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CHAPTER 2 Environmental Conditions and Natural Resources in the U.S. Arctic The components of the Arctic system interact with each other in a complex, evolving pattern. This chapter provides an overview of the physical and biological ocean processes and environments of the Bering Strait and the Chukchi and Beaufort Seas. This is important for understanding current conditions, but also for trends, changes, and future data needs. This knowledge is essential to support safe operations in the Arctic marine environment; to guide oil spill prevention, response, and restoration; and to prioritize sampling and monitoring needs. The chapter begins with a discussion of the physical environment: ocean, marine weather, sea ice, and coastal characteristics and processes—conditions that would be encountered in the event of an oil spill in Arctic waters. A discussion of Arctic ecosystems follows, with an emphasis on biological information that would be important for oil spill response, including monitoring approaches and data needs for incorporation into spill trajectory models or ecosystem models. A final section discusses current research and monitoring as well as additional needs to advance understanding of the Arctic system. OCEAN PROCESSES AND CHARACTERISTICS Three principal branches of Pacific origin water (Alaska Coastal Water, Bering Shelf Water, and Anadyr Water; Figure 2.1) enter the Bering Strait and circulate through the Chukchi and Beaufort Seas. The northward transport of water through the Bering Strait is principally driven by large-scale sea-level differences between the Pacific and Arctic Oceans, and opposes the prevailing winds; variability in the currents is predominantly wind-driven (Weingartner et al., 2005). The summer retreat of ice in this sector of the Arctic has been linked in part to warm Bering Strait inflows and flow pathways (Woodgate et al., 2010). Water properties in the Chukchi Sea are set by processes of sea ice melt and growth, winds, and inflows of river water and Pacific Ocean via the Bering Strait, as well as from the East Siberian Sea. Transport of water from the Chukchi and shelf regions to the deep Canada Basin takes place mainly through the Barrow and Herald canyons (Weingartner et al., 2005). Currents that flow eastward along the Beaufort Sea continental slope generate eddies that can propagate into the basin interior, and surface wind forcing can also drive water offshore (e.g., Pickart et al., 2005). Transport pathways, seasonal evolution, and mixing of the water masses are outlined in Weingartner et al. (2013a) and references therein. Weingartner et al. (2005) found that mean flows over the Chukchi shelf are generally less than 10 km/day except in Barrow Canyon, where maximum current speeds can briefly reach 85 km/day. Elsewhere in the Chukchi Sea, maximum currents are between approximately 25 and 40 km/day. The mean flow is north-northeastward over the central Chukchi shelf, opposite to the mean winds. Weingartner et al. (2013b) examined in detail winds and water properties over the central portion of the northeastern Chukchi Sea shelf (40-45 m depth) in summer and fall 2008- 2010. They showed that temperature and salinity properties can vary significantly over only a few tens to a hundred kilometers. Along the shoreline of the Beaufort Sea in open water or loose ice conditions (July to mid-October), surface currents are predominantly wind driven (speeds typically exceed 8 km/day and maximum currents can reach almost 80 km/day, while in winter under fast ice, currents are weak—less than ~2.5 km/day—and forced predominantly by tides) 23 PREPUBLICATION COPY

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24 Re esponding to Oil Spills in the U.S. A n Arctic Marine Environme e ent (Okkonen and Weing n gartner, 2003 Of utmos importanc e to oil spill response is the rapid 3). st l variabilit of the win ty nd-forced sur rface ocean circulation. H c High-freque ency radar sy ystems in the e Chukchi Sea, which map surface ocean curre m e ents, indicate complex fl patterns that can rev e low verse direction in a matter of hours and can vary si n d ignificantly i both magn in nitude (0-85 km/day) an 5 nd direction over spatial scales of le than 10 km. n l ess k Figure 2.1 Water masses and sea ice ex 1 s xtent in Bering Strait and Chu g ukchi and Beau ufort Seas. Sou urce: Grebmeie er, 2012. The Arctic Ocean is stron T ngly stratified, with a fre low-den esh, nsity mixed layer up to 40 m deep in th Beaufort Sea. In the summer, ver fresh, war mixed lay only a f meters d he s ry rm yers few deep are obser rved in parts of the Chuk and Bea kchi aufort Seas ( e.g., Toole e al., 2010; Weingartner et et r al., 2013a This strat a). tification has important implications for the path i s hways and fa of spilled oil. ate d In the De eepwater Ho orizon spill, oil plumes ri o ising through the stratifi ocean wa column h ied ater spread ou at some le of neutral buoyancy and became trapped at depth (Soco ut evel y e olofsky et al., 2011). Th impact of the strong Arctic Ocean stratificatio on the su he f A n on ubsurface evo olution of sppilled oil, partic cularly when surfactants are used (e. Adalstein n s .g., nsson et al., 2011), is an important n response planning co onsideration, as oil that is trapped at depth will n be transported by sur , not rface circulatio For this reason, there is a need fo characteriz on. r e or zation and mmonitoring o Beaufort a of and Chukchi subsurface circulation, which can be as complex as the surf c w e x face flow and can be in d opposing directions (e.g., Weingartner et al., 1998; Prosh g ( hutinsky et a 2009; Mo al., orison et al., 2012). Contaminants residing eit C s ther in the su urface or in t subsurfa ocean are subject to the ace e redistribuution by coastal ocean up pwelling and downwelli events; s d ing such events hhave been w well studied in the Beaufo Sea (see Williams et al., 2006; Sc n ort W chulze and P Pickart, 2012 Pickart et al., 2; 2013). St trong easterl winds hav been observed to bring warm, salt deep wate to shallow ly ve g ty er w PREPUB BLICATION C OPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 25 depths along the Beaufort Sea continental slope, with increased frequency of upwelling events in the absence of concentrated pack ice (Pickart et al., 2009). Similarly, downwelling events forced by westerly winds cause the descent of near-surface waters along the coast (Dunton et al., 2006). Ocean eddies are common in both the Chukchi Sea and the Beaufort Sea (e.g., Manley and Hunkins, 1985; Pickart et al., 2005; Timmermans et al., 2008). Eddies centered at depths ranging from a few tens to hundreds of meters (with horizontal scales from a few kilometers to tens of kilometers) can trap and transport packets of water, or (in the case of a spill) entrained oil, over hundreds of kilometers (Provenzale, 1999; Haller and Beron-Vera, 2013). Satellite measurements reveal that the surface distribution of oil in the Deepwater Horizon spill was influenced by eddies in the Gulf of Mexico, which can extend to 800 m depth (Walker et al., 2011). In addition to larger-scale eddies, there is complicated smaller-scale flow structure (characterized by horizontal scales around 1 km or less) in the ocean mixed layer beneath sea ice in the Beaufort Sea (Timmermans et al., 2012) and in the mixed layer in ice-free conditions in the Chukchi Sea (Timmermans and Winsor, 2013). This small-scale flow field, which is characterized by strong convergence and divergence zones, has been shown to have an important influence on tracer distribution patterns in midlatitude, ice-free regions (Zhong and Bracco, 2013). Ocean storm surges related to persistent high winds are an important factor for consideration in coastal spill response. Loss of Arctic sea ice has been shown to increase storm surge frequency (Lesack and Marsh, 2007; Pisaric et al., 2011). Extreme coastal flooding from water forced onshore by winds has been documented along the Canadian Beaufort Sea coast (e.g., Harper et al., 1988, who show maximum storm surge elevations of 2.5 m above mean sea level recorded at Tuktoyuktuk, Northwest Territories, Canada). These storm surges move ocean water into low-lying coastal environments, bringing salt and contaminants (in the event of a spill) that can have negative impacts on nearshore and terrestrial ecosystems (e.g., Thienpont et al., 2012). MARINE WEATHER AND SEA ICE PROCESSES Marine Weather There are a number of key weather parameters in the Beaufort and Chukchi region that can affect oil spill response, including air and water temperature, winds, low visibility, and hours of daylight. These conditions were highlighted as challenges to oil and gas operations and scientific research in the Arctic by the National Commission on the BP Deepwater Horizon Oil Spill (2011), among others. Figure 2.2 shows a temperature record collected at Barrow over a five year period from 1999 to 2005 (Syzmoniak and Devine, 2006). Air temperatures are low through most of the year and exhibit little variability from year to year (Figure 2.2). PREPUBLICATION COPY

