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Environmental 2 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 understanding 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 bio- logical 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, 25 R02581--Oil Spills.indd 25 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 140° E 160° E 180° 160° W 140° W 120° W 100° W 75° N Arctic Ocean Atlantic Water 70° N East Siberian Sea Wrangel Beaufort Gyre Island Bering Shelf Water Beaufort Sea Siberian Coastal Current Chukchi Sea 65° N Siberia Bering Canada Strait Anadyr Alaska Water 60° N St. Lawrence Island Alaska Coastal Water Bering Sea 0 200 400 55° N Distance (km) Figure 2.1  Water masses and sea ice extent in Bering Strait and Chukchi and Beaufort Seas. SOURCE: Grebmeier (2012). 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. (2013b) 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. (2013a) 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 of 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) (Okkonen and Weingartner, 2003). Of utmost importance to oil spill response is the rapid variability of the wind-forced surface ocean circulation. High-frequency radar systems in the Chukchi Sea, which map surface ocean cur- 26 R02581--Oil Spills.indd 26 7/17/14 11:15 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic rents, indicate complex flow patterns that can reverse direction in a matter of hours and can vary significantly in both magnitude (0-85 km/day) and direction over spatial scales of less than 10 km. The Arctic Ocean is strongly stratified, with a fresh, low-density mixed layer up to 40 m deep in the Beaufort Sea. In the summer, very fresh, warm mixed layers only a few meters deep are observed in parts of the Chukchi and Beaufort Seas (e.g., Toole et al., 2010; Weingartner et al., 2013b). This stratification has important implications for the pathways and fate of spilled oil. In the Deepwater Horizon spill, oil plumes rising through the stratified ocean water column spread out at some level of neutral buoyancy and became trapped at depth (Socolofsky et al., 2011). The impact of the strong Arctic Ocean stratification on the subsurface evolution of spilled oil, particularly when surfactants are used (e.g., Adalsteinsson et al., 2013), is an important response planning consideration, as oil that is trapped at depth will not be transported by surface circulation. For this reason, there is a need for characterization and monitoring of Beaufort and Chukchi subsurface circulation, which can be as complex as the surface flow and can be in opposing directions (e.g., Weingartner et al., 1998; Proshutinsky et al., 2009; Morison et al., 2012). Contaminants residing either in the surface or in the subsurface ocean are subject to redis- tribution by coastal ocean upwelling and downwelling events; such events have been well studied in the Beaufort Sea (see Williams et al., 2006; Schulze and Pickart, 2012; Pickart et al., 2013). Strong easterly winds have been observed to bring warm, salty deep water to shallow 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 kilo- meters) 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 (see, 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 envi- ronments, 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). 27 R02581--Oil Spills.indd 27 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 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 5-year period from 1999 to 2005 (Szymoniak and Devine, 2006). Air temperatures are low through most of the year and exhibit little variability from year to year (Figure 2.2). Stegall and Zhang (2012) analyzed three-hourly North American Regional Reanalysis winds in an in-depth review of wind statistics in the Chukchi–Beaufort Seas and Alaska North Slope region for the period 1979-2009. They found a distinct seasonal cycle, with lowest wind speeds (~2-4 m/s) in May and largest (~9 m/s) in October, with extreme winds (up to 15 m/s) that are most often found in October. An increasing trend in the frequency and intensity of extreme wind events was identified over their study period; 95th percentile winds in October increased from 7 m/s in 1979 to 10.5 m/s in 2009. Wind fields over offshore areas are not always well-captured by coastal station data, which comprise the majority of source data for reanalysis winds. For example, along the North Slope, the significant influence of the Brooks Range in winter and the sea breeze effect from thermal gradients between land, ocean, and ice in summer can lead to stark differences between the coastal and offshore wind regimes. Wind measurements from Pelly Island in the Canadian Beaufort Sea, which may better represent the stronger and more variable Beaufort Sea marine winds than coastal stations to the west (see Manson and Solomon, 2007), recorded peak wind speeds of more than 20 m/s in most months in the period 1994-2008 (Fissel et al., 2009). Wind speed distribution can be used to assess how often a spill response technique such as in situ burning could be used. For example, a general upper wind limit for successful ignition and effective burning in booms or in situ burning is on the order of 10 m/s (Buist et al., 1994). Figure 2.2  Monthly average temperatures at the Barrow Automated Surface Observing System (ASOS) from 1999- 2005. SOURCE: Szymoniak and Devine (2006). 28 R02581--Oil Spills.indd 28 7/17/14 11:15 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic Limited daylight can be a major issue for oil spill response during freeze-up and over the winter. Off the Beaufort coast, the maximum of 21 hours of daylight during the breakup season in August reduces to an average of 11 hours in October. However, in practice, twilight can increase the avail- able operational time beyond the hours of sunrise to sunset. From late November to January there is no daylight. Low-visibility conditions in the Beaufort Sea offshore occur most often during the breakup period in July and August. In contrast, the freeze-up period in October has less likelihood of low visibility (Dickins et al., 2000). The Beaufort Sea wave environment can present a significant challenge to oil spill response. Waves are predominantly generated during the open water season and generally propagate from the east and northeast, although recent analyses suggest sizeable waves now also come from the west (Fissel et al., 2012). For much of the summer ( July to August), the close proximity of sea ice is thought to prevent high sea states from forming. However, since 2001, 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 20101 (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 ma- rine 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. 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 1  See http://www.oceanweather.net/msc50waveatlas. 29 R02581--Oil Spills.indd 29 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 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 instal- lation 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  in situ burning, as a typical wind threshold for successful burn operations is 20 kt (~10 m/s) Limit or less; o  surface dispersant application from vessels and aircraft; Limit o  mechanical recovery operations, such as skimmer deployment and boom containment; Limit 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  boom effectiveness, as wave overtopping leads to loss of contained oil; Limit 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 o  Jeopardize safety on deck from slippery and icy surfaces. • V  isibility that is less than visual flight rules or instrument flight rule minimums (due to weather or season) could o  helicopter landings when cloud ceilings or visibility are below minimum standards set by the Limit Federal Aviation Administration or company policy; and o urtail aerial dispersant spraying; C  o  oil spill monitoring by preventing direct visual observations. Limit • Extreme cold temperatures (less than −35°C) could o  safety on deck, due to effects from wind chill; Impact o  responder safety because of potential for frostbite; Impact 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  helicopter operations, which have a lowest acceptable operating temperature set by operators Limit and manufacturers. 30 R02581--Oil Spills.indd 30 7/17/14 11:15 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic 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 chap- ter. 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 ice2 (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 Ma- rine 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 varia- tions 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 sea- bed 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 winter shearing and movement and breakaway events, where large sections drift away from the fast ice edge in deeper water. These events are more common off parts of the Chukchi coast. Beyond the bottom-grounded land-fast ice zone, floating fast ice extends seaward as the season progresses, until it reaches an outer limit within a shear zone (Eicken et al., 2006; Figure 2.3); this zone of often significantly deformed ice can be highly variable in extent but typically occurs between the 15- and 25-m isobaths (also referred to as the Stamukhi zone in traditional Alaskan references such as Kovacs [1976] and Reimnitz and Kempema [1984]). The stable and relatively smooth nearshore areas of land-fast ice (out to approximately 12 m water depth) are used in the Beaufort Sea along the North Slope to construct winter ice roads that routinely carry heavy equipment in midwinter (Potter et al., 1981; Masterson, 2009). Land-fast ice also serves as an important hunting and traveling platform for Arctic coastal communities, as noted by Mahoney (2012). Drift ice floats freely on the ocean surface without any stable connection to land. Pack ice is drift ice whose concentrations exceed 6/10. The pack can open or close on the order of hours in response to winds and/or ocean currents (Potter et al., 2012). Typical midwinter pack ice drift rates in the 2  See http://nsidc.org/cryosphere/seaice/index.html. 31 R02581--Oil Spills.indd 31 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT Beaufort Sea are on the order of 5 km/day (Melling and Riedel, 2004). Ice drift rates can exceed 50 km/day, based on 80th percentile exceedance values published by Melling et al. (2012) from moor- ings in the Canadian Beaufort Sea. Peak values measured in the same dataset over a 30-minute period reached 1.2 m/s. Even higher short-duration speeds (under 12 hours) are possible along the U.S. Beaufort Sea coast, where the mountain barrier effect of the Brooks Range amplifies offshore east-west winds. The net displacement of ice past a mid-shelf site north of Tuktoyaktuk between mid-October and mid-May was almost 2,000 km in 2007-2008. The actual distance along a drift path, including loops and backtracking, could be larger. 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 (Dickins 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 Figure 2.3  Cross-section of typical Beaufort Sea ice zones. SOURCE: Used with permission from University of Alaska Fairbanks, Geophysical Institute. 