We have the technology to monitor deforestation for REDD+, and it’s only going to get better, say researchers

  • Researchers with the Woods Hole Research Center and the Center for Global Development write in a new paper that capabilities are in place to track the status of the world’s tropical forests for REDD+.

  • Dr. Scott Goetz, senior scientist at the WHRC and lead author of the paper, told Mongabay in an email that the key components of forest monitoring for REDD+ are satellite- and aircraft-based remote sensing coupled with “good old fashioned field measurements.”

  • A LiDAR instrument planned for the International Space Station will allow for much higher resolution images and hence more accurate carbon stock mapping and land use change monitoring across all of the world’s forests, the authors note in the Environmental Research Letters paper.

Right now in Paris there are discussions taking place about how to protect tropical forests as part of efforts to stop climate change.

The main vehicle by which any climate accord reached at COP21 will likely seek to do that is REDD+, or Reducing Emissions from Deforestation and forest Degradation, a program administered by the UN that is intended to provide funds to tropical forest countries as incentive for developing their economies in ways that don’t cause massive amounts of deforestation.

Much of the funds channeled via REDD+ to developing countries will be in exchange for verified emissions reductions. Because it is a payment-for-performance scheme, the success of REDD+ will depend on the ability to continuously measure and monitor forests and the carbon stocks they represent — an ability that has been questioned in the run-up to the Paris talks.

But in a paper published last week in Environmental Research Letters, researchers with the Massachusetts-based Woods Hole Research Center (WHRC) and the Washington, D.C.-based Center for Global Development (CGD) report that we not only have the technology to properly monitor forests for REDD+, but imminent advances will further strengthen our ability to keep an eye on the state of the world’s tropical forests.

“REDD+ programs rely on the ability to measure emissions from deforestation confidently over large scales and long time periods,” Dr. Jonah Busch of the CGD, a co-author of the paper, said in a statement. “That wasn’t possible when climate diplomats excluded tropical forests from the Kyoto Protocol, but it’s possible now and it’s time to implement REDD+.”

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Borneo rainforest. Photo by Rhett Butler.

Dr. Scott Goetz, senior scientist at the WHRC and lead author of the paper, told Mongabay in an email that the key components of forest monitoring for REDD+ are satellite- and aircraft-based remote sensing coupled with “good old fashioned field measurements.”

LiDAR (which stands for “light detection and ranging”) is a technology that essentially shoots a laser beam from a spaceborne or airborne platform and records the light that bounces back. Goetz explains that LiDAR allows researchers to measure the three-dimensional structure of tree canopies, including their height and the vertical diversity of canopy elements like leaves, twigs, branches and stems.

“When coupled with field measurements, LiDAR lets one accurately estimate total above ground biomass, or forest carbon stocks, which is one of the two terms needed to estimate emissions from deforestation and forest degradation,” Goetz said.

The other term needed for REDD+, he added, is data on the amount, location and timing of deforestation, forest degradation and regrowth — and that data needs to be compiled year after year. The key technologies needed to map those processes are imaging sensors, like Landsat and RaDAR (which stands for “radio detection and ranging”).

“Combining the field-calibrated LiDAR data on forest carbon stocks with the deforestation, forest degradation and regrowth maps allows one to map emissions across entire countries or even the globe, and to do that year after year,” Goetz said.

While these current technologies allow scientists to measure and map the world’s forests and calculate estimates of the carbon emissions from deforestation and forest degradation, new technologies will soon enhance researchers’ capabilities.

A LiDAR instrument planned for the International Space Station will allow for much higher resolution images and hence more accurate carbon stock mapping and land use change monitoring across all of the world’s forests, the authors note in the Environmental Research Letters paper.

“When combined with current data streams and other new missions under development, the way we monitor tropical forests will be revolutionized,” Goetz said in a statement. “It will also allow us to better assess forest growth and recovery, monitor safeguards for the conservation of natural forests, the biodiversity they support, and inform law enforcement and deforestation alert systems.”

In the paper, Goetz and co-authors assess current forest measurement and monitoring capabilities for REDD+ beyond just emissions reporting, including identification of deforestation drivers, attribution of deforestation events, informing deforestation alert systems for law enforcement and monitoring safeguards on conservation of natural forests and their biodiversity.

“In many cases these capabilities are currently operational,” Goetz told Mongabay, “and in many more cases they will be operational in the next few years as new technology advances and techniques are refined.”

In other words, the measurement and monitoring challenges have been overcome. “Decision makers can now readily assess their options for consistent forest monitoring and reporting to the UNFCCC in the context of REDD+,” Goetz said.

CITATION

  • Goetz, S. J., Hansen, M., Houghton, R. A., Walker, W., Laporte, N., & Busch, J. (2015). Measurement and monitoring needs, capabilities and potential for addressing reduced emissions from deforestation and forest degradation under REDD+. Environmental Research Letters, 10(12), 123001. doi:10.1088/1748-9326/10/12/123001
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