Can't see the wood for the trees? A space probe will

Mission aims to map the forest floor and measure carbon storage levels to help predict the changing climate

- Robin McKie

Scientists are about to take part in a revolutionary mission aimed at creating detailed 3D maps of the world's remotest, densest and darkest tropical forests - from outer space. The feat will be achieved using a special radar scanner that has been fitted to a probe, named Biomass, that will be fired into the Earth's orbit later this month.

For the next five years, the 1.25tonne spacecraft will sweep over the tropical rainforests of Africa, Asia and South America and peer through their dense 40m-high canopies to study the vegetation that lies beneath. The data collected by Biomass will then be used to create unique 3D maps of forests normally hidden from human sight.

Less than 2% of sunlight reaches the forest floor in these regions, yet Biomass will study them in unsurpassed detail from a height of more than 600km. More importantly, the mission will allow scientists to calculate how much carbon is stored in the forests and measure how levels are changing as humans continue to cut down trees in the tropics and increase carbon dioxide levels in the atmosphere.