Sea ice in Canada
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Sea ice is a prominent feature in the Northern Canadian Waters.Footnote 1 It consists of seasonal ice that forms and melts each year (referred to as first-year ice) and ice that is present all-year round (referred to as multi-year ice). The amount and type of sea ice present, and the total minimum area it covers during the summer season,Footnote 2 impacts human activity and biological habitat.
Sea ice
National sea ice
Key results
- In 2020, the sea ice area in the Northern Canadian Waters reached 1.04 million square kilometres (km2), representing 27.6% of the total area
- The lowest sea ice area occurred in 2012, with 0.70 million km2
- Between 1968 and 2020, summer sea ice area in the Northern Canadian Waters declined at a rate of 7.5% per decade
Average sea ice area, Northern Canadian Waters, 1968 to 2020

Data table for the long description
Year | Northern Canadian Waters (millions of square kilometres) |
---|---|
1968 | 1.26 |
1969 | 1.59 |
1970 | 1.46 |
1971 | 1.37 |
1972 | 1.66 |
1973 | 1.33 |
1974 | 1.45 |
1975 | 1.31 |
1976 | 1.46 |
1977 | 1.27 |
1978 | 1.67 |
1979 | 1.43 |
1980 | 1.40 |
1981 | 1.17 |
1982 | 1.35 |
1983 | 1.60 |
1984 | 1.47 |
1985 | 1.35 |
1986 | 1.54 |
1987 | 1.39 |
1988 | 1.26 |
1989 | 1.40 |
1990 | 1.40 |
1991 | 1.43 |
1992 | 1.63 |
1993 | 1.30 |
1994 | 1.36 |
1995 | 1.20 |
1996 | 1.51 |
1997 | 1.26 |
1998 | 0.85 |
1999 | 1.11 |
2000 | 1.24 |
2001 | 1.23 |
2002 | 1.27 |
2003 | 1.19 |
2004 | 1.37 |
2005 | 1.17 |
2006 | 0.99 |
2007 | 0.93 |
2008 | 0.90 |
2009 | 1.14 |
2010 | 0.83 |
2011 | 0.74 |
2012 | 0.70 |
2013 | 1.12 |
2014 | 1.04 |
2015 | 1.11 |
2016 | 0.79 |
2017 | 0.94 |
2018 | 1.23 |
2019 | 0.82 |
2020 | 1.04 |
Note: Sea ice area is measured during the summer season. For the Northern Canadian Waters, the summer season is defined as the period from June 19 to November 19 for the Hudson Bay domain and from June 25 to October 15 for the Canadian Arctic domain.
Download data file (Excel/CSV; 1.25 kB)
How this indicator was calculated
Note: A statistically significant trend is reported when the Mann-Kendall test indicates the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
Sea ice area decline in the Northern Canadian Waters is the result of a combination of factors. Human-induced warming from greenhouse gas emissions and climate variability has resulted in an unprecedented loss of sea ice over the last 50 years.
Arctic sea ice is very sensitive to climate change because of the sea ice-albedo feedback that influences how much solar radiation is absorbed into the sea ice-ocean system. As sea ice area declines due to warming temperatures, more dark ocean surfaces that readily absorb sunlight (solar radiation) are exposed, in turn causing more sea ice to melt. This feedback cycle is an important factor in amplifying Arctic temperatures. Research has shown that the loss of Arctic sea ice is a very significant contributor to the recent amplification of Arctic temperature change compared to the global average.
Changes in the amount of sea ice, the location of ice edges and the timing of seasonal ice formation and melt have complex, cascading ecosystem impacts. Sea ice declines result in a loss of wildlife habitat, as it serves as hunting platforms for polar bears and as resting grounds and nursery areas for walruses and seals. Algae that grow on the underside of sea ice are also important to the marine food supply.
These changes also have an impact on the safety of northerners who use sea ice as a transportation route or platform for hunting and fishing. More than ever, decisions on whether to go out on the ice must be made on the basis of weather and sea ice condition reports, as northerners can no longer rely on traditional knowledge of when it is safe to venture out on the ice.
Regional sea ice
In the Northern Canadian Waters, the summer sea ice area varies by sub-region. Five (5) sub-regions make up the Canadian Arctic domain (Kane Basin, Foxe Basin, Baffin Bay, the Beaufort Sea and the Canadian Arctic Archipelago) and 4 sub-regions comprise the Hudson Bay domain (Hudson Bay, Hudson Strait, Davis Strait and the Northern Labrador Sea).
Key results
- The Canadian Arctic Archipelago, Beaufort Sea and Kane Basin sub-regions usually remain covered by ice in the summer because they contain a mix of multi-year and first-year ice
- The 4 sub-regions of the Hudson Bay domain (Hudson Bay, Hudson Strait, Davis Strait and Northern Labrador Sea) are typically free of sea ice in summer because they are first-year ice regions
- All sub-regions exhibit statistically significant decreasing trends in summer sea ice area over the 1968 to 2020 period, ranging from a 3.7% decrease per decade in the Kane Basin to a 15.3% decrease per decade in the Northern Labrador Sea
Sub-region sea ice area trends, Northern Canadian Waters, 1968 to 2020

Data table for the long description
Year | Foxe Basin (thousands of square kilometres) |
Kane Basin (thousands of square kilometres) |
Baffin Bay (thousands of square kilometres) |
Beaufort Sea (thousands of square kilometres) |
Canadian Arctic Archipelago (thousands of square kilometres) |
Hudson Bay (thousands of square kilometres) |
Hudson Strait (thousands of square kilometres) |
Davis Strait (thousands of square kilometres) |
North Labrador Sea (thousands of square kilometres) |
---|---|---|---|---|---|---|---|---|---|
1968 | 73 | 26 | 130 | 337 | 551 | 94 | 21 | 25 | 5 |
1969 | 79 | 35 | 168 | 486 | 569 | 191 | 25 | 34 | 5 |
1970 | 71 | 31 | 196 | 392 | 570 | 130 | 19 | 38 | 12 |
1971 | 69 | 32 | 171 | 402 | 512 | 109 | 30 | 31 | 9 |
1972 | 114 | 33 | 160 | 355 | 659 | 211 | 42 | 67 | 15 |
1973 | 62 | 35 | 137 | 372 | 520 | 123 | 30 | 46 | 5 |
1974 | 52 | 33 | 100 | 485 | 570 | 154 | 27 | 24 | 7 |
1975 | 52 | 34 | 80 | 479 | 509 | 107 | 16 | 25 | 8 |
1976 | 76 | 34 | 136 | 449 | 593 | 111 | 18 | 38 | 7 |
1977 | 71 | 35 | 209 | 298 | 514 | 84 | 15 | 41 | 6 |
1978 | 106 | 30 | 208 | 422 | 646 | 191 | 29 | 34 | 7 |
1979 | 75 | 33 | 139 | 337 | 657 | 127 | 22 | 36 | 6 |
1980 | 60 | 32 | 146 | 433 | 575 | 108 | 15 | 25 | 2 |
1981 | 40 | 30 | 125 | 367 | 465 | 103 | 14 | 27 | 2 |
1982 | 61 | 31 | 157 | 314 | 557 | 140 | 24 | 57 | 6 |
1983 | 88 | 35 | 185 | 476 | 532 | 158 | 36 | 81 | 12 |
1984 | 64 | 31 | 123 | 455 | 525 | 161 | 42 | 56 | 14 |
1985 | 55 | 30 | 84 | 480 | 511 | 133 | 27 | 24 | 10 |
1986 | 72 | 32 | 178 | 407 | 620 | 163 | 21 | 42 | 3 |
1987 | 84 | 26 | 186 | 288 | 583 | 155 | 26 | 32 | 7 |
1988 | 64 | 24 | 120 | 403 | 487 | 109 | 21 | 25 | 5 |
1989 | 78 | 31 | 174 | 398 | 526 | 139 | 19 | 28 | 5 |
1990 | 77 | 23 | 143 | 382 | 579 | 125 | 29 | 35 | 7 |
1991 | 68 | 30 | 103 | 483 | 550 | 120 | 27 | 33 | 12 |
1992 | 79 | 38 | 140 | 466 | 608 | 208 | 31 | 53 | 6 |
1993 | 67 | 31 | 210 | 261 | 524 | 141 | 21 | 41 | 4 |
1994 | 56 | 29 | 140 | 454 | 510 | 116 | 19 | 31 | 6 |
1995 | 56 | 25 | 169 | 299 | 529 | 94 | 12 | 14 | 0 |
1996 | 61 | 35 | 258 | 446 | 536 | 119 | 21 | 28 | 6 |
1997 | 47 | 35 | 156 | 319 | 570 | 101 | 15 | 16 | 3 |
1998 | 52 | 32 | 138 | 166 | 391 | 53 | 9 | 11 | 1 |
1999 | 57 | 30 | 143 | 344 | 457 | 36 | 8 | 26 | 5 |
2000 | 41 | 32 | 91 | 420 | 502 | 119 | 10 | 25 | 3 |
2001 | 56 | 34 | 102 | 442 | 519 | 50 | 5 | 17 | 1 |
2002 | 57 | 34 | 77 | 368 | 562 | 122 | 14 | 26 | 9 |
2003 | 51 | 30 | 73 | 357 | 553 | 97 | 8 | 17 | 2 |
2004 | 60 | 32 | 101 | 320 | 596 | 213 | 20 | 24 | 1 |
2005 | 40 | 30 | 111 | 359 | 548 | 63 | 10 | 9 | 1 |
2006 | 27 | 27 | 61 | 376 | 432 | 46 | 4 | 12 | 1 |
2007 | 54 | 24 | 96 | 244 | 407 | 76 | 10 | 18 | 5 |
2008 | 59 | 25 | 91 | 163 | 435 | 93 | 14 | 23 | 0 |
2009 | 52 | 19 | 69 | 313 | 504 | 137 | 16 | 28 | 6 |
2010 | 39 | 26 | 79 | 237 | 406 | 34 | 3 | 8 | 0 |
2011 | 44 | 22 | 73 | 192 | 337 | 59 | 3 | 6 | 0 |
2012 | 51 | 26 | 43 | 135 | 351 | 73 | 6 | 18 | 0 |
2013 | 57 | 32 | 67 | 347 | 501 | 84 | 9 | 17 | 5 |
2014 | 60 | 22 | 52 | 268 | 519 | 86 | 12 | 13 | 5 |
2015 | 65 | 32 | 127 | 265 | 417 | 139 | 17 | 43 | 3 |
2016 | 42 | 27 | 57 | 149 | 399 | 79 | 12 | 22 | 2 |
2017 | 43 | 28 | 96 | 199 | 472 | 61 | 9 | 36 | 0 |
2018 | 59 | 32 | 98 | 333 | 533 | 123 | 17 | 33 | 4 |
2019 | 29 | 20 | 47 | 162 | 424 | 112 | 7 | 17 | 1 |
2020 | 48 | 26 | 56 | 313 | 445 | 108 | 12 | 24 | 4 |
1968 to 2020 decadal trend | -7.5% | -3.7% | -12.1% | -8.3% | -4.4% | -8.5% | -13.6% | -10.6% | -15.3% |
Note: Sea ice area is measured during the summer season. For the Northern Canadian Waters, the summer season is defined as the period from June 19 to November 19 for the Hudson Bay domain and from June 25 to October 15 for the Canadian Arctic domain.