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26 Re esponding to Oil Spills in the U.S. A n Arctic Marine Environme e ent Figure 2.2 Monthly aver 2 rage temperatur at the Barro Automated Surface Obser res ow d rving System ( (ASOS) from 1 1999- 2005. Sour Syzmoniak and Devine, 2006. rce: k 2 Stegall and Zhang (2012) analyzed th ) hree-hourly N North Ameri ican Region Reanalysi nal is winds in an in-depth review of wind statistics in the Chu w ukchi–Beaufo Seas and Alaska Nor ort d rth Slope reggion for the period 1979- p -2009. They found a dis tinct seasona cycle, wit lowest win y al th nd speeds (~~2-4 m/s) in May and lar rgest (~9 m/s) in Octobe with extre winds (u to 15 m/s er, eme up s) that are most often fo m ound in Octo ober. An incr reasing trend in the frequ d uency and inntensity of extreme wind events was identifi over thei study perio 95th per w ied ir od; rcentile wind in October ds r increased from 7 m/s in 1979 to 10.5 m/s in 2009. Wind fields over o d s 2 offshore area are not alw as ways well-capt tured by coaastal station data, which comprise the majority of source data for reanaly d c e a ysis winds. Fo example, along the North Slope, the significa influence of the Broo Range in or t ant e oks n winter an the sea br nd reeze effect from thermal gradients b f between land ocean, and ice in summ d, d mer can lead to stark diffe ferences betw ween the coa astal and offsshore wind rregimes. Win measurem nd ments from Pell Island in the Canadian Beaufort Sea, which m better re ly t n S may epresent the sstronger and d more var riable Beaufo Sea marin winds tha coastal sta ort ne an ations to the west (see M e Manson and Solomon 2007), reco n, orded peak wind speeds of more tha 20 m/s in m months in the perio w an most od 1994-200 (Fissel et al., 2009). Wind speed distribution can be used to assess ho often a sp 08 W d ow pill response technique su as in situ burning co uch u ould be used For examp a general upper wind d. ple, l d limit for successful ig gnition and effective bur e rning in boo ms or in situ burning is on the order of u r 10 m/s (BBuist et al., 1994). 1 Limited dayli L ight can be a major issue for oil spill response du e l uring freeze- and over the -up r winter. Off the Beauf coast, th maximum of 21 hours of daylight during the b O fort he m s t breakup seasson in Augus reduces to an average of 11 hours in October. However, in practice, tw st n wilight can increase the available operationa time beyon the hours of sunrise to sunset. Fro late e al nd o om Novembe to January there is no daylight. Lo er y ow-visibility conditions in the Beauf Sea offs y fort shore occur mo often dur ost ring the break period in July and A kup August. In coontrast, the f freeze-up perriod in Octobe has less li er ikelihood of low visibilit (DF Dick Associat Ltd. et al 2000). ty kins tes l., The Beaufort Sea wave en T nvironment can present a significant challenge t oil spill t to response. Waves are predominan generate during the open water season and generally ntly ed e r propagate from the east and north heast, althou recent an ugh nalyses sugg sizeable waves now also gest come fro the west (Fissel et al., 2012). For much of the summer (Ju to Augus the close om ( e uly st), e proximity of sea ice is thought to prevent hig sea states from formin However since 2001 y i o gh ng. r, 1, PREPUB BLICATION C OPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 27 upward-looking sonar measurements in the Beaufort Sea have shown a trend of large waves being present in summer and fall for longer durations, with significant interannual variability in wave heights (Fissel et al., 2012). It has been hypothesized that because of larger fetches in summer, the summer wave field now contributes significantly to a marginal ice zone of broken- up floes along the Beaufort Sea ice edge. After the initial freeze-up in October, wave heights become limited. During open water periods, maximum sea states can be estimated using the Beaufort scale relationship. The Meteorological Service of Canada has provided a wind and wave hindcast of the Beaufort Sea, covering a 41-year period between January 1970 and December 201012 (see also an earlier study by Eid and Cardone, 1992). The maximum significant wave height over this period in the southern Beaufort Sea was ~9 m, with mean significant wave heights ~1-2 m. Francis et al. (2011) examined significant wave heights in the Chukchi Sea during 1993-2011 and found a 2-2.5 cm/yr increase in significant wave height, which is consistent with increased fetch accompanying sea ice retreat in this region over the same period. It is of note that about 80 km offshore there is good correlation between wave heights determined from moored measurements and satellite observations in the southeast Chukchi Sea, with worse agreement closer than ~10 km to the coastline. Depending on the time of year, different sets of operating limits can cause interruptions to marine and air activities. From December to March, sea state is not an important factor. Operational downtime is dominated by darkness, snow, and low temperatures. Sea state and temperature are not critical factors from March to June or July; instead, downtime is related to wind and visibility such as fog and low clouds. From August to October, sea state is an important factor, while low air temperature and increasing darkness become critical from late October onward. Box 2.1 illustrates some examples of risk factors in the marine operating environment and demonstrates ways weather parameters can have an impact on marine operations and response. BOX 2.1 Examples of Risks Associated with Oil Spill Response Due to Weather Conditions Adverse weather conditions can have impacts on the feasibility of oil spill response, especially in relation to marine and airborne operations in support of the response. This box provides examples of risks associated with particular weather conditions. Actual operating limits are determined by an operator for each installation and piece of equipment.  Sustained wind speeds greater than 25 knots (~13 m/s) could o Hinder crane operations and equipment use on response vessels, with a possibility of swinging or uncontrollable loads; o Limit in situ burning, as a typical wind threshold for successful burn operations is 20 kt (~10 m/s) or less; o Hamper small boat operations due to the potential for severe sea states, breaking waves, and superstructure icing; and o Hinder helicopter approach and landing on offshore helidecks.  Sea states greater than 1-1.5 m could o Limit boom effectiveness, as wave overtopping leads to loss of contained oil; o Impede small boat operation, due to waves, wind, and icing potential; o Contribute to seasickness and/or fatigue, impacting personal safety and effectiveness; and 12 See http://www.oceanweather.net/msc50waveatlas. PREPUBLICATION COPY

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28 Responding to Oil Spills in the U.S. Arctic Marine Environment o Jeopardize safety on deck from slippery and icy surfaces.  Visibility that is less than visual flight rules or instrument flight rule minimums could o Limit helicopter landings when cloud ceilings or visibility are below minimum standards set by the Federal Aviation Administration or company policy; and o Limit oil spill monitoring by preventing direct visual observations.  Extreme cold temperatures (less than −35°C) could o Impact safety on deck, due to effects from wind chill; o Impact responder safety because of potential for frostbite; o Decrease worker efficiency from fatigue, leading to a need for frequent rest breaks; o Contribute to equipment breakdown due to changes in oil viscosity, hydraulic leaks, or mechanical failure; and o Limit helicopter operations, which have a lowest acceptable operating temperature set by operators and manufacturers. Sea Ice Sea ice is a critically important component of the Arctic marine environment, and understanding the ice environment is essential to anticipating the likely behavior of oil in, under, and on ice and determining applicable response strategies. At present, marine operations in the northern Chukchi and Beaufort Seas generally take place from late July to September, but future developments could lead to extended operating seasons or even year-round offshore oil production. Even in the summer, ice can intrude on drilling locations and shipping routes. Furthermore, ice-free regions can transition to ice-covered conditions in a matter of days at the start of fall freeze-up. Sea ice therefore needs to be considered as a possible operating condition for spill response planning. In areas that are of interest to industry, sea ice monitoring is generally performed more consistently and with higher resolution than elsewhere in the Arctic. This section describes seasonal and spatial characteristics of the Beaufort and Chukchi Sea ice environments in order to set the context for spill response procedures and obstacles in the next chapter. For additional background, the National Snow and Ice Data Center (NSIDC) provides concise descriptions of many key processes in ice formation and decay, as well as the different forms of sea ice13 (recent sea ice conditions are also summarized in Perovich et al., 2013). Worldwide standards for sea ice charting and reporting are maintained by the Joint World Meteorological Organization-Intergovernmental Oceanographic Commission Technical Commission for Oceanography and Marine Meteorology, while the Arctic and Antarctic Research Institute in Russia maintains the current web-based edition of “World Meteorological Organization WMO-IOC Sea Ice Nomenclature No. 259.” Ice concentration, the areal extent of ice relative to open water, is expressed as tenths of ice coverage (e.g., 1/10 = 10% coverage of ice by area). Sea ice has a complicated seasonal evolution that is a function of seasonal temperature variations and mechanical forcing; its structure and evolution differ significantly from the coastal zone to offshore. Land-fast ice refers to sea ice that is frozen along the shore, partially frozen to the seabed in shallow water (less than 2 m), and largely free-floating in deeper water (typically 15-30 m), where grounded ridges can act to anchor the sheet against drifting pack ice forces. Land-fast ice is most extensive along broad, shallow shelves. Although fast ice along the Beaufort Coast is generally stable near shore after December, severe storm events can cause 13 See http://nsidc.org/cryosphere/seaice/index.html, accessed March 2014. PREPUBLICATION COPY

