Identification

Title

The comparative importance of DE3, SE2, and SPW4 on the generation of wavenumber-4 longitude structures in the low-latitude ionosphere during September equinox

Abstract

Numerical simulations are performed to investigate the generation of the wave-4 longitude variation in the low-latitude ionosphere due to the diurnal eastward propagating nonmigrating tide with zonal wavenumber 3 (DE3), semidiurnal eastward propagating nonmigrating tide with zonal wavenumber 2 (SE2), and stationary planetary wave 4 (SPW4). From a fixed local time perspective, the DE3, SE2, and SPW4 all appear as wave-4 structures in longitude, and thus each of these waves must be considered as a potential source of the wave-4 variation in the ionosphere. Both the DE3 and SPW4 are found to produce significant wave-4 variations in the equatorial vertical E × B drift velocity, and in the ionospheric peak density (NmF2) at 15°N magnetic latitude. The daytime wave-4 variation in NmF2 is driven by the combination of vertical E × B drift variability and in-situ effects due largely to meridional neutral winds. The simulation results indicate that the SE2 is not a contributor to the wave-4 longitude variation. Our results further demonstrate that the actual wave-4 longitude variation is due to a combination of the DE3 and SPW4. We therefore conclude that, in addition to the DE3, the SPW4 also needs to be considered as an important driver of the wave-4 longitude variation in the low-latitude ionosphere. We additionally present evidence for the generation of the SPW4 due to the nonlinear interaction between the migrating diurnal tide and the DE3, and demonstrate the impact of DE3 variability on the amplitude of the SPW4.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7np257w

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

2012-10-13T00:00:00Z

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Conformity

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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