Land and sea ice sructure west and south of Ross Island measured by ground penetrating radar, UAV, and helicopter EM bird
Entry ID:
K053_2009_2012_NZ_1
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Summary
Abstract:
This data set decribes surface and volume properties of snow and ice to validate radar satellite measurements. Ground penetrating radar (GPR) at 500 and 1000GHz provides information on snow layers and thickness near the surface at two sites on the McMurdo Ice Shelf, one site at Ross Island, and on the landfast and new sea ice in McMurdo Sound. A 50MHz antenna is used to measure total ice thickness ... and the thickness of the ice above the saline layer underneath the ice shelf. Snow density and morphology is measured in snow pits using standard glaciological methods and an infrared camera, as well as an ice corer for depths down to about 8m. Snow stakes were used to measure the annual accumulation on land ice over a one year period. A dust layer is used to quantify the average accumulation over a 5 year period. Stake and GPR measurements suggest a high temporal and spatial variabilty in snow accumulation near Ross Island. A laser ranger on the skidoo and a small unmanned aircraft are used to determine the surface roughness of snow on land ice. For sea ice, the GPR system is used on one north south and two east-west transects to measure snow thickness on ice. Ice drilling is used to determine total sea ice thickness along the transects. A helicopter EM bird is used to measure a grid of sea ice and ice shelf thickness across the McMurdo Sound. Ground measurements validate the performance of the HEM bird in the presence of platelet ice.
In 2011 more in-depth research was conducted into sea ice thickness. The subice platelet layer thickness under sea ice was measured in regular intervals at two North-South oriented profiles and four east-west oriented profiles. Holes were drilled at regular intervals into sea ice at measurement sites about 5 km apart. At these holes sea ice thickness and snow depth on top of the sea ice was measured. In between the sites, sea ice thickness was measured using an electromagnetic induction device, and snow on sea ice was measured using a ground penetrating radar system. Ocean temperature and salinity was measured through holes in the sea ice along the ice edge of the McMurdo Ice Shelf within 3 km of the ice shelf front. The response of the sea ice to tidal height was measured at three locations using GPS Stations. At these locations samples of sea ice were taken for geophysical, oceanographic and biological analysis. Water samples were also taken.
Sea ice thickness (surface elevation and draft of sea ice) and surface reflectance was measured along ten North-South oriented profiles and eight east-west oriented profiles. This was performed by the HEM bird and the ground measurements validate these results. 
Geographic Coverage
(Click for Interactive Map)
Spatial coordinates
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3.
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N: -77.03
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S: -78.04
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E: 167.48
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W: 163.64
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4.
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N: -77.67
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S: -77.87
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E: 166.5
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W: 165.33
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Quality
At Davis, where the water depth near the station is relatively shallow, there is little heat transfer from the ocean to the ice, and the thickness is largely determined by atmospheric conditions, predominantly temperature and snow cover. At Mawson, where ocean depths are over 200 m, interannual variability of ice thickness is also influenced by changes in oceanic heat flux.
... Long-term statistics are maintained for each site of the date of ice formation, maximum thickness, date of maximum thickness, date of any mid-season breakouts, and date of final breakout of the fast ice. Incomplete historical records exist for Mawson back to 1954 and for Davis back to 1958.
Simple (e.g. Allison, 1981) or more complex (Heil et al., 1996) thermodynamic modelling of the growth of the ice cover can be used to estimate seasonal and interannual variations in the oceanic heat flux.
Access Constraints
These data are publicly available for download from the URL given below.
A pdf document detailing how the data are collected is 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 at the provided URL when using these data.
Data Set Progress
IN WORK
Distribution
Distribution Media:
HTTP
Distribution Size:
407 kb
Distribution Format:
word documents
Fees:
free
Distribution Media:
HTTP
Distribution Size:
2,511 kb
Distribution Format:
pdf
Fees:
free
Personnel
Role:
INVESTIGATOR
Phone:
+61 3 6226 7648
Fax:
+61 3 6226 7650
Email:
ian.allison at aad.gov.au
Contact Address:
Australian Antarctic Division
203 Channel Highway
City:
Kingston
Province or State:
Tasmania
Postal Code:
7050
Country:
Australia
Role:
DIF AUTHOR
Contact Address:
Australian Antarctic Division
203 Channel Highway
City:
Kingston
Province or State:
Tasmania
Postal Code:
7050
Country:
Australia
Publications/References
Allison, I. (1981). Antarctic sea ice growth and oceanic heat flux. In: I. Allison (Ed.). Sea level, ice and climate change. IAHS Publication, 131, 161-170. Allison, I. and Qian, S.L. (1985). Characteristics of sea ice in the Casey region. In: T.H. Jacka (Ed.). Australian Glaciological Research; 1982-83. ANARE Research Notes, 28, pp. 47-56. Allison, I. (1986) Sea ... ice thickness observations at Australian coastal antarctic stations. Glaciology Section Internal Report, 64 pp.
Heil, P., I. Allison, and V.I. Lytle (1996) Seasonal and interannual variations of the oceanic heat flux under a landfast Antarctic sea ice cover. J. Geophys. Res., 101(C11), 25,741-25,752.
Heil, P. (submitted) Interactions between fast ice and local atmospheric conditions at Davis Station, Antarctica: a case study. J. Climate.
Mellor, M. (1960) Sea ice measurements at Mawson and Davis, 1954-58. ANARE Interim Report, 19.
Creation and Review Dates
DIF Creation Date:
2001-08-27
Last DIF Revision Date:
2010-07-28
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