Final answer:
Maritime polar air originates from cool, high-latitude ocean areas and forms around the polar regions, influenced by the cold conditions near the Arctic Circle and the Subtropical Convergence around the Southern Ocean.
Step-by-step explanation:
Maritime polar air masses originate from cool, high-latitude areas of the ocean. They form mainly around the polar regions and in the vicinity of the Subtropical Convergence, where the cold southern waters meet the warmer northern waters. The origin of maritime polar air in the Northern Hemisphere is typically over the northern Atlantic and Pacific Oceans, influenced by the colder environments of areas such as near the Arctic Circle in Norway and Iceland. In the Southern Hemisphere, it is influenced by the cold, dense water sinking below warmer northern waters, creating zones of upwelling around the Southern Ocean's boundary, further supporting high levels of productivity in marine organisms such as krill and phytoplankton.