Global Forest Restoration Is Best Solution To Climate Change

Scientists have long known restoring the Earth's rapidly depleting forests remains the best solution to climate change. The biggest unanswered question is "How?"

A first-of-its-kind study led by Dr. Jean-Francois Bastin, its lead author, has quantified how many trees the Earth can support in the event of a global replanting program. It also determines where these new trees could exist and how much carbon dioxide they can store.

The study finds there is potential to increase the world's forest land by a third without affecting cities or agriculture. It says it will be possible to regrow trees over an area the size of the United States or larger than Brazil.

The study provides the first quantitative assessment of the feasibility of global forest restoration targets.

The good news is that once these new trees mature, these new forests can store 205 billion tonnes of COs, or more than two-thirds of the 300 billion tonnes of extra CO2 that exists in atmosphere as a result of human activity since the Industrial Revolution.

Sounds good.

The study also suggests the potential exists to regrow trees in croplands and urban areas. This opens the door to expanding the scope for agroforestry and city trees so these play a major role in fighting climate change.

The study, however, recommends immediate action.

Professor Tom Crowther, senior author of the study and founder of the Crowther Lab, said it's well known restoring forests does play a part in tackling climate change, but scientists have no scientific understanding of what impact this could make.

"Our study shows clearly that forest restoration is the best climate change solution available today and it provides hard evidence to justify investment. If we act now, this could cut carbon dioxide in the atmosphere by up to 25 percent, to levels last seen almost a century ago."

On the other hand, he pointed out it will take decades for new forests to mature and achieve this potential. It is, therefore, most important people "protect the forests that exist today, pursue other climate solutions, and continue to phase out fossil fuels from our economies in order to avoid dangerous climate change."

There are currently 5.5 billion hectares of forest with a total 2.8 billion hectares of tree canopy cover. The UN Food and Agriculture Organization defines a forest as land with at least 10 tree cover and without human activity.

The Crowther Lab finds forests might be regrown on 1.7 billion to 1.8 billion hectares of land in areas with low human activity not currently used as urban or agricultural land. Doing this will add 0.9 billion hectares of tree canopy.

These areas won’t naturally be grasslands or wetlands, but degraded ecosystems that could naturally support some level of tree cover.

The same type of forest is good for both birds and people The same type of forest is good for both birds and people

If cropland and urban areas were included the study finds that forests could be regrown on a further 1.4 billion hectares of land, adding 0.7 billion hectares of tree canopy.

"Our study provides a benchmark for a global action plan, showing where new forests can be restored around the globe,” said Dr. Bastin. “Action is urgent and governments must now factor this into their national strategies to tackle climate change."

The study finds more than half the potential to restore trees can be found in just six countries: Russia (151 million hectares); USA (103 million); Canada (78 million); Australia (58 million); Brazil (50 million); and China (40 million).

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