Analysis of East Antarctic drainage basins with altimetric, interferometric, gravity and GPS techniques to determine their state of flux

Federal Geographic Data Committee (FGDC) Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Reference_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Unknown

Publication_Date: Unknown

Title: Analysis of East Antarctic drainage basins with altimetric, interferometric, gravity and GPS techniques to determine their state of flux

Description:

Abstract:

Metadata record for data from ASAC Project 2788 See the link below for public details on this project. Public This project will reassess the mass balance of Law Dome and a large sector of the Antarctic ice sheet south of Casey by exploiting the time history of change that can be obtained by resurveying historical surface elevation and gravity networks, started in the 1960s. The changes in position and gravity from these terrestrial traverses act as important constraints and, in some cases, calibration for recent satellite altimeter missions. Such a reassessment and model improvement should see a significant drop in the current uncertainty of the contribution of the Antarctic ice sheet to global sea level rise. 2007-2008 Season: Historical and recent data over Law Dome has been successfully re-reduced and integrated with recent satellite data over a period spanning 1962 to 2005. These data show that the surface elevation of Law Dome decreased from 1962 to about 1971 and then generally increased till 2005 indicating that ice volumes have recently varied over decadal time spans. The variations that are present within our gravity data set are in agreement with the deep core stratigraphy results from the Law Dome summit. Since our data cover the full extent of Law Dome, we are able to state with good confidence that the changes we see are consistent with climate-related signals where increased precipitation is due to increased atmospheric water vapour. This phenomenon has been reported in the Norwegian Arctic. The detection of these localised complex changes, over decadal time scales , highlights problems associated with interpreting relatively short time scale altimetric measurements.

Purpose:

Not Available

Supplemental_Information:

REFERENCE: Watson C., Tregoning P., Coleman R. 2006 Impact of solid Earth tide models on GPS coordinate and tropospheric time series Geophysical Research Letters 33 L08306 doi:10.1029/2005GL025538

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20071001

Ending_Date: 20090331

Currentness_Reference:Unknown

Status:

Progress: Complete

Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Description_of_Geographic_Extent:

Bounding_Coordinates:

West_Bounding_Coordinate: 110.0

East_Bounding_Coordinate: 111.0

North_Bounding_Coordinate: -66.0

South_Bounding_Coordinate: -67.0

Keywords:

Theme:

Theme_Keyword_Thesaurus: GCMD SCIENCE PARAMETERS

Theme_Keyword_Thesaurus: GCMD PLATFORM

Theme_Keyword_Thesaurus: GCMD INSTRUMENT

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 > ICE SHEETS

Theme_Keyword: EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > CONTOURS

Theme_Keyword: EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > LANDFORMS

Theme_Keyword: EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION

Theme_Keyword: EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY

Theme_Keyword: EARTH SCIENCE > CRYOSPHERE > GLACIERS/ICE SHEETS > GLACIER THICKNESS/ICE SHEET THICKNESS

Theme_Keyword: GPS > GLOBAL POSITIONING SYSTEM SATELLITES

Theme_Keyword: GPS > GLOBAL POSITIONING SYSTEM

Theme_Keyword: GPS RECEIVERS

Theme_Keyword: Gps

Theme_Keyword: Drainage Basins

Theme_Keyword: IMAGERY/BASE MAPS/EARTH COVER

Theme_Keyword: ENGLISH

Place:

Place_Keyword_Thesaurus: GCMD

Place_Keyword: CONTINENT > ANTARCTICA

Place_Keyword: GEOGRAPHIC REGION > ARCTIC

Place_Keyword: GEOGRAPHIC REGION > POLAR

Access_Constraints: These data are publicly 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=ASAC_2788 when using these data.

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: RICHARD COLEMAN

Contact_Position: INVESTIGATOR

Contact_Position: TECHNICAL CONTACT

Contact_Address:

Address_Type: Mailing and Physical Address

Address: Centre for Spatial Information Science

Address: School of Geography and Environmental Studies

Address: University of Tasmania

Address: Private Bag 76

City: Hobart

State_or_Province: Tasmania

Postal_Code: 7001

Country: Australia

Contact_Voice_Telephone: +61 3 6226 2108

Contact_Facsimile_Telephone: +61 3 6224 0282

Contact_Electronic_Mail_Address: Richard.Coleman@utas.edu.au

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The Dates provided in temporal coverage are approximate only, and represent the beginning and end of the 2007 - 2009 Antarctic seasons. The latitudes and longitudes provided in spatial coverage are approximate only. 2007-2008 Season: Objective 1 - all available gravity data over a 40yr period has been verified, checked, calibrated and adjusted so that we have the most complete reduced gravity dataset for the Law Dome area. All available GPS data has been reduced from that data collected during 2004-05 field season. All available GPS data collected during 2004-05 field season has been reduced. A significant portion of the GPS data has been validated and inter compared using different reduction techniques in order to understand errors particularly in L1 pseudo range data. This objective is now some 70% complete. The remaining work refers to the deep south lines, generally south of 70 degrees south. The gravity data have been adjusted but not yet navigated for precise position, that is, assigned WGS84 coordinates. The data entry from paper records is the current hurdle. Objective 2 - A re-occupation of earlier survey control lines was done using GPS in season 2004-05(limited by logistical support), attempts to get back into the field in later seasons have not been possible (priority to the aircraft/runway). Attempts were made in season 07-08 to revisit some of our GPS sites to located and extend poles to save the value of the science for future seasons. This was not possible and/or not successful so if we do future work, the surveys will have to start again as past information is lost. This objective has not been possible due to the lack of field support after the first season. We are now fearful of losing all scientific value from the 2004-2005 data as the deep holes placed to determine horizontal/vertical change are now buried and are likely never to be recovered as the precision of real time location is about 2 meters and their depth will be in excess of 2 meters. The possible exception for recovery may be the 100m borehole placed by the ice core group for us Objective 3 - a paper has been submitted to the Australian Journal of Earth Sciences (Bailey, Morgan, Lackie) and is currently in review. This paper has now been rejected, principally due to GPS positioning results which were deemed to be too good to be true. We are seeking an alternative journal. See documentation within the download file for further information.

Logical_Consistency_Report:

Not Available

Completeness_Report:

Not Available

Lineage:

Process_Step:

Process_Description:

Not Available

Process_Date: Unknown

Spatial_Reference_Information:

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: ASAC_2788

Distribution_Liability:

Not Available

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: text, excel, binary

Transfer_Size: 420 MB

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 2788

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

Metadata_Reference_Information:

Metadata_Date: 20060727

Metadata_Review_Date: 20120201

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: DAVE 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