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Environm mental Cond ditions and Natural Resou N urces in the U.S. Arctic 29 winter shhearing and movement an breakawa events, w m nd ay where large seections drift away from the fast ice edge in deepe water. The events ar more com er ese re mmon off par of the Ch rts hukchi coast.. Beyond the bottom-g t grounded lan nd-fast ice zo floating fast ice exte one, g ends seawar as the seas rd son progresse until it re es, eaches an out limit with a shear z ter hin zone (Eicken et al., 2006 Figure 2.3 n 6; 3); this zone of often sig e gnificantly deeformed ice can be highl variable i extent but typically oc ly in ccurs between the 15- and 25-m isobat (also refe ths erred to as th Stamukhi zone in trad he ditional Alaskkan reference such as Ko es ovacs [1976] and Reimn and Kem nitz mpema [1984 The stab and relati 4]). ble ively smooth nearshore are of land-f ice (out to approxim n eas fast t mately 12 m wwater depth) are used in the Beaufort Sea along th North Slo to constr winter ic roads that routinely c he ope ruct ce t carry heavy equipmen in midwin (Potter et al., 1981; Masterson, 2 nt nter e M 2009). Land d-fast ice also serves as a o an importan hunting an traveling platform for Arctic coast communities, as note by Mahon nt nd p tal ed ney (2012). Figure 2.3 Cross-section of typical Bea 3 n aufort Sea ice zones. Source: Used with per z rmission from G Geophysical Institute, University of Alaska Fairbank U A ks. Drift ice float freely on the ocean su D ts t urface withou any stable connection to land. Pac ice ut e ck is drift ic whose con ce ncentrations exceed 6/10 The pack c open or close on the order of hou 0. can e urs in respon to winds and/or ocea currents (A 2012). Typical mid nse an API, dwinter pack ice drift rates in k the Beaufort Sea are on the order of 5 km/day (Melling a Riedel, 2 r y and 2004). Ice dr rates can rift n exceed 50 km/day, based on 80th percentile exceedance values publi h e ished by Meelling et al. (2012) fr rom mooring in the Can gs nadian Beauf Sea. Pea values me fort ak easured in th same data he aset over a 30 0-minute per riod reached 1.2 m/sec. Even higher short duratio speeds (u E on under 12 hou urs) are possible along the U.S. Beauf Sea coast, where the mountain b e fort e barrier effect of the Broo t oks Range am mplifies offshore east-we winds. Th net displa est he acement of i past a mi ice id-shelf site n north of Tuktoy yaktuk betwween mid-October and mid-May was almost 2000 km in 2007-2008. The m 0 e actual dis stance along a drift path, including loops and ba g ack-tracking, could be lar , rger. PREPUB BLICATION C OPY

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30 Responding to Oil Spills in the U.S. Arctic Marine Environment The distinction between fast ice and pack ice and the location of the ice edge at different times in the winter has important implications for oil fate and behavior. Ice features embedded in fast ice are generally static, so oil spilled into this stable ice regime is likely to remain very close to the discharge point (within hundreds of meters) for much of the year. In contrast, oil spilled into a pack ice environment north of the fast ice edge will drift with the ice over time (Wadhams, 1976, 1981; Wilkinson et al., 2007; Dickins, 2011). In addition to location, the timing of a spill in relation to the sea ice seasonal cycle can control oil behavior and related response options. When sea ice first forms on the ocean surface in the fall, it transitions through a range of stages (depending on atmospheric and ocean conditions)—a growth process that eventually leads to first-year ice, which in a single season may become 1.5 to 2 m thick by late winter (April/May) in the Chukchi and Beaufort Seas (DF Dickins Associates Ltd. et al., 2000; Wadhams et al., 2011; Wadhams, 2012a). Oil spilled under growing first-year ice will become encapsulated in a layer of new ice within 12-48 hours, depending on the thickness of the ice, snow cover, and ambient air temperature. This process has been documented in a series of large-scale field studies (Dickins and Buist, 1999; Dickins, 2011). In most Arctic areas, the overlying snow layer usually starts to melt in late May or early June and is gone by early July. Meltwater from the snow creates a network of meltwater pools over the ice surface. In first-year ice, oil trapped under or encapsulated within the ice will migrate to the surface through channels left in the ice as the heavier brine drains out. Once on the ice surface, winds will push the oil into thicker patches on the lee side of melt pools that can be ignited and burned (NORCOR Engineering & Research Ltd., 1975; Dickins and Buist, 1981; Brandvik et al., 2006). Much of the ice cover encountered beyond the nearshore land-fast ice zone is deformed from crushing and shearing or from young ice rafting over itself in the first few months following freeze-up, forming ridges and ice rubble. These processes can create several-meters- thick patches of ice made up of multiple thin sheets. Ridges can extend well over 30 m below the surface and 5 m or more above the surrounding ice field (Tucker et al., 1979; Wadhams and Horne, 1980; Weeks and Hibler, 2010). Monitoring ice thickness is a particularly serious technical question, as current satellite methods are deficient in this area; both CryoSat and ICESat satellite sea ice thickness data are subject to issues regarding validation. Recent progress has been made through the analysis of distributed moored sonar measurements in the Beaufort Gyre region from 2003 to 2012 (Krishfield et al., 2014). Over this period, Krishfield et al. (2014) found an increase in the fraction of ice floes less than 0.3 m thick and a reduction in older thicker ice floes. A 0.5-m decline in mean ice draft over the nine year period was observed; most of this decline in sea ice thickness occurred in 2007 and 2008. Even areas of smooth, level ice that have not been subject to dynamic deformations show distinct variations in thickness, with significant undulations or troughs in the underside of the sheet. This spatial variability in ice sheet thickness can increase with time as the ice grows, creating localized areas where large volumes of oil trapped under ice could be effectively contained in relatively small areas (Wilkinson et al., 2007). Multiyear ice, which has survived one or more melt seasons, can be highly variable in thickness, with a typical maximum of 3-4 m thickness (Wadhams et al., 2011). Multiyear ice is significantly fresher than first-year ice, without a well-defined network of brine channels (e.g., Johnston, 2004). This has implications for oil migration that are not well understood, although it is generally believed that it may take several seasons for oil trapped under multiyear ice to PREPUBLICATION COPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 31 appear on the surface. Limited field tests with actual oil spilled under multiyear floes provide inconclusive results (Comfort and Purves, 1982). There is a vast historical body of knowledge on the ice environment in the Beaufort Sea, and to a lesser extent in the Chukchi Sea (e.g., Barry et al., 1976; 1979; Kovacs, 1976; Stringer et al., 1980; Dickins, 1984; Reimnitz and Kempema, 1984; St. Martin, 1987; Voelker and Seibold, 1990). Much of this work was completed in the late 1970s and early 1980s, at the peak of the offshore exploration boom in the region. Most reports from that time focus on the morphology and dynamics of fast ice, the shear zone, and seasonal pack ice. Wadhams (2000) and Weeks and Hibler (2010) provide overviews of sea ice knowledge. The Chukchi Sea was the subject of intense study from 1985 to 1990, related to exploration activity and development proposals from a number of companies. In the early 1990s, interest in transporting gas from the North Slope led to a series of comprehensive studies of ice conditions in several locations, including Wainwright. Publicly available sources of modern ice information for the Chukchi Sea are limited in comparison with the Beaufort Sea, partly because of the shorter history of commercial interest. Consequently, fewer historical ice data sets are available; older references include the original Alaskan Sea Ice Atlas (La Belle et al., 1983) and studies of sea ice motion and ice ridging (Weeks et al., 