Radio-echo sounding (RES) ice thickness data: LGB traverses 1990-95

Federal Geographic Data Committee (FGDC) Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: Unknown
Publication_Date: Unknown
Title: Radio-echo sounding (RES) ice thickness data: LGB traverses 1990-95
Description:
Abstract:
The Lambert Glacier Basin (LGB) series of five oversnow traverses were conducted from 1989-95. The ANARE 100 MHz digital ice radar operated from the second traverse (1990/91) and recorded ice thicknesses approximately every 10-15 m along three routes: the 2014 km main traverse track from LGB00 (68.6543 S, 61.1201 E) near Mawson to LGB72 (69.9209 S, 76.4933 E) near Davis; the 516 km upper western offset track (50 km parallel upslope from main route) from LGBUW485 (68.6458 S, 60.0272 E) to LGBUW000 (72.6508 S, 55.9275 E); and the 560 km south western offset track from LGBUW485 to LGBOS01 (76.5152 S, 63.9098 E). RES data for ice thickness measurements constituted a major component in the study of the mass budget and dynamics of the interior Lambert Glacier basin. Raw data were stored in 200 kb binary files containing 200 x 1024 x 8 bit sample waveforms giving approximately 10 m spacing between ice thickness values, together with a header field describing relevant parameters associated with each 2 km long section of track. Processed data were stored as 2 km averaged ice thickness spreadsheet files (MS Excel), or 100 m spatial resolution EPS files for plotting signal profiles. The data available at the url below are stored in various formats. Summary data (2 km spatial average) can be obtained from CRC Research Note No.27 'Ice Thicknesses and Surface and Bedrock Elevations from the Lambert Glacier Basin Traverses 1990-95'. Documents providing archive details of the logbooks are available for download from the provided URL. This work was completed as part of ASAC projects 3 and 2216.
Purpose:
Not Available
Supplemental_Information:
Not Available
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19901101
Ending_Date: 19950228
Currentness_Reference:Unknown
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Description_of_Geographic_Extent:
Bounding_Coordinates:
West_Bounding_Coordinate: 54.0
East_Bounding_Coordinate: 78.0
North_Bounding_Coordinate: -69.0
South_Bounding_Coordinate: -77.0
Keywords:
Theme:
Theme_Keyword_Thesaurus: GCMD SCIENCE PARAMETERS
Theme_Keyword_Thesaurus: GCMD PLATFORM
Theme_Keyword_Thesaurus: ANCILLARY KEYWORDS
Theme_Keyword_Thesaurus: ISO TOPIC CATEGORY
Theme_Keyword_Thesaurus: DATA SET LANGUAGE
Theme_Keyword: EARTH SCIENCE > CRYOSPHERE > GLACIERS/ICE SHEETS > GLACIERS
Theme_Keyword: EARTH SCIENCE > CRYOSPHERE > SNOW/ICE > ICE DEPTH/THICKNESS
Theme_Keyword: EARTH SCIENCE > SPECTRAL/ENGINEERING > RADIO WAVE
Theme_Keyword: FIELD SURVEYS
Theme_Keyword: Antarctica
Theme_Keyword: Glacier
Theme_Keyword: Ice Thickness
Theme_Keyword: GEOSCIENTIFIC INFORMATION
Theme_Keyword: IMAGERY/BASE MAPS/EARTH COVER
Theme_Keyword: INLAND WATERS
Theme_Keyword: ENGLISH
Place:
Place_Keyword_Thesaurus: GCMD
Place_Keyword: CONTINENT > ANTARCTICA > LAMBERT GLACIER
Place_Keyword: GEOGRAPHIC REGION > POLAR
Access_Constraints: The data are available from the url given below. Documents providing archive details of the logbooks are also available for download from the provided URL.
Use_Constraints:
This data set conforms to the PICCCBY Attribution License (http://creativecommons.org/licenses/by/3.0/). Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=LGB_RES_traverse when using these data.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: IAN ALLISON
Contact_Position: TECHNICAL CONTACT
Contact_Position: INVESTIGATOR
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Australian Antarctic Division
Address: 203 Channel Highway
City: Kingston
State_or_Province: Tasmania
Postal_Code: 7050
Country: Australia
Contact_Voice_Telephone: +61 3 6226 7648
Contact_Facsimile_Telephone: +61 3 6226 7650
Contact_Electronic_Mail_Address: ian.allison@aad.gov.au
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Small gaps in the data arose from loss of signal return in areas of extremely deep ice and/or internal reflections from complex structures within the ice. On a 2 km spatially averaged resolution these gaps have been compensated for by gravity interpolation of ice thicknesses. The ANARE Mk Vb 100 MHz ice radar produced peak power of 3 kW with a pulse duration of 250 ns and repetition rate of 10 kHz. An antenna array of 2 transmit and 4 receive yagis (1 driven element, 2 directors, 1 reflector) was used in 1990/91 and 1992/93, whilst an array of 1 transmit and 2 receive corner reflectors were used in 1993/94 and 1994/95. The radar unit operated from a sled-mounted van towed by a Caterpillar D7H tractor, moving at an average speed of 5 km/hr. Linear and logarithmic amplifier stages passed the return signal (using a 3 ms transmit pulse suppression technique) to a digital storage oscilloscope (DSO), which continuously averaged incoming pulses before transmitting to file every 5-10 s (as preset). The averaging resulted in a better than 20 dB signal-to-noise- ratio. Signal propagation delay times were converted to ice thicknesses assuming a velocity of 169 m/microsecond with no firn correction. A header section was attached to file containing information including navigational GPS (pseudo-range) positioning for each 10 m averaged data point. A semi- automated data processing routine produced RES profiles as EPS files for printing, or ASCII files for importing into spreadsheet programs (MS Excel) for further analysis. The data have been checked externally with 2 km spaced gravity readings and internally by repeat measurement over several sections of traverse track. Ice thickness values were accurate to within 20 m over 2000 m depth. Geographic locations for which ice thickness values applied were navigational GPS (30-100 m accuracy) constrained to overnight LGB station geodetic GPS fixes (1-5 m horizontal) every 30 km along the main traverse route, and of similar accuracy for the parallel offset lines.
Logical_Consistency_Report:
Not Available
Completeness_Report:
Not Available
Lineage:
Process_Step:
Process_Description:
Not Available
Process_Date: Unknown
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Spatial_Reference_Information:
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: AU/AADC > Australian Antarctic Data Centre, Australia
Contact_Person: DATA OFFICER AADC
Contact_Position: DATA CENTER CONTACT
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Australian Antarctic Division
Address: 203 Channel Highway
City: Kingston
State_or_Province: Tasmania
Postal_Code: 7050
Country: Australia
Contact_Voice_Telephone: +61 3 6232 3244
Contact_Facsimile_Telephone: +61 3 6232 3351
Contact_Electronic_Mail_Address: metadata@aad.gov.au
Resource_Description: LGB_RES_traverse
Distribution_Liability:
Not Available
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: pdf
Transfer_Size: 4435 KB
Transfer_Size: 61 KB
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://data.aad.gov.au
Access_Instructions:
DATA CENTER URL
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://data.aad.gov.au/aadc/portal/download_file.c...
Access_Instructions:
Download point for the data
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
https://secure3.aad.gov.au/proms/public/projects/r...
Access_Instructions:
Public information for ASAC project 3
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
https://secure3.aad.gov.au/proms/public/projects/r...
Access_Instructions:
Public information for ASAC project 2216
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://data.aad.gov.au/aadc/portal/download_file.c...
Access_Instructions:
Download point for the catalogue information for the logbooks
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://data.aad.gov.au/aadc/metadata/citation.cfm?...
Access_Instructions:
Citation reference for this metadata record and dataset
Fees: Free
Fees: Free
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Metadata_Reference_Information:
Metadata_Date: 19991007
Metadata_Review_Date: 20140110
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: DAVE J. CONNELL
Contact_Position: DIF AUTHOR
Contact_Address:
Address_Type: Mailing and Physical Address
Address: Australian Antarctic Division
Address: 203 Channel Highway
City: Kingston
State_or_Province: Tasmania
Postal_Code: 7050
Country: Australia
Contact_Voice_Telephone: +61 3 6232 3244
Contact_Facsimile_Telephone: +61 3 6232 3351
Contact_Electronic_Mail_Address: dave.connell@aad.gov.au
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
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