Download data file (Excel/CSV; 3.01 kB)
How this indicator was calculated
Note: A statistically significant trend is reported when the Mann-Kendall test indicates the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
In absolute terms, the largest summer sea ice area loss over the 1968 to 2020 period has occurred in the Beaufort Sea sub-region, where approximately 204 000 km2 of sea ice was lost (which corresponds to almost 3 times the land area of New Brunswick). The Canadian Arctic Archipelago, Baffin Bay and Hudson Bay sub-regions also lost a large amount of sea ice area over the same period, of approximately 137 000 km2, 110 000 km2 and 64 000 km2, respectively.
Each year, the minimum sea ice area is observed during the month of September. At this time of the year, all the sea ice in the Hudson Bay domain has melted. The Canadian Arctic domain’s sub-regions present statistically significant decreasing trends in average September sea ice area over the 1968 to 2020 period, except for the Kane Basin where no statistically significant trend was reported. In the Canadian Arctic, a decrease of 9.4% per decade has been observed for the September sea ice area, which is lower than the 13.1% decadal decrease observed for the entire Arctic.Footnote 3Footnote 4
Sub-region September sea ice area decadal trends, Canadian Arctic domain, 1968 to 2020

Data table for the long description
Year | Foxe Basin (thousands of square kilometres) |
Kane Basin (thousands of square kilometres) |
Baffin Bay (thousands of square kilometres) |
Beaufort Sea (thousands of square kilometres) |
Canadian Arctic Archipelago (thousands of square kilometres) |
Canadian Arctic domain (thousands of square kilometres) |
---|---|---|---|---|---|---|
1968 | 31 | 19 | 31 | 273 | 455 | 809 |
1969 | 13 | 31 | 66 | 474 | 437 | 1021 |
1970 | 22 | 26 | 76 | 341 | 428 | 892 |
1971 | 10 | 32 | 30 | 342 | 329 | 743 |
1972 | 60 | 31 | 67 | 255 | 568 | 981 |
1973 | 16 | 34 | 29 | 276 | 373 | 728 |
1974 | 8 | 30 | 10 | 416 | 414 | 878 |
1975 | 1 | 33 | 17 | 512 | 396 | 959 |
1976 | 30 | 30 | 17 | 376 | 464 | 917 |
1977 | 21 | 37 | 73 | 200 | 403 | 734 |
1978 | 53 | 28 | 50 | 294 | 557 | 982 |
1979 | 19 | 29 | 18 | 208 | 545 | 819 |
1980 | 6 | 28 | 7 | 434 | 470 | 945 |
1981 | 0 | 25 | 14 | 289 | 322 | 650 |
1982 | 7 | 33 | 41 | 222 | 414 | 716 |
1983 | 56 | 34 | 57 | 465 | 330 | 941 |
1984 | 10 | 27 | 15 | 393 | 392 | 838 |
1985 | 5 | 31 | 3 | 429 | 334 | 802 |
1986 | 15 | 31 | 34 | 305 | 494 | 879 |
1987 | 41 | 25 | 29 | 254 | 434 | 783 |
1988 | 14 | 20 | 4 | 362 | 390 | 791 |
1989 | 19 | 32 | 26 | 298 | 360 | 735 |
1990 | 28 | 30 | 27 | 316 | 483 | 884 |
1991 | 27 | 24 | 9 | 461 | 394 | 916 |
1992 | 33 | 37 | 37 | 413 | 509 | 1030 |
1993 | 24 | 34 | 91 | 169 | 388 | 707 |
1994 | 5 | 27 | 19 | 383 | 362 | 795 |
1995 | 6 | 26 | 34 | 231 | 456 | 754 |
1996 | 8 | 35 | 107 | 401 | 427 | 977 |
1997 | 3 | 35 | 33 | 206 | 508 | 785 |
1998 | 4 | 35 | 19 | 107 | 171 | 335 |
1999 | 6 | 31 | 41 | 196 | 246 | 521 |
2000 | 1 | 33 | 17 | 273 | 295 | 619 |
2001 | 10 | 32 | 18 | 302 | 374 | 737 |
2002 | 5 | 32 | 14 | 218 | 388 | 657 |
2003 | 1 | 32 | 9 | 274 | 450 | 766 |
2004 | 11 | 30 | 14 | 226 | 488 | 769 |
2005 | 1 | 27 | 11 | 273 | 396 | 709 |
2006 | 0 | 24 | 11 | 270 | 266 | 571 |
2007 | 5 | 22 | 16 | 136 | 218 | 396 |
2008 | 7 | 25 | 12 | 105 | 268 | 417 |
2009 | 1 | 29 | 10 | 249 | 337 | 626 |
2010 | 0 | 29 | 16 | 132 | 240 | 418 |
2011 | 2 | 16 | 4 | 113 | 146 | 282 |
2012 | 5 | 22 | 3 | 19 | 150 | 199 |
2013 | 4 | 36 | 16 | 248 | 362 | 666 |
2014 | 5 | 18 | 4 | 197 | 385 | 608 |
2015 | 11 | 34 | 27 | 103 | 202 | 377 |
2016 | 0 | 26 | 7 | 32 | 238 | 303 |
2017 | 1 | 32 | 18 | 115 | 340 | 505 |
2018 | 11 | 30 | 16 | 222 | 398 | 677 |
2019 | 0 | 13 | 2 | 95 | 260 | 371 |
2020 | 0 | 25 | 4 | 201 | 294 | 525 |
1968 to 2020 decadal trend | -19.2% | No trend | -16.0% | -12.5% | -7.3% | -9.4% |
Download data file (Excel/CSV; 2.38 kB)
How this indicator was calculated
Note: The trends presented correspond to the decadal trend over the period from 1968 to 2020. The September sea ice area trend is calculated based on average sea ice area during the month of September for each year from 1968 to 2020. A statistically significant trend is reported when the Mann-Kendall test indicates the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
Climate projections suggest that a nearly sea ice-free summer is possible for the Arctic Ocean by the middle of the 21st century, although sea ice may persist longer in the Canadian Arctic Archipelago region.Footnote 5
Multi-year sea ice
National multi-year sea ice
Multi-year sea ice corresponds to ice that has survived at least one summer's melt. Multi-year sea ice contains less salt and is usually thicker than first-year sea ice, making it harder and more difficult for icebreakers to navigate and clear. Considering that the sub-regions from the Hudson Bay domain are first-year ice regions that are free of multi-year ice during summer, the indicators on multi-year sea ice focus on the Canadian Arctic domain.Footnote 6
Key results
In the Canadian Arctic domain:
- Between 1968 and 2020, multi-year ice made up between 26% to 50% of the total sea ice area
- The multi-year sea ice area has declined by 8.3% per decade over the period from 1968 to 2020
- In 2020, the average multi-year sea ice area reached 381 000 square kilometres (km2)
- The lowest multi-year sea ice area occurred in 2012, with 207 000 km2
Average multi-year sea ice area, Canadian Arctic domain, 1968 to 2020

Data table for the long description
Year | Canadian Arctic domain (thousands of square kilometres) |
---|---|
1968 | 591 |
1969 | 648 |
1970 | 615 |
1971 | 628 |
1972 | 518 |
1973 | 667 |
1974 | 520 |
1975 | 653 |
1976 | 648 |
1977 | 512 |
1978 | 555 |
1979 | 633 |
1980 | 681 |
1981 | 492 |
1982 | 369 |
1983 | 583 |
1984 | 532 |
1985 | 502 |
1986 | 542 |
1987 | 561 |
1988 | 589 |
1989 | 545 |
1990 | 619 |
1991 | 676 |
1992 | 687 |
1993 | 606 |
1994 | 603 |
1995 | 501 |
1996 | 666 |
1997 | 620 |
1998 | 392 |
1999 | 335 |
2000 | 421 |
2001 | 577 |
2002 | 486 |
2003 | 516 |
2004 | 542 |
2005 | 557 |
2006 | 499 |
2007 | 370 |
2008 | 257 |
2009 | 351 |
2010 | 345 |
2011 | 252 |
2012 | 207 |
2013 | 292 |
2014 | 406 |
2015 | 391 |
2016 | 279 |
2017 | 302 |
2018 | 513 |
2019 | 370 |
2020 | 381 |
Note: Multi-year sea ice area is measured during the summer season. For the Canadian Arctic domain, the summer season is defined as the period from June 25 to October 15.
