Why is the Port of Churchill open for only a short period each year?

The Port of Churchill, located on the west coast of Hudson Bay, experiences a limited shipping season primarily due to the region's severe continental climate and the presence of ice.12

The bay is characterized by extremely cold temperatures, with January averages reaching -20 °F (-29 °C). Consequently, the water is subject to significant ice formation, including local ice and pack ice that drifts in from the north. While the spring thaw begins in late April, the harsh winter conditions and the persistence of floating ice fields—which are particularly prevalent in the southern and central areas during February and March—restrict maritime navigation to a short period each year when the waters are sufficiently clear.2