Elements of a Science Plan for the North Pacific Research Board (2004) / Chapter Skim
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3. Research Themes
3. Research Themes
Pages 32-65
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From page 32... ...
, and site visits to eight Alaskan communities and Seattle, Washington, (Box 1-2) , several broad research themes in the North Pacific, Bering Sea, and Arctic Ocean region were identified: ecosystem states and variabilities; human-induced effects; economic, social, and management research; and forecasting and responding to change.
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From page 33... ...
. Based on this concept, specific regions in which sustained high levels of chlorophyll concentrations exist in the North Pacific and Bering Sea, extending into the Arctic Ocean, are believed to support the abundance of higher trophic levels.
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From page 34... ...
Sea ice is discussed separately because of its critical role in many ecosystems. The North Pacific Mesoscale eddy variability, with spatial scales ranging from tens to hundreds of kilometers, is frequently observed in the Gulf of Alaska along the shelves and slopes (Crawford et al., 1995)
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From page 35... ...
The Bering Sea The throughflow of North Pacific water into the Bering Sea through the eastern Aleutian passages provides a source of fresh water from the Alaskan Coastal Current into the southeastern Bering Sea via the Aleutian North Slope Current. Its direct influence on the southeastern Bering ecosystem is recognized but not fully understood.
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From page 36... ...
interpreted the presence of a subsurface chlorophyll maximum in the middle domain as evidence of transfer of phytoplankton to the benthos and a lack of tight coupling between primary production and copepod grazing. They hypothesized that the fate of production in the southeastern Bering Sea is influenced by water temperature (see also Vidal, 1980; Vidal and Smith, 1986; Townsend et al., 1994)
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From page 37... ...
. Arctic Ocean The northward flow of Pacific water through the Bering Strait provides a significant linkage between the North Pacific-Bering Sea and the Arctic Ocean (see Figure 3-1)
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From page 38... ...
In the Chukchi region, the Siberian Coastal Current transports fresh, cold water from the East Siberian Sea. Maximum (March)
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From page 39... ...
Nonetheless, there remains a lack of fundamental understanding of these regions that for centuries have been used for subsistence harvest by Native communities. Sea Ice Sea ice is possibly the most influential environmental element affecting the ecosystems in the Bering Sea and Arctic Ocean.
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From page 40... ...
Large seasonal and interannual variations in ice cover in the marginal ice zone (MIZ) have been observed from both satellite images and ship observations (winds can change the distribution of sea ice in the Bering Sea and the Arctic Ocean at synoptic time scales, that is, around three to seven days.)
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From page 41... ...
From early spring, solar radiation penetrates both leads and the ice itself, initiating algal production both within and under the ice. Light measurements have shown that the melt ponds act as windows, permitting the transmission of incoming solar radiation through to the underlying sea ice, thus accelerating the melting process and enhancing under-ice primary production.
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From page 42... ...
The ice conditions affect higher trophic levels as well. For example, during cold conditions, predation pressures on age-1 pollock by their major piscine predators -- adult pollock, arrowtooth flounder, and Pacific cod -- were intense (Wyllie-Echeverria and Ohtani, 1999)
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From page 43... ...
Oceanic conditions in the North Pacific are influenced by climatic processes on temporal scales ranging from interannual to interdecadal. Of particular note are two well-known climate phenomena: the El Niño Southern Oscillation (ENSO)
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From page 44... ...
Warming has already had an impact on the northern Alaskan communities that depend on hunting whales and other marine mammals from land-fast sea ice. The recent climate warming reported in the Arctic Ocean beginning the late 1980s through the 1990s resulted in earlier spring seaice melt and longer summers (Smith, 1998; Parkinson, 2000)
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From page 45... ...
By increasing photosynthetic fixation of atmospheric carbon through a reduction of ice cover and by increasing the riverine discharge of carbon, climate warming may profoundly alter biogeochemical fluxes on Arctic shelves, thereby affecting the export of carbon to the pelagic and benthic food webs and to the deep basins where it can be sequestered. Whatever the causes of the observed reduction of Arctic sea ice (anthropogenic or natural variability)
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From page 46... ...
reaching a record high in the late 1980s and early 1990s and then swinging back toward less negative values (decadal variability) in the late 1990s early 2000s,3 a situation that may reverse the present decreasing trend in ice cover extent and thickness.
