Better Forest Data Lends Confidence to Carbon Markets

A study published in Nature Climate Change this week measured both the biomass of different types of tropical forests and the emissions lost via deforestation, providing more accurate data than was previously available, according to lead author Alessandro Baccini. That’s important for creating confidence in nascent carbon markets.

Growing trees store carbon dioxide, but 13 million hectares, or 32 million acres, of forest are razed each year, accounting for a significant portion of annual greenhouse gas emissions, according to scientists. Tropical deforestation, in particular, releases as much as 1.1 billion tons of carbon into the atmosphere each year.

Some forest-rich countries are implementing programs to improve forest management and to help fight climate change by reducing carbon emissions from deforestation.

In 2009, Guyana, in northern South America, took those efforts a step further by pioneering a national program to conserve its forests. With the help of McKinsey & Co., it created an economically rational baseline to measure the value of a standing forest. The idea is to calculate how much money Guyana could earn from going the standard development route of logging and agriculture or ranching, and then convince the developed world to pay at least that much to keep the forests standing, recognizing the monetary value of the forests retaining carbon dioxide. These values might include paying less for sea walls to protect coastal communities from sea level rise, for example, or avoiding economic losses from power shutdowns due to droughts that limit water for power plant cooling.

Guyana’s program is stagnating a bit, as is REDD+, Reducing Emissions from Deforestation and Forest Degradation, a U.N. program that is attempting to set up a policy structure for this type of market.

Nevertheless, this idea, that ecosystem services such as carbon dioxide stored in trees has a value to the world, and therefore to the market, will likely become more viable as the market recognizes the expense of humans trying to recreate these services. And an accurate measurement of what’s actually being sold is key to market confidence. Other hurdles remain, such as independent verification and corruption, but reliable data is a first step.

Yesterday’s study estimated that tropical forests in the Americas store around 118 billion tons of carbon, a fifth more than indicated by the Food and Agriculture Organization (FAO) of the United Nations’ 2010 Forest Resource Assessment (FRA) study.

Using both remote sensing and field data, scientists from Woods Hole Research Center (WHRC), Boston University, and the University of Maryland produced what they claim is the most accurate carbon storage map to date of forests, shrublands, and savannas in the tropics of Africa, Asia, and South America.

Based on the new data, researchers believe that current models, such as a 2010 study in Nature Geoscience, may overestimate the net flux of carbon into the atmosphere due to tropical vegetation loss by 11 to 12 percent. That’s because the researchers’ estimates for biomass densities were significantly higher than the FAO’s.

Previous estimates used ‘average’ biomass densities that may have biased emissions’ estimates. This study used both biomass density and deforestation to assign what the researchers believe to be a more representative carbon density to the forests cleared.

For countries trying to meet their greenhouse gases reporting requirements under the United Nations Framework Convention on Climate Change (UNFCCC), these new data are important. Global measurements of where carbon is accumulating and being lost will be used to better quantify how many carbon credits would be needed to reduce carbon emissions and how to quantify financial rewards.