1980; Pritchard and Hanzlick, 1987). Recent industry-sponsored reports are generally proprietary to the operators, although modern ice information is available from researchers at the University of Alaska (e.g. Eicken et al., 2006; Mahoney et al., 2007). Mahoney (2012) notes that the Chukchi and Beaufort Seas have experienced some of the most significant changes in terms of sea ice extent, thickness, and age in recent years (Maslanik et al., 2007; Kwok and Cunningham, 2010). Further discussion of projected changes in timing and extent of sea ice in the Bering and Chukchi Seas is found in Douglas (2010). Summer ice conditions are highly variable and largely dictated by wind patterns. In the Beaufort Sea, persistent easterly winds tend to move the pack away from shore, promoting extensive clearing along the coast, while westerly winds tend to keep the pack ice close to shore and limit the extent of summer clearing (DF Dickins Associates Ltd. and OASIS Environmental, 2006). In recent summers, ice drift in the Beaufort Sea has exhibited a stronger drift component towards the North Pole, moving ice away from the coast (Hutchings and Rigor, 2012; Mahoney, 2012). Hutchings and Rigor (2012) found this to be an important factor leading to the low sea ice extent in summer 2007. The length of the melt season has increased by over 10 days per decade in the Chukchi and Beaufort Seas over the past 30 years (Markus et al., 2009). Over a 12-year period, the duration of summer open water in the Central Chukchi Sea ranged from 8 to 24 weeks (Wang et al., 2012). The average duration of open water in the Chukchi has lengthened significantly on average over the past 30 years. There is also a clear gradation in open water duration with latitude following the retreat of the pack ice edge, from a historical average of 20 weeks or more off Cape Lisburne, to less than 4 weeks north of 72°N. While sea ice extent is at a minimum in the Chukchi-Beaufort region in the latter half of September, ice incursions lasting up to several weeks can occur when the remaining offshore pack ice is driven into shore by sustained westerlies or when remaining thick grounded remnants of the shear (Stamukhi) zone can float free in summer and drift through the region (DF Dickins Associates Ltd. and OASIS Environmental, 2006). The fall transition from the first appearance of new ice to almost complete ice cover (8/10 or more) nearshore occurs rapidly in the Beaufort Sea, often within a week or less. Initial ice growth along the coast can reach 30 cm within two weeks after the first occurrence of new ice PREPUBLICATION COPY

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32 Re esponding to Oil Spills in the U.S. A n Arctic Marine Environme e ent (DF Dick Associa Ltd. et al., 2000). Fa kins ates arther offshor freeze-up is characte re, p erized by the presence of substanti amounts of grease ice (thin layers of clumped crystals on the ocean ial o e s d n surface th can resem an oil slick) or slus before the first consol hat mble s sh e lidated new ice sheet appears. The slush be etween thick floes has been observ to signif ker ved ficantly restr oil spread rict ding in leads, maintaining oil in patch thick eno g hes ough for effe ctive ignitio and burnin (Buist an on ng nd Dickins, 1987). It is importan to understa how the different ice regimes de t nt and e evelop through the winte in er the event that oil rem t maining from an accident release re m tal emains trapp in the ice after freeze ped e e-up. In the wiinter, the Bea aufort Sea pa ice moves in an epis ack sodic, meand dering fashio with a typ on pical net weste drift in response to wind and cur erly r w rrents. Mean monthly ic speeds rea a maxim n ce ach mum in Novem mber and De ecember (typ pically 9-13 km/day) and gradually d k d decrease as th ice pack he thickens and become more cons es solidated throough Januar and Febru ry uary. Mean m monthly speeeds reach a minimum in March and April, with ty m M A ypical values from 3-5 kkm/day, altho ough there a are long periiods (weeks or more) wh the offsh hen hore ice mov very little or meander locally at low ves e rs speeds with no persis w stent sense of direction (Melling and Riedel, 200 Average winter ice drift o ( d 04). e speeds in the Chukch tend to be significantly greater tha in the Bea n hi y an aufort and ca exceed 40 an 0 km/day for 24 hours or more. f Freeze-up alo the Chu F ong ukchi coast begins in earl October o Barrow a progresse ly off and es south to Cape Lisbur by late October. The offshore ice cover in the Chukchi S often tak C rne O e e Sea kes much lon nger to consoolidate, with open water stretching w into Nov h well vember in mmany years. Prevailin easterly to northeaster winds acr ng o rly ross the nort thern Chukch Sea often create an ar of hi n rea open wat between the pack ice and the land ter t dfast ice, wit young ice offshore of the grounde th e f ed perimeter of the land r dfast ice zone along the northern Chu e n ukchi coast ((Figure 2.4). Figure 2.4 Segment of a Moderate Resolution Imagin Spectroradio 4 ng ometer (MODI image from March 18, 20 IS) m 002 showing th Chukchi coa from Cape Lisburne (lowe left) to Point Barrow (uppe right). The b he ast L er t er broad stretch of open f water (dark color) and ne ice along th fast ice edge is a characteri k ew he istic feature of the Chukchi c f coast during mu of uch the winter in response to prevailing east terly winds. So ource: NASA. PREPUB BLICATION C OPY

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Environm mental Cond ditions and Natural Resou N urces in the U.S. Arctic 33 Frequent winter breakawa events ca substantia alter the extent of fas ice along t ay an ally st the Chukchi Sea coast in a matter of hours, as flo that can be several k n f oes kilometers ac cross fracture and e drift out into open wa stretches. In early winter, the fa ice remain unstable r ater w ast ns right into thee coast unt December and occupi a limited extent comp til r ies pared to the Beaufort Sea. In some areas—fo example, north of Wa or ainwright—t fast ice is less than 3 km in width a function of the s h, n the much steeper bot h ttom slope an lack of br nd road shallow shelf area d to the pr w due resence of thhe upper Ba arrow Canyo intersectin the shelf in this region when com on ng i n mpared to the shallower, b but more nar rrow, Beaufo Sea shelf ort f. Sea ice domin nates the Ch hukchi Sea fr rom Novemb to early J ber July on aver rage, four to six weeks sh horter than in the Beaufo Sea. Fast ice begins to breakup in early June, a month ahe n ort o n ead of the Beeaufort Sea. By late June the Chukch Sea is ofte close to ice free, whil the Beauf B e, hi en le fort Sea typiccally remains over 90% ice covered (Eicken et al 2006; Fig s i l., gure 2.5). Us sing satellite imagery from 1996-2 2004, Eicken et al. (2006 determine a mean da of June 4 as the onset of n 6) ed ate t coastal ic breakup, with total cle ce w earing being attained on average by June 18, sev g veral weeks ahead of the Beaufor coast. rt Figure 2.5 MODIS imag showing alm complete ice clearing in the Chukchi Sea by June 25, 2005. In contr 5 ge most i rast, the Beaufo Sea to the ea of Barrow (the most north ort ast ( herly point of l age) is still chok with very close land in the ima ked pack ice. Source: NASA. S . Based on long B g-term ice ch interpre hart etations, mulltiyear ice flo in high c oes concentration ns (5/10 or more) are ra m arely found south of Wai inwright and very rarely south of Point Lay. d Occasionnally, old flo have been observed in low conce oes n entrations sou of Cape Lisburne, bu uth ut the south hern Chukchi Sea is essentially free of old ice thr o roughout the year. Clust of gener e ters rally low conccentrations of old ice (2-3 3/10 on aver rage) can occ for short periods of t cur t time off the northern Chukchi coa from Wa ast ainwright to Barrow. Inv vasions of sig gnificant mu ultiyear ice in nto this coast area occu approxima tal ur ately two to three times p decade. per PREPUB BLICATION C OPY

