First detailed map of global forest change is focus of Science magazine report

Woods Hole, Mass. – A multi-organizational team of scientists has created the first detailed map of global forest change from 2000 through 2012. Woods Hole Research Center Senior Scientist Scott Goetz is a co-author of this week’s Science magazine lead article, entitled “High-Resolution Global Maps of 21st-Century Forest Cover Change,” which details the achievement of the first global quantification of forest extent, loss and gain due to human and natural causes.


Detail of global forest change map.

The report, published online on November 14, 2013, documents a global loss of 888,000 square miles and a global gain of 309,000 square miles of new forest. Among the team’s findings were the successful efforts of the Brazilian government in reducing deforestation in the Amazon, where annual forest loss has decreased by half over the past decade. Conversely, they found that Indonesia doubled its forest loss over the same time period.

“This is an unprecedented view of how forests have changed globally over the past 12 years,” according to Dr. Goetz. “For the first time, we have the detailed information needed to study the impacts of those changes on biodiversity, the carbon cycle, water resources and many other natural processes that depend on forests.”

Led by the University of Maryland’s Professor of Geographic Sciences Matthew Hansen, the team included fifteen researchers from independent institutions, universities, the US government and Google Earth Engine. Until now, most countries have not had the ability to view their trends in forest change. Now, says Prof. Hansen, “with our global mapping of forest changes, every nation has access to this kind of information,” thus making it possible to use the information in policy formulation and implementation to slow deforestation.

More than 650,000 images from NASA’s Landsat 7 satellite were processed to create the final fine resolution (30 meter) maps. The study and resulting maps would have been a fifteen-year undertaking before the advent of Google Earth Engine’s cloud computing capabilities. The mapping database, which quantifies all forest disturbances, whether due to logging, fire, disease or storms, will be updated on an annual basis.

The global forest change maps are at:

Full citation for the Science article: Hansen, M.C., P. V. Potapov, R. Moore, M. Hancher, S.A. Turubanova, A. Tyukavina, D. Thau, S.V. Stehman, S.J. Goetz, T.R. Loveland, A. Komardeey, A. Egorov, L. Chini, C.O. Justice, and J.R.G. Townshend. 2013. High-Resolution Global Maps of 21st-Century Forest Cover Change. Science 342(6160):850-853. doi: 10.1126/science.1244693

WHRC is an independent research institute where scientists investigate the causes and effects of climate change to identify and implement opportunities for conservation, restoration and economic development around the globe.