Identification

Title

Explaining solar flare-induced ionospheric ion upflow at Millstone Hill (42.6°n)

Abstract

Previous studies have shown that solar flares can significantly affect Earth's ionosphere and induce ion upflow with a magnitude of similar to 110 m/s in the topside ionosphere (similar to 570 km) at Millstone Hill (42.61 degrees N, 71.48 degrees W). We use simulations from the Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIEGCM) and observations from Incoherent Scatter Radar (ISR) at Millstone Hill to reveal the mechanism of ionospheric ion upflow near the X9.3 flare peak (07:16 LT) on 6 September 2017. The ISR observed ionospheric upflow was captured by the TIEGCM in both magnitude and morphology. The term analysis of the F-region ion continuity equation during the solar flare shows that the ambipolar diffusion enhancement is the main driver for the upflow in the topside ionosphere, while ion drifts caused by electric fields and neutral winds play a secondary role. Further decomposition of the ambipolar diffusive velocity illustrates that flare-induced changes in the vertical plasma density gradient is responsible for ion upflow. The changes in the vertical plasma density gradient are mainly due to solar extreme ultraviolet (EUV, 15.5-79.8 nm) induced electron density and temperature enhancements at the F-2-region ionosphere with a minor and indirectly contribution from X-ray (0-15.5 nm) and ultraviolet (UV, 79.8-102.7 nm).

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7ng4vfj

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

2022-07-13T00:00:00Z

Frequency of update

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Conformity

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Constraints related to access and use

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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

2023-08-18T18:18:07.274994

Metadata language

eng; USA