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50 Re esponding to Oil Spills in the U.S. A n Arctic Marine Environme e ent Population siz and trend for most U.S. Arctic m zes ds U marine mam mmals are pooorly known, , with a few exception The most recent bowh w ns. head populattion estimate (2011) was 16,892, e s increasin by 3.7% per year (Giv ng p vens et al., 2012). Based on recent wwinter migrat tion counts conducte from shore sites in Ca ed alifornia, the gray whale population rranged from 17,820 in 2 m 2007- 2008 to 21,210 in 2009-2010 (Du 2 urban et al., 2013). Both bowhead an gray wha populatio h nd ale ons have recoovered from or are recov vering from overexploita o ation in the 1 1800s and ea 1900s du to arly ue commerc whaling. cial . Figure 2.1 Distribution of walrus, sea lions, and pola bears in U.S Arctic waters. Select locati 11 a ar S. ions discussed in the text are als shown on th map. Map ar corresponds to the red box in Figure 1.1. Data from Ar so he rea s x rctic ERMA, attributed to Audubon Al t laska (Pacific walrus), NOAA (Stellar sea li w A ion), and U.S. Fish and Wild dlife Service (P Polar bear). The most rece populatio estimate for the Beau T ent on f ufort Sea stoc of beluga was from ck as 1992, wh observat hen tions from an aerial survey resulted i an estimat of 19,629 (Harwood e al., n in te et 1996). When adjusted for availab W bility bias, th estimate i he increased to 39,258 anim mals, which m may still be un nderestimate (Allen and Angliss, 2012). More recent surve suggest t the Beau ed eys that ufort Sea belug populatio may be in ga on ncreasing (Ha arwood and Kingsley, 20 013). The po opulation estimate for eastern Chukchi Sea belugas is also outdated and undere C a a d estimated. B Based on survveys from 198 to 1991, Frost et al. (1 89 F 1993) estima a minim populatio size of 1,2 animals. ated mal on 200 . PREPUB BLICATION C OPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 51 When corrected for animals not seen, the estimate increased to 3,710 (Allen and Angliss, 2012). Satellite tracking data (Suydam et al., 2001) showed that the aerial surveys for the Chukchi Sea population of belugas only covered a small portion of their range, so it is likely that the population is considerably larger. Data collected in 2012 by the Alaska Beluga Whale Committee and the National Marine Fisheries Service are currently being analyzed and will provide an updated estimate of population size. The Pacific walrus population was estimated to number about 200,000 animals between 1975 and 1990; however, the estimates were underestimated because they did not adjust for walruses in Russia or under water (Gilbert et al., 1992; Hills and Gilbert, 1994). The results did not provide reliable or consistent data needed for evaluating trends. Using a new approach in 2006, which involved aerial surveys with corrections from thermal imagery and satellite telemetry, the walrus population was estimated at 129,000 (note that the 95% confidence interval = 55,000-507,000) (Speckman, 2011). That estimate was also biased low, as the entire walrus habitat was not surveyed. A repeatable survey technique is needed for more precise understanding of the population size and trends of Pacific walruses. There is no reliable estimate of the Chukchi Sea subpopulation of polar bears, although there have been efforts to develop an aerial survey to obtain a precise and reliable estimate that could be used for monitoring trends (Nielson et al., 2013). The most recent estimate for southern Beaufort Sea polar bears was 1,526 (Regehr et al., 2006). Amstrup (1995) estimated that the Beaufort Sea stock of polar bears increased by 2.4% per year from 1981 to 1992, with a stable population in the 1990s. Based on recent estimates of survival, recruitment, and body size (Regehr et al., 2007), and low growth rates during two years with low ice cover, the Beaufort Sea polar bear population may be declining (Hunter et al., 2007). There is little understanding of population sizes or trends for other species of marine mammals in the Chukchi and Beaufort Seas (Allen and Angliss, 2012, and references within). While rough population estimates may exist for some species, they are not reliable or precise enough to examine trends, evaluate influences from climate change, or estimate population-level damage in the event of an oil spill. Habitat use has primarily been documented by aerial and acoustic surveys and satellite tracking. Aerial surveys provide information on the distribution and habitat selection for bowhead, beluga, and gray whales and other marine mammals (Moore, 2000; Moore et al., 2000; Clarke et al., 2013). Acoustic surveys can monitor marine mammals in ways that aerial surveys cannot, because recording instruments can listen for vocalizations in inclement weather, under the ice, and for long periods of time. A great deal can be learned about distribution (Delarue et al., 2011; Clarke et al., 2013), influences of oceanography (Stafford et al., 2013), disturbances (McDonald et al., 2012), and other aspects of the biology of marine mammals. Extensive acoustic monitoring has occurred in recent years in the Chukchi and Beaufort Seas, especially through the efforts of industry (e.g., LGL Alaska Research Associates et al., 2013). Satellite tracking has provided additional details about the movements of bowhead whales (Quakenbush et al., 2010; Citta et al., 2012), belugas (Richard et al., 2001; Suydam et al., 2001, 2005), spotted seals (Lowry et al., 1998, 2000), walruses (Jay et al., 2012), and polar bears (Garner et al., 1990; Amstrup et al., 2000, 2001). Some progress has been made to tag and track ringed27 and bearded28 seals, although additional data are still needed. 27 See http://www.north-slope.org/departments/wildlife/Ice_Seals.php#RingedSealMovementStudy; accessed October 28, 2013. PREPUBLICATION COPY

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52 Responding to Oil Spills in the U.S. Arctic Marine Environment Because marine mammals are harvested for subsistence, much is known about diet, reproduction, age and growth, body condition, and health status. Hunters have allowed scientists to collect biological samples from harvested animals, and information has been collected on the diets of bowheads (Lowry et al., 2004), belugas (Loseto et al., 2009), seals (Lowry et al., 1980; Quakenbush et al., 2011), and walruses (Sheffield and Grebmeier, 2009). Life history traits are known for bowheads (George, 2009) and belugas (Suydam, 2009) and other marine mammals. Data for a variety of contaminants are available for many species (e.g., O’Hara et al., 1999; Woshner et al., 2001a, 2001b, 2002). There are many concerns about potential impacts from a changing climate—in particular, that rapidly retreating and thinning summer sea ice may have substantial impacts. Some species, such as those that are ice dependent or ice associated, may have adverse population-level reactions to climate changes, while others adapted to subarctic conditions may benefit. Polar bears, ringed seals, and bearded seals, for example, were listed under the Endangered Species Act because of concerns about negative impacts from predicted future impacts to sea ice and snow (including loss of habitat and access to food sources), although other populations may be resilient to changes (Moore and Huntington, 2008). For example, the bowhead population continues to increase despite the dramatic changes in sea ice observed in the past 10-20 years. Other species, such as fin, humpback, and minke whales seem to be increasing in numbers in the Chukchi Sea, probably because of the changing environment. Climate change impacts to marine mammals may occur through habitat changes (Laidre et al., 2008), including less ice and changing prey, changes in timing or distribution of prey populations (Bluhm and Gradinger, 2008), exposure to novel diseases (Burek et al., 2008), and possibly increased predation from killer whales and competition from more southerly populations that are expanding northward (Moore and Huntington, 2008). Another possible change with decreasing and thinning sea ice could be an increase in commercial shipping through the Arctic (Smith and Stephenson, 2013). Projections of increased vessel traffic could lead to acute or chronic impacts from oil or chemical spills, anthropogenic sound, increased entanglement in marine debris, and ship strikes. Shipping is also associated with the introduction of invasive species, predominantly through the exchange of ballast water. Even though there is considerable information about marine mammals in U.S. Arctic waters, there are still significant data needs, many of which are directly related to predicting and assessing possible damages from spilled oil. They include population size and trends, especially for seals, walruses, and polar bears; movements, timing, and habitat use, especially for seals; climate change impacts; health status, including exposure to spilled oil and other contaminants; biomarker data related to exposure to spilled oil and other types of stress; and ability to separate possible impacts of climate change versus spilled oil or other contaminants. Areas of Biological Significance In the Arctic and elsewhere, areas of biological significance have disproportionally high productivity, biodiversity, and rates of change of pelagic and benthic marine life relative to other surrounding areas (Grebmeier et al., 2010). These areas may include places with high primary or secondary productivity, spawning, nesting or calving areas, rearing areas for young animals, migration routes, or feeding areas. In the winter, sea ice habitats are used by polar bears and ice 28 See http://www.north-slope.org/departments/wildlife/Ice_Seals.php#BeardedSeal and http://kotzebueira.org/current_projects3.html; accessed October 28, 2013. PREPUBLICATION COPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 53 seals. In some cases, female polar bears may den on the sea ice. Other animals forage for ice seals, which are polar bears’ primary prey. Some ice seals migrate south to the Bering Sea during winter, but many ringed and bearded seals remain in the Chukchi and Beaufort Seas to feed, give birth, and molt. Areas near leads or polynyas are likely important for seals and bears throughout the winter. In spring, lead systems provide habitat for bears and seals as well as migration corridors for marine mammals (especially bowhead whales and belugas) and marine birds. As spring progresses, leads are the first areas for phytoplankton blooms. Recent research has documented incredibly large ice algae blooms under pack ice in the Chukchi Sea (Arrigo et al., 2012). Primary