East–west asymmetry in long-term trends of landfast ice thickness in the Hudson Bay region, Canada

Alexandre S. Gagnon, William A. Gough

Research output: Contribution to journalArticle

Abstract

Ice cover in the Hudson Bay region (HBR) goes through a complete cryogenic cycle each year. Freeze-up typically occurs in October and November, ice cover reaches its peak thickness from late March to May, and water bodies in the HBR are usually ice-free beginning in early August. In this study, the timing and magnitude of the annual peak in ice thickness were identified for each year from weekly ice observations compiled by the Canadian Ice Service. The Mann-Kendall test was used to determine the statistical significance of the temporal trends, and their magnitude was estimated using the Theil-Sen approach. The results indicate an asymmetry in temporal trends of landfast ice thickness; statistically significant thickening of the ice cover over time was detected on the western side of Hudson Bay, while a slight thinning lacking statistical significance was observed on the eastern side. This asymmetry is related to the variability of air temperature, snow depth, and the dates of ice freeze-up and break-up. Increasing maximum ice thickness at a number of stations is correlated to earlier freeze-up due to negative temperature trends in autumn. Nevertheless, changes in maximum ice thickness were reciprocal to the variability in the amount of snow covering the ground. These results are in contrast to the projections from general circulation models (GCMs), and to the reduction in sea-ice extent and thickness observed in other regions of the Arctic. This contradiction must be addressed in regional climate change impact assessments.
Original languageEnglish
Pages (from-to)177-186
Number of pages10
JournalClimate Research
Volume32
Issue number3
Publication statusPublished - 26 Oct 2006
Externally publishedYes

Fingerprint

ice thickness
Ice
asymmetry
ice cover
ice
snow
regional climate
thinning
general circulation model
sea ice
air temperature
Snow
autumn
climate change
long-term trend
Sea ice
trend
temperature
Climate change
Cryogenics

Keywords

  • Hudson Bay
  • Lake ice
  • Sea ice thickness
  • Snow depth
  • Temperature trends

Cite this

Gagnon, Alexandre S. ; Gough, William A. / East–west asymmetry in long-term trends of landfast ice thickness in the Hudson Bay region, Canada. In: Climate Research. 2006 ; Vol. 32, No. 3. pp. 177-186.
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East–west asymmetry in long-term trends of landfast ice thickness in the Hudson Bay region, Canada. / Gagnon, Alexandre S.; Gough, William A.

In: Climate Research, Vol. 32, No. 3, 26.10.2006, p. 177-186.

Research output: Contribution to journalArticle

TY - JOUR

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AU - Gough, William A.

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