Identification

Title

Dependence of the high-latitude thermospheric densities on the interplanetary magnetic field

Abstract

The systematic analysis of the interplanetary magnetic field (IMF) By and Bz influences on observed thermospheric density is presented. For this purpose, the high-latitude southern summer thermospheric total mass density near 400 km altitude, derived from the high-accuracy accelerometer on board the Challenging Minisatellite Payload (CHAMP) spacecraft, is statistically analyzed in magnetic coordinates. The difference density distributions, which are obtained by subtracting values for zero IMF from those for nonzero IMF, vary strongly with respect to the direction of the IMF: Difference densities for negative By show significant enhancements in the early morning hours and hours around dawn but show reduced values in the dusk sector. For positive By the difference densities are opposite in sign to those for negative By. Density differences for negative Bz show significant increases in the cusp region and premidnight sector but a small decrease in the dawn sector. The difference densities at high latitudes tend to be weakest when Bz is positive. We suggest that the high-latitude thermospheric density variations for different IMF conditions, especially in the dawn and dusk sectors, can be strongly determined by thermospheric winds, which are associated with the ionospheric convection and vary strongly with respect to the IMF direction. We also suggest that density variations, especially in auroral and cusp regions, are also influenced by the local heating associated with ionospheric currents, which vary with IMF conditions.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7fn1774

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

2009-05-12T00:00:00Z

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