scholarly journals How the Deep, Cold Currents of the Labrador Sea Affect Climate

Eos ◽  
2017 ◽  
Author(s):  
Emily Underwood
Keyword(s):  
Current Data ◽  
Ocean Current ◽  
Labrador Sea ◽  
Oceanic Circulation ◽  
Data Link

Seventeen years of ocean current data link global atmospheric and oceanic circulation.

scholarly journals Estimates of Ocean Currents Using a Labrador Sea Ice Model

1983 ◽  
Vol 4 ◽  
pp. 141-146
Author(s):  
T. E. Keliher ◽  
J. S. Foley
Keyword(s):  
Current Data ◽  
Ocean Current ◽  
Labrador Sea ◽  
Data Set ◽  
Model Simulations ◽  
Pack Ice ◽  
Ice Drift ◽  
Ice Concentration ◽  
Fast Ice ◽  
Ice Model

Efforts to develop a dynamical model of Labrador pack ice have been hampered by a lack of input data, especially ocean current data. This work reports the results of approaching this problem in another way, where model simulations are used as a basis for adjusting the input currents to obtain agreement with ice drift data. The ice drift data comes from a period in February 1977 when a ship was fast in the northern Labrador pack. Unfortunately, the ship experienced navigation problems and the direct current observations were suspect. The model simulations bear this out indicating that it would have been very unlikely that the observed currents along with the other forcing terms could lead to the observed ice drift. A climatological current data set gave better agreement and was slightly modified to give the best agreement. This improved data set was used for a short sensitivity test of the rheological specifications of the model. It was found that the ice drift tracks were not very sensitive to the linear viscous stress law but were more sensitive to the parameterization used to reduce ice velocities in areas of high ice concentration and fast ice. Further plans are to use a model with a more realistic rheological component in order to assess its importance in estimating currents.

scholarly journals Improvement of Ocean State Estimation by Assimilating Mapped Argo Drift Data

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Shuhei Masuda ◽  
Nozomi Sugiura ◽  
Satoshi Osafune ◽  
Toshimasa Doi
Keyword(s):  
State Estimation ◽  
Current Data ◽  
Global Ocean ◽  
Ocean Current ◽  
Oceanic Circulation ◽  
Synthesis System ◽  
Wind Stress Curl ◽  
Data Synthesis ◽  
Ocean State Estimation ◽  
The Impact

We investigated the impact of assimilating a mapped dataset of subsurface ocean currents into an ocean state estimation. We carried out two global ocean state estimations from 2000 to 2007 using the K7 four-dimensional variational data synthesis system, one of which included an additional map of climatological geostrophic currents estimated from the global set of Argo floats. We assessed the representativeness of the volume transport in the two exercises. The assimilation of Argo ocean current data at only one level, 1000 dbar depth, had subtle impacts on the estimated volume transports, which were strongest in the subtropical North Pacific. The corrections at 10°N, where the impact was most notable, arose through the nearly complete offset of wind stress curl by the data synthesis system in conjunction with the first mode baroclinic Rossby wave adjustment. Our results imply that subsurface current data can be effective for improving the estimation of global oceanic circulation by a data synthesis.

scholarly journals Estimates of Ocean Currents Using a Labrador Sea Ice Model

1983 ◽  
Vol 4 ◽  
pp. 141-146 ◽  
Author(s):  
T. E. Keliher ◽  
J. S. Foley
Keyword(s):  
Current Data ◽  
Ocean Current ◽  
Labrador Sea ◽  
Data Set ◽  
Model Simulations ◽  
Pack Ice ◽  
Ice Drift ◽  
Ice Concentration ◽  
Fast Ice ◽  
Ice Model

Efforts to develop a dynamical model of Labrador pack ice have been hampered by a lack of input data, especially ocean current data. This work reports the results of approaching this problem in another way, where model simulations are used as a basis for adjusting the input currents to obtain agreement with ice drift data. The ice drift data comes from a period in February 1977 when a ship was fast in the northern Labrador pack. Unfortunately, the ship experienced navigation problems and the direct current observations were suspect. The model simulations bear this out indicating that it would have been very unlikely that the observed currents along with the other forcing terms could lead to the observed ice drift. A climatological current data set gave better agreement and was slightly modified to give the best agreement. This improved data set was used for a short sensitivity test of the rheological specifications of the model. It was found that the ice drift tracks were not very sensitive to the linear viscous stress law but were more sensitive to the parameterization used to reduce ice velocities in areas of high ice concentration and fast ice. Further plans are to use a model with a more realistic rheological component in order to assess its importance in estimating currents.

