|Title||PIs||CoPI(s)||Other Project Members||Start Date||End Date||Abstract||Programs||Funding Agency||Implementation Categories||Keywords||Region||Grant/Project Funding Amount||Project Identifer(s)||Project Web Link||Weblink to data and/or metadata||Outreach/Education Description|
|UpTempO: Measuring the Upper Layer Temperature of the Arctic Ocean|
Michael Steele (firstname.lastname@example.org)
Ice-based buoys exist that can measure temperature profiles, but these are not optimized for observing the open sea. Thus the objective of this proposal is to fill this gap in the Arctic Observing Network measurement strategy, i.e., to measure the time history of summer warming and subsequent fall cooling of the seasonally open water areas of the Arctic Ocean. The PIs will focus on those areas with the greatest ice retreat, i.e., the northern Beaufort, Chukchi, East Siberian, and Laptev Seas. Their method will be to build up to 10 relatively inexpensive ocean thermistor string buoys per year, to be deployed in the seasonally ice-free regions of the Arctic Ocean. The Arctic-ADOS (Autonomous Drifting Ocean Station) buoy will float at the ocean surface, equipped with (i) a sea level pressure sensor, (ii) a 50 m long string of 11 thermistors, and (iii) a high precision conductivity/temperature pair at 5 m depth on some buoys for thermistor calibration. Data will be recorded every 2 hours and downloaded in near real time via ARGOS satellite to the web site of the International Arctic Buoy Program (IABP). Daily average and vertically interpolated data (to 1 m bins) will also be provided on the IABP website, and will be sent to data archives (CADIS and NODC). The PIs will also work with scientists at mission-oriented agencies to better incorporate ocean surface data into their global products such as Sea Surface Temperature analyses. Real-time data will also be made available to the operational community via the Global Telecommunications System (GTS). Buoy deployment will use existing assets such as C130 aircraft coordinated by the National Ice Center (NIC), ship cruises planned as part of other projects, and springtime ice surveys conducted by other projects and/or by the U.S. Navy north of Alaska.
|Arctic Observing Network||National Science Foundation|
East Siberian Sea
|Storm Climate of the Western Arctic and its Impact on Shelf-Basin Exchange|
Robert Pickart (email@example.com)
It is predicted that one of the consequences of a warmer climate will be an increase in the intensity and frequency of cyclones that influence the arctic domain. This carries with it strong ramifications, including increased precipitation, more severe coastal flooding and erosion, and enhanced transfer of momentum to the pack-ice and the water beneath it. At present it is not well understood how such changing atmospheric conditions would influence the communication between the shelves and the interior Arctic Ocean. There is increasing evidence that wind-forcing is a dominant driver of such exchange, and that the impacts of this forcing involve multiple aspects of the food web. However, wind-forced shelf-basin exchange is not simply a regional phenomenon, but one that involves a mix of time and space scales, including understanding the behavior and evolution of storm systems centered thousands of kilometers away from the areas in question. In addition, the pack-ice significantly modulates the oceanic response. Therefore, it is necessary to address simultaneously different aspects the of the atmosphere-ice ocean system -over a myriad of scale- to understand fully the causes and effects of storm-driven shelf-basin exchange.
This project brings together multiple fields (meteorology, oceanography), disciplines (physics, biochemistry), and tools (atmospheric and oceanic modeling, data analysis) to enhance the understanding of the system-wide nature of wind-driven exchange and its impact on the ecosystem of the interior and coastal Arctic. The oceanic scope is the Chukchi/Beaufort Sea region, but the atmospheric connections extend into the North Pacific, which in this context clearly needs to be considered as part of the arctic system. The project will unfold in three phases. In phase I NCEP reanalysis fields, AMSR-E ice concentration data, and SBI mooring data will be used to investigate the present storm climate, elucidating the conditions (e.g. upper-level atmospheric currents, orography of Alaska, configuration of pack-ice) leading to the strongest upwelling and downwelling. In Phase II detailed case studies of three storm events will be performed using the MIT ocean/ice model, driven by output from the high-resolution WRF atmospheric model, and analyzed in tandem with the SBI physical mooring data and biochemical shipboard data. This will enable the understanding of how regional variations in the wind and ice fields, together with the topography, influence the shelf-basin exchange. Net fluxes of biochemically important properties for each of the storms will be computed, and scaled up to obtain annual fluxes. In Phase III automated cyclone tracking applied to the full NCEP data set, together with historical ice concentration data, will be used to investigate the storm climate and associated upwelling/downwelling over several decades that encompass different climatic regimes. This will allow an assessment of possible impacts of a future warmer climate.
