6 results on '"Maslowski, Wieslaw"'
Search Results
2. Winter Atmospheric Buoyancy Forcing and Oceanic Response during Strong Wind Events around Southeastern Greenland in the Regional Arctic System Model (RASM) for 1990-2010*.
- Author
-
DuVivier, Alice K., Cassano, John J., Craig, Anthony, Hamman, Joseph, Maslowski, Wieslaw, Nijssen, Bart, Osinski, Robert, and Roberts, Andrew
- Subjects
OCEAN-atmosphere interaction ,OCEAN circulation ,WINTER ,WINDS ,BUOYANCY - Abstract
Strong, mesoscale tip jets and barrier winds that occur along the southeastern Greenland coast have the potential to impact deep convection in the Irminger Sea. The self-organizing map (SOM) training algorithm was used to identify 12 wind patterns that represent the range of winter [November-March (NDJFM)] wind regimes identified in the fully coupled Regional Arctic System Model (RASM) during 1990-2010. For all wind patterns, the ocean loses buoyancy, primarily through the turbulent sensible and latent heat fluxes; haline contributions to buoyancy change were found to be insignificant compared to the thermal contributions. Patterns with westerly winds at the Cape Farewell area had the largest buoyancy loss over the Irminger and Labrador Seas due to large turbulent fluxes from strong winds and the advection of anomalously cold, dry air over the warmer ocean. Similar to observations, RASM simulated typical ocean mixed layer depths (MLD) of approximately 400 m throughout the Irminger basin, with individual years experiencing MLDs of 800 m or greater. The ocean mixed layer deepens over most of the Irminger Sea following wind events with northerly flow, and the deepening is greater for patterns of longer duration. Seasonal deepest MLD is strongly and positively correlated to the frequency of westerly tip jets with northerly flow. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
3. The Future of Arctic Sea Ice.
- Author
-
Maslowski, Wieslaw, Clement Kinney, Jaclyn, Higgins, Matthew, and Roberts, Andrew
- Subjects
- *
SEA ice , *CLIMATE change , *OCEANOGRAPHY , *OCEAN circulation - Abstract
Arctic sea ice is a key indicator of the state of global climate because of both its sensitivity to warming and its role in amplifying climate change. Accelerated melting of the perennial sea ice cover has occurred since the late 1990s, which is important to the pan-Arctic region, through effects on atmospheric and oceanic circulations, the Greenland ice sheet, snow cover, permafrost, and vegetation. Such changes could have significant ramifications for global sea level, the ocean thermohaline circulation, native coastal communities, and commercial activities, as well as effects on the global surface energy and moisture budgets, atmospheric and oceanic circulations, and geosphere-biosphere feedbacks. However, a system-level understanding of critical Arctic processes and feedbacks is still lacking. To better understand the past and present states and estimate future trajectories of Arctic sea ice and climate, we argue that it is critical to advance hierarchical regional climate modeling and coordinate it with the design of an integrated Arctic observing system to constrain models. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
4. Impact of Shelf-Basin Freshwater Transport on Deep Convection in the Western Labrador Sea.
- Author
-
McGeehan, Timothy and Maslowski, Wieslaw
- Subjects
- *
CONVECTION (Meteorology) , *HYDRAULICS , *OCEAN circulation , *GEOLOGICAL basins , *FRESH water , *EDDY flux - Abstract
Freshwater exiting the Arctic Ocean through the Canadian Arctic Archipelago (CAA) has been shown to affect meridional overturning circulation and thereby the global climate system. However, because of constraints of spatial resolution in most global ocean models, neither the flow of low salinity water through the CAA to the Labrador Sea nor the eddy activity that may transport freshwater from the shelf to areas of open ocean convection can be directly simulated. To address these issues, this study uses a high-resolution ice-ocean model of the pan-Arctic region with a realistic CAA and forced with realistic atmospheric data. This model resolves conditions in the Arctic Ocean upstream of the Labrador Sea and is coupled to a thermodynamic-dynamic sea ice model that responds to the atmospheric forcing. The major shelf-basin exchange of liquid freshwater occurs south of Hamilton Bank, whereas the largest ice flux occurs in the northwest of the basin. Freshwater flux anomalies entering the Labrador Sea through Davis Strait do not immediately affect deep convection. Instead, eddies acting on shorter time scales can move freshwater to locations of active convection and halt the process. Convection is modulated by the position of the ice edge, highlighting the critical need for a coupled ice-ocean model. Finally, the size of eddies and the short duration of events demonstrate the need for high resolution, both spatial and temporal. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
5. Mass and heat transports in the NE Barents Sea: Observations and models
- Author
-
Gammelsrød, Tor, Leikvin, Øyvind, Lien, Vidar, Budgell, W. Paul, Loeng, Harald, and Maslowski, Wieslaw
- Subjects
- *
OCEAN circulation , *MERIDIONAL overturning circulation , *MASS transfer , *HEAT transfer , *MATHEMATICAL models - Abstract
Abstract: The strait between Novaya Zemlya and Frans Josef Land, here called the Barents Sea Exit (BSX) is investigated using data obtained from a current-meter array deployed in 1991–1992, and two numerical models (ROMS and NAME). Combining the observations and models the net volume flux towards the Arctic Ocean was estimated to 2.0±0.6 Sv (1 Sv=106 m3s−1). The observations indicate that about half of this transport consists of dense, Cold Bottom Water, which may penetrate to great depths and contribute to the thermohaline circulation. Both models give quite similar net transport, seasonal variations and spatial current structures, and the discrepancies from the observations were related to the coarse representation of the bottom topography in the models. Also the models indicate that actual deployment did not capture the main in- and outflows through the BSX. A snapshot of the hydrographic structure (CTD section) indicates that both models are good at reproducing the salinity. Nevertheless, they react differently to atmospheric cooling, although the same meteorological forcing was applied. This may be due to the different parameterisation of sea ice and that tides were included in only one of the models (ROMS). Proxies for the heat transport are found to be small at the BSX, and it can not be ruled out that the Barents Sea is a heat sink rather than a heat source for the Arctic Ocean. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
6. The circulation and variability in the western Arctic Ocean : model results
- Author
-
Dixon, Jeffrey S., Maslowski, Wieslaw, Okkonen, Stephen, and Oceanography
- Subjects
Ocean circulation ,Arctic Ocean ,Modeling ,Oceanography - Abstract
Circulation in the western Arctic Ocean is not well understood. To address some of its outstanding questions, volume transport and property fluxes are investigated using a coupled ice-ocean model of the pan-Arctic region configured at a 1/12-degree and 45-level grid. Results for analyses are from the last 23 years of a 70-year integration forced with realistic 1979-2001 atmospheric data. Velocity at three depth intervals, mean transports and fluxes are investigated to identify the main current pathways and directions. Variability is determined by comparison of results a decade apart. Mean velocity fields describe a climatological circulation pattern that is cyclonic in nature with increased intensity during the late 1980s and early 1990s. The meander through the Chukchi Borderland Pass is the main pathway for boundary flow across the Chukchi Plateau. The northern Chukchi Plateau is modeled as a region of major volume, heat and freshwater transport into the Canada Basin interior. It also appears to be an area of net upward heat transport, which may be available for melting ice. Northward flow along the eastern side of the Northwind Ridge is identified as a mechanism for advection of freshwater from the Chukchi shelves into the interior. http://archive.org/details/thecirculationnd109456244 Lieutenant, United States Navy Approved for public release; distribution is unlimited.
- Published
- 2003
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.