The Application and Antifouling of AEM-RS in Ocean Current Buoy

2013 ◽  
Vol 373-375 ◽  
pp. 739-742
Author(s):  
Guo Hua Zhang ◽  
Shi Xuan Liu ◽  
Bin Miao
Keyword(s):  
Performance Index ◽  
Current Data ◽  
Ocean Current ◽  
Electromagnetic Current ◽  
Resource Exploitation ◽  
Marine Resource ◽  
Ultrasonic Cleaning ◽  
Oceanographic Research ◽  
Rapid Monitoring ◽  
Technical Platform

Equipped with type AEM-RS electromagnetic current meter, the buoy provided effective technical platform for on-site rapid monitoring of the ocean current. Performance index and usage in the ocean current buoy of AEM-RS was introduced. Ultrasonic cleaning method in seawater was developed for preventing AEM-RS from biofouling. Ocean current data can serve for oceanographic research and marine resource exploitation.

scholarly journals Pelagic Sargassum Prediction and Marine Connectivity in the Tropical Atlantic

2020 ◽  
Vol 31 ◽  
pp. GCFI20-GCFI30
Author(s):  
Donald R. Johnson ◽  
James S. Franks ◽  
Hazel A. Oxenford ◽  
Shelly-Ann L. Cox
Keyword(s):  
Surface Current ◽  
Current Data ◽  
Ocean Current ◽  
Tropical Atlantic ◽  
Skill Levels ◽  
Vector Correlation ◽  
Marine Connectivity ◽  
Pelagic Habitat ◽  
Arrival Dates ◽  
High Skill

Since 2011, pelagic Sargassum has experienced extraordinary blooms in the Tropical Atlantic where a system of persistent but seasonally variable currents has retained and consolidated it in large masses. Although beneficial at sea, principally as a unique pelagic habitat, when Sargassum inundates the nearshore environment it can have catastrophic effects on tourism, fisheries, health, and local ecosystems. Providing advanced warning of arrival dates of large masses of Sargassum is critical for enabling preparations and planning for its removal, use, and mitigation. Predictions of arrival time and location involve satellite identification of Sargassum at sea together with ocean current data for forward model tracking. However, forecast ocean current data are generally valid for only 5—7 days. In this study, ocean currents from 2 models (HYCOM and OSCAR) are validated against satellite tracked drifters from the Global Drifter Program with vector correlation and with skill in replicating a drifter pathway. Various wind additions to the models are also tested. Although both models capture the surface current systems in the Tropical Atlantic, they are mediocre in performance along both boundaries. In contrast, a drifter based current data model with 0.5% wind addition had high skill levels. This skill—tested drifter—based model was then used to determine marine connectivity across the Tropical Atlantic and suggests a much broader spread of Sargassum in the eastern Tropical Atlantic than is presently observed by satellites, conforming to earlier hypotheses. This model forms the basis for seasonal scale Sargassum forecasting.

Sensitivity Mapping – With Flare! An Internet Approach to Environmental Mapping

2003 ◽  
Vol 2003 (1) ◽  
pp. 95-102
Author(s):  
André Laflamme ◽  
Roger J. Percy
Keyword(s):  
Current Data ◽  
Open Architecture ◽  
Ocean Current ◽  
Gis Mapping ◽  
Web Mapping ◽  
Environmental Mapping ◽  
Mapping System ◽  
Ready Availability ◽  
On Line ◽  
The Web

ABSTRACT During emergencies the ready availability of information on the location and vulnerability of resources at risk is crucial to a successful response and in preventing or minimizing further environmental impacts. Environment Canada, Atlantic Region, has developed over a number of years a computer based GIS mapping system for managing and analyzing environmental information. This stand-alone user friendly mapping application has recently moved to the web; allowing broader access by federal, provincial and industry partners in the spill response field. Enhancements have been made that facilitate better coordination and exchange of data among partners. It incorporates a unique shoreline classification system which can be viewed in concert with biological, human use and logistical data. It includes a spill logging function to manage situation reports, maps, resource summaries, photographs and trajectory model outputs. The system allows thematic layers to be displayed on either topographic maps or hydrographic charts and possesses links to other sites that allow real-time display of weather and ocean current data useful in a response. With an open architecture concept the web mapping system is readily modified; partners are able to digitize on-line and to update their own databases shared on the system. Mapped data for the northeastern United States is also included in the package to facilitate joint response to trans-boundary pollution incidents. Although this paper will highlight the unique features of the web mapping application for planning and responding to environmental emergencies, other partners are using the system for conducting environmental assessments, inland management projects, or planning for nuclear emergencies around the globe.

scholarly journals Some Results from a Linear-Viscous Model of the Arctic Ice Cover

1979 ◽  
Vol 22 (87) ◽  
pp. 293-304 ◽  
Author(s):  
W. D. Hibler ◽  
W. B. Tucker
Keyword(s):  
Local Stress ◽  
Ice Cover ◽  
Current Data ◽  
The Arctic ◽  
Ocean Current ◽  
Drift Model ◽  
Time Period ◽  
Ice Drift ◽  
Non Local ◽  
Arctic Ice

AbstractIn order to assess the effect of non-local stress transferral through the ice cover empirically, a linear viscous model (employing both bulk and shear viscosities) is used to predict drift-rates for one Soviet and two U.S. drifting stations over the time period May 1962 to April 1964. The predictions, based on available atmospheric pressure and ocean-current data, are compared to free-drift results and to observed values. The empirical viscosity values giving the best fit to observations show a pronounced seasonal variation that correlates well with the growth rate of thin ice. Drift predictions, especially long-term net drift results, show drift magnitudes and turning angles to be simulated significantly better by a viscous model than by a free-drift model. The effects of steady currents are shown to be small for velocities averaged over days but significant for averages over years.

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