The forest of this earth could become a boomerang of life

The forest of this earth could become a boomerang of life

Author: Evke Freya von Ahlefeldt

With global warming, the growth of trees also tends to decrease and their mortality rate to increase. As a result, trees store less carbon

At the same time, the higher the temperature rises, the more the flora (because it is not only trees that produce the vital oxygen for life on earth) breathes up and releases carbon. In the long term, therefore, global warming may challenge the essential role of forests as CO2 reservoirs. This is a vicious circle that many researchers are struggling to find solutions to

Currently, the carbon stock contained in forests remains stable up to a daily temperature of 32°C. Beyond this threshold, this stock is reduced to a minimum. Above this threshold, the stock decreases very sharply. The risk is immense. Researchers at the French research centre CIRAD in Montpellier calculated that tropical forests, found mainly in Latin America, Africa and Asia, currently store the equivalent of a quarter of a century of carbon dioxide emissions.

After the oceans, forests are the world’s second largest carbon store. But the crucial role they have played so far is at the mercy of global warming. If global warming is not kept below 2°C, as set out in the Paris Climate Agreement, the daily temperature in three-quarters of tropical forests will exceed 32°C. This is the limit that these forests can withstand.

Tens of billions of tonnes of CO2

Researchers at the Universities of Leeds and Manchester warn that any further temperature rise will lead to rapid losses of forest carbon in the tropics. If this limit is exceeded, there is a danger that the forests will in turn be converted into carbon emitters, i.e. like industrial plants which are partly responsible for the emissions. The green lungs of our earth could become a boomerang for all life on this earth.

Each additional degree of temperature increase would release 51 billion tonnes of CO2 from the tropical forests into the atmosphere.  By comparison, global carbon dioxide emissions in 2019 were estimated at 43.1 billion tonnes of carbon dioxide, according to the Global Carbon Project at Stanford University.

For this study, more than half a million trees of ten thousand different species were measured in 813 tropical forests in twenty-four countries around the world. The observation and results of this research date back to the last forty years.

Published by the UN in May 2020 to mark World Biodiversity Day: THE STATE OF THE WORLD, draws attention to the decline of the world’s forests.

Since 1990, almost 420 million hectares of forest have been lost in order to reclaim the land for other uses. Although deforestation has slowed over the last three decades, nearly 10 million hectares are still lost to agricultural land every year. Scientists confirm that forest destruction is proceeding at an alarming rate and is a major contributor to biodiversity loss.


– Bruno Hérault, tropical forests researcher at the French research centre CIRAD, Montpellier.

– Global Carbon Project (GCP) of Stanford University – UN report from May 2020: THE STATE OF THE WORLD