A new, definitive U.N. report on the world’s forests finds that the rate of deforestation is slowing down — but that its global toll has been immense in the last 25 years.
During that period, says the Food and Agriculture Organization’s 2015 Global Forest Resources Assessment, the world’s forested area declined from 31.6 to 30.6 percent of the Earth’s land surface. This represented a loss of 129 million hectares of forest — equivalent to nearly 500,000 square miles. According to the United Nations, that’s “an area almost equivalent in size to South Africa.”
It’s also nearly two Texases.
Nonetheless, the FAO report notes “a very encouraging tendency towards a reduction in the rates of deforestation and carbon emissions from forests and increases in capacity for sustainable forest management.” Globally, while .18 percent of the world’s forests were vanishing annually in the 1990s, only .08 percent was lost annually from 2010 to 2015.
The average annual loss is the sum of total losses (often from natural forests) and total gains (often from planted forests, or plantations, as well as from restored natural forests). Some 7.6 million hectares are lost annually at present, but 4.3 million are gained, according to the FAO, leaving a net loss of 3.3 million.
Most of the losses were to biodiversity-rich tropical forests, the report found — and South America led the way. From 1990 to 2000, the continent lost 3.5 million hectares of natural forests per year on average, although as deforestation rates declined, especially in Brazil, that decreased to 2.1 million hectares annually over the past five years.
The good news is that more and more, forests are falling under conservation management plans and legal protections.
The data also show that an increasingly large percentage of the world’s forests are plantations, rather than natural forests — 110 million hectares of plantations were added between 1990 and 2015. Such forests now represent 7 percent of the global total. And it is important to note that, just like natural forests, they face major threats —particularly from pests.
As a U.N. meeting in Paris to address global climate change nears, perhaps most striking is what the new report reveals about how forest losses contribute to climate change. The world’s forests store an enormous 296 billion tons (or gigatons) of carbon, says the FAO, but over the last 25 years they gave up 17.4 billion tons worth.
That translates into 2.5 billion tons of carbon dioxide per year. Granted, losses in the past five years are much lower, thanks once again to the declining rate of deforestation.
Still, these data clearly show that deforestation is making global warming worse. And it’s a significant slice of the world’s total emissions, which were 32.3 billion tons of carbon dioxide in 2014, according to the International Energy Agency.
Thus, reducing deforestation rates remains a key weapon for combating global warming — and while the battle may be turning on this front, it definitely is not over.
For instance, in reacting to the report, the World Wildlife Fund forecast that without further action, the world could lose another 170 million hectares of forest over the next two decades.
“Fundamental changes in how we think about forests are needed. And they are needed in the next few years. Not 15 years. Not 20 years. Otherwise, we will continue to lose forests at a rate of eight football fields every 10 seconds,” said Kerry Cesareo, senior director of forests at the World Wildlife Fund, in a statement.
And while the FAO’s numbers are encouraging, scientists say the world’s forests also face a host of new threats brought on climate change, including worsening fire and drought risks.
While the FAO report paints a picture of deforestation over the past 25 years, a recent study in Nature found that it has been much more sweeping over hundreds or thousands of them. The research suggested that the world contains over 3 trillion trees overall, but that that number is 46 percent lower than what existed at the dawn of human civilization.