Navigation Links
Envisat captures first image of Sargassum from space


Sargassum seaweed has been detected from space for the first time using optical radiance data from the Medium Resolution Imaging Spectrometer (MERIS) aboard Envisat. The ability to monitor Sargassum globally will allow researchers to understand better the primary productivity of the ocean and better predict climate change. Credit: ESA
Sargassum seaweed, famous in nautical lore for entangling ships in its dense floating vegetation, has been detected from space for the first time thanks to an instrument aboard ESA’s environmental satellite, Envisat. The ability to monitor Sargassum globally will allow researchers to understand better the primary productivity of the ocean and better predict climate change.

Using optical radiance data from the Medium Resolution Imaging Spectrometer (MERIS) aboard Envisat, Dr Jim Gower and Stephanie King of the Canadian Institute of Ocean Sciences and Dr Chuamin Hu of the US University of South Florida were able to identify extensive lines of floating Sargassum in the western Gulf of Mexico in the summer of 2005. "This appears to be the first report of a satellite image of Sargassum," Gower said. "It is usually associated with the area of the North Atlantic known as the Sargasso Sea after the Sargassum encountered there by early explorers. Our observations of Sargassum lines extending over large areas of the Gulf show that in this area and season it represents a significant fraction of marine primary productivity."

Marine primary production is the process by which floating vegetation, such as phytoplankton and seaweed, absorb atmospheric carbon dioxide through photosynthesis and convert it into organic carbon. By absorbing half of the carbon dioxide emitted into the atmosphere, the oceans have a profound influence on climate, making them major areas of interest for climate modellers.

The discovery was made using the MERIS maximum chlorophyll ind ex (MCI) which provides an assessment of the amount of chlorophyll in vegetation to produce detailed images of chlorophyll per unit area. MERIS is uniquely suited for this because it provides images of above-atmosphere spectral radiance in 15 bands, including three bands at wavelengths of 665, 681 and 709 nanometres in order to measure the fluorescence emission from chlorophyll a.

Chlorophyll is the green photosynthetic compound in plants that captures energy from sunlight necessary for photosynthesis. The amount of chlorophyll present in vegetation plays an important role in determining how healthy it is. Accurately monitoring chlorophyll from space, therefore, provides a valuable tool for modelling primary productivity.

"The 709 band used by MERIS is not present on other ocean-colour sensors. It was essential to our detecting Sargassum," Gower said. "The MCI index has allowed us to find so many interesting things, including Sargassum and Antarctic super blooms. It really gives us a new and unique view of the Earth."

Gower and King are now combining data from MERIS with a sophisticated processing algorithm and powerful Grid computing to broaden this new view. The basic principle behind Grid computing is that anything one computer can do, a pool of computers can do faster and better, enabling the solution of massively complex tasks beyond the capabilities of a single machine or local network.

By using Grid technology, Gower and King intend to compute 5-years worth of MERIS data to determine global estimates of Sargassum biomass and its contribution to ocean productivity. "So far, we have found two things (Sargassum and Antarctic superblooms) that have never been seen from space before," said King. "It is really very exciting."
'"/>

Source:European Space Agency


Related biology news :

1. Envisat and ERS-2 reveal hidden side of Hurricane Rita
2. Breath of the dragon: ERS-2 and Envisat reveal impact of economic growth on Chinas air quality
3. Envisat radar surveillance protects endangered prehistoric fish
4. WWF captures first-ever photo of wild rhino on Borneo
5. Science captures the essence of fruit
6. Triple threat polymer captures and releases
7. MITs ocean model captures diversity of underwater forests
8. A genes first kiss sets off that affair known as puberty
9. Love at first smell
10. Worlds largest rainforest drying experiment completes first phase
11. PCRM develops worlds first cruelty-free insulin assay

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


(Date:6/14/2017)... , June 15, 2017  IBM (NYSE: IBM ) is ... tech event dedicated to developing collaboration between startups and global ... June 15-17. During the event, nine startups will showcase the ... in various industries. France ... international market, with a 30 percent increase in the number ...
(Date:5/6/2017)... , May 5, 2017 RAM ... announced a new breakthrough in biometric authentication based ... quantum mechanical properties to perform biometric authentication. These new ... semiconductor material created by Ram Group and its ... entertainment, transportation, supply chains and security. Ram Group ...
(Date:4/17/2017)... Florida , April 17, 2017 NXT-ID, ... technology company, announces the filing of its 2016 Annual Report on ... and Exchange Commission. ... on Form 10-K is available in the Investor Relations section of ... as on the SEC,s website at http://www.sec.gov . ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... LAGUNA HILLS, Calif. , Oct. 11, 2017 ... London (ICR) and University of ... prognostic tool to risk-stratify patients with multiple myeloma (MM), in ... nine . The University of Leeds ... by Myeloma UK, and ICR will perform the testing services ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... compared the implantation and pregnancy rates in frozen and fresh in vitro ... of progesterone and maternal age to IVF success. , After comparing the results ...
(Date:10/10/2017)... (PRWEB) , ... October 10, 2017 , ... San Diego-based ... of its corporate rebranding initiative announced today. The bold new look is part ... as the company moves into a significant growth period. , It will also expand ...
(Date:10/10/2017)... ... October 10, 2017 , ... For the second time ... US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled to Washington, D.C. ... US2020. , US2020’s mission is to change the trajectory of STEM education in ...
Breaking Biology Technology: