Learmonth Magnetic Observatory

Metadata from the NOAA Metadata Manager's Repository (NMMR)

• Identification_Information
• Data_Quality_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator:Geoscience Australia (GA)

Publication_Date:1987

Title:

Learmonth Magnetic Observatory

Online_Linkage:http://www.ga.gov.au

Description:

Abstract:

The Learmonth Solar Observatory was established in 1977. In 1981 a request was received from the Ionospheric Prediction Service for assistance in monitoring variation in a single component of the magnetic field at the Solar Observatory. It was agreed that a full magnetic observatory should be established at the solar observatory. A Proton precession magnetometer was run at the site from October 1983 until the geomagnetic observatory was installed in November 1986. A three component EDA FM105B fluxgate magnetometer was initially installed at the observatory with an Elsec model 595 proton precession magnetometer. Magnetic variations were recorded on a chart recorder and minute averages were digitized and recorded on cassette using an EDAS-2 A/D data logger. The EDA fluxgate was installed in the HDZ orientation, which at Learmonth is within a degree of the XYZ orientation. At some stage the original Elsec 595 PPM was replaced with a Elsec 820 PPM. EDAS-2 cassette based data recording became unreliable and was replaced on 06:13UT 09 December 1992 (day 344) when a IBM compatible PC was introduced to log the data. Data logging has been performed by computer since that time. The EDAS-2 A/D data logger continued its function as an A/D converter for serial digital data input to the PC system until February 1999. The electronics consoles and data logger/Computer were installed in the Solar Observatory Radio Solar Telescope Network (RSTN) building. The fluxgate sensor was housed in a concrete vault, 800mm deep with 600mm sides which are partially buried. The vault was located approximetely 36 metres to the east of the RSTN building. The PPM sensor was initially mounted on a wooden pole about 10m from the fluxgate vault. In September 1995 a second underground vault was constructed to house the PPM sensor and the existing Elsec 820 PPM was replaced with a Geometrics G856 PPM. The EDA fluxgate was replaced with a Narod three axis ringcore fluxgate on 12 February 1999. The Narod instrument produced digital data so the EDAS-2 A/D converter was no longer needed. One channel of the Narod fluxgate developed a fault on 01 February 2000 and the whole instrument was replaced on 14 August 2001 with a Bartington MAG03MSL70 fluxgate and PAR24B 24 bit A/D converter. The Bartington variometer proved to be unstable and was replaced with a suspended DMI FGE three axis fluxgate variometer and ADAM 4017 A/D converter on 12 December 2001, Also at this time a third underground vault was constructed 3 metres from the fluxgate vault to house the DMI fluxgate variometer electronics.

Purpose:

To provide ground-based, calibrated values of the Earth's magnetic field at a specific location for scientific research and practical applications.

Supplemental_Information:

Elevation: 004 meters

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date:1987

Ending_Date:Present

Currentness_Reference:

ground condition

Status:

Progress:In work

Maintenance_and_Update_Frequency:Irregular

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate:114.10

East_Bounding_Coordinate:114.10

North_Bounding_Coordinate:-22.22

South_Bounding_Coordinate:-22.22

Keywords:

Theme:

Theme_Keyword_Thesaurus:NASA/GCMD Earth Science Keywords

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism > Geomagnetic Indices

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism > Magnetic Declination

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism > Magnetic Field

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism > Magnetic Inclination

Theme_Keyword:Earth Science > Solid Earth > Geomagnetism > Magnetic Intensity

Theme:

Theme_Keyword_Thesaurus:ISO 19115 Topic Category

Theme_Keyword:geoscientificInformation

Theme_Keyword:intelligenceMilitary

Theme_Keyword:utilitiesCommunication

Theme_Keyword:climatologyMeteorologyAtmosphere

Theme:

Theme_Keyword_Thesaurus:INTERMAGNET

Theme_Keyword:Magnetic Observatory Definitive Data

Access_Constraints:None

Use_Constraints:

None

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:Geoscience Australia

Contact_Person:Contact institute

Contact_Address:

Address_Type:mailing

Address:

Geomagnetism Group

Address:

G.P.O. Box 378

City:Canberra

State_or_Province:A.C.T.

Postal_Code:2601

Country:Australia

Contact_Voice_Telephone:+ 61-2-6249-9111

Contact_Facsimile_Telephone:+ 61-2-6249-9969

Contact_Electronic_Mail_Address:geomag@ga.gov.au

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Data from the Learmonth Magnetic Observatory met the requirements for being an INTERMAGNET Magnetic Observatory (IMO), and as such met the specifications listed in the INTERMAGNET Technical Manual (http://www.intermagnet.org//im_manual.pdf)

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:+/- 1600nT

Attribute_Accuracy_Explanation:

Dynamic Range

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:0.03nT

Attribute_Accuracy_Explanation:

Resolution

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:1 sec

Attribute_Accuracy_Explanation:

Sampling Rate

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:Mean values

Attribute_Accuracy_Explanation:

Numeric Filter

Logical_Consistency_Report:

Contact institution

Completeness_Report:

These data represent the complete record set for this station and this time period.

Lineage:

Process_Step:

Process_Description:

Contact institute

Source_Used_Citation_Abbreviation:

Unknown

Process_Date:Unknown

Entity_and_Attribute_Information:

Detailed_Description:

Entity_Type:

Entity_Type_Label:Magnetometer

Entity_Type_Definition:

A scientific instrument for measuring the strength of magnetic fields.

Entity_Type_Definition_Source:

http://en.wikipedia.org/wiki/Magnetometer

Attribute:

Attribute_Label:fluxgate magnetometer

Attribute_Definition:

A kind of magnetometer that detects second harmonic signals from a secondary coil surrounding an iron core that is driven into saturation by a primary coil using radio frequency signals. The second harmonic signal is proportional to the strength of the ambient magnetic field.

Attribute_Definition_Source:

http://www.earthsci.unimelb.edu.au/ES304/MODULES/MAG/NOTES/fluxgate.html

Attribute_Domain_Values:

Unrepresentable_Domain:

This is a type of magnetometer instrument used for measuring the Magnetic Field

Attribute:

Attribute_Label:proton precession magnetometer

Attribute_Definition:

A kind of scalar magnetometer that measures only the strength of the total magnetic field vector and not its direction or components. A hydrogen-rich fluid is polarized using a strong electric current. When the current is turned off, the protons in the fluid precess around the ambient magnetic field at a frequency given by the gyromagnetic ratio and proportional to the strength of the surrounding magnetic field.

Attribute_Definition_Source:

http://en.wikipedia.org/wiki/Magnetometer#Scalar_magnetometers

Attribute_Domain_Values:

Unrepresentable_Domain:

This is a type of magnetometer instrument used for measuring the Magnetic Field

Attribute:

Attribute_Label:Overhauser magnetometer

Attribute_Definition:

A type of scalar magnetometer that employs the precession of free unpaired electrons rather than protons in a fluid.

Attribute_Definition_Source:

http://en.wikipedia.org/wiki/Magnetometer#Scalar_magnetometers

Attribute_Domain_Values:

Unrepresentable_Domain:

This is a type of magnetometer instrument used for measuring the Magnetic Field

Detailed_Description:

Entity_Type:

Entity_Type_Label:Earth's Magnetic Field Components

Entity_Type_Definition:

The Earth's magnetic field is characterized by a direction and intensity which can be determined by various combinations of three of seven possible magnetic field components.

Entity_Type_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1970.

Attribute:

Attribute_Label:Inclination (I)

Attribute_Definition:

The angle which the line of force at a point of observation makes with the horizontal plane, positive when directed downward

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-90.0

Range_Domain_Maximum:90.0

Attribute_Units_of_Measure:Decimal Degrees or Degrees and Decimal Minutes

Attribute:

Attribute_Label:Declination (D)

Attribute_Definition:

The angle made by the magnetic meridian and the true north meridian, considered positive east of north and negative west of north

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-180.0

Range_Domain_Maximum:180.0

Attribute_Units_of_Measure:Decimal Degrees or Degrees and Decimal Minutes

Attribute:

Attribute_Label:Horizontal Intensity (H)

Attribute_Definition:

The projection of the geomagnetic field vector on the horizontal plane, always positive

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:0

Range_Domain_Maximum:40000.0

Attribute_Units_of_Measure:nanotesla

Attribute:

Attribute_Label:Vertical Intensity (Z)

Attribute_Definition:

The projection of the geomagnetic field vector on the vertical plane, positive when directed down

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-70000.0

Range_Domain_Maximum:60000.0

Attribute_Units_of_Measure:nanotesla

Attribute:

Attribute_Label:Total Intensity (F)

Attribute_Definition:

The scalar magnitude of the geomagnetic field vector, always positive

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:25000.0

Range_Domain_Maximum:80000.0

Attribute_Units_of_Measure:nanotesla

Attribute:

Attribute_Label:North Component (X)

Attribute_Definition:

The projection of the horizontal component (H) in the true meridian

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-10000.0

Range_Domain_Maximum:45000.0

Attribute_Units_of_Measure:nanotesla

Attribute:

Attribute_Label:East Component (Y)

Attribute_Definition:

The projection of the horizontal component on the true east direction, positive when directed eastward

Attribute_Definition_Source:

Wienert, K.A., Notes on geomagnetic observatory and survey practice, UNESCO Earth Sciences 5, 1971

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-20000.0

Range_Domain_Maximum:20000.0

Attribute_Units_of_Measure:nanotesla

Detailed_Description:

Entity_Type:

Entity_Type_Label:Geographic Location

Entity_Type_Definition:

A coordinate system that provides a means for expressing every location on the Earth using three coordinates of a spherical coordinate system which is aligned with the spin axis of the Earth.

Entity_Type_Definition_Source:

http://en.wikipedia.org/wiki/Geographic_location

Attribute:

Attribute_Label:Latitude

Attribute_Definition:

Latitude is an angular measurement in degrees that gives the location of a place on the Earth above (toward the North pole) or below (toward the South pole) of the equator.

Attribute_Definition_Source:

http://en.wikipedia.org/wiki/Latitude

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-90

Range_Domain_Maximum:+90

Attribute_Units_of_Measure:angular degrees

Attribute:

Attribute_Label:Longitude

Attribute_Definition:

Longitude is an angluar measurement in degrees that describes the location of a place on the Earth east or west of a north-south line called the Prime Meridian.

Attribute_Definition_Source:

http://en.wikipedia.org/wiki/Longitude

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:-180

Range_Domain_Maximum:+180

Attribute_Units_of_Measure:angular degrees

Attribute:

Attribute_Label:Elevation

Attribute_Definition:

Elevation is the vertical position of a location relative to some height above the Earth's surface, generally taken as the mean sea level or geoid.

Attribute_Definition_Source:

http://en.wikipedia.org/wiki/Geoid

Attribute_Domain_Values:

Range_Domain:

Range_Domain_Minimum:0

Range_Domain_Maximum:unlimited

Attribute_Units_of_Measure:meters

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce

Contact_Person:David Fischman

Contact_Position:Data Manager

Contact_Address:

Address_Type:mailing and physical

Address:

325 Broadway

City:Boulder

State_or_Province:CO

Postal_Code:80303

Country:USA

Contact_Voice_Telephone:303 497-4654

Contact_Facsimile_Telephone:303-497-6513

Contact_Electronic_Mail_Address:david.fischman@noaa.gov

Hours_of_Service:8:00 - 5:00 Mountain

Distribution_Liability:

While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name:IAGA2002

Format_Version_Date:2001

Format_Specification:

http://www.ngdc.noaa.gov/IAGA/vdat/iagaformat.html

Format_Information_Content:

Columnar ASCII values including date, time, and magnetic field values, including header information pertinate to the individual observatory.

File_Decompression_Technique:generally ZIP

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:http://www.ngdc.noaa.gov/IAGA/vdat/iagaformat.html

Digital_Form:

Digital_Transfer_Information:

Format_Name:WDC-A

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:www.wdcb.ru/stp/data/geo_min.val/AIA-Argentine%20Islands/DIGITAL%20WDC%20FORMATS.doc

Access_Instructions:

This is an outdated ASCII format.

Fees:None

Ordering_Instructions:

Contact NGDC for instructions.

Metadata_Reference_Information:

Metadata_Date:

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization:DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce

Contact_Person:David Fischman

Contact_Position:Data Manager

Contact_Address:

Address_Type:mailing and physical

Address:

325 Broadway

City:Boulder

State_or_Province:CO

Postal_Code:80303

Country:USA

Contact_Voice_Telephone:303 497-4654

Contact_Facsimile_Telephone:303-497-6513

Contact_Electronic_Mail_Address:david.fischman@noaa.gov

Hours_of_Service:8:00 - 5:00 Mountain

Metadata_Standard_Name:Content Standard for Digital Geospatial Metadata: Extensions for Remote Sensing Metadata

Metadata_Standard_Version:FGDC-STD-012-2002

Metadata_Extensions:

Online_Linkage:http://www.ngdc.noaa.gov/metadata/extensions/local_extensions.html

Profile_Name:NGDC Extensions to FGDC Metadata