St. John's 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:Geological Survey of Canada

Publication_Date:1968

Title:

St. John's Magnetic Observatory

Online_Linkage:http://www.geolab.nrcan.gc.ca

Description:

Abstract:

The St. John's Geomagnetic Observatory began operation on 1 August, 1968. A location in southeastern Newfoundland was chosen to reduce one of the largest gaps in the geographical distribution of magnetic observatories in North America. In addition to contributing data for studies of worldwide geomagnetic variations and secular change, the St. John's Observatory provides control for the marine and airborne geomagnetic surveys conducted over the broad continental shelf east of Canada. The initial St. John's Observatory occupied a site 3 km northeast of the centre of the city, in the White Hills area, and was approximately 1.5 km from the sea. The area is magnetically flat and the total intensity varied by less than 15 nT within the initial site. A preliminary survey of geomagnetic time variations throughout Newfoundland revealed no gross electromagnetic induction anomalies in the St. John's region but some coastal induction effect must be expected and has in fact been found. 1968 Observatory: There were two non-magnetic buildings 100 m apart. The site was enclosed by an aluminum fence, segmented to avoid the disruption of the natural earth currents. One building was used both for the variometers and for absolute observations. It was 13 m long and 6.5 m wide, with the long axis magnetic north-south (1968), and was supported by concrete resting on the bedrock. It was of wooden construction, well insulated and covered with enamelled aluminum siding. Two reinforced and insulated concrete slabs, isolated from the walls of the building and from each other, provided support for the absolute instrument piers and the fluxgate magnetometer sensor, and for the photographic variometer tables respectively. Two insulated light-tight rooms enclosed the photographic instruments. The second building, about 8 m square, was of similar non- magnetic construction. It included an office, darkroom and laboratory in which the magnetic field was sufficiently undisturbed to have permitted the operation of many types of magnetometers. The buildings were connected by underground ducts carrying electrical power, signal and communication cables. The initial recording instrumentation consisted of a set of standard run RUSKA photographic variometers, a portable ASKANIA photographic variometer and a three component fluxgate magnetometer registering on an analogue paper chart recorder. St. John's was the first Canadian observatory to have a production run AMOS Mk I installed. Routine operation of the AMOS Mk I began in December, 1969 1975 Observatory: Following a decision of the Department of the Environment to construct a new office and laboratory complex, the New foundland Environment Institute, on Crown Land previously reserved for the Observatory, an agreement was reached whereby DOE would relocate the recording building 100 to 125 m to the northeast. This would ensure that the recordings of the magnetic variations would not be subject to interference from traffic on the access road leading to the new Institute. A total force survey in August, 1974 revealed no significant field gradients or anomalies within the proposed observatory site. Tenders for a new magnetic observatory building were called in April, 1975. The new building, having the same specifications as the 1968 13 m by 6.5 m building, was completed in December, 1975. The aging AMOS Mk I was replaced by the AMOS Mk III in mid- March, 1981. 1990 Observatory: Official notification by Public Works Canada (Atlantic Region) to the Earth Physics Branch indicated that the St. John's Observatory site was under considerable pressure for it to be developed for other Federal Government departments. As a result of discussions with Public Works during the summer of 1985, preliminary plans were formulated in order to move St. John's Observatory elsewhere in Newfoundland. A number of prospective sites were examined in the following 3 years but were found to be unsuitable for various reasons. In early 1988 the decision was made to move the Observatory an additional 500+ m back towards the northeast into the undeveloped White Hills Crown Land reserve. Site preparation and building construction were completed by the summer of 1989. The Observatory presently consists of a scattering of sensor huts and instrument buildings, all separated from each other by at least 30 m. Two 3 m by 5 m buildings of non-magnetic construction house the electronics racks and the absolute observation pier respectively. Five other prefabricated shelters house the various sensors and also serve as additional storage. Contrary to the usual detrimental effect of new construction on the local avifauna, a biological impact analysis by LeDrew Environmental Management Lt. showed a probable enhanced environment for the migratory snowy owls. Snowy owls nest in the White Hills area from fall to spring. Although the decrease in surface vegetation is probably appreciated by the snowy owls, it is most likely not looked upon with such enthusiasm by the local mice and shrew population. The third St. John's Observatory was placed in service in January, 1990 with the installation of the Geological Survey of Canada's prototype CANMOS. A fully INTERMAGNET compliant CANMOS was installed in March, 1991.

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: 100 meters

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date:1968

Ending_Date:Present

Currentness_Reference:

ground condition

Status:

Progress:In work

Maintenance_and_Update_Frequency:Irregular

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate:-64.27

East_Bounding_Coordinate:-64.27

North_Bounding_Coordinate:52.68

South_Bounding_Coordinate:52.68

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:Geological Survey of Canada

Contact_Person:L. McKee

Contact_Address:

Address_Type:mailing

Address:

7-Observatory Crescent

Address:

Contact institute

City:Newfoundland

State_or_Province:Ottawa

Postal_Code:K1A 0Y3

Country:Canada

Contact_Voice_Telephone:613-837-9158

Contact_Facsimile_Telephone:613-824-9803

Contact_Electronic_Mail_Address:Lmckee@NRCan.ca

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

Data from the St. John's Magnetic Observatory 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:Full field

Attribute_Accuracy_Explanation:

Dynamic Range

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:0.025 nT

Attribute_Accuracy_Explanation:

Resolution

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:8 Hz reduced by a boxcar filter to 1second data; 1 second data reduced to 5 second data

Attribute_Accuracy_Explanation:

Sampling Rate

Quantitative_Attribute_Accuracy_Assessment:

Attribute_Accuracy_Value:19 point Gaussian filter for the production of 1 minute data from 5 second data

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