productivity in those areas is among the highest measured in marine systems. In open water season, nearshore areas are used by a variety of animals. Birds use the habitats for nesting, brood rearing, molting, feeding, and migration stopovers. Marine mammals use specific areas as haulouts for spotted seals and walruses. Belugas can use cobble beaches near Omalik Lagoon, located south of the village of Point Lay, for molting, calving, and feeding. Breaks or passes in the barrier islands, especially in the Chukchi Sea, are also used. Gray whales migrate to the Chukchi Sea in the summer to feed; they can often be found in the shore zone where they appear to rub against the seafloor, possibly in an effort to rid themselves of parasites and barnacles. There are specific geographic areas associated with some animals. Hanna Shoal is an important foraging area for walruses because of the abundant benthos (Figure 2.11; Clarke et al., 2013; LGL Alaska Research Associates et al., 2013). Oceanographic conditions in and adjacent to Barrow Canyon aggregate fish and invertebrate prey (Rand and Loggerwell, 2010) for belugas and bowheads (Figure 2.10). Ledyard Bay is critical habitat for Spectacled Eiders (Figure 2.9), as molting birds aggregate and probably forage there in the later summer and early autumn (Petersen et al., 1999). Some King Eiders and Long-tailed Ducks also use Ledyard Bay for molting, and probably also for foraging (Oppel et al., 2009). The inside barrier islands along the Beaufort Sea coast are molting habitat for Long-tailed Ducks (Lysne et al., 2004) and migration staging areas for Red and Red-necked Phalaropes. Deltas along the Beaufort Sea coast are nesting habitats for geese, particularly Lesser Snow Geese and Brant, and Yellow-billed Loons in some deltas (Ritchie et al., 2000). The Mackenzie and Colville River Deltas, and the nearshore areas between the two, are also important for Arctic cisco, a major focus of the Nuiqsut fish harvest (Figure 2.8; Moulton et al., 2010). The shelf break in the Beaufort Sea is important because belugas aggregate there for feeding (Suydam et al., 2005; Citta et al., 2013). Bowheads may also migrate along the shelf break in the autumn but are more frequently found in shelf areas, influenced by ice concentration (Moore, 2000; Quakenbush et al., 2013). Coastal areas of the Arctic National Wildlife Refuge, which is managed by the USFWS, are important for denning polar bears (Durner et al., 2003). In the Canadian Beaufort Sea area, the Mackenzie River and its delta are especially important for some marine and anadromous fishes, marine birds, and beluga whales (Harwood et al., 2005). Birds and marine mammals reside here in the open water season, but to a lesser degree in the winter with the exception of ringed seals (Stirling et al., 1982; Smith, 1987). In northeastern Russia, Wrangel Island is a vital denning area for Chukchi Sea polar bears, haulout for walruses, and nesting area for Lesser Snow Geese. The northern coast of Chukotka is also an important haulout area for walruses and the nearshore waters of northern Chukotka are important for feeding bowheads (Moore et al., 1995), especially in later summer and autumn, and lagoons and bays are used by staging or molting Steller’s Eiders and other species. PREPUBLICATION COPY

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54 Responding to Oil Spills in the U.S. Arctic Marine Environment To assess changes in areas of biological significance in the western Arctic between the northern Bering Sea and the eastern Chukchi Sea, an international Distributed Biological Observatory (DBO) was formed. The basis of the DBO is repetitive sampling to gain better understanding of biodiversity, areas with high productivity, and rates of change.29 Five locations were selected for annual pilot studies between 2010 and 2013, successfully sampling oceanographic conditions, chlorophyll and nutrients, phytoplankton and zooplankton, benthos, and higher trophic levels along a series of transects. Effects of Oil on Arctic Ecosystems There are no simple ways to anticipate the effects of an oil spill on an ecosystem. The effects may be acute, as observed in mortality events directly following a spill, and/or chronic, as observed in the population trajectory of species over time or through changes in community composition. Dose-response studies and assessments of sublethal effects on individual species can provide insights into the relative sensitivity of various Arctic species to oil, but they are not always designed to replicate environmental conditions encountered by the organisms after a spill. Much of what has been learned about the acute and chronic effects of oil on ecosystems has come from studies of previous spills or from studies of oil exposure in experimental mesocosms. A summary of the acute and long-term effects on fish, marine mammals, and birds from research on some of the major spills, with particular relevance for high-latitude regions, is available (SL Ross Environmental Research Ltd. et al., 2010). The report illustrates the difficulty in attributing long-term ecosystem or species changes to a spill event, especially in the context of other environmental changes. This could be particularly difficult in the Arctic because of rapid rates of climate change and limited information on the effects of oil on Arctic species and ecosystems. However, effects on organisms could continue in environments where oil persists for years, as was observed for some bird species in oiled areas of Prince William Sound after the Exxon Valdez spill. Lower Trophic Levels Many bacterial taxa known to degrade petroleum hydrocarbons are found in the Arctic, and recent experiments confirm that fresh Arctic Ocean water contains bacteria that grow on and degrade Arctic Shelf oil at −1°C (McFarlin et al., 2014). In a study of phytoplankton and zooplankton in a freshwater Arctic lake, Miller et al. (1978) found an initial decrease in primary productivity and a suppressed phytoplankton bloom after a controlled experimental spill, but an increase to pre-spill levels afterward. Zooplankton were greatly reduced after the introduction of oil, which may have led to observed changes in the phytoplankton species composition. Other studies have also shown that marine zooplankton are negatively affected by crude oil (Barnett and Kontogiannis, 1975; Berdugo et al., 1977; Miller et al., 1978). Larval stages appear most sensitive to polycyclic aromatic hydrocarbons that occur in crude oil, with less impact on later stages, although oil can collect in feeding appendages and bioaccumulation of hydrocarbons can affect egg production and reproductive success (Jensen and Carroll, 2010). Anthropogenic activities such as oil spills could lead to multiple stressors with direct or indirect impacts on the benthos (e.g., Blanchard and Feder, 2003; Blanchard et al., 2003, 2010). In a highly focused research project that examined the relative impacts of letting an oil slick 29 See http://www.arctic.noaa.gov/dbo/. PREPUBLICATION COPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 55 make landfall on an Arctic beach versus using dispersants in very shallow water (a few meters), filter-feeding benthic organisms rapidly extracted oil from the water column (Humphrey et al., 1987). Deposit feeders were slower to take up oil, but they continued to accumulate oil for as much as two years. Short-term exposure to dispersed oil resulted in temporary accumulation of hydrocarbons in Arctic invertebrates (Mageau et al., 1987). However, this study was deliberately designed to expose benthic organisms to dispersant concentrations far higher than they might experience in a spill in deeper water, where the dispersed hydrocarbon concentrations may be rapidly diluted. Two other studies have documented impacts on benthic organisms in the Arctic due to hydrocarbons ( Dauvin, 1982; Blanchard et al., 2011). These studies used small-scale, repeated transects, which are necessary to capture acute effects that may be introduced at the larval stage. Effects on Marine Birds Many birds would be vulnerable to spilled oil in the spring lead system, in nearshore areas, or in river deltas during the open water season through direct exposure and contact or through ingestion of oil through preening or consumption of contaminated prey. Because of their importance for resting, molting, feeding, migration, nesting, and/or brood rearing, an oil spill in these areas could have population-level impacts. Effects on Marine Mammals Marine mammals that rely on fur for insulation (e.g., polar bears, sea otters) have shown high sensitivity to hydrocarbons, while those that rely on blubber for insulation will be less sensitive to impacts related to thermoregulation. Other health impacts, such as irritation to skin or eyes, ingestion or exposure to oil, or impacts to prey may be similar among species (Gerarci and St. Aubin, 1990; NRC, 2003). There are some data available on how oil might affect bowhead whales (NRC, 2003), which could be valuable for assessing environmental changes and possibly for evaluating impacts during or after an oil spill. It is important to understand other health factors currently impacting some marine mammals—for example, numerous ringed seals and walruses were found sick or dead in northern and western Alaska in 2011. The unknown disease was characterized by skin lesions around the face, flippers, and tail; lethargy; and respiratory distress. An Unusual Mortality Event was declared for ringed seals and walruses but not other species, although some individuals also showed signs of the disease. Fewer sick animals were seen in 2012 or 2013. The cause (or causes) of this disease is still unknown, although investigations continue.30 Another Unusual Mortality Event was declared for cetaceans in the Gulf of Mexico in February 2010, five weeks prior to the Deepwater Horizon oil spill, and lasted through December 2012. The impact of the spill on bottlenose dolphins is still being investigated as part of the Natural Resource Damage Assessment (NRC, 2013) and could provide valuable information for assessing cetacean exposure and health in the future. 30 See http://www.alaskafisheries.noaa.gov/newsreleases/2011/umedeclaration2011.htm; accessed October 29, 2013. PREPUBLICATION COPY

