Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


MERIS monitoring tracks planetary photosynthesis levels


Daily multispectral observations from Envisat’s MERIS sensor are being combined with a sophisticated processing algorithm and powerful Grid computing to reveal global photosynthesis activity on land. This permits researchers to trace the state of health of terrestrial plant cover, identifying areas under stress and assessing damage from drought or fires.

An algorithm developed by the European Commission’s Joint Research Centre (EC-JRC) in Ispra, Italy is the basis for global monthly photosynthesis maps derived from MERIS imagery. Their production represents a demanding data-processing task only made possible on a routine basis through the Earth Science Grid-On-Demand service available from ESRIN, the European Centre for Earth Observation, in Frascati.

Maps of anomalies in photosynthesis levels over European countries have then been produced by scientists at the Institute for Environment and Sustainability of EC-JRC, based on observations gathered from 1998 to 2002.

Grid-processed results shown here indicate a decrease in vegetation activity against the average for Spain and Portugal, due to unusually cold and dry conditions at the beginning of the year, leading to plant stress. In the past the effects of the 2003 European drought were detected in a similar way, but in the absence of any long-term continental-scale perspective on vegetation growth.

Forget fossil fuels and nuclear plants: on a global scale solar power is the dominant source of energy. Across land and sea, our world’s plant life uses the process called photosynthesis to convert incoming sunlight into chemical energy, along the way producing all the oxygen we breathe.

The fraction of incoming solar radiation useful for photosynthesis that is actually absorbed by vegetation – a value known as the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) – is well-recognised as an indicator of its condition and an influence on its capacity for growth, or ’productivity’. FAPAR has been recognised as a fundamental surface parameter by international organisations including the Global Climate Observing System (GCOS), charged with providing data on the Earth’s climate system.

Vegetation plays a critical role on Earth as all animals and humans ultimately depend on it for food. Plants often provide a local habitat for other species to live in, and constitute a major source of raw materials for human activities. Wood in particular constitutes a critical source of energy storage for a large fraction of humanity which relies on it for heating and cooking. It is especially significant as a ’sink’ of carbon that might otherwise enter the atmosphere as carbon dioxide and hasten global warming.

Envisat’s Medium Resolution Imaging Spectrometer (MERIS) acquires multispectral imagery of the Earth, and is used to monitor the state and evolution of the planetary vegetation cover. In particular the instrument’s standard Level-2 product on land, known as the MERIS Global Vegetation Index (MGVI) provides FAPAR values based on reflected radiation from the Earth’s land surface. EC-JRC is responsible for the processing algorithm that yields the MGVI product.

"It is a complex task to extract the required information from the reflected light MERIS measures," explains Nadine Gobron of EC-JRC. "It requires the development of mathematical tools to minimise the effects due to scattering from atmospheric particles, the presence of soils and the changing geometry of illumination and observation."

The validation of MGVI is in fact an ongoing activity, along with that for a family of related FAPAR algorithms developed by JRC for other satellite sensors, including NASA’s MODIS and SeaWiFS, intended to ensure the availability of a long time series of global products. The latter are essential to assess environmental trends, guide policy making and support sustainable development.

"Considerable efforts are made to evaluate the quality of the MGVI and comparable products," explains Gobron. "This takes place both through inter-comparisons between the products generated by various instruments and by direct comparisons with field measurements. These ongoing efforts involve not only ESA Cal/Val groups but similar international groups including CEOS as well as close collaborations with major research programmes, such as CarboEurope funded by the European Union."

The monthly FAPAR anomaly products are an example of close cooperation between ESRIN and EC-JRC. The products are basically mosaics created from multiple images acquired by MERIS over the course of the month. Handling and processing this much data is extremely demanding in processing power, but ESRIN’s Grid-On-Demand service makes it feasible.

Grid computing takes its name and organising principle from the electricity grid: anything one computer can do, a pool of computers can do faster and better. These machines do not have to be in the same building, country or even continent – they simply have to be linked together. A Grid provides its user with massive amounts of memory and processing power in order to tackle very complex tasks.

ESRIN has taken up Grid computing as a means of supporting its primary task: to archive and distribute an ever growing volume of Earth Observation data. Since the start of this year the Earth Science Grid-On-Demand service has been available to registered users. It allows access to a large amount of data and the swift performance of a wide variety of data processing.

Mariangela D’Acunto | alfa
Further information:

More articles from Ecology, The Environment and Conservation:

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

nachricht Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>