Final answer:
Minnesota is uplifting by several millimeters per year due to the melting of glaciers and polar ice caps, and thermal expansion. This causes an increase in the global sea level, with fluctuations between 2.9 and 3.4 mm per year. Warming air temperatures and positive feedbacks also accelerate ice melting.
Step-by-step explanation:
Minnesota is currently uplifting by several millimeters per year primarily due to the melting of glaciers and polar ice caps, which contributes about 2.4 mm/yr of rise, and thermal expansion, which accounts for about 1.2 mm/yr. These factors result in a total rate of 3.6 mm/yr of uplift.
The melting of ice causes an increase in the volume of liquid water in the ocean, leading to a rise in the global sea level. This rise in sea level is not uniform, with fluctuations ranging between 2.9 and 3.4 mm per year between 1993 and 2010, due to various factors such as temperature changes and the amount of water in rivers, lakes, glaciers, and sea ice.
As glaciers and polar ice caps melt, the previously frozen water contributes to the overall volume of liquid water in the ocean, causing the sea level to rise. Additionally, the warming air temperatures and positive feedbacks, such as the absorption of solar energy by dark melted pools of water on top of the ice, accelerate the rate of ice melting and thus the uplift of Minnesota.