This research will strive to determine what factors dictate the development and evolution of storms that lead to strong shelf-basin exchange, how the distribution of pack-ice modulates this, and the detailed dynamics that accomplish the exchange. Obtaining quantitative estimates of the associated biochemical fluxes will enable us to address the ramifications on the ecosystems of the shelves and central Arctic.
|Shelf-Basin Interactions Project III||National Science Foundation||Understanding Change|
Climatology / Meteorology
|Collaborative Research: Effect of a Warming Climate on Arctic Shelf and Basin Calanus Populations: Implications for Pan-Arctic Ecosystem Dynamics|
Carin Ashjian (firstname.lastname@example.org)
Copepods of the genus Calanus are the keystone pelagic species in Arctic pelagic ecosystems. Ecosystem structure in the Arctic Ocean and marginal seas is significantly influenced by Calanus population dynamics and production that in turn determines the amount of primary production available either for benthic or pelagic food webs. Calanus are an important food source for pelagic fish species such as capelin, herring, pollock, and larval cod. Therefore, it is not surprising that ecosystems that support a high biomass of these large-bodied, lipid-rich copepods also have rich fisheries (e.g. Bering and Barents Seas). Ongoing warming of the Arctic seas due to climate change will have dramatic impacts on the shelf and basin ecosystems, potentially leading to regime shifts or shifts of biogeographic boundaries of the Calanus spp. Such shifts can have dramatic impacts both to the shelf ecosystems and to the exchange of carbon between Arctic shelves and basins. Furthermore, changes in Arctic shelf ecosystem structure and function can cascade up to upper trophic levels including commercially important fish species and marine mammals that in turn can significantly impact both indigenous and world human populations.
Biological-physical coupled models and numerical experimentation will be used to explore the physical and biological factors that control Calanus population dynamics and biogeographic boundaries in the Arctic Ocean and marginal seas, and to investigate the impacts of various climate warming scenarios on the potential for Calanus mediated regime shifts in these systems. The Arctic Ocean Finite Volume Coastal Ocean Model integrated physical model system will be coupled to an individually-based Calanus model and a 4-stage Calanus concentration model. The physical model incorporates the atmosphere, ice, and ocean components of the system and establishes the environmental framework in which the Calanus population dynamics operate. The Chukchi and Barents Seas are similar in many ways yet different in others. The analyses will focus on these two shelf-seas and adjacent basins, however, the results of the analyses will be applicable to Calanus dynamics on all Arctic shelves. Data will be integrated from a wide range of physical and biological data sets, including the SBI program.
|Shelf-Basin Interactions Project II||National Science Foundation||Understanding Change|
|Collaborative Research: Determining the Present and Future Ocean Carbon Dynamics in the Chukchi Sea and Pan-Arctic Ocean: A Contribution to Shelf-Basin Interactions (SBI) Phase III|
S. Bradley Moran (email@example.com)
As a contribution to SBI phase III efforts, it is critical to improve both our understanding of the Arctic Ocean carbon cycle and predictive capabilities for future responses to environ-mental changes. This requires data integration, synthesis, and modeling activities that lead to new system-level understanding of present and future carbon cycling in the Arctic Ocean. A central hypothesis to be tested in this research is that:
H. The physical forcing (e.g., sea-ice, nutrient supply) and biological responses exert fundamentally different controls on the carbon cycle and the rates air-sea CO2 exchange, NCP and export production in the Chukchi Sea compared to other shelves.
This project will compile organic and inorganic carbon data, and rate measurements (e.g., 234Th/238U export) collected during SBI phase II with other hydrographic, biogeochemical and carbon datasets from across the Arctic. Incorporation of these datasets provides a pan-Arctic context for understanding carbon dynamics in the present and under climate change scenarios (e.g., changes in sea-ice melt, river input, stratification, and biological responses). Specific objectives that will test the central hypothesis, include:
Objective 1: Determine stocks of inorganic and organic carbon in the Chukchi Sea and pan-Arctic (including anthropogenic CO2);
Objective 2: Determine rates, including air-sea CO2 gas exchange, net community production, and export production on the Chukchi and other shelves, and in the adjacent Arctic Ocean basin;
Objective 3: Synthesize rates and stocks using carbon mass balance approaches. This effort includes comparative analyses of the Chukchi shelf with other shelves (carbon cycling on inflow versus interior shelves) and anticipated changes in the Arctic carbon cycle. These analyses will advance understanding through collaborative synthesis and modeling efforts, and, national and international coordination through workshop meetings in 2008 and 2010.