Download data file (Excel/CSV; 1.15 kB)
How this indicator was calculated
Note: A statistically significant trend is reported when the Mann-Kendall test indicated the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
Regional multi-year sea ice
Key results
- In the Canadian Arctic domain, statistically significant decreasing trends in the average multi-year sea ice during the summer season, were found for the Foxe Basin, Kane Basin, Beaufort Sea and Canadian Arctic Archipelago sub-regions
- The Baffin Bay sub-region showed no trend from 1968 to 2020
Sub-region multi-year sea ice area trends, Canadian Arctic domain, 1968 to 2020

Data table for the long description
Year | Foxe Basin (thousands of square kilometres) |
Kane Basin (thousands of square kilometres) |
Baffin Bay (thousands of square kilometres) |
Beaufort Sea (thousands of square kilometres) |
Canadian Arctic Archipelago (thousands of square kilometres) |
---|---|---|---|---|---|
1968 | 1.66 | 8 | 6 | 300 | 276 |
1969 | 0.46 | 17 | 23 | 335 | 273 |
1970 | 0.46 | 16 | 25 | 302 | 272 |
1971 | 0.72 | 22 | 16 | 347 | 243 |
1972 | 4.04 | 20 | 10 | 212 | 272 |
1973 | 0.96 | 25 | 10 | 303 | 329 |
1974 | 0.20 | 14 | 7 | 301 | 198 |
1975 | 0.46 | 16 | 5 | 394 | 237 |
1976 | 2.46 | 18 | 9 | 371 | 248 |
1977 | 0.16 | 14 | 15 | 188 | 294 |
1978 | 4.18 | 15 | 9 | 242 | 285 |
1979 | 5.88 | 15 | 10 | 217 | 385 |
1980 | 0.26 | 18 | 8 | 300 | 355 |
1981 | 0.35 | 16 | 18 | 220 | 237 |
1982 | 0.22 | 11 | 16 | 141 | 200 |
1983 | 3.91 | 20 | 44 | 261 | 254 |
1984 | 0.57 | 14 | 16 | 292 | 210 |
1985 | 0.43 | 13 | 2 | 280 | 206 |
1986 | 1.09 | 11 | 9 | 268 | 252 |
1987 | 0.77 | 13 | 8 | 195 | 345 |
1988 | 0.66 | 10 | 8 | 263 | 308 |
1989 | 0.24 | 17 | 10 | 245 | 273 |
1990 | 0.79 | 17 | 51 | 262 | 288 |
1991 | 1.74 | 6 | 7 | 348 | 313 |
1992 | 1.49 | 28 | 12 | 327 | 318 |
1993 | 1.41 | 24 | 60 | 193 | 327 |
1994 | 3.85 | 20 | 13 | 288 | 278 |
1995 | 0.65 | 17 | 43 | 209 | 232 |
1996 | 0.67 | 19 | 48 | 339 | 259 |
1997 | 0.23 | 22 | 22 | 257 | 319 |
1998 | 0.02 | 18 | 32 | 104 | 239 |
1999 | 0.40 | 13 | 13 | 206 | 102 |
2000 | 0.16 | 15 | 8 | 247 | 150 |
2001 | 0.03 | 17 | 12 | 316 | 232 |
2002 | <0.01 | 18 | 10 | 230 | 228 |
2003 | 0.11 | 14 | 8 | 232 | 263 |
2004 | 0.25 | 18 | 16 | 214 | 293 |
2005 | 0.39 | 14 | 7 | 241 | 295 |
2006 | 0.25 | 13 | 12 | 266 | 208 |
2007 | 0.00 | 13 | 27 | 163 | 167 |
2008 | 0.03 | 12 | 17 | 80 | 149 |
2009 | 0.06 | 9 | 10 | 164 | 168 |
2010 | 0.02 | 14 | 27 | 135 | 169 |
2011 | 0.00 | 12 | 9 | 111 | 120 |
2012 | 0.10 | 13 | 4 | 84 | 106 |
2013 | 0.17 | 12 | 5 | 146 | 129 |
2014 | 0.22 | 11 | 5 | 179 | 212 |
2015 | 0.13 | 15 | 12 | 191 | 172 |
2016 | <0.01 | 15 | 3 | 88 | 173 |
2017 | 0.04 | 16 | 14 | 57 | 215 |
2018 | 0.51 | 17 | 21 | 234 | 241 |
2019 | 0.13 | 13 | 17 | 101 | 239 |
2020 | 0.00 | 10 | 1 | 195 | 175 |
1968 to 2020 decadal trend | -18.9% | -4.6% | No trend | -10.4% | -7.2% |
Note: Multi-year sea ice area is measured during the summer season. For the Canadian Arctic domain, the summer season is defined as the period from June 25 to October 15.
Download data file (Excel/CSV; 2.14 kB)
How this indicator was calculated
Note: A statistically significant trend is reported when the Mann-Kendall test indicated the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
The decrease in average September multi-year sea ice in the Northern Canadian Arctic from 1968 to 2020 is 9.9%. The sub-regions of the Canadian Arctic domain exhibited statistically significant decreasing trends in average September multi-year sea ice area over the 1968 to 2020 period in all regions except Kane Basin.
