Identification

Title

The effects of IMF By on the middle thermosphere during a geomagnetically "quiet" period at solar minimum

Abstract

Numerical simulations using the National Center for Atmospheric Research (NCAR) thermosphere-ionosphere-electrodynamics general circulation model (TIE-GCM) are performed to elucidate the effects of the interplanetary magnetic field (IMF) on the middle thermosphere composition during a "geomagnetically quiet" period from the day of year (DOY) 110-111 in 2019 (when the Auroral electrojet (AE) index never exceeded 300 nT and the Kp never exceeded 2). In particular, this paper aims to examine how the Global-scale Observations of the Limb and Disk (GOLD) mission observed daytime thermospheric O and N-2 column density ratio (Sigma O/N-2) depletion at mid-latitudes originated under such a "geomagnetically quiet" condition. A comparison of electric potential, Joule heating rate per unit mass, ion velocity, neutral temperature and winds in the middle thermosphere (similar to 160 km) between real IMF and without the IMF east-west component (B-y) indicates that a B-y dominant condition can enhance their strengths under this "geomagnetically quiet" condition. Consequently, Sigma O/N-2 depletion with a stronger magnitude (30% compared with similar to 8% without B-y) and larger disturbed area was introduced in the post-midnight sector at high-latitudes due to strong and localized upwelling associated with the enhanced Joule heating rate per unit mass. The Sigma O/N-2 depletion was transported equatorward and corotated from local post-midnight to early morning, and was observed by GOLD at middle latitudes during daytime.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7mk6hkp

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

2022-05-01T00:00:00Z

Frequency of update

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Use constraints

Copyright 2022 American Geophysical Union.

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

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 date

2025-07-11T16:03:47.354463

Metadata language

eng; USA