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1 Canadian Ice Service Key Points and Details concerning the 2009 Arctic Minimum Summer Sea Ice Extent October 1 st,

2 Key Points of Interest Arctic-wide The Arctic-wide minimum sea ice extent at the end of August 2009 was similar to that of 2008 (i.e. slightly greater than the record minimum set in 2007), but the spatial distribution of the ice was different. There was more ice in the southern Beaufort Sea than in 2008, but there was less ice in the Laptev Sea than in Although still well below the year normal extent of 6.6 million square kilometers, the minimum Arctic sea ice extent at the end of the 2009 summer melt season (~5.1 million square kilometers achieved on September 12 th ) is slightly greater than that in 2008 (4.7 million square kilometers). Since both the 2008 and 2009 ice coverages exceeded that of 2007 (4.3 million square kilometers), it is possible that the record minimum conditions that occurred in 2007 may have been more of an extreme variation about a smaller negative trend as opposed to a significant acceleration in Arctic sea ice loss. Canada In the western Canadian Arctic, ice concentrations at the end of August were near to slightly below normal. Greater than normal concentrations of ice occurred in the south-eastern Beaufort Sea due to periods of northerly winds, which carried some of the multi-year pack ice southwards into this area during the melt season. In the Northwest Passage, ice concentrations were near to greater than normal in western sections, near normal in central sections, and less than normal in eastern sections. Greater than normal concentrations of ice in the central and western parts of the Northwest Passage in July and August led to a delay in navigability of the southern route, while the northern route did not become truly navigable at all this year. This situation is similar to 2006, a year in which the southern route was passable but the northern route remained clogged with ice. By contrast, both routes were navigable in the summers of 2007 and In the eastern Canadian Arctic, ice concentrations were for the most part well below normal (although they did not set a record). This was due to an early clearing of Nares Strait, northern Baffin Bay and Lancaster Sound. In Hudson Bay, greater than normal concentrations of ice (due to colder than normal air temperatures in June, July and August) lingered in the southern sections until the end of August, when normally the area would have been clear of ice by mid-august. In the farthest north of Canada, along the north coast of Ellesmere Island, there were no further losses to the ice shelves and no new ice islands. This is primarily because no open water lead developed this year between the coast of Ellesmere Island and the pack ice in the Arctic Ocean. 2

3 Table of Contents 1. The Arctic Ocean... 4 Background: Summers of 2007 and CIS Outlook for End-of-Melt-Season 2009 Arctic Sea Ice Conditions (Verification of CIS Outlook) The Canadian Arctic: end-of-melt-season 2009 details... 8 Western Arctic: General... 8 Western Arctic: Beaufort Sea... 9 Northwest Passage Eastern Arctic: General Eastern Arctic: Nares Strait Eastern Arctic: Lancaster Sound and northern Baffin Bay Eastern Arctic: Davis Strait Eastern Arctic: Petermann Ice Island Northern Ellesmere Ice Shelves and Ice Islands Hudson Bay

4 1. The Arctic Ocean Background: Summers of 2007 and 2008 The Arctic summer minimum sea ice extent observed in September 2007 (4.3 million square kilometers) broke all records (note that most records span only years) and was well below all model predictions. As a result, scientists speculated at the time that the observed negative trend in Arctic summer sea ice extent could be accelerating. The minimum Arctic sea ice extent in September, 2008 (4.7 million square kilometers), however, was slightly greater than that of 2007, as a result of a large area of first-year ice situated over the North Pole that did not melt as anticipated (although overall summer sea ice thicknesses were less in 2008 than in 2007). CIS Outlook for 2009 Due to the uncertainties introduced by the summers of 2007 and 2008 regarding any possible acceleration in the trend, in June, 2009, the Canadian Ice Service forecast a 2009 Arctic minimum sea ice extent of 5 million square kilometers (similar to but slightly greater than that of 2008). This value was based on: 1) the amount of thick multi-year ice remaining in the Arctic Ocean at the end of May 2009, which was similar to, but slightly less than, the amount remaining at the end of May 2008; 2) the fact that many areas of the Canadian Arctic experienced greater than normal ice concentrations and thicknesses during the winter of ; and 3) the fact that a large area of first-year ice did not melt as predicted over the north pole in the 2008 melt season. 4

End-of-Melt-Season 2009 Arctic Sea Ice Conditions (Verification of CIS Outlook) The Arctic-wide minimum sea ice extent at mid-september 2009 was similar to that of 2008 (i.e. slightly greater than the record minimum set in 2007), but the spatial distribution of the ice was different.

5 End-of-Melt-Season 2009 Arctic Sea Ice Conditions (Verification of CIS Outlook) The Arctic-wide minimum sea ice extent at mid-september 2009 was similar to that of 2008 (i.e. slightly greater than the record minimum set in 2007), but the spatial distribution of the ice was different. There was more ice in the southern Beaufort Sea and the East Greenland waters than in 2008, but there was less ice in the Laptev Sea than in Figure 1. Ice concentration chart produced at CIS using a combination of AMSR-E satellite imagery and ice chart data. Periods of northerly winds drove the multi-year pack ice southwards into the southeastern Beaufort Sea during the melt season, leading to greater than normal concentrations in this area this summer (in 2009). 5

6 Although still well below the year normal extent of 6.6 million square kilometers, the minimum Arctic sea ice extent at the end of the 2009 summer melt season (~5.1 million square kilometers) is slightly greater than that in 2008 (4.7 million square kilometers). Since both the 2008 and 2009 ice coverages exceeded that of 2007 (4.3 million square kilometers), it is possible that the record minimum conditions that occurred in 2007 may have been more of an extreme variation about a smaller negative trend as opposed to a significant acceleration in Arctic sea ice loss. Year / Month August September Table 1. Arctic sea ice extent based on monthly data from NSIDC. Ice extents are in millions of square kilometers. Figure 2. Trend in NSIDC September sea ice extent anomalies showing 2009 > 2008 > 2007 (Figure taken from the NSIDC web page data derived from Nimbus-7 SSMR and DMSP SSM/I Passive Microwave Data sets). 6

7 Figure 3. NSIDC sea ice extent (as of 30 Sept. 2009) derived from Nimbus-7 SSMR and DMSP SSM/I Passive Microwave Data. Figure 4. CIS sea ice extent derived using a combination of AMSR-E satellite imagery and ice chart data. 7

2. The Canadian Arctic: end-of-melt-season 2009 details Western Arctic: General Ice concentrations in the western Canadian Arctic in the 3 rd week of September, 2009, were near to

8 2. The Canadian Arctic: end-of-melt-season 2009 details Western Arctic: General Ice concentrations in the western Canadian Arctic in the 3 rd week of September, 2009, were near to slightly below the normal. Figure 5. Bar graph showing ice coverages for the date of September 24, for the years of 1968 to the present (2009), in the western Canadian Arctic. 8

Western Arctic: Beaufort Sea In 2009, the Beaufort Sea ice coverage for early-september was greater than that observed in 2007 and 2008.

9 Western Arctic: Beaufort Sea In 2009, the Beaufort Sea ice coverage for early-september was greater than that observed in 2007 and Periods of northerly winds drove the multi-year pack ice southwards into the southeastern Beaufort Sea during the 2009 melt season, leading to greater than normal concentrations in parts of this area. Note that while 2007 was a record minimum ice coverage year for the whole Arctic, it was not a record year for the Canadian Arctic. For the Beaufort Sea, 2008 represented the new record year, breaking the old record set in Figure 6. Bar graph showing ice coverages for the date of September 24, for the years of 1968 to the present (2009), in the Beaufort Sea. 9

10 Figure 7. Ice concentrations at mid-september, 2009, were greater than normal in southeastern parts of the Beaufort Sea, due to periods of northerly winds, which carried some of the remaining multi-year pack ice southwards into this area during the melt season. 10

Northwest Passage In the Northwest Passage, ice concentrations were near to greater than normal in western sections, near normal in central sections, and less than normal in eastern sections.

11 Northwest Passage In the Northwest Passage, ice concentrations were near to greater than normal in western sections, near normal in central sections, and less than normal in eastern sections. Greater than normal concentrations of ice in the central and western parts of the Northwest Passage in July and August led to a delay in navigability of the southern route, while the northern route did not become navigable at all in This situation is similar to 2006, a year in which the southern route was passable but the northern route remained clogged with ice. By contrast, both routes were navigable in the summers of 2007 and Figure 8. Average total accumulated ice coverage along the entire length of the Northwest Passage (southern route) for the period of May 14 to September 24, for the years 1968 to

The consolidation of the ice in Amundsen Gulf over the past winter, along with colder than normal air temperatures in June and July, led to a delay in ice melt in the western part of the southern

12 The consolidation of the ice in Amundsen Gulf over the past winter, along with colder than normal air temperatures in June and July, led to a delay in ice melt in the western part of the southern route of the Northwest Passage. Figure 9. Colder than normal air temperatures in June and July contributed to a delay in ice melt in the southern route of the Northwest Passage this year (2009). In the Beaufort Sea, northerly winds pushed the multi-year ice pack southwards during the melt season, creating areas of greater than normal ice concentrations (where blue denotes greater than normal concentrations on CIS charts and red denotes less). 12

The influx of Arctic multi-year ice into the passages between the Canadian Arctic Archipelago last summer (2008) led to the blockage of Viscount Melville Sound and M Clintock Channel this summer

13 The influx of Arctic multi-year ice into the passages between the Canadian Arctic Archipelago last summer (2008) led to the blockage of Viscount Melville Sound and M Clintock Channel this summer (2009). As a result, the northern route of the Northwest Passage was not navigable and the central part of the southern route (Larsen Sound) had limited navigability due to the presence of multi-year ice and an associated delay in the melt of the first-year ice in the area. Figure 10. Left: CIS ice charts for the first week of December, 2008 (top: coloured for concentration, where red indicates mobile ice and grey indicates consolidated or fast ice; bottom: coloured for ice type, where red-brown indicates multi-year ice and green indicates first-year ice). Right: Ice chart showing the departure-from-median concentration of old ice in August, 2009 (where blue indicates greater than normal concentrations and red indicates less). 13

14 Figure 11. Ice concentration chart produced at CIS using a combination of AMSR-E satellite imagery and ice chart data, showing ice conditions in the Northwest Passage at the end of August. The northern and southern routes of the Northwest Passage are indicated in pink. 14

Eastern Arctic: General In the eastern Canadian Arctic, ice concentrations in early September were for the most part well below the 1971-2000 normal (although they did not set a record).

15 Eastern Arctic: General In the eastern Canadian Arctic, ice concentrations in early September were for the most part well below the normal (although they did not set a record). This was due to an early clearing of Nares Strait, northern Baffin Bay and Lancaster Sound. Figure 12. Bar graph showing yearly ice coverage for the date of September 24, from 1968 to the present (2009), in the eastern Canadian Arctic. 15

Eastern Arctic: Nares Strait An anomalous, persistent ice arch at the north end of Nares Strait developed in February (as a result of high ice pressures / shoreward ice convergence in the Lincoln

16 Eastern Arctic: Nares Strait An anomalous, persistent ice arch at the north end of Nares Strait developed in February (as a result of high ice pressures / shoreward ice convergence in the Lincoln Sea) and broke in July. Along with persistent northerly winds, this created polynya-like conditions along the entire length of the Strait throughout the winter months. That is, the Strait did not consolidate as per normal. As a result, ice clearing in this area was much earlier than normal. Nares Strait became ice free in May, except for areas of shore-fast ice in adjoining bays and fiords, and remained so until mid-july when the ice arch finally broke, allowing multi-year ice from the Arctic to invade the strait once again. Once the ice arch broke in July, the influx of Arctic multi-year ice led to greater than normal ice concentrations in the Strait during the rest of the summer. Figure 13. Modis image for June 26, 2009, showing an ice-free Nares Strait. A well-defined ice arch can be seen indenting into to Arctic multi-year ice pack in the Lincoln Sea at its northern end. A large piece of freshly broken-off shore-fast sea ice, originally attached to the front of the Petermann Glacier, is circled in pink. 16

$Modis image for July 17, 2009, showing the initial influx of Arctic multi-year ice into Nares Strait, after the fracture of$

17 Figure 14. Modis image for July 17, 2009, showing the initial influx of Arctic multi-year ice into Nares Strait, after the fracture of the ice arch at its northern end. Fracturing of the arch began July 6, and ice began to enter the strait on July

18 Figure 15. Meris image (copyright ESA, 2009) for August 04, 2009, showing extensive Arctic multi-year ice amounts in Nares Strait. 18

19 Figure 16. Departure from normal concentration ice charts showing: a) less than normal total ice concentrations in June in Nares Strait; and b) greater than normal old ice concentrations in August. 19

20 Additional facts: o Normally, the ice in Nares Strait consolidates between February and July (based on ) CIS ice chart data), blocking the flow of Arctic Multi-year ice (MYI) into Baffin Bay and the North Atlantic for half the year. This allows for the formation of the North Open Water polynya at the southern end of the Strait, an area of thin ice and/or open water that is biologically important to many species. o 2009 is only the second year in the CIS ice chart record in which Nares Strait did not consolidate (the other year being 2007). o In 2007, however, no permanent ice arch formed at the north end of the Strait and this led to anomalously greater-than-normal amounts of thick, multi-year ice flowing from the Arctic Ocean into Baffin Bay throughout the winter months (some of which eventually reached Newfoundland waters in April of that year). o In 2009, a permanent ice arch formed at the north end of the Strait in the Lincoln Sea, blocking the flow of multi-year ice from the Arctic Ocean into Baffin Bay and allowing for the formation of a latent-heat type polynya along the whole length of the strait in the winter, leading to the early clearing of all ice in May. 20

Eastern Arctic: Lancaster Sound and northern Baffin Bay This year (2009), the ice in Lancaster Sound and northern Baffin Bay broke up and cleared at around the end of May / beginning of June.

21 Eastern Arctic: Lancaster Sound and northern Baffin Bay This year (2009), the ice in Lancaster Sound and northern Baffin Bay broke up and cleared at around the end of May / beginning of June. Normal break-up dates (according to the CIS Climatological Sea Ice Atlas for Northern Waters) are between June 18 and July 16 for the eastern and western parts of Lancaster Sound, respectively. Normal break-up / clearing dates for northern Baffin Bay are near July 02. The early clearing of these areas was related to the fact that neither Lancaster Sound nor Nares Strait ice consolidated this past winter. While this was very unusual for Nares Strait, it is not particularly unusual for the ice in Lancaster Sound to remain mobile throughout some winters. Persistent northerly winds over Nares Strait throughout the winter/spring period and a period of strong northwesterly winds over western parts of Lancaster Sound in May then helped to clear these areas of ice 3-6 weeks earlier than normal. Figure 17. Left: Departure from normal ice concentration chart for June, 2009, showing the early clearing of ice for Lancaster Sound and northern Baffin Bay (areas in blue circles). Right: NCEP/NCAR vector wind anomaly plot for May, 2009, showing stronger than normal northwesterly winds in eastern Barrow Strait and western Lancaster Sound. 21

22 Eastern Arctic: Davis Strait Greater than normal concentrations of ice lingered in Davis Strait well into August, this year. Air temperatures were near to greater than normal in this area in June and July and probably did not play a role in maintaining the anomalous ice conditions in this area. Sea surface salinities, on the other hand, were below normal, as were sea surface temperatures. Fresher (and therefore less dense) surface waters restrict the mixing of colder surface waters with warmer waters beneath. Restricted vertical mixing of sea water, due to fresher surface waters, therefore likely: 1) promoted some additional ice growth during the March to May period in this area, when air temperatures were still below freezing; and 2) helped maintain colder sea surface temperatures into the beginning of the melt season, slowing the ice melt in the area. Figure 18. Bar graph of ice coverage for the Davis Strait region for the date of August 13, over the period of 1971 to Ice coverage on August 13, 2009, was greater than it was for that same date over the previous 13 years. 22

23 Figure 19. Departure from normal concentration sea ice charts for various weeks spanning March to August, 2009, showing greater than normal ice concentrations in the Davis Strait area (red-circled areas). 23

Figure 20. NCEP/NCAR reanalysis surface air temperature anomaly for June/July/August 2009.

24 Figure 20. NCEP/NCAR reanalysis surface air temperature anomaly for June/July/August Figure 21. Air temperature reported at Iqaluit for the period of June 01 to August 31,

25 Figure 22. A vertical salinity profile for southern Davis Strait area recorded by an ARGO buoy for August 19, 2009 (green line) plotted against a climatological salinity profile for the area (blue line). Surface salinities in 2009 (32.65 PSU) are currently less than the climatological normal for this area (~33.00 PSU). 25

Eastern Arctic: Petermann Ice Island The Petermann Ice Island, a large tabular iceberg that broke off the Petermann Glacier in northern Greenland in July, 2008, drifted southwards to reach the mouth

26 Eastern Arctic: Petermann Ice Island The Petermann Ice Island, a large tabular iceberg that broke off the Petermann Glacier in northern Greenland in July, 2008, drifted southwards to reach the mouth of Frobisher Bay by June, It then disintegrated into numerous small fragments. Figure 23. Left: The track of the Petermann Ice Island (determined from satellite imagery and via a tracking beacon deployed on the ice island). Right: Observed positions and a picture of some of the numerous ice island fragments seen at the mouth of Frobisher Bay following the break-up of the Ice Island. 26

Northern Ellesmere Ice Shelves and Ice Islands No further losses to the northern Ellesmere Island ice shelves occurred in 2009, and no new ice islands were created.

27 Northern Ellesmere Ice Shelves and Ice Islands No further losses to the northern Ellesmere Island ice shelves occurred in 2009, and no new ice islands were created. This is probably related to the fact that no period of persistent offshore winds developed in 2009 and, as a result, no open water lead developed between the Ellesmere Island coast and the Arctic pack ice this year. June to August surface air temperatures were 1ºC to 2.5 ºC above normal (similar to 2008). The leading edge of the Beaufort Sea ice island pack, created during July and August, 2008, from the break-up of the northern Ellesmere Ice Shelves, now reaches south of 80ºN to Borden Island. Some of the ice islands have also entered the Canadian Arctic Archipelago via the Sverdrup and Peary Channels. The remains of the 2005 Ayles Ice Island, now in at least 4 fragments if not more, are mostly located in Penny Strait and Queens Channel, although one remains to the east or southeast of Amund Ringnes Island. Figure 24. Pink circle: location of the Ellesmere Island ice shelves. White circle: current distribution of the 2005 and 2008 ice islands. 27

28 Figure 25. June to August, 2009, surface air temperature anomalies over Ellesmere Island (from NCEP/NCAR reanalysis data). The Eureka weather station established record-breaking temperature anomalies in July and August of Figure 26. Bar chart showing the number of weeks an open water lead existed between the northern Ellesmere Island coast and the Arctic pack ice, for the summers of 1997 to

Hudson Bay In Hudson Bay, greater than normal concentrations of ice lingered in the southern sections until the end of August (3-4 weeks later than normal).

29 Hudson Bay In Hudson Bay, greater than normal concentrations of ice lingered in the southern sections until the end of August (3-4 weeks later than normal). Normally the area would have been clear of ice by mid-august. The persistence of the ice was related to colder than normal air temperatures and cloudier-than-normal skies (less sun means less melt) in June, July and August. The frequency of presence of sea ice in this area at the end of August is normally less than 15%. Figure 27. Bar graph showing the total accumulated ice coverage for central and southwestern Hudson Bay, for the period May 14 to September 03, for the years 1971 to

30 Figure 28. Departure from normal ice concentrations in Hudson Bay on August 10,

Figure 29. Top: A series of CIS weekly regional ice charts showing anomalous ice patches in southern Hudson Bay throughout August, 2009.

31 Figure 29. Top: A series of CIS weekly regional ice charts showing anomalous ice patches in southern Hudson Bay throughout August, Bottom: A median ice concentration chart for the week of August 13 (taken from the CIS Climatological Sea Ice Atlas for northern waters) showing no ice in this area in the middle of August. 31

32 Figure 30. NCEP/NCAR reanalysis data showing colder than normal air temperatures and cloudier than normal skies over southern Hudson Bay for the period June-August,

APPENDIX B PHYSICAL BASELINE STUDY: NORTHEAST BAFFIN BAY 1

APPENDIX B PHYSICAL BASELINE STUDY: NORTHEAST BAFFIN BAY 1 1 By David B. Fissel, Mar Martínez de Saavedra Álvarez, and Randy C. Kerr, ASL Environmental Sciences Inc. (Feb. 2012) West Greenland Seismic