Identification

Title

Artificial plasma cave in the low-latitude ionosphere results from the radio occultation inversion of the FORMOSAT-3/COSMIC

Abstract

Previous studies report unexpected electron density reductions, termed "plasma caves," located underneath the equatorial ionization anomaly (EIA) crests. A radio occultation (RO) observation simulation experiment has been built to evaluate possible biases introduced by the spherical symmetry assumption in the standard (Abel) RO inversion processes. The experiment simulates the electron density profiles and reconstructs the plasma structure of the EIA at low latitudes, where the horizontal gradient is most significant. The reconstruction shows that artificial plasma caves are created underneath the EIA crests along with three density enhancements in adjacent latitudes. The artifact appears mainly below 250 km altitudes and becomes pronounced when the EIAs are well developed. Above that altitude, the two EIA features in the original (truth) model, the International Reference Ionosphere (IRI-2007), and in the inversion are similar, but the inversion reconstructs less distinct EIA crests with underestimation of the electron density. A simple correction has been introduced by multiplying the ratio between the truth and inversion with actual FORMOSAT-3/COSMIC observations. This initial correction shows that the artificial plasma caves are mitigated. Results also reveal that the RO technique is not suitable to detect or rule out possible existence of the plasma caves.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d779454s

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

2010-07-21T00:00:00Z

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