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56 Responding to Oil Spills in the U.S. Arctic Marine Environment NEW AND ONGOING U.S. ARCTIC RESEARCH In this section, the committee chose to highlight a few new and ongoing research and monitoring efforts that focus on environmental characteristics of the Arctic. Additional research efforts that focus on oil and oil spill response techniques in Arctic conditions are discussed further in Chapter 3. In July 2012, NOAA’s Office of Response and Restoration and several partners initiated an ERMA for the Arctic. ERMA is an online mapping tool that synthesizes a wide variety of data into an interactive map; the aim is to provide assessments and updates of an ongoing situation and improve coordination among responders. Arctic ERMA31 is a partnership between NOAA (Office of Response and Restoration and Office of Ocean and Coastal Resource Management), the Department of the Interior's Bureau of Safety and Environmental Enforcement (BSEE), the Oil Spill Recovery Institute, and the University of New Hampshire's Coastal Response Research Center. Its aim is to improve access to a wide variety of data from Arctic lease areas. ERMA integrates real-time and static datasets into a single map, where data layers can be turned on and off. The map provides visualization of features including real-time physical conditions, geography and topography, critical wildlife habitats, subsistence use areas, oil and gas wells, other infrastructure, and remote sensing and webcam imagery. With an available Internet connection, ERMA can be used during an emergency to visualize the situation and analyze hazards from the field or from a remote location. Ongoing Arctic ERMA efforts include collaborations to obtain high-priority Canadian datasets, continuing to work with Arctic communities, and integrating additional oceanographic and meteorological data (presentation by Amy Merten, NOAA, February 2013). A large range of data types and formats exist for the physical and biological Arctic environment, which presents a challenge for effective and timely integration and assimilation. The Advanced Cooperative Arctic Data and Information Service32 (ACADIS) is a National Science Foundation (NSF)-funded collaboration between NSIDC, the University Corporation for Atmospheric Research, and the National Center for Atmospheric Research that provides data management support for the Arctic community, in particular support for NSF-funded Arctic data collection. ACADIS provides data archival services and is working now to link to other national data centers (including NSIDC remote sensing data) and develop integrated datasets, manage a wide range of data and metadata types, provide better search functionality for data retrieval, and develop protocols for standardized datasets and data visualization tools. All of these elements will improve data assimilation in numerical forecast/trajectory models, and support efforts toward real-time integrated visualization of data necessary for responders. Another NSF-supported initiative, the Arctic Observing Network33 (AON), is an ocean, atmosphere, ice, and land-based observing system of the Arctic environment. AON includes physical, biological, social, cultural, economic, and system studies of the Arctic. The implementation of AON was in part motivated by recommendations in the 2006 NRC report Toward an Integrated Arctic Observing Network to initiate an Arctic Observing Network for the International Polar Year (2007-2008). Data collected under the AON are made publicly available as soon as possible and are not subject to any embargo period, allowing improved access to data 31 See http://response.restoration.noaa.gov/maps-and-spatial-data/environmental-response-management-application- erma/arctic-erma.html. 32 See http://www.aoncadis.org. 33 See http://www.arcus.org/search/aon. PREPUBLICATION COPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 57 for a broad range of users. This coordinated effort will be developed further through U.S. involvement in the Sustaining Arctic Observing Networks34 (SAON) program, an international program of sustained and coordinated pan-Arctic observing and data sharing. Program goals include promoting community-based monitoring efforts and expanding an observing network that can be most effective for a broad range of stakeholders, including communities, policy makers, business, industry, and scientists. BOEM has launched a large number of ecosystem studies over the past several years in both the Chukchi Sea and the Beaufort Sea, with several more proposed for 2015 (BOEM, 2013). These range from nearshore studies of distribution and habitat use of fish and birds to abundance and distribution of polar bears, bowhead whales, and seals. Much of the research consists of comprehensive marine biological studies with supporting oceanographic components, and many include more than one trophic level. There is an emphasis not only on studies of species identification, abundance, and distribution but also feeding and growth, interaction, and environmental influences. These findings are designed to supply benchmark measurements prior to oil and gas development, and they will also provide critical information to track impacts related to climate change. The Chukchi Sea Offshore Monitoring in Drilling Area35 (COMIDA) program is one of the comprehensive research programs funded by BOEM. The study is investigating benthic organisms and sediment characteristics, with a new phase that is focusing on Hanna Shoal. As mentioned earlier, there is also a study identifying fish and invertebrates in the U.S. and Canadian Beaufort Seas, which is being done in conjunction with the Department of Fisheries and Oceans Canada. BOEM and NOAA are also co-sponsoring a study of how endangered whales utilize the Chukchi Sea. Another BOEM-sponsored initiative is investigating the physical properties and currents in the northeastern Chukchi shelf region and exchanges between the Chukchi and Beaufort Seas.36 The results of this study will be important for evaluating oil spill trajectories and could guide development and validation of oil spill trajectory models. The objectives are to quantify circulation pathways from the shallow Chukchi Sea to the deeper Beaufort Sea; quantify transports through Barrow Canyon; examine the relative importance of prevailing wind forcing, the oceanographic pressure head between the Pacific and Arctic oceans, and the influence of the Earth’s rotation in driving the major ocean circulation patterns in the region; understand seasonally changing ocean stratification and how this impacts current systems; and understand processes that transport water between the Chukchi and Beaufort Seas (primarily winds and unstable flow patterns that generate ocean eddies). The Beaufort/Chukchi Seas Mesoscale Meteorology Modeling Study37 is also funded by BOEM. Wind forcing, the main driver of surface ocean currents and sea ice motion, and weather patterns in the Beaufort and Chukchi Seas are being monitored, analyzed, and modeled numerically to evaluate and predict oil spill trajectories and assess potential environmental impacts. Local weather systems and winds are complicated in the Beaufort Sea region because of temperature differences between the land and ocean and the steep terrain changes associated with the Brooks Range to the south. Meteorological buoys are being deployed in the Chukchi Sea, 34 See http://www.arcticobserving.org. 35 See http://www.comidacab.org. 36 See http://dm.sfos.uaf.edu/chukchi-beaufort/background.php. 37 See http://mms-meso.gi.alaska.edu/. PREPUBLICATION COPY

