Sökning: "Ocean surface currents"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden Ocean surface currents.

1. 1. Retrieval of Ocean Surface Currents and Winds Using Satellite SAR backscatter and Doppler frequency shift

   Författare :Anis Elyouncha; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Doppler centroid analysis; Bayesian inversion; ocean surface winds; Ocean surface currents; synthetic aperture radar; along-track InSAR;

   Sammanfattning : Ocean surface winds and currents play an important role for weather, climate, marine life, ship navigation, oil spill drift and search and rescue. In-situ observations of the ocean are sparse and costly. Satellites provide a useful complement to these observations. LÄS MER

3. 2. Anthropogenic Radionuclides in the Arctic Ocean: Distribution and Pathways

   Författare :Dan Josefsson; Lund Medicinsk strålningsfysik; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; americium; plutonium; iodine; strontium; cesium; Sellafield; Chernobyl; global fallout; currents; shelf; ocean; radioactivity; Arctic; Ecology; Ekologi;

   Sammanfattning : Anthropogenic radionuclide concentrations have been determined in seawater and sediment samples collected in 1991, 1994 and 1996 in the Eurasian Arctic shelf and interior. Global fallout, releases from European reprocessing plants and the Chernobyl accident are identified as the three main sources. LÄS MER

4. 3. Retrieval of ocean surface winds and currents using satellite synthetic aperture radar and infrared radiometry

   Författare :Gisela Carvajal; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; surface currents; infrared radiometry; synthetic aperture radar; surface winds; maximum cross correlation; wind direction;

   Sammanfattning : This thesis focuses on the development, analysis and evaluation of methods for the retrieval of ocean surface winds with synthetic aperture radar (SAR) and surface currents with infrared (IR) radiometer sensors. The SAR wind speed retrievals are based on geophysical model functions using wind directions obtained with two approaches. LÄS MER

5. 4. Sea Surface Current Measurements Using Along-Track Interferometric SAR

   Författare :Anis Elyouncha; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Synthetic aperture radar; Ocean remote sensing; SAR; Along-track InSAR; Sea surface currents;

   Sammanfattning : Ocean currents affect the weather, the climate and the marine ecosystem. Observing ocean currents is important for understanding the upper-ocean layer dynamics and its interaction with the other components of the climate system. In-situ measurements are sparse and their deployment and maintenance is costly. LÄS MER

7. 5. Retrieval of Wind Velocity Vectors Over the Ocean Surface with Spaceborne Synthetic Aperture Radar

   Författare :Gisela Carvajal; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind vector; wind direction; synthetic aperture radar SAR ; CMOD-IFR2; local gradient.; ocean winds; wind speed;

   Sammanfattning : Wind over the ocean (normally defined at 10 meter height) is one of the main parameters affectingsea state, generating waves and driving currents. Wind field maps with large area coverageand high resolution therefore represent valuable information for a wide range of applications such asinformation for shipping, which carries 80% of the world’s trade, oil platforms and other maritime infrastructures,modeling, analysis and validation of weather models, improving performance of sensorsonboard maritime infrastructures, etc. LÄS MER