Sub-region September multi-year sea ice area decadal trends, Canadian Arctic domain, 1968 to 2020

Data table for the long description
Year | Foxe Basin (thousands of square kilometres) |
Kane Basin (thousands of square kilometres) |
Baffin Bay (thousands of square kilometres) |
Beaufort Sea (thousands of square kilometres) |
Canadian Arctic Archipelago (thousands of square kilometres) |
Canadian Arctic domain (thousands of square kilometres) |
---|---|---|---|---|---|---|
1968 | 0.01 | 3 | 6 | 258 | 245 | 513 |
1969 | 0.73 | 17 | 38 | 366 | 262 | 685 |
1970 | 0.04 | 11 | 25 | 283 | 234 | 553 |
1971 | 1.09 | 17 | 11 | 313 | 198 | 540 |
1972 | 0.00 | 18 | 8 | 184 | 208 | 418 |
1973 | 0.61 | 27 | 13 | 259 | 215 | 514 |
1974 | 0.29 | 11 | 6 | 296 | 182 | 495 |
1975 | 0.56 | 18 | 2 | 466 | 190 | 677 |
1976 | 0.22 | 15 | 7 | 356 | 219 | 597 |
1977 | 0.05 | 16 | 21 | 187 | 262 | 486 |
1978 | 0.15 | 11 | 7 | 231 | 250 | 499 |
1979 | 0.39 | 21 | 12 | 178 | 352 | 563 |
1980 | 0.00 | 15 | 3 | 333 | 312 | 662 |
1981 | 0.16 | 12 | 7 | 259 | 205 | 484 |
1982 | 0.08 | 18 | 21 | 131 | 182 | 352 |
1983 | 1.15 | 23 | 45 | 263 | 225 | 557 |
1984 | 1.00 | 15 | 11 | 244 | 183 | 453 |
1985 | 0.00 | 14 | 1 | 282 | 173 | 470 |
1986 | 0.00 | 11 | 6 | 231 | 220 | 468 |
1987 | 0.00 | 10 | 11 | 241 | 311 | 572 |
1988 | 0.29 | 8 | 1 | 267 | 276 | 552 |
1989 | 0.06 | 26 | 17 | 221 | 257 | 521 |
1990 | 0.00 | 23 | 24 | 238 | 257 | 542 |
1991 | 1.95 | 5 | 3 | 373 | 306 | 689 |
1992 | 0.00 | 24 | 17 | 329 | 282 | 651 |
1993 | 0.52 | 31 | 80 | 151 | 279 | 540 |
1994 | 0.04 | 22 | 14 | 302 | 271 | 610 |
1995 | 0.61 | 18 | 19 | 201 | 256 | 494 |
1996 | 0.39 | 21 | 29 | 363 | 280 | 693 |
1997 | 0.33 | 24 | 11 | 185 | 321 | 542 |
1998 | 0.00 | 21 | 13 | 94 | 146 | 273 |
1999 | 0.23 | 13 | 15 | 165 | 107 | 300 |
2000 | 0.00 | 17 | 8 | 210 | 154 | 389 |
2001 | 0.13 | 16 | 10 | 286 | 239 | 551 |
2002 | 0.01 | 14 | 5 | 173 | 224 | 415 |
2003 | 0.02 | 14 | 2 | 224 | 283 | 523 |
2004 | 0.11 | 17 | 6 | 156 | 297 | 476 |
2005 | 0.76 | 13 | 6 | 236 | 256 | 512 |
2006 | 0.36 | 15 | 9 | 222 | 210 | 457 |
2007 | 0.00 | 15 | 13 | 107 | 161 | 296 |
2008 | 0.00 | 13 | 8 | 60 | 144 | 224 |
2009 | 0.00 | 11 | 8 | 154 | 167 | 340 |
2010 | 0.03 | 17 | 10 | 96 | 156 | 278 |
2011 | 0.00 | 11 | 2 | 72 | 90 | 175 |
2012 | 0.00 | 10 | 0 | 16 | 97 | 124 |
2013 | 0.00 | 13 | 8 | 125 | 135 | 281 |
2014 | 0.04 | 11 | 3 | 163 | 194 | 370 |
2015 | 0.00 | 15 | 16 | 83 | 121 | 235 |
2016 | 0.00 | 14 | 3 | 17 | 184 | 218 |
2017 | 0.00 | 16 | 12 | 50 | 182 | 260 |
2018 | 0.01 | 17 | 8 | 187 | 226 | 438 |
2019 | 0.00 | 9 | 1 | 63 | 187 | 260 |
2020 | 0.00 | 9 | 1 | 154 | 178 | 342 |
1968 to 2020 decadal trend | -19.2% | No trend | -10.3% | -13.5% | -5.8% | -9.9% |
Download data file (Excel/CSV; 2.44 kB)
How this indicator was calculated
Note: The trends presented correspond to the decadal trend over the period from 1968 to 2020. The September multi-year sea ice area trend is calculated based on average multi-year sea ice area during the month of September for each year from 1968 to 2020. A statistically significant trend is reported when the Mann-Kendall test indicates the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
Sea ice in Canada's Northwest Passage
Sea ice area in Canada's Northwest Passage
Canada's Northwest Passage is a system of gulfs, straits, sounds and channels in the Canadian Arctic Archipelago that connects the Beaufort Sea in the west with Baffin Bay in the east. There are 2 main navigation paths through the Northwest Passage: a northern route and a southern route.
Key results
- Over the 1968 to 2020 period, statistically significant decreasing trends were detected for both the total sea ice and multi-year sea ice areas
- Decreases of 3.2% and 7.3% per decade were detected for the sea ice areas of the northern and southern routes of the Northwest Passage, respectively.
- For multi-year sea ice, a decreasing trend of 6.6% per decade was detected for the northern route, while a decreasing trend of 10.7% per decade was detected for the southern route.
- The lowest sea ice area was observed in 2011 for the northern route and in 2016 for the southern route
- The lowest multi-year sea ice area occurred in 1999 for the northern route and in 2012 for the southern route
Average total and multi-year sea ice area, Canada’s Northwest Passage, 1968 to 2020

Data table for the long description
Year | Northwest Passage northern route total sea ice area (thousands of square kilometres) |
Northwest Passage southern route total sea ice area (thousands of square kilometres) |
Northwest Passage northern route multi-year sea ice area (thousands of square kilometres) |
Northwest Passage southern route multi-year sea ice area (thousands of square kilometres) |
---|---|---|---|---|
1968 | 131 | 79 | 84 | 24 |
1969 | 133 | 87 | 68 | 7 |
1970 | 138 | 100 | 68 | 9 |
1971 | 120 | 78 | 56 | 10 |
1972 | 148 | 147 | 71 | 12 |
1973 | 130 | 77 | 90 | 21 |
1974 | 128 | 120 | 39 | 6 |
1975 | 136 | 83 | 66 | 12 |
1976 | 137 | 123 | 73 | 14 |
1977 | 124 | 80 | 77 | 22 |
1978 | 160 | 142 | 65 | 31 |
1979 | 157 | 153 | 94 | 43 |
1980 | 137 | 114 | 77 | 36 |
1981 | 116 | 66 | 54 | 10 |
1982 | 130 | 110 | 40 | 9 |
1983 | 128 | 109 | 50 | 17 |
1984 | 136 | 85 | 48 | 7 |
1985 | 123 | 101 | 55 | 13 |
1986 | 141 | 137 | 67 | 26 |
1987 | 144 | 118 | 96 | 30 |
1988 | 125 | 62 | 84 | 14 |
1989 | 125 | 102 | 69 | 16 |
1990 | 140 | 113 | 76 | 26 |
1991 | 134 | 112 | 80 | 33 |
1992 | 145 | 119 | 84 | 21 |
1993 | 128 | 88 | 84 | 22 |
1994 | 129 | 88 | 87 | 19 |
1995 | 132 | 85 | 69 | 13 |
1996 | 133 | 89 | 69 | 23 |
1997 | 146 | 103 | 93 | 22 |
1998 | 94 | 55 | 60 | 19 |
1999 | 107 | 70 | 12 | 4 |
2000 | 119 | 93 | 26 | 3 |
2001 | 137 | 83 | 64 | 7 |
2002 | 140 | 111 | 53 | 10 |
2003 | 136 | 98 | 77 | 14 |
2004 | 140 | 122 | 91 | 19 |
2005 | 136 | 107 | 86 | 23 |
2006 | 115 | 53 | 66 | 7 |
2007 | 98 | 57 | 44 | 4 |
2008 | 104 | 63 | 32 | 1 |
2009 | 119 | 87 | 29 | 5 |
2010 | 81 | 55 | 20 | 6 |
2011 | 69 | 50 | 15 | 1 |
2012 | 74 | 56 | 20 | 1 |
2013 | 122 | 79 | 22 | 2 |
2014 | 126 | 83 | 31 | 8 |
2015 | 91 | 59 | 24 | 7 |
2016 | 106 | 50 | 48 | 5 |
2017 | 119 | 59 | 59 | 12 |
2018 | 137 | 100 | 58 | 19 |
2019 | 121 | 58 | 76 | 10 |
2020 | 115 | 72 | 61 | 10 |
1968 to 2020 decadal trend | -3.2% | -7.3% | -6.6% | -10.7% |
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How this indicator was calculated
Note: Sea ice area is measured during the summer season. For the Canadian Arctic domain, the summer season is defined as the period from June 25 to October 15. A statistically significant trend is reported when the Mann-Kendall test indicates the presence of a trend at the 95% confidence level.
Source: Environment and Climate Change Canada (2020) Climate Research Division.
Canada's Northwest Passage
Canada's Northwest Passage presents a potential deep-water Arctic shipping route between the northern Pacific and Atlantic regions that is much shorter than routes through the Panama or Suez canals. The Northwest Passage is covered by sea ice for most of the year, making it a navigation obstacle for ice-breaking ships and a safety hazard for non-ice-strengthened ships.
Canada's Northwest Passage

Source: Environment and Climate Change Canada (2018) Climate Research Division
Reduced sea ice is increasing opportunities for shipping, tourism, resource exploration and industrial activities in the North. However, these activities bring new risks of marine accidents from a changing sea ice cover that can put people and ecosystems at risk and place additional stress on limited search and rescue and disaster response capacity.
About the indicators
About the indicators
What the indicators measure
The Sea ice in Canada indicators provide information on the area of sea in Canada covered by ice during the summer season. Sea ice area represents the portion of marine area covered by ice. The area is evaluated using the Canadian Ice Service Digital Archive and is expressed in thousands or millions of square kilometres. The Sea ice in Canada indicators are provided for the Northern Canadian Waters, by sub-region and for the Northwest Passage. The indicators also present trends in total sea ice area and multi-year sea ice area. Multi-year sea ice is defined as sea ice that has survived at least one summer's melt.
Why these indicators are important
Sea ice is an indicator of how the climate is changing. It is a critical component of our planet because it influences the Arctic and global climate, ecosystems, and people who live in the polar regions. Sea ice influences the climate through the sea ice–albedo feedback effect (or reflectivity of the Earth's surface). Changes in sea ice can also affect ocean currents and the exchange of heat and water vapour from the ocean to the atmosphere.
Sea ice affects marine transportation, commercial fishing, offshore resource development, the hunting and fishing patterns of Indigenous peoples, and tourism and recreation. Understanding how Canada's climate is changing is important for developing adaptive responses. The Sea ice in Canada indicators provide a way to communicate to Canadians how the coverage of Canada's Arctic sea ice has changed.
The Intergovernmental Panel on Climate Change and the World Meteorological Organization use sea ice, among several other variables, to assess long-term changes in climate. Sea ice is considered by the World Meteorological Organization's Global Climate Observing System to be an Essential Climate Variable.

Effective action on climate change
These indicators support the measurement of progress towards the following 2019 to 2022 Federal Sustainable Development Strategy long-term goal: A low-carbon economy contributes to limiting global average temperature rise to well below 2 degrees Celsius and supports efforts to limit the increase to 1.5 degrees Celsius.
In addition, the indicators contribute to the Sustainable Development Goals of the 2030 Agenda for Sustainable Development. They are linked to Goal 13, Take urgent action to combat climate change and its impacts.
Related indicators
The Temperature change in Canada indicator measures yearly and seasonal surface air temperature departures in Canada, while the Precipitation change in Canada indicator measures annual and seasonal precipitation departures.
The Snow cover indicators provide information on spring snow cover extent and annual snow cover duration in Canada.
Data sources and methods
Data sources and methods
Data sources
Sea ice data used in these indicators were provided by Environment and Climate Change Canada's Climate Research Division. The sea ice area data were computed from the weekly sea ice charts (Canadian Ice Service Digital Archive) produced by Environment and Climate Change Canada's Canadian Ice Service.
More information
Spatial coverage
The indicators provide coverage for the Northern Canadian Waters which are comprised of the Canadian Arctic domain and the Hudson Bay domain. Five (5) sub-regions make up the Canadian Arctic domain (Kane Basin, Foxe Basin, Baffin Bay, the Beaufort Sea and the Canadian Arctic Archipelago) and 4 sub-regions comprise the Hudson Bay domain (Hudson Bay, Hudson Strait, Davis Strait and the Northern Labrador Sea).
Sea ice sub-regions of the Northern Canadian Waters

Source: Environment and Climate Change Canada (2018) Canadian Ice Service.
Temporal coverage
The indicators are calculated using data for the summer sea ice season for the years 1968 to 2020. The summer sea ice season is defined as the period from June 25 to October 15 for the Canadian Arctic domain and from June 19 to November 19 for the Hudson Bay domain. These intervals correspond to the summer shipping season of each domain, a period during which the Canadian Ice Service produces weekly regional sea ice charts.
Data completeness
The data for these indicators are compiled by the Canadian Ice Service and grouped into time series by the Climate Research Division to ensure comparability. The data incorporate information from many different sources such as satellite data, surface observations, airborne and ship reports, and model results, along with the expertise of experienced ice forecasters. The Canadian Ice Service provides the authoritative Canadian record for sea ice in Canada.
Data timeliness
The data used in the Sea ice in Canada indicators are current up to 2020.
Methods
The Sea ice in Canada indicators are based on the sea ice area data provided by Environment and Climate Change Canada's Climate Research Division.
For each region and sub-region, an average sea ice area is calculated from the summer season weekly sea ice charts for each year, from 1968 to 2020.
A statistical analysis is carried out using the Mann-Kendall and Sen's methods (Kendall-tau) to identify the presence of statistical linear trends at the 95% confidence level.
More information
The Sea ice in Canada indicators use the weekly sea ice charts produced by the Canadian Ice Service. Weekly sea ice charts are primarily produced using imagery from RADARSAT-1 (since 1996) and RADARSAT-2 (since 2008) satellites. Other remote sensing data sources are also used, such as the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer and Moderate-Resolution Imagine Spectrometer imagery. Where possible, the interpretation of satellite data is verified using observations from the Canadian Ice Service specialists onboard dedicated aircraft and Canadian Coast Guard ships.Footnote 7
The Canadian Ice Service ice charts indicate the ice concentration in tenthsFootnote 8 and its stage of development. They also list the mean and normal 1981 to 2010 temperatures of some of the region's stations, which give an indication of one of the factors contributing to current ice conditions. Ice information is presented using the World Meteorological Organization's terminology. For more information about how the Canadian Ice Service produces weekly sea ice charts and maps, consult the Regional Ice Charts or the Manual of Standard Procedures for Observing and Reporting Ice Conditions.
The weekly sea ice charts are compiled into time series by the Climate Research Division for each region and sub-region. The sea ice area for a given year corresponds to the average area calculated from the weekly sea ice charts of the summer season.
The summer season was chosen because it represents the time when the sea ice reaches its minimum area, which is widely utilized within the scientific community as a measure of climate variability. It is also the time period when the most visible changes in sea ice occur. Historically, sea ice charts have been generated to support the shipping season, which is most active during the summer.
Non-parametric statistical tests were carried out on temporal sea ice area data to detect the presence of a linear trend and, if present, to determine the orientation (positive or negative) and magnitude of the rate of change (slope). The standard Mann-Kendall trend test was used to detect trend presence and orientation, while the Sen's pairwise slope method was used to estimate the slope. A trend was reported when the Mann-Kendall test indicated the presence of a trend at the 95% confidence level.
Caveats and limitations
Care should be taken when using these indicators as proxies of the actual sea ice area change in specific locations. Sea ice area change could vary considerably within a sub-region, the smallest unit of analysis in these indicators.
Resources
Resources
References
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Warren FJ and Lemmen DS (Eds.) (2014) Canada in a Changing Climate: Sector Perspectives on Impacts and Adaptation (PDF; 5.5 MB). Government of Canada. Retrieved on November 20, 2020.
Related information
Haas C and Howell S (2015) Ice thickness in the Northwest Passage. Geophysical Research Letters 42(18):7673 to 7680.
Howell SEL and Brady M (2019) The dynamic response of sea ice to warming in the Canadian Arctic Archipelago. Geophysical Research Letters, 46. 13119-13125.
Intergovernmental Panel on Climate Change (2013) Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Chapter 4 Observations: Cryosphere (PDF; 12.5 MB).
National Snow & Ice Data Center (2018) All About Sea Ice.
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