How green is my planet?

Feb 15, 2006
Earth from space

Scientists from Bournemouth University and the University of Southampton have devised a new method of examining how much of the earth's surface is covered by vegetation and assessing the state of health of the foliage. The European Space Agency (ESA) has recognised the value of this information which is likely to be a vital tool for researchers examining models of terrestrial productivity, gas exchange and climate change.

Dr Jadunandan Dash from the School of Geography and Visiting Professor Paul Curran of Bournemouth University use data from an instrument called Medium Resolution Imaging Spectrometer (MERIS) on board the world's largest environmental satellite, Envisat.

It measures reflected radiation in visible red and near-infra red wavelengths. This information, in turn, is used in a tool called the MERIS Terrestrial Chlorophyll Index (MTCI), which has been an ESA operational product since 2004.

"This product enables us to hold a mirror up to our planet and observe, on a regular basis, just how healthy it really is," said Professor Paul Curran.

Images taken in March and August clearly show differences in chlorophyll content between the northern and southern hemispheres. In both maps, the tropical rainforests had relatively high MTCI levels, but even in the centre of these forests there is a change in values between March and August.

These global composite images are being produced weekly and monthly by the UK Multi-Mission Product Archive Facility (UK-MMPAF) and are the only available terrestrial chlorophyll products from space.

MTCI combines information on the extent of the planet's green areas along with an assessment of the amount of chlorophyll in the leaves to produce detailed images of chlorophyll content per hectare or other unit area.

Chlorophyll is the molecule in plants which turns leaves green and absorbs sunlight, using its energy to synthesize carbohydrates from carbon dioxide and water. Oxygen is also produced in this process. The amount of chlorophyll in plants plays an important role in determining how healthy they are. The MTCI global composites can be used to estimate relative and land cover and specific chlorophyll content in space and time.

Source: University of Bournemouth

Explore further: An unmanned rocket exploded. So what?

add to favorites email to friend print save as pdf

Related Stories

Whale shark fringe migration

Jul 16, 2014

At the fringe of the whale shark range, the volcanic Azore islands may play an increasing role for the north Atlantic population as sea surface temperatures rise, according to a study published July 16, 2014 in the open-access ...

Lower chlorophyll to boost wheat yields

Jul 11, 2014

Almost five decades ago, a plant breeder proved that the tiny brassica Arabidopsis thaliana has higher overall leaf growth when it produces less chlorophyll.

Recommended for you

Possible bright supernova lights up spiral galaxy M61

1 hour ago

I sat straight up in my seat when I learned of the discovery of a possible new supernova in the bright Virgo galaxy M61. Since bright usually means close, this newly exploding star may soon become visible ...

Fifteen years of NASA's Chandra X-ray observatory

2 hours ago

This Chandra X-ray Observatory image of the Hydra A galaxy cluster was taken on Oct. 30, 1999, with the Advanced CCD Imaging Spectrometer (ACIS) in an observation that lasted about six hours.

Confirming a 3-D structural view of a quasar outflow

2 hours ago

A team of astronomers have observed a distant gravitationally-lensed quasar (i.e., an active galactic nucleus) with the Subaru Telescope and concluded that the data indeed present a 3-D view of the structure ...

Hubble sees 'ghost light' from dead galaxies

17 hours ago

(Phys.org) —NASA's Hubble Space Telescope has picked up the faint, ghostly glow of stars ejected from ancient galaxies that were gravitationally ripped apart several billion years ago. The mayhem happened ...

Cassini sees sunny seas on Titan

18 hours ago

(Phys.org) —As it soared past Saturn's large moon Titan recently, NASA's Cassini spacecraft caught a glimpse of bright sunlight reflecting off hydrocarbon seas.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.