BOGOR, Indonesia (1 June, 2011)_Scientists and policy makers are utilizing the latest technology in aerial and space imagery to access information about forests, aiding the fight against climate change.
One of the biggest challenges for scientists studying tropical forests is quantifying the areas of forest remaining and the deforestation and degradation rates. Forest variation is immense and scientists measuring trees and forests on the ground are unable to accurately upscale their measurements to map large areas.
At a workshop, organized by the Center for International Forestry Research on Bali held in April on Tropical Wetland Ecosystems of Indonesia, remote sensing experts from around the world presented their latest results and new technologies for mapping mangrove and peat forests.
“Traditionally, biologists and botanists, have been studying a few plants or maybe a plot” said Faiz Rahman, a remote sensing expert from Indiana University in a video interview from the workshop, “the only problem with that is, even if you study a plot very well, you cannot just say “this plot is 10 meters by 10 meters, why don’t we multiply by 100 000 and this will find out how this whole delta is doing.””
Rahman is doing remote sensing on mangrove areas in South East Asia, particularly in Indonesia where nearly a quarter of the world’s mangroves exist.
NASA and European Space agencies are using their satellites to map forests and providing the data to scientists to use, much of it free of charge. But remote sensing still has its challenges.
One challenge for large areas says Rahman, is utilizing the right combination of technologies to produce the most accurate results, but also results that can be connected to the on ground field measurements.
“That’s where the mid level remote sensing comes in, like using aircraft or field based transects, and scaling up from the field to the satellite sensor, so you can have a good idea of what is happening in a large area”
Another challenge is cloud cover. Certain satellite sensors have limitations on collecting data through the clouds and some satellites can only record images periodically, so not avoiding clouded days.
“NASA now has satellites,” Rahman explains in the video “that takes images of the earth – almost all of the surface of the earth – every day.”
There are also sensors that can look through cloud like RADAR, as well as newer sensors like LIDAR that can collect 3D data and give information about vegetation height.
Rahman and other remote sensing experts are optimistic about the future, as costs of the technology come down and international collaborations increase.
“Policy makers are getting more informed about the power and ability of remote sensing to give them some of the tools they may use in policy making,” he says.
“I think the cost will not be a big problem. It is still somewhat, but I think it is getting better and easier. There are now more and more good scientists, so I think it is a good time.”