The Arctic tundra ( means tree less), Summertime is the only time for exchange, because ocean and land are too dark in the winter season, and Migratory birds fly to the south. Although Arctic desert is a vast wetland, trees are very short all over ( tall trees attract light), the ground are mostly covered with moss and lichen, and little bit of rain during summer season. Few animals, bird that are mostly carnivores stay throughout the winter.

Arctic has been a challenge for many years, it has shrunk enormously. The Tropic of Cancer North Hemisphere is more dense ( large crowded cities higher carbon emission). In contrast Southern Hemisphere Tropic of Capricorn is less dense (cleaner ocean water).
This region is the most vulnerable in the Northern Hemisphere, because pollinators have limited time ( short summer ) to grow. Summer is the only time for upwelling and marine abundant.

Rajwantee