Wednesday, September 4, 2013

DRY LAB? How do you publish a Government document in September 2013 which claims to present October, November 2013 and January 2014 facts? WTHO? NO PEER REVIEW. POOR WRITING FAILS TO BE CLEAR. 2012 DATA PRESENTED IN 2013 ATLAS? YOU DECIDE.

Annual Arctic Ice Atlas 2013

The 2013 Annual Arctic Ice Atlas is part of a continuing series, prepared each year by the Canadian Ice Service since 1990. This collection of atlases documents Canadian Arctic winter sea ice conditions to provide a comparison from year to year. In each atlas, ice formation during the freeze-up period is first described. This is then followed by graphical depictions of the winter ice conditions, primarily based on synthetic aperture radar (SAR) data.
The SAR data used in the compilation of the image mosaics in this year’s atlas primarily came from the RADARSAT-2 satellite. The data were captured by the Prince Albert (Saskatchewan) and Gatineau (Quebec) receiving stations, between February 2nd and February 28th, 2013.
In this atlas the Arctic is divided up into five main regions and four larger-scale snapshot regions. All of the main regions (Metarea17, Metarea18, the Eastern Arctic, the Western Arctic, and Hudson Bay) include an analysis of the data as well as a SAR image mosaic. The ice analyses were created by Environment Canada's Canadian Ice Service (CIS) personnel, who used additional supporting information (including meteorological summaries, ice thickness reports and NOAA AVHRR imagery) in their preparation. An explanation of the nomenclature on the analysis charts can be found on the Sea Ice Symbols page. A more detailed explanation of the terminologies used is available in MANICE (Manual of Standard Procedures for Observing and Reporting Ice Conditions), prepared by Environment Canada's Meteorological Service.
For most regions, the SAR image mosaic represents a composite of orbits from several days. The period over which the data were acquired is noted on each page. Basic geographic annotation is provided on the mosaics as a reference. During the image production, the raw data were radiometrically adjusted and enhanced. The overlapping orbits were then digitally seamed together to give a balanced and finished picture. For the main regions, although the SAR data were captured at a resolution of 50 metres pixel-1, the data were analyzed at approximately 100 metres pixel-1 and the published image mosaics were resampled to approximately 800 metres pixel-1. For the snapshot regions, the SAR data were captured at a resolution of approximately 25 metres pixel-1, analyzed at 25 metres pixel-1, and the published images were resampled to approximately 200 metres pixel-1.
All the RADARSAT-2 images contained in this atlas were processed by and are the property of the MacDonald, Dettwiler, and Associates Ltd. (MDA), and are copyright © MDA 2013 - All Rights Reserved. RADARSAT is an official mark of the Canadian Space Agency. All data acquired for this atlas has been archived by the Canadian Centre for Remote Sensing (CCRS). This atlas has been published with the permission of MDA.
The successful completion of this project was made possible with the able assistance of many people. The following contributions should be noted:
  • Project Manager: Dan Fequet (CIS)
  • RADARSAT SAR data acquisition: MDA, Céline Fabi and Kathy Clevers (CIS)
  • Mosaic production: Emma  Nussli (CIS-COOP)
  • Image analysis: Trudy Wohlleben, Denis Dubé, Luc Desjardins and Jeanine Laing (CIS)
  • Freeze-up and Winter summary: Trudy Wohlleben (CIS)

Annual Arctic Ice Atlas 2013


Hudson Bay and Approaches

Air Temperatures

During the first part of the freeze-up period, from the beginning of October to the end of November, mean air temperatures averaged 1-2°C above the 1981-2010 normal over Hudson Bay and 2-3°C above normal in Foxe Basin, Hudson Strait and along the Labrador Coast. Average temperatures in December then rose to 3-6°C above normal over Hudson Bay, Foxe Basin and between Frobisher Bay and the north Labrador coast, with a local hotspot averaging greater than 6°C above normal in Hudson Strait. In January, mean air temperatures over Hudson Bay returned to near normal except in the west where they averaged 1-3°C below normal. Air temperatures elsewhere averaged 2°C above normal or more, except along the southern section of the Labrador coast where they were near normal. Locally, in January, average temperatures reached 4°C above normal in northeastern Foxe Basin and 5°C above normal southwest of Baffin Island.

Ice Conditions Summary

Initial ice formation and thicknesses along the shores of Foxe Basin, Southampton Island, western Hudson Bay and southern Baffin Island were near normal in October. However, by mid-late November the southward advance of the ice edge from Foxe Basin into Hudson Bay and Hudson Strait, and from Davis Strait around the south coast of Baffin Island, was showing a delay of about a week due to the above normal air temperatures. In December, areas of delayed ice advance continued to exist in southwestern Hudson Bay, in Hudson Strait, in Frobisher Bay, along the leading edge of the Davis Strait ice pack and along the Labrador coast. The progression of ice formation was most delayed along the Labrador coast, where by the end of December it was approximately 3 weeks behind normal. However, in southeastern Hudson Bay and in Ungava Bay, areas of greater than normal ice concentrations developed in early December and persisted throughout most of the month.        

Freeze-up: October to December

Following the summer melt season, at the beginning of October, all parts of the region were free of sea ice.  Freeze-up then began normally and by mid-October new ice had begun forming along northern coastal areas of Foxe Basin. However, due to the warmer than normal average air temperatures, the progress of ice thickening and southward advance then slowed to approximately a week behind normal. By early November, new and grey ice covered the northern third of Foxe Basin and extended southwards along its coasts. New and grey ice had also developed in Roes Welcome Sound, along the south coast of Southampton Island, along the west coasts of Hudson and James Bays, along portions of the coasts of eastern Hudson Bay and western Ungava Bay, and at the heads of Frobisher Bay and Cumberland Sound.  By mid-November, Foxe Basin was nearly 100% ice covered, 1 week later than normal, as was Cumberland Sound, 1 week earlier than normal.
By the beginning of December, Foxe Basin was filled with predominantly grey-white ice when normally thin first-year ice would have already prevailed in this area and the coastal fast ice in Foxe Basin was less extensive than normal. Measured ice thicknesses at Hall Beach were running 6-7cm below those estimated based on the air temperature history during freeze-up at this time. Coastal fast ice had also begun to develop along the coasts of southern Baffin Island, Southampton Island, Hudson Bay, western James Bay and western Ungava Bay. Measured ice thicknesses at Coral Harbour were running approximately 4 cm less than predicted. The pack ice from Davis Strait had rounded southern Baffin Island as per normal, and grey-white ice filled Cumberland Sound. New and grey-white ice filled Frobisher Bay. Grey-white ice was forming in the northern part of Hudson Bay while new and grey ice lined its western shore, the southern margin of the main pack, and the shores of James Bay, Hudson Strait and Ungava Bay. New ice was forming in the fiords of the Labrador coast and in Lake Melville. The pattern of ice advance was close to normal everywhere, although slightly less extensive than normal in southwestern Hudson Bay, in western Hudson Strait, in Frobisher Bay and along the eastward margin of the Davis Strait pack ice. On the other hand, ice extents were slightly more extensive than normal in east-central Hudson Bay. By mid-December, thin first-year ice finally prevailed in Foxe Basin, 1-2 weeks behind schedule, and was developing in the northern part of Hudson Bay, in the Davis Strait pack ice, and along the shores of Cumberland Sound. Ice concentrations were less than normal along the Labrador coast and greater than normal in eastern Hudson Strait and Ungava Bay, primarily because winds in December averaged from the east and served to compress the ice westwards from the Labrador Sea into Hudson Strait. Ice concentrations were also greater than normal in southeastern Hudson Bay. Fast ice formation within the coastal fiords of Labrador finally began in the third week of December.

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