HOME >> MEDICINE >> NEWS
Envisat making first direct measurements of ocean surface velocities

For more than a decade space-based radar instruments have been routinely observing ocean surface phenomena including wind, waves, oil slicks, even the eyes of hurricanes. Now employing the same principle as police speed guns satellite radar has also begun to enable direct measurements of the speed of the moving ocean surface itself.

The oceans that cover 71% of the Earth's surface are constantly in motion. Ocean surface currents can lead to strong interaction with wind and waves, and through the transfer of heat influence the weather. Their dynamic range in the mesoscale is broad, with features such as current eddies and fronts, occurrences of filaments and jets, and wind-driven coastal upwelling or downwelling.

High-resolution surface current observations on a large scale are very difficult, although satellite altimeters permit monitoring of sea level anomalies that are related to surface currents. Sea surface temperature and ocean colour measurements also throw light on ocean circulation pattern and seasonal variations.

However Synthetic Aperture Radar (SAR) instruments such as the ASAR on ESA's Envisat have now been demonstrated to potentially offer a more direct and therefore very valuable source of high-resolution information for oceanographers.

SAR sensors record microwave radar backscatter in order to identify patterns of surface roughness. Indeed, over the ocean these patterns are linked to varying surface winds and currents in particular current shear and varying convergence zones that can focus wave energy, resulting in increased wave steepening and enhanced radar-detectable roughness changes. Unfortunately, interpreting radar images to accurately identify and quantify such signatures has been easier in theory than in practice.

"Due to a general lack of sufficient high-quality in-situ observations, the understanding of how these dynamic features contribute to the complicated surface roughness modulation pattern
'"/>

Contact: Mariangela D'Acunto
mariangela.dacunto@esa.int
39-069-418-0856
European Space Agency
27-Mar-2006


Page: 1 2 3 4 5

Related medicine news :

1. European Space Agencys Envisat captures breath of volcano
2. First greenhouse gas animations produced using Envisat SCIAMACHY data
3. ESA donates mosaic of global images taken by Envisat to United Nations
4. Envisat altimeter watches Pacific for cold tongue of La Niña
5. Envisat sees smoke from Europes worst peacetime fire
6. Breath of the dragon: ERS-2 and Envisat reveal impact of economic growth on Chinas air quality
7. Envisat monitoring China floods as part of Dragon Programme
8. Sleep deprivation can threaten competent decision-making
9. Decision making by the growing elderly population is uncharted territory
10. MRI contrast agent can detect heart attack in the making
11. Grace under pressure: FSU researchers analyze the effects of stress on decision-making ability

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:9/15/2018)... ... September 14, 2018 , ... ShareNote, one of the nation’s ... initiative, "ShareNote Live" September, 17-18, 2018 at the Nopsi Hotel to ensure its ... and functionality in the midst of Louisiana’s Medicaid budget crisis. Lt. General Russel ...
(Date:9/15/2018)... ... September 14, 2018 , ... Last night, ... FY 2019 appropriations for Labor, Health and Human Services and Education (LHHS) and ... Pregnancy Prevention (TPP) Program, and $286.5 million for the Title X Family Planning ...
(Date:9/13/2018)... ... ... The Kelly Foundation awarded $83,000 to Saint John’s Program ... children experiencing homelessness in the Sacramento region. The donation will go towards the ... Saint John’s open after the County of Sacramento decided not to renew its 15-year ...
(Date:9/12/2018)... ... September 12, 2018 , ... De Novo Strategies for Getting Your ... 25, 2018 — 1:30 p.m. – 3:00 p.m. ET, http://www.fdanews.com/denovostrategies , ... granted by the FDA? , What are the best practices to win approval? , ...
(Date:9/12/2018)... ... September 12, 2018 , ... Definitive Healthcare , the leading provider ... golf tournament supporting the Dana-Farber Cancer Institute and the Jimmy Fund. , “It’s ... tournament director. “I’m happy we have such wonderful sponsors and volunteers. The growth we’ve ...
Breaking Medicine News(10 mins):
(Date:9/13/2018)... ... 2018 , ... This September is Centers for Disease Control and Prevention’s ... on how to help prevent food poisoning. According to the CDC, every year, an ... and 3,000 die from eating contaminated food. In support of the campaign, Best Sanitizers ...
(Date:9/13/2018)... ... September 13, 2018 , ... AccentCare, Inc., a nationwide leader ... its regional Texas Home Health operations the largest Texas-based post-acute care provider ... personal care services. , Texas Home Health operations serve all 254 counties in ...
(Date:9/12/2018)... ... September 12, 2018 , ... Patient ... Surveys as part of its Population Engage patient experience suite. Express Surveys ... patients, giving the provider organization a wealth of strategic and tactical knowledge in ...
Breaking Medicine Technology:
Cached News: