As we watch the ongoing rapid loss of Arctic sea ice, freshwater ice, permafrost, and spring snow cover, the corresponding amplified warming of the Arctic region (AAW) continues to increase. These disturbing changes to a key component of the Earth’s climate system has spawned a blizzard of new studies that reveal influences of AAW on weather patterns within and beyond the Arctic.
Warming air temperatures and associated major reductions in the Arctic sea ice cover are driving increases in ocean temperature and changes to circulation patterns in the region. These changes are expected to impact the biogeographic boundaries of a range of marine species. For example, it is anticipated that many organisms may migrate northward or become more abundant as air and ocean temperatures continue to warm. However, few pose such significant threats to human and ecosystem health as harmful algal bloom (HAB) species.
The Arctic Ocean contains only about 1% of global ocean volume but receives greater than 10% of global river discharge. Consequently, terrestrial influences via river inputs are much stronger in the Arctic Ocean than in other ocean basins. Rapid change in the Arctic system is altering land-ocean linkages, impacting coastal and ocean physics, chemistry, and biology.
Lake ice is an important component of the cryosphere for several weeks to several months of the year in high-latitude regions. The presence (or absence) of ice cover on lakes during the winter months affects both regional weather and climate (e.g., thermal moderation and lake-induced snowfall). Hence, monitoring of lake ice is critical to our skill at regional forecasting.
The abundance of migratory herds of caribou (North America and Greenland) and wild reindeer (Russia and Norway) in circum-arctic tundra regions has declined 56% over the last two decades. Caribou and wild reindeer are a key species in the arctic food web contributing to nutrient cycling between terrestrial and aquatic systems and the abundance of predators and scavengers.
The Arctic Report Card (hereafter ‘ARC’) has been issued annually since 2006. It is a timely and peer-reviewed source for clear, reliable and concise environmental information on the current state of different components of the Arctic environmental system relative to historical records. The ARC is intended for a wide audience, including scientists, teachers, students, decision-makers, and the general public interested in the Arctic environment and science.