Laser and Satellite Technology Maps How Much Carbon the Amazon Rainforests Can Hold


Photo via alextorrenegra via Flickr Creative Commons

While we know that deforestation means a loss of carbon storage, it's difficult to quantify just how much carbon can still be stored in what is left of the Amazon rainforest. Standing in the way is both practicality issues (each tree trunk must be measured to estimate its stored carbon) and the cost of accurate accounting. But, ecologist Greg Asner and a team of scientists from the Carnegie Institution, World Wildlife Fund and Peru's Ministry of the Environment were able to utilize laser technology, satellite imagery, and ground surveys to precisely measure the amount of carbon the 11 million acres of tropical forest absorbs and emits. And they did it for the low cost of just $0.03 per acre. The results, published in the Proceedings of the National Academy of Sciences, explains how the team accomplished the feat. Using light imaging and ranging, they were able to fly overhead and create a 3D map of the forest, which shows the size and shape of individual trees. They could then calculate the biomass of the entire forest by using 3D maps of sample sections of vegetation.

According to the New York Times, "The map revealed this lowland Amazon forest in southern Peru contains 395 million metric tons of carbon, and emissions from felled trees reached about 630,000 metric tons per year.

"The method distinguished between emissions from deforestation -- complete clearing for uses such as cattle ranches, mining and agriculture -- versus degradation, which can be caused by selective logging or low-intensity fires. The study found carbon emissions from degradation contributed about a third of total emissions in the region."

Perhaps the most important find is that older, more diverse forest is able to store three times the carbon as secondary growth forest -- making an even stronger case for preserving old growth forests. And all this plays a big factor in a carbon-based economy. As the Times states, "The study found the carbon stock for this region is about a third less than estimated by the Intergovernmental Panel on Climate Change (IPCC). The IPCC's tier-1 estimates are based on one average number assigned to different biomes and as such, the monetary value of the carbon would be discounted if based on the rough default."

The technology and the findings can help countries with healthy rainforests take part in a carbon economy, and financially leverage their biological assets without having to send in logging teams.

As the authors state, "[The] Reduced Emissions from Deforestation and Degradation (REDD)...has the potential to connect carbon emitters with governments positioned to reduce forest carbon losses through monetary compensation. In addition to offsetting emissions, REDD could provide indirect support for biodiversity conservation through reduced habitat loss, thus providing a unique solution to the longstanding tension between conservation interests and other land-use needs in tropical forest regions such as the Peruvian Amazon."

The team's new method for accurately and inexpensively accounting for carbon can help programs like REDD work.

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More on Amazon Rainforests
Amazon Rainforest Near Tipping Point - IPCC Projections of Decline Validated
Half the Amazon Could be Lost by 2050, Says Study
Oil and Gas Exploration Threatens Peruvian Amazon
3 Steps You Can Take to Preserve Rainforest Right Now (and Slow Down the Effects of Climate Change for Everyone Else)

Tags: Carbon Emissions | Environmental Footprint | Forestry

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