Identification

Title

Long-term changes in solar quiet (Sq) geomagnetic variations related to Earth's magnetic field secular variation

Abstract

The daily amplitude of the solar quiet (Sq) magnetic variation of the horizontal intensity, H, of observatories at low and midlatitudes is analyzed, in search of significant long-term trends. These trends are expected based on secular variations of the Earth's magnetic field (B) and increasing concentrations of greenhouse gases which can affect Sq for instance through their effect on ionospheric conductivities and E-region electron concentration. The hourly horizontal geomagnetic field component, H, measured at Apia, Fredericksburg, Hermanus, Bangui, and Trivandrum was analyzed for the period 1960-2000. The solar activity effect was filtered out from the daily Sq amplitude of H, and then linear trends were calculated and compared to trend values obtained from the Coupled Magnetosphere-Ionosphere-Thermosphere model. Linear trends were calculated separately for periods of different secular trends in the magnetic field intensity, B. We found significant trends in experimental data for Apia, Fredericksburg, Hermanus, and for the period 1960-1983 for Bangui. There is reasonable quantitative agreement between experimental and simulated trends, and a qualitative agreement with trends expected from the secular trend in B.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d76974f7

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

2013-06-18T00:00:00Z

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