The Chukchi Sea Map
The Chukchi Sea is a focus of resource exploration and vessel transits in the Arctic Ocean. Consequently, there is high interest in understanding its changing ice cover on decadal and seasonal timescales that bear directly on economic activities.
Figure 1 shows satellite-derived sea ice concentration values, polar bear track index, and predicted polar bear abundance for each of the study grid cells.
The Chukchi Sea is bounded by Wrangel Island and Russia’s Arctic coast in the west; the Beaufort Sea, Point Barrow, and Alaska’s coastal regions in the east; and the Bering Strait and Pacific Ocean in the south. The sea is roughly shaped like a rectangle with flat plateau-like crests that are intersected by north-south trending normal faults.
Dredged rock samples from the Chukchi Borderland include deformed calcareous sandstone and slate. Zircon data from these rocks indicate that they have a Cambrian to Silurian age and were deposited along the ancient North American continental margin of Arctic Canada.
The ice-edge habitats of the Chukchi Sea are vital for several marine Arctic mammals, including polar bears, and serve as breeding, resting, and feeding areas for them and other seabirds. The sea also provides a source of ice-edge-dependent phytoplankton that is essential to marine Arctic ecosystems. This region is a mainstay for subsistence hunting, a key element of northwest Alaska traditional economies.
The Arctic’s Chukchi Borderlands is a dynamic marine landscape where cold and fresh Arctic waters mix with the warm and salty Pacific. Here, ice-dependent species including polar bears and whales find habitat. This region also hosts a growing energy industry and complex topography.
A northward flow through Bering Strait transports important contributions of nutrients, heat and biota from the northern Bering Sea to the Chukchi Sea. This interaction is critical to the ecosystem.
Our carbon isotope study of a sediment core from Herald Canyon in the Chukchi Sea shows that a progressive increase in the amount of Pacific Water (PW) flowing through the Bering Strait has occurred since 11,000 cal years BP, linked to climate warming and sea level rise. Lignin biomarkers suggest that PW-derived PF-C from gymnosperm vegetation has been the dominant source of EC to the Chukchi Sea throughout the Holocene.
Recent shifts towards a longer open-water season and reduced sea ice cover in the Arctic may cause surface waters in the Chukchi Sea to become more corrosive. This has the potential to significantly affect the ocean’s uptake of carbon dioxide, influencing global climate change.
Unlike most Arctic seas, the Chukchi has very few islands. The principal ones are Wrangel Island and Herald Island, located off the northwestern edge of the sea, and a few smaller islands along Alaska’s and Siberia’s coastlines.
Thick multiyear ice and deep-draft pressure ridges in this sea can pose significant navigation hazards to vessels. These features can also damage offshore drilling platforms and buried pipelines.
This sea is an important thoroughfare for migratory whales, walruses and other marine wildlife that travel between the Bering Strait and the Beaufort and Chukchi Seas. Protecting areas of vital habitat is essential to ensure these animals and marine mammals can continue to use this critical migration corridor in the future. The Chukchi Sea’s Arctic slope is also a key food source for caribou, bearded and ringed seals, which provide a vital source of meat and fish protein for human populations in Alaska and beyond. Radiocarbon dating shows that these seals have been harvested from the region for millennia.
The Chukchi Sea is important habitat for a number of species including polar bears, walruses, and marine mammals. Its ice-edges provide feeding, breeding, and resting areas for a variety of seals. Birds, including raptors, shorebirds, and waterfowls, also use this sea as a nesting area.
In spring, a lack of sea ice impacts the entire Arctic ecosystem and changes underwater light irradiance, stratification/mixing, and nutrient replenishment. This information is critical for forecasting and management of the Arctic ocean.
Audubon Alaska and Oceana have completed a place-based summary of the Arctic Marine Synthesis for the Chukchi and Beaufort seas. This atlas is a valuable tool for setting conservation priorities and designing balanced management plans for the region. It provides a more holistic look at this dynamic Arctic ocean ecosystem. The full atlas is available here.