32 R02581--Oil Spills.indd 32 7/17/14 11:15 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic 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 sur- face 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 satel- lite 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 dis- tributed 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 9-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 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 33 R02581--Oil Spills.indd 33 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 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 datasets are available; older references include the original Alaska Marine Ice Atlas (LaBelle et al., 1983) and studies of sea ice motion and ice ridging (Weeks et al., 1980; Pritchard and Hanzlick, 1987). Recent industry-sponsored re- ports are generally proprietary to the operators, although modern ice information is available from researchers at the University of Alaska Fairbanks (e.g., Eicken et al., 2006; Mahoney et al., 2007, 2012). 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 toward 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 (Dickins et al., 2000). Farther offshore, freeze-up is characterized by the presence of substantial amounts of grease ice (thin layers of clumped crystals on the ocean surface that can resemble an oil slick) or slush before the first consolidated new ice sheet appears. The slush between thicker floes has been observed to significantly restrict oil spreading in leads, maintaining oil in patches thick enough for effective ignition and burning (Buist and Dickins, 1987). It is important to understand how the different ice regimes develop through the winter in the event that oil remaining from an accidental release remains trapped in the ice after freeze-up. In the winter, the Beaufort Sea pack ice moves in an episodic, meandering fashion with a typical net westerly drift in response to wind and currents. Mean monthly ice speeds reach a maximum in November and December (typically 9-13 km/day) and gradually decrease as the ice pack thickens and becomes more 34 R02581--Oil Spills.indd 34 7/17/14 11:15 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic consolidated through January and February. Mean monthly speeds reach a minimum in March and April, with typical values of 3-5 km/day, although there are long periods (weeks or more) when the offshore ice moves very little or meanders locally at low speeds with no persistent sense of direction (Melling and Riedel, 2004). Average winter ice drift speeds in the Chukchi tend to be significantly greater than in the Beaufort and can exceed 40 km/day for 24 hours or more. Freeze-up along the Chukchi coast begins in early October off Barrow and progresses south to Cape Lisburne by late October. The offshore ice cover in the Chukchi Sea often takes much longer to consolidate, with open water stretching well into November in many years. Prevailing easterly to northeasterly winds across the northern Chukchi Sea often create an area of open water between the pack ice and the landfast ice, with young ice offshore of the grounded perimeter of the landfast ice zone along the northern Chukchi coast (Figure 2.4). Frequent winter breakaway events can substantially alter the extent of fast ice along the Chukchi Sea coast in a matter of hours, as floes that can be several kilometers across fracture and drift out into open water stretches. In early winter, the fast ice remains unstable right into the coast until December and occupies a limited extent compared to the Beaufort Sea. In some areas—for example, north of Wainwright—the fast ice is less than 3 km in width, a function of the much steeper bottom slope and lack of broad shallow shelf area due to the presence of the upper Barrow Canyon intersecting the shelf in this region when compared to the shallower, but narrower, Beaufort Sea shelf. Sea ice dominates the Chukchi Sea from November to early July on average, 4 to 6 weeks shorter than in the Beaufort Sea. Fast ice begins to break up in early June, a month ahead of the Beaufort Sea. Figure 2.4  Segment of a Moderate Resolution Imaging Spectroradiometer (MODIS) image from March 18, 2002, showing the Chukchi coast from Cape Lisburne (lower left) to Point Barrow (upper right). The broad stretch of open water (dark color) and new ice along the fast ice edge is a characteristic feature of the Chukchi coast during much of the winter in response to prevailing easterly winds. SOURCE: NASA. 35 R02581--Oil Spills.indd 35 7/17/14 11:15 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT Because marine mammals are harvested for subsistence, much is known about diet, reproduc- tion, 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; Quaken- bush 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,b, 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 pos- sibly 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 assess- ing 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 produc- tivity, biodiversity, and rates of change of pelagic and benthic marine life relative to other surround- ing areas (Grebmeier et al., 2010). These areas may include places with high primary or secondary 56 R02581--Oil Spills.indd 56 7/17/14 11:16 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic 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 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 Can- yon 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, Wran- gel 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, 57 R02581--Oil Spills.indd 57 7/17/14 11:16 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 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. 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.18 Five locations were selected for annual pilot stud- ies between 2010 and 2013, successfully sampling oceanographic conditions, chlorophyll and nutri- ents, 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 hydro- 18  See http://www.arctic.noaa.gov/dbo/. 