong or weak (NAM >2.5 or < -2.1) vortex times are considered. Strong agreement for O/N-2 variability and O/N-2-NAM correlations is found between GOLD observations and the Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (WACCM-X) simulations, which is then used to delineate the global distribution of O/N-2-NAM correlations. We find negative correlations between subseasonal variability in WACCM-X O/N-2 and NAM at high northern and southern latitudes (as large as -0.54 at similar to 60.0 degrees S during anomalous vortex times). These correlations suggest that PV driven upwelling at low latitudes is accompanied by corresponding downwelling at high latitudes in the lower thermosphere (similar to 80-120 km), which is confirmed using calculations of residual mean meridional circulation from WACCM-X.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7db8635

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

2024-06-21T00:00:00Z

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