Interannual variability of Hudson Bay ice thickness

Seasonal sea ice in Hudson Bay plays a key role in determining the regional climatology. In this paper, the relationship between ice thickness with local surface air temperature and snow depth is explored at nine locations in the Hudson Bay region. A weak but statistically significant correlation was found between basin averaged ice thickness and concurrent surface air temperature. At the local scale, however, ice thickness correlated well with winter air temperature at only three measuring sites, explaining the poor relationship at the basin scale. A relationship was also identified between winter ice thickness and previous summer's air temperatures at two measuring sites, suggesting that preconditioning of Hudson Bay waters may play a significant role in sea-ice formation in some subregions of Hudson Bay. Simple and multiple linear regression analyses indicate that at the majority of the measuring sites, snow depth is a more important contributor to the inter-annual variability of ice thickness than winter air temperatures. The results of this study have important implications regarding the use of landfast ice thickness data to detect an early climate change signal over Hudson Bay.