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58 Responding to Oil Spills in the U.S. Arctic Marine Environment atmospheric data are being assimilated into meteorological models, and the mechanisms leading to the formation and dynamics of local weather systems are being investigated. BOEM’s oil spill risk analysis model generates an ensemble of many simulated oil spill trajectories over many years of wind and ocean current data to develop statistics about the risks of an oil spill.38 It is important to note that presently none of the data from the technologies described here are assimilated into the numerical trajectory model used by BOEM.39 For example, as discussed earlier in this chapter, the surface ocean flow over the Chukchi shelf is often not in the direction of the wind because the flow from the Pacific to the Arctic basins is largely driven by the ocean pressure gradient between the two basins. Because surface trajectory models are often forced only by winds or by ocean climatology that is not valid during the time of interest, this key feature of ocean dynamics is not represented. Further significant efforts on model improvement and validation are needed. A dedicated tracer-release study to examine dispersion in the Chukchi Sea is being planned by researchers at the University of Alaska, Fairbanks; this will be interfaced with modeling efforts of NOAA and BSEE. The Office of Naval Research recently initiated two projects (Emerging Dynamics of the Marginal Ice Zone40 and Sea State and Boundary Layer Physics of the Emerging Arctic Ocean41) to study the retreat of sea ice in the Beaufort Sea and the physical mechanisms in the marginal ice zone. An important part of these studies is wave-ice interaction; wave buoys and ice-mounted instruments are being used to measure ice thickness and atmospheric and ocean parameters. In addition to these programs, the European Commission funds basin-wide Arctic projects. Current examples are Arctic Climate Change, Economy and Society,42 which runs from 2011 to 2014, and Ice, Climate, Economics – Arctic Research on Change,43 which runs from 2014 to 2017. Both have observational and modeling components but also include impacts from oil spills in ice. OBSERVING NETWORK NEEDS In an oil spill, early warning is the key to rapid intervention. While efforts to monitor physical processes and ecosystem components are under way (as described in previous sections), there is still a need to bring together disparate data in an integrated fashion. AOOS, AON, and Arctic ERMA have made admirable starts in this effort, but each has a different focus, datasets, stakeholders, and potential or current users. There are also many community-based monitoring programs in Alaska, but they are not well integrated. Existing programs monitor physical conditions (e.g., ocean, ice), species observations (e.g., seabirds, walrus), coastal observations, and water quality and shellfish. Each of these networks has unique data needs and interests in different spatial and timescales. Observing networks in the Arctic are further challenged by very 38 See http://www.boem.gov/Environmental-Stewardship/Environmental-Assessment/Oil-Spill-Modeling/Oil-Spill- Occurence-Rate-for-Oil-Spill-Risk-Analysis-%28OSRA%29.aspx. 39 Peter Winsor, personal communication; see http://www.boem.gov/Environmental-Stewardship/Environmental- Assessment/Oil-Spill-Modeling/Oil-Spill.aspx. 40 See http://www.onr.navy.mil/en/Science-Technology/Departments/Code-32/All-Programs/Atmosphere-Research- 322/Arctic-Global-Prediction/Marginal-Ice-Zone-DRI.aspx. 41 See http://www.onr.navy.mil/en/Science-Technology/Departments/Code-32/All-Programs/Atmosphere-Research- 322/Arctic-Global-Prediction/Sea-State-DRI.aspx. 42 See http://www.access-eu.org/. 43 See http://www.ice-arc.eu/. PREPUBLICATION COPY

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Environmental Conditions and Natural Resources in the U.S. Arctic 59 large distances and areas to cover, a lack of in situ instrumentation, and a lack of sensor integration. An integrated observing network could build on existing networks and efforts, such as AON or AOOS, but could be enhanced with supplemental data from community-based monitoring, in situ instruments, and remote sensing data (discussed further in Chapter 3). To be of value for oil spill response, the network will need to seamlessly interface with marine traffic information systems and monitoring data from oil fields and will need to include comprehensive data on sentinel species such as migratory birds and marine mammals. For local communities, there is need for integrated data networks that can disseminate information needed for subsistence activities, search and rescue, and emergency response. An integrated observing network would also help advance many of the key priorities identified by the Interagency Arctic Research Policy Committee in their 2013-2017 Five-Year Plan (NSTC, 2013). CHAPTER CONCLUSIONS AND RECOMMENDATIONS Conclusion: Anticipated Arctic development and its increased potential for oil spills in the region drive the need to improve understanding of current environmental conditions, as well as possible changes to ecosystem parameters in response to a spill. Critical types of benchmark data for oil spill response in the Arctic include:  Operational near-real-time forecasts and updates of parameters such as winds, waves, ocean currents, ice cover, ice floe size distribution and drift, thickness, as well as derivative products to deliver high-resolution datasets in support of response actions in all weather and seasons;  Real-time met-ocean data from observational platforms (e.g., drilling and production rigs, high-frequency radar, gliders, drifting buoys) to support real-time forecasting and environmental knowledge;  Identification and monitoring of areas of high biological diversity;  Identification of rates of change for key species;  Spatial and temporal distributions and abundances for fish, birds, and marine mammals;  Subsistence and cultural use of living marine resources;  Sensitivity of key Arctic species to petroleum hydrocarbons; and  High-resolution coastal topography and shelf bathymetry. Additional research and development needs include:  Meteorological-ocean-ice forecast model systems with spatial resolution at 1 km or better and 2- to 3-hour temporal resolution in areas around exploration and production platforms, and Integration of traditional knowledge of sea state and ice behavior into the operational forecast environment.    Conclusion: There is a need for a community-based, multiuse observing network in the Arctic that provides long-term, accessible benchmark information (e.g., environmental conditions, local and traditional knowledge, maritime activity) to support oil spill response and other activities. Current Arctic observing networks are fragmented and do not provide a comprehensive regional view. Effort also needs to be devoted to integrating available data from different groups. Such a PREPUBLICATION COPY

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60 Responding to Oil Spills in the U.S. Arctic Marine Environment system could be a collaboration of federal, state, and tribal governments; non-governmental organizations; and maritime and oil/gas industries, and could be organized by IARPC. Conclusion: The release of proprietary monitoring data associated with exploration activities would further increase knowledge of Arctic environmental conditions and baselines. Making industry and government data more freely available and increasing transparency would bolster the public perception of industry-sponsored research, as would publishing such data in peer- reviewed publications. Where appropriate, communities could also release data that they hold regarding important sites for fishing, hunting, and cultural activities. Conclusion: High-quality nautical charting is essential for marine traffic purposes and oil spill response in the Arctic. However, shoreline topographic and hydrographic data are mostly obsolete, with limited tide, current, and water level data and very little ability to get accurate positioning and elevation. A lack of high-quality nautical charts from federal agencies can be attributed to inadequate funding and historical prioritization. Data from sources outside NOAA’s Office of Coast Survey (e.g., other federal agencies, state agencies, academic research vessels, commercial vessels) could help to fill gaps in data collection. While outside data sources may have quality assurance and quality control issues, analysis of such data could provide information on which areas are most in need of updates. Recommendation: High-resolution satellite and airborne imagery needs to be coupled with up-to-date high-resolution digital elevation models and updated regularly to capture the dynamic, rapidly changing U.S. Arctic coastline. Nearshore bathymetry and topography should be collected at a scale appropriate for accurate modeling of coastline vulnerability and storm surge sensitivity. Short- and long-term Arctic nautical charting and shoreline mapping that have been identified in NOAA and USGS plans should be adequately resourced, so that mapping efforts can be initiated, continued, and completed in timescales relevant to anticipated changes. To be effective, Arctic mapping priorities should continue to be developed in consultation with stakeholders and industry and should be implemented systematically rather than through surveys of opportunity. Conclusion: Ice data and charts are critical needs for marine traffic purposes and for oil spill response efforts. Ice thickness, concentration, and extent need to be integrated into operational use. Recommendation: A real-time Arctic ocean-ice-meteorological forecasting system is needed to account for variations in sea ice coverage and thickness and should include patterns of ice movement, ice type, sea state, ocean stratification and circulation, storm surge, and improved resolution in areas of potential risk. Such a system requires robust, sustainable, and effective acquisition of relevant observational data. PREPUBLICATION COPY