Final answer:
The land surface in the Hudson Bay region is rising due to slow viscous rebound, as the Earth's crust recovers from being depressed by heavy ice sheets during the last ice age.
Step-by-step explanation:
The land surface is rising in the Hudson Bay region of Canada due to slow viscous rebound in response to ice melting over 10,000 years ago. After the last ice age, the weight of the massive ice sheets depressed the Earth's crust, and since the ice melted, the land has been slowly rising back to its original level in a process known as isostatic adjustment or post-glacial rebound.
This is a natural response of the solid Earth to the removal of the heavy burden of the ice sheets. While hotspots can cause the surface to rise due to volcanic activity, in the case of Hudson Bay, the rising ground is not directly related to tectonic activity or heat flow from the mantle but is rather a lingering effect of the last glacial period.