Tag Archives: William Moomaw

Mongabay: There’s far less land available for reforestation than we think, study finds

A participant plants local green plants in a park as part of Ethiopia’s Green Legacy Initiative, which aims to plant 7.5 billion trees by the end of the year, at Jifara Ber site, Addis Ababa, Ethiopia, in July 2025. (AP Photo/Amanuel Birhane)

In this story, I had an opportunity to evaluate an increasingly common national strategy of combatting climate change: planting trees. Lots and lots and lots of trees.

I first became familiar with massive tree-planting pledges as a way of fighting climate change at COP20 in Lima, Peru in 2014. The Bonn Challenge promised to reforest 350 million hectares of deforested or degraded land by 2030. The person declaring the great promise of this pledge was Bianca Jagger, the former wife of the Mick Jagger; her environmental nonprofit was an official sponsor of the challenge. It sounded great at the time. It sounded far less great as time went on.

Over the years, the national promises have mounted — to the extent where they became unrealistic if not plain misleading. Rather than do the hard work of reducing emissions and protecting biodiverse forests, countries simply promised to plant more and more trees — often in ecosystems such as savannas and grasslands that would be damaged by such efforts.

The new study in Science that I report on makes clear that there is far less available land for reforestation than imagined. Perhaps more importantly, as forestry expert Bill Moomaw shared with me, there is no shortcut to slowing down the ever-accelerating climate crisis.

Monoculture tree farms do very little to sequester carbon compared to mature, biodiverse forests. They do even less to harbor biodiversity. Here, you see an oil palm plantation (left) and native tropical rainforest on the island of Sumatra in Indonesia. Image by Rhett Ayers Butler/Mongabay.

Mongabay: Success of Microsoft’s ‘moonshot’ climate pledge hinges on forest conservation

Remote sensing through and artificial intelligence are keys to Pachama’s novel strategy for tracking the amount of carbon stored in forests for the purposes of augmenting the market for forest protection and carbon offsets. Photo courtesy Pachama

Here’s my story behind a Silicon Valley startup up with enormous ambitions when it comes to climate mitigation with a global client to match its lofty goals.

In mid-January, Microsoft made an astonishing pledge: a company that now emits 16 metric tons of greenhouse gases annually would become carbon negative by 2030, and by 2050, zero out all of the emissions it ever put up into the atmosphere since the company was founded by Bill Gates and Paul Allen in 1975.

Much of this effort would require “negative emissions,” or pulling carbon dioxide from the atmosphere, not merely reducing its emissions from energy, transportation and infrastructure over its 12-country footprint. To do that, Microsoft will have to be heavily involved in protecting forests from deforestation to continue to act as a carbon sink, and contribute significantly to the reforestation of vast tracts of degraded land in order to pull more pollution from the sky.

My story focuses on the company, Pachama (Andean for Earth mother) that will do the high-tech aerial monitoring to verify that Microsoft’s carbon offset investments are intact and growing. It’s a critically important job if we are to get an accurate read on whether Microsoft, and others, are truly reducing their carbon footprint. I rarely get to write optimistic stories on climate mitigation, but this one certainly qualifies. It was a pleasure to interview the company’s smart and idealistic founder, Diego Saez-Gil.

Diego Saez-Gil, a native Argentinian