This engaging YouTube video features a critical discussion at the Global Climate Tipping Points Conference in Exeter, UK, where host Herb Simmens interviews Rob de Laet and Peter Bunyard, co-authors of the book “Cooling the Climate.” The dialogue centers on their pioneering work linking large-scale ecosystem restoration—especially the recovery of tropical forests like the Amazon—with the reversal of global warming. Both guests share their personal journeys: Rob de Laet recounts his practical reforestation efforts in Brazil and how rapid local ecological recovery inspired broader climate ambitions, while Peter Bunyard reflects on his background in scientific research, the founding of The Ecologist magazine, and decades of work on climate and biosphere interactions.
This video was recorded on July 1st, 2025, and published on July 27th, 2025, and represents the opinions of the discussion participants.
A central focus of the conversation is the “biotic pump” theory, which explains how intact forests help drive regional and global hydrological cycles by powering atmospheric moisture transport and cloud formation. The speakers outline the experimental and theoretical foundations of the biotic pump, referencing key contributions from figures like Anastassia Makarieva, as well as evidence from the Amazon basin. They explain how these natural processes not only sustain rainfall and support ecosystems but, if restored at scale, could actively cool the planet. Their calculations suggest that returning millions of square kilometers of forest and agroforestry to deforested regions worldwide could lead to as much as 1°C of global cooling within two decades—making ecosystem restoration one of humanity’s fastest routes out of the climate crisis.
Throughout the discussion, de Laet and Bunyard emphasize the need for mainstream climate science and policy to recognize the overlooked cooling power of forests—not just their ability to sequester carbon, but their much larger influence through evaporative cooling and energy export to space. The guests advocate for urgent, large-scale restoration financed by modest global investment, describing the planetary benefits and cost-effectiveness of such an approach. The video concludes with a call to viewers to learn more about their book, support restoration initiatives, and join the urgent movement to reverse climate change through nature-based solutions.
Peter Bunyard - PhD, is a British science editor, environmental journalist, and researcher specializing in climate science, rainforest hydrology, and the biotic pump theory. As a founding editor of The Ecologist magazine, he has spent decades exploring how forests shape weather and climate—especially in the Amazon—and advocating for ecosystem restoration as a vital solution to global warming.
Rob de Laet - is a climate strategist, reforestation advocate, and co-author focused on ecosystem restoration in the Amazon. His work emphasizes the critical role of forests and natural processes in reversing global warming and restoring planetary health.
Bru Pearce - The Climate Emergency Forum expresses its gratitude to Bru for recording the video dialogue featured in this production ensuring a high-quality capture of the conversation.
Charles Gregoire - Electrical Engineer, Webmaster and IT prime for FacingFuture.Earth & the Climate Emergency Forum; Climate Reality Leader
Heidi Brault - Climate Reality Leader, BA(Psychology), Library & Information Technician Diploma - Video production and website assistant - Organizer and convener, Metadata technician, COP Team Lead for FacingFuture.Earth and the Climate Emergency Forum.
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