sea ice overview - crrc · university of alaska fairbanks [email protected] winter and...
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Sea Ice OverviewChris PetrichGeophysical Institute
Seasonal cycle:
University of Alaska [email protected]
Winter and spring: landfast ice (immobile) and pack ice (moving)Summer and fall: pack ice (moving) or no ice
Seasonal cycle:
Pack ice movement : Beaufort Gyre vs. Chukchi Sea
Landfast ice in Beaufort Sea vs. Chukchi Sea: Differences in Extent and Timing
Contact points between oil and iceNRDA in Arctic Waters, 20 Apr 2010
Age of Sea Ice in the Arctic
pack ice is getting younger(thinner)
UNEP, Global Outlook for Ice and Snow (2007),based on State of the Arctic Report (2006)
Seasonal Sea Ice Cycle
“winter” “summer”
Offshore leases & the sea ice environmentthe sea‐ice environment
in pack ice
in landfast ice
Landfast ice extent (May)
Lead/polynya occurrence probabilityprobability >0.2 in May
Data & reports:pmms.gina.alaska.edu
Landfast Ice
Bottomfast ice
Floatinglandfast ice
GroundedLandfast ice extensions
Pack ice
ridges
(Mahoney)m
, Barrow
Landfast Ice EdgeGroundedPressure Ridge
Open Water and
Landfast IceExtension
Pack Ice
Extension
Chris PetrichChukchi Sea
Barrow, Jan 2009
Landfast Ice Edge
Bill HBill Hess
Beaufort SeaChukchi Sea
Beaufort Seapack ice
pack ice landfast icef
lead
AVHRR, 23 March 2005
Beaufort SeaBeaufort Gyre
Chukchi SeaBeaufort Seapack ice
pack ice landfast icef
lead
AVHRR, 23 March 2005
Beaufort SeaChukchi Sea
Beaufort Seapack ice
pack ice landfast icef
lead
AVHRR, 23 March 2005
Lead Occurrence Patterns (1993‐2004)
March
Landfast ice zone widerwider
in Beaufort Seathan
300 milesthan
in Chukchi Sea(Mahoney et al., 2007)
Landfast Ice in Chukchi vs. Beaufort: Different Timing
(Mahoney et al., 2007)( y , )
Landfast Ice in Chukchi vs. Beaufort: Different Timing
“LandfastIce‐Free”
(Mahoney et al., 2007)( y , )
An Anecdote of 2006August Septemberg
S 5 2006
Coastal pack ice all summer: 2006Sept 5, 2006
sea iceoffshoreoffshoreleases
Barrow PrudhoeBay
Courtesy: MODIS Rapid Response TeamAERONET_Barrow.2006248.terra.1km.jpg
Bay
Points of interaction between oil and ice
AMAP Assessment Report 1998
Oil in ice‐covered waters
Example of oil encapsulation
NORCOR, 1975
Arctic Ocean Diversity (ArcOD)
seaice
microalgae
C. Krembs