|Shelf-Basin Interactions Project II||National Science Foundation||Understanding Change|
|RUSALCA 2004 Stations|
Jackie Grebmeier (firstname.lastname@example.org)
The Russian-American Long-term Census of the Arctic (RUSALCA) is an extensive activity that is being conducted jointly with the Russian Academy of Science (RAS). This field program is built around ship-based cruises to the Bering and Chukchi Sea region that are planned to occur every 4 years. The first of these cruises was in summer 2004. Cruise objectives are to determine the physical and nutrient state of the water column and provide an initial census of key pelagic and benthic biota. Additional field activities may occur between the major cruises utilizing ships of opportunity. Detecting ecological change and relating it to climate change requires a very long time horizon. Fortunately, there have been a few previous studies in the region to provide historical context and there is likely to be data from Russia that has not been made available to the US. Based on the historical data and new observations, it is anticipated that over the next decade, a clear set of relationships between physical environment and ecosystem response will be evident. To the extent possible, these relationships will be tested in climate-ecosystem models.
|Cooperative Institute for Arctic Research||National Oceanic and Atmospheric Administration||Observing Change|
|Nansen-Amundsen Basin Observational System (NABOS)|
Igor Polyakov (email@example.com)
The overall purpose of the project is to provide a quantitative observationally based assessment of circulation, water mass transformations, and transformation mechanisms in the Eurasian (NABOS) and Canadian (CABOS) Basins of the Arctic Ocean.
The major objectives of this project are the following:
To quantify the structure and variability of the circulation in the upper, intermediate, and lower layers of the Eurasian and Canadian Basins;
To evaluate mechanisms by which the Atlantic Water is transformed on its pathway along the slope of the Eurasian and Canadian Basins;
To evaluate the impact of heat transport from the Atlantic Water on ice;
To investigate the strength and variability of the Fram Strait and the Barents Sea branches of the Atlantic Water;
To estimate the rate of exchange between the arctic shelves and the interior in order to clarify mechanisms of the arctic halocline formation;
To evaluate the storage and variability of heat and fresh water, particularly within the halocline of the Canada Basin;
To quantify Pacific water transport, variability, and water-mass transformation mechanisms from the Chukchi Sea shelf toward the Eurasian Basin.
Japan Marine Science and Technology Center
National Oceanic and Atmospheric Administration
National Science Foundation
Office of Naval Research
|Snow and Ice Processes in the Deposition and Fate of Mercury in the Arctic|
Matthew Sturm (SnowHydroAK@gmail.com)
Atmospheric mercury enters the arctic ecosystem through a set of complex atmospheric chemical reactions that require sea ice and leads to provide reactive bromine, low ambient temperatures, and enough sunlight for photolysis. As a consequence, virtually all atmospheric mercury entering the arctic ecosystem is initially deposited in the snow pack, both on land and at sea. Up to one third of this initial deposit is re-emitted to the atmosphere before the snow melts, but the remainder ends up in snow melt run-off. The fate of this water-borne mercury is uncertain and undoubtedly different on land vs. sea ice. Two key unanswered questions are: How much of the elemental mercury initially deposited is converted to toxic methylmercury, and where does this methylmercury ultimately come to rest? Since cryospheric processes related to snow and ice in large measure determine the answers to these questions, this project sets out to study these processes. The processes studied straddle the Arctic Coast, have pan-Arctic significance, and have a direct impact on human and ecosystem health.
The project has experimental and synthesis components. Along a transect from the Chukchi Sea inland to Barrow and Atqasuk, measurements will be taken of reactive bromine and mercury loading in the snow pack. Detailed observations will be made during mercury depletion events and during the snowmelt, comparing and contrasting the fate of mercury on land with that at sea. Post snowmelt samples from tundra, lakes, ice, and terrestrial and marine sediments will be analyzed and used to determine where and how much of the deposited mercury is converted to methyl mercury. Manipulation experiments will be used to better understand how mercury is entrained in the snow pack, and how it is released during the snowmelt. By understanding and modeling the arctic mercury system, the group will assess how the impact of mercury pollution on human and biological systems is likely to be affected by the unprecedented changes in sea ice and snow conditions taking place in the Arctic today.
|Study of the Northern Alaska Coastal System||National Science Foundation|