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From page 47... ...
With the exception of some commercially harvested species, time series of individual species or groups of species have tended to be few and of shorter duration than climate-relevant variables. Nevertheless, such time series are approaching 30-50 years in some cases and are providing fresh insights into the effects of climate and biological variability on ecosystem structure and functioning.
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The following subsections outline some of the research themes that NPRB may wish to fund.
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From page 49... ...
, and their dependence on large-scale weather patterns (e.g., Aleutian Low, Pacific Decadal Oscillation, Pacific North American pattern, Arctic Oscillation) to provide more insight into the linkages between physical properties and marine life; and · long-term measurements of the productivity, abundance, distribution, and diets of selected species or groups of species at different trophic levels.
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From page 50... ...
The NPRB could include statistical, coupled sea ice-ocean, biology-only, regional climate, and coupled biochemical-physical models in both one-dimensional and three-dimensional formulations. One of the main challenges regarding three dimensional models involves resolution of a wide range of spatial and temporal scales.
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From page 51... ...
Given this availability, the NPRB should consider beginning a regional climate modeling study of the Gulf of Alaska-Bering Sea-Alaskan Arctic Ocean that would subsequently be coupled with a predictive ecosystem model. A strong, regional biophysical modeling effort, combined with an observing system for model validation and improvements, would provide significant insights into the operation of the ecosystem and critical guidance for its management.
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From page 52... ...
A relatively recent breakthrough that holds promise for improving understanding of the North Pacific, Bering Sea, and Arctic Ocean ecosystems is the development of unmanned aerial vehicles (UAVs) and autonomous underwater vehicles (AUVs)
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. Fishing Fishing is the human activity that has the greatest impact on both targeted and nontargeted populations in the North Pacific.
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. Questions of preservation, option value,5 and bequest6 are most relevant for fish stocks under heavy pressure, where non-use values7 are an important consideration This is not the case in the North Pacific.
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. Marine mammals listed as endangered or threatened are the Blue whale, the Bowhead whale, the Fin whale, the Humpback whale, the North Pacific right whale, the Sei whale, the Sperm whale, and the Steller sea lion (http://www.fakr.noaa.gov/protectedresources)
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From page 56... ...
. First, species foreign to the North Pacific environment are flushed into the ocean together with ballast water.
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From page 57... ...
Many agencies and private industries would make ideal partners for these undertakings. The NPRB could finance research on shipping and invasive species, including the allegedly harmful effects of shipping, such as waste discharge, the introduction of species through ballast water, and disturbance of marine mammals.
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From page 58... ...
There is thus a need for economic and social research to assess how well existing management regimes are functioning, how they could eventually be improved, and what regimes would be appropriate for those fisheries in which the management regime is at a formative stage. The interrelations between socioeconomic processes and exploitation of resources are complex.
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From page 59... ...
Other Economic and Social Research Issues Fisheries-Dependent Communities One possible consequence of a change in regulation is diversion of fish landings and/or operations of fishing boats away from certain com
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These challenges seem likely to put the social fabric in the subsistence communities under pressure. The research questions emanating from this are how great a threat this is to the subsistence economy and what are its longer-term prospects of viability.
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From page 61... ...
Studying the scale of these changes and their effects on the subsistence economy in both economic and social terms would be a timely piece of social research complementing, for example, research on improving health and living conditions. Commercial Fisheries Commercial fisheries in Alaska face some of the same pressures that the subsistence economy faces.
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From page 62... ...
Recording and evaluating these changes would be an integral part of an evaluation of these management changes. Traditional Knowledge Traditional knowledge can provide important information about marine ecosystems.
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From page 63... ...
This is desirable because some of the effects of recent and pending regulatory changes in the fisheries of the North Pacific may have long-term consequences and also because decisions about future regulatory changes would benefit from a long time series of information covering the period before the new regime was put into effect. The NPRB could finance clearly targeted social research projects with the goal of understanding the processes of social change, especially in small and isolated subsistence and commercial fishing communities.
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Recent advances in climate model physics and in high-performance computer technology may soon allow some of the above issues to be addressed. New components of a climate model, including ocean, sea ice, and atmospheric modules, are being developed, that can take advantage of modern computer power to improve model skill in simulating past and predicting future climate changes.
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From page 65... ...
that are limited by temporal (e.g., sea-ice cover) , spatial (covering large areas)
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