Identification

Title

Thermosphere density variations due to the 15-24 April 2002 solar events from CHAMP/STAR accelerometer measurements

Abstract

Thermosphere densities near 410 km altitude between +/- 87 degrees latitude and near 0430 and 1530 local time from the accelerometer experiment on the CHAMP satellite are used to elucidate the response to three coronal mass ejections occurring on 17, 19, and 21 April 2002. Comparisons of the global responses with the NRLMSISE00 empirical model and the NCAR TIEGCM are performed and interpreted. An enhanced daytime response in comparison to TIEGCM on 17 April is found that is suggestive of preconditioning of the atmosphere due to enhanced solar EUV fluxes maximizing on 13 April. Out of several solar wind parameters and geophysical indices that were examined, the highest correlation with thermosphere densities occurred with respect to the magnitude of the interplanetary magnetic field as measured by the ACE spacecraft. Wave-like structures with scales ranging from 100s to 1000s of kilometers are also revealed in the CHAMP data. These structures are primarily a nighttime phenomena, and the associated total variance is correlated with magnetic activity throughout the 15-24 April 2002 period. The NCAR TIEGCM was utilized to provide the basis for interpreting the equatorward propagation of large-scale traveling atmospheric disturbance (TADs). Following a sudden increase in magnetic activity and high-latitude heating, TADs were launched from both hemispheres, traveled toward the equator with phase speeds of order 800 m s(-1), constructively interfered near the equator to produce a total density perturbation of similar to 20%, and then passed through each other and into the opposite hemisphere. Perspectives on future applications of CHAMP accelerometer data to elucidate magnetic storm-related perturbations of the thermosphere are outlined.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7pc3349

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

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South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2005-12-01T00:00:00Z

Frequency of update

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Conformity

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version of format

Constraints related to access and use

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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