As of January 2017, there were about 11.6 million sqkm of forests worldwide that still fit these criteria. From 2014 to 2016, that area declined by more than 87,000km each year
Earth's intact forests shrank by an area larger than Austria every year from 2014 to 2016 at a 20% faster rate than during the previous decade, scientists said Wednesday as the UN unveiled an initiative to harness the "untapped potential" of the land sector to fight climate change.
Despite a decades-long effort to halt deforestation, nearly 10% of undisturbed forests have been fragmented, degraded or simply chopped down since 2000, according to the analysis of satellite imagery.
Average daily loss over the first 17 years of this century was more than 200sqkm.
"Degradation of intact forest represents a global tragedy, as we are systematically destroying a crucial foundation of climate stability," said Frances Seymour, a senior distinguished fellow at the World Resources Institute (WRI), and a contributor to the research, presented this week at a conference in Oxford.
"Forests are the only safe, natural, proven and affordable infrastructure we have for capturing and storing carbon."
The findings come as the United Nations Development Programme (UNDP) and five major conservation organizations launched a five-year plan, Nature4Climate, to better leverage land use in reducing the greenhouse gas emissions that drive global warming.
"37% of what is needed to stay below 2°C" - the cornerstone goal of the 196-nation Paris Agreement - "can be provided by land," said Andrew Steer, WRI President and CEO.
"But only three percent of the public funding for mitigation goes to land and forest issues - that needs to change," he told AFP.
Beyond climate, the last forest frontiers play a critical role in maintaining biodiversity, weather stability, clean air, and water quality.
Some 500 million people worldwide depend directly on forests for their livelihood.
So-called "intact forest landscapes" - which can include wetlands and natural grass pastures - are defined as areas of at least 500sqkm with no visible evidence in satellite images of large-scale human use.
That means no roads, industrial agriculture, mines, railways, canals or transmission lines.
As of January 2017, there were about 11.6 million sqkm of forests worldwide that still fit these criteria. From 2014 to 2016, that area declined by more than 87,000km each year.
"Many countries may lose all their forest wildlands in the next 15 to 20 years," Peter Potapov, an associate professor at the University of Maryland and lead scientist for the research, told AFP.
On current trends, intact forests will disappear by 2030 in Paraguay, Laos and Equatorial Guinea, and by 2040 in the Central African Republic, Nicaragua, Myanmar, Cambodia and Angola.
"There could come a point in the future where no areas in the world qualify as 'intact' anymore," said Tom Evans, director for forest conservation and climate mitigation at the Wildlife Conservation Society.
"It is certainly worrying."
In tropical countries, the main causes of virgin forest loss are conversion to agriculture and logging. In Canada and the United States, fire is the main culprit, while in Russia and Australia, the destruction has been driven by fires, mining and energy extraction.
Compared to annual declines during the period 2000-2013, Russia lost, on average, 90% more each year from 2014 to 2016.
For Indonesia, the increase was 62%, and for Brazil it was 16%.
The new results are based on a worldwide analysis of satellite imagery, built on a study first done in 2008 and repeated in 2013.