Pacific Arctic Group meeting in Shanghai, 2006
In situ measurement techniques and methods:
sea ice thickness
Sun Bo, Guo Jingxue, Li Na, Li Bingrui
Polar Research Institute of China
E-mail: [email protected]
http://pric.gov.cn
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The Issue : sea ice thickness
1. One critical parameter
Knowledge of Ice thickness is one critical parameter for understanding sea
ice evolution，mass balance and simulating the behaviors of ice-oceanatmosphere interaction
2. also the most difficult geophysical parameters to measure
largely because of the fact that there is no reliable way to directly measure
them based on satellite remote sensing
3. one of the largest uncertainties on the geophysics of sea ice
changes
an increasing need to develop new technique and method to measure sea ice
thickness.
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Current techniques
So far, five direct techniques have been commonly employed for
measuring sea ice thickness in polar regions:
• submarine sonar profiling
• moored upward sonars
• airborne laser profilometry
• airborne and ground electromagnetic techniques
• drilling
(Rothrock et al., 1999)
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(Haas et al.,)
In situ electromagnetic techniques and methods in sea ice physics
• Ground-penetrating radar (GPR) in sea ice
• Electro-magnetic Induction in SEA ice
Sea ice
Sea water
GPR
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EMI
In situ electromagnetic techniques and methods in sea ice physics
• Ground-penetrating radar (GPR) in sea ice
With the developments in ground penetrating radar
(GPR) technology and signal processing methods may offer
a powerful tool to measure the geophysics of sea ice.
(1) the capabilities of the GPR measuring sea
ice thickness;
(2) the features of subice morphology
described from radar images;
(3) how useful 3-D GPR methods and radar
data analyses are for distinguishing and
analyzing the subice morphology.
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Sea
ice
Sea water
Ground-penetrating radar (GPR) in sea ice
Using two- and three-dimensional GPR methods to characterize
ice thickness and its underside morphology on Arctic summer sea ice
the distribution of radar surveys sites and the 3D grid
surveying lines pattern
(a) Sketch map of experiment area
the dots indicate the radar 2D sites, triangle indicates the 3D
site
(b) the grid surveying pattern on an undeformed ice floe
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pulseEKKO GPR radar
Using two- and three-dimensional GPR methods to characterize
ice thickness and its underside morphology on Arctic summer sea ice
A section of two-dimensional GPR profile image from Arctic sea ice
Figure Sea ice bottom topography and
its contour
(vertical : horizontal exaggeration is 15:1)
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In situ electromagnetic techniques and methods in sea ice physics
• Electromagnetic Measurements (EMI) in sea ice
Electromagnetic induction (EMI) sounding has
become an operational tool for sea ice thickness
profiling on the ice, from ships and helicopters
Haas,2004
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Arctic sea ice thickness measurements in Chinese
Planning for IPY activities.
In situ sea ice thickness measurements using
electromagnetic techniques in Pacific Arctic Sector.
Questions: how cooperate using
the platform of PAG
We welcome discussion about future activities with
relevant partners on topics of mutual interest
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Thanks for your attention!
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