Oil Spill Risks in the Chukchi Sea Planning Area
While regulatory improvements have decreased the probability of a large oil spill, these activities still pose risks in this remote and harsh Arctic environment. These risks are particularly significant in a complex and fragile ecosystem such as the Chukchi Sea.
The Bureau of Ocean Energy Management (BOEM) has released a draft supplemental environmental impact statement to reaffirm the 2008 Lease Sale 193. The Emmett Environmental Law & Policy Clinic submitted comments on this DSSEIS.
The sea ice in the northern Bering and Chukchi Seas plays a critical role for marine mammals, fish, birds and other Arctic wildlife. It also provides valuable habitat for the benthos and supports Alaska Native subsistence harvests. The health of the chukchi seas is essential to the region’s residents and visitors.
We use satellite and model data to examine ice and sea state trends across the planning area. Our analysis includes both observational and modeling data from the period of 1979-2016, with an emphasis on early winter (November-December) sea ice advance (SIA). We define our analytical domain as an area-preserving rectangle that expands northward in latitude to include the waters of Hope Basin.
We investigate predictability of SIA in early winter using canonical correlation analysis. The leading CCA modes relate to ocean surface heat content and lateral advection anomalies in the upstream Pacific Ocean. This suggests that the interannual variability in SIA in early winter is controlled by an initial condition of the summertime SIC.
The coastal region of the Chukchi Sea is covered with sea ice from winter through early summer. The ice provides habitat for marine mammals that include ESA-listed gray whales and belugas, and Pacific walrus.
During the fall migration, bowhead whales disperse through the Chukchi Sea and move between coastal areas and the ice front. The planned seismic survey activity is not expected to interfere with whale migrations in the area.
In the nearshore area, ESA-listed long-tailed ducks may be encountered. Long-tailed ducks are highly sensitive to sound, and their occurrence in the vicinity of Statoil’s 3D seismic surveys raises concern about their vulnerability to exposure to oil and drilling mud from vessel activities. The FEIS addresses concerns about the impact of seismic survey noise on these birds by providing a range of effect levels determination results for a number of sensitivity factors. The FEIS also includes information for use by NMFS to issue Incidental Harassment Authorizations for seismic-survey companies incidental to conducting prerelease and ancillary on-lease oil and gas exploration activities under the Marine Mammal Protection Act (MMPA). The FEIS is available on BOEMRE’s website.
Birds in the Arctic Sea are highly mobile, and can move across large distances to follow food sources. They are also highly dependent on ocean currents and surface conditions for their movement, migration, and breeding.
The chukchi sea planning area includes important migratory habitat for a variety of species including black-legged kittiwakes, short-tailed shearwaters, loons, and sea ducks. Several of these species are sensitive to seismic survey sounds.
In addition to seabirds, the chukchi sea planning area is important for Pacific walrus, ringed and bearded seals, and bowhead whales. It also contains large portions of designated critical habitat for polar bears, and is an important staging area for polar bears during fall migration.
The federal and state governments share responsibility for managing ground fish in the Chukchi Sea. The federal agency is the National Marine Fisheries Service. The state agency is the Alaska Department of Fish and Game.
This study will document, characterize and understand the distribution of pelagic and demersal fish and invertebrate communities in the lease area. It will also compare these communities with that of adjacent regions (Beaufort and Bering Seas) to understand the influence of oceanographic fronts. It will also provide a base of information for developing a mass-balance food web model of the eastern Chukchi Sea, incorporating collected diet data from bottom trawl surveys.
MMS’s FEIS found that alternative IV (Corridor II Deferral) for the 2008 CSLA 193 and associated seismic surveying and exploratory drilling would not jeopardize the continued existence of Steller’s or spectacled eider, destroy or adversely modify designated critical habitat, or otherwise jeopardize the Coastal Plain Wetlands Conservation Strategy. However, more information on species-specific growth variation is needed.