A laser scanning technique is being developed by scientists to 3D map the structure of trees in order to determine the biomass and carbon stocks in forests more accurately than by other methods. Matthew Stock reports.
Using 3D laser scanning technology, scientists can now map the layout of forests to an unprecedented degree of accuracy. The technique will help them more accurately determine carbons stocks in forests. Vital for keeping CO2 out of the atmosphere, forests absorb and store climate-warming carbon while transpiring oxygen. Previously, to find out how much carbon dioxide a tree can hold, it had to be cut down. But a terrestrial laser scanner could provide a less destructive answer. Dr Mathias Disney from University College London says the scanner fires thousands of beams a second to build a picture of tree volume and the density of the wood in the trees. (SOUNDBITE) (English) DR. MATHIAS DISNEY, SENIOR LECTURER IN REMOTE SENSING IN THE GEOGRAPHY DEPARTMENT AT UNIVERSITY COLLEGE LONDON, SAYING: "If you've got the tree volume and the tree density, you can estimate the mass of the trees. And so essentially what you can do is you can use the laser scanning to weigh trees." One 360 degree scan takes about two minutes to complete. Combined with precision photography the data collected can generate a three-dimensional portrait of a forest, accurate to the millimetre. Disney says his collected data could be vital for global policy decisions on emissions control and protecting forests. SOUNDBITE) (English) DR. MATHIAS DISNEY, SENIOR LECTURER IN REMOTE SENSING IN THE GEOGRAPHY DEPARTMENT AT UNIVERSITY COLLEGE LONDON, SAYING: "We're trying to reduce our uncertainty in these carbon stock estimates. Because if we can do that, then we can start to say, yes if you reduce CO2 emissions by this much or they increase by this much a certain fraction of that will be taken up by these forests. And our understanding of what those fractions are will be much better." With further research, scientists hope to find ways of using new measurements of forests to determine how they're responding to climate change, and how they can be monitored.