Identification

Title

The role of downward plasma diffusion in the ionospheric nighttime Weddell Sea Anomaly

Abstract

This study investigates the role of downward plasma diffusion in the ionospheric nighttime Weddell Sea Anomaly (WSA), characterized by an anomalous diurnal electron density peak in nighttime from the South Pacific to South America. Traditionally attributed to prolonged photoionization and ionospheric uplift during summer, the WSA is not reproduced by the latest Thermosphere Ionosphere Electrodynamics General Circulation Model. We introduce a data‐driven flux approach to incorporate more realistic diffusive flux, significantly improving the model's ability to replicate key WSA features. Simulations show that topside plasma diffusion turns downward in the evening, peaking near midnight, contributing notably to the NmF2 enhancement. Around 22:00 local time, downward plasmaspheric diffusion becomes the dominant plasma source, rivaling or exceeding local photoionization (12.08 vs. 8.50  at 22:30). These results offer new insight into the interplay of processes driving the WSA and underscore the importance of plasma diffusion in ionospheric dynamics.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.net/ark:/85065/d7gx4h0h

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

2025-06-16T00:00:00Z

Frequency of update

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Conformity

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Use constraints

<span style="font-family:Arial;font-size:10pt;font-style:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span>

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