58 R02581--Oil Spills.indd 58 7/17/14 11:16 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic carbons 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 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 inges- tion 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 (Geraci 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 59 R02581--Oil Spills.indd 59 7/17/14 11:16 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT investigations continue.19 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. NEW AND ONGOING U.S. ARCTIC RESEARCH In this section, the committee chose to highlight a few new and ongoing research and monitor- ing 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 ERMA20 is a partnership between NOAA (Office of Response and Restoration and Office of Ocean and Coastal Resource Management), the De- partment 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 Service21 (ACADIS) is a National Science Foundation (NSF)-funded collaboration between NSIDC, the University Corporation for Atmospheric Re- search, 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 stan- dardized datasets and data visualization tools. All of these elements will improve data assimilation in 19  Seehttp://www.alaskafisheries.noaa.gov/newsreleases/2011/umedeclaration2011.htm. 20 See http://response.restoration.noaa.gov/maps-and-spatial-data/environmental-response-management-application- erma/arctic-erma.html. 21  See http://www.aoncadis.org. 60 R02581--Oil Spills.indd 60 7/17/14 11:16 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic numerical forecast/trajectory models, and support efforts toward real-time integrated visualization of data necessary for responders. Another NSF-supported initiative, the Arctic Observing Network22 (AON), is an ocean, at- mosphere, 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 AON are made publicly available as soon as possible and are not subject to any embargo period, allowing improved access to data for a broad range of users. This coordi- nated effort will be developed further through U.S. involvement in the Sustaining Arctic Observing Networks23 (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 dis- tribution 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. BOEM has also funded shoreline mapping of the North Slope, as part of the ShoreZone program, to characterize estuarine, intertidal, and nearshore geomorphology (BOEM, 2013). The Chukchi Sea Offshore Monitoring in Drilling Area24 (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 ear- lier, 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.25 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 22  See http://www.arcus.org/search/aon. 23  See http://www.arcticobserving.org. 24  See http://www.comidacab.org. 25  See http://dm.sfos.uaf.edu/chukchi-beaufort/background.php. 61 R02581--Oil Spills.indd 61 7/17/14 11:16 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT 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 Study26 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, 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 trajec- tories over many years of wind and ocean current data to develop statistics about the risks of an oil spill.27 Numerical trajectory models estimate trajectories based on velocity data from observations or circulation models; they do not directly assimilate oceanographic or meteorological data, but rely on the degree to which the data represent real-world conditions. 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 gradi- ent 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 BOEM-funded dedicated tracer-release study to examine dispersion in the Chukchi Sea is being planned by researchers at BOEM and 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 Mar- ginal Ice Zone28 and Sea State and Boundary Layer Physics of the Emerging Arctic Ocean29) 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 oceanic parameters. In addition to these programs, the European Commission funds basinwide Arctic projects. Current examples are Arctic Climate Change, Economy and Society,30 which runs from 2011 to 2014, and Ice, Climate, Economics—Arctic Research on Change,31 which runs from 2014 to 2017. Both have observational and modeling components but also include impacts from oil spills in ice. 26  See http://mms-meso.gi.alaska.edu/. 27  See http://www.boem.gov/Environmental-Stewardship/Environmental-Assessment/Oil-Spill-Modeling/Oil-Spill- Occurence-Rate-for-Oil-Spill-Risk-Analysis-%28OSRA%29.aspx. 28  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. 29  See http://www.onr.navy.mil/en/Science-Technology/Departments/Code-32/All-Programs/Atmosphere-Research-322/ Arctic-Global-Prediction/Sea-State-DRI.aspx. 30  See http://www.access-eu.org/. 31  See http://www.ice-arc.eu/. 62 R02581--Oil Spills.indd 62 7/17/14 11:16 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic 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 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 meteorologica-oceangraphic 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. 63 R02581--Oil Spills.indd 63 7/17/14 11:16 AM

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OIL SPILLS IN THE U.S. ARCTIC MARINE ENVIRONMENT Additional research and development needs include: • Meteorological-oceanographic-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 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 at- tributed 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 64 R02581--Oil Spills.indd 64 7/17/14 11:16 AM

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Environmental Conditions and Natural Resources in the U.S. Arctic 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 oceanographic-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. 65 R02581--Oil Spills.indd 65 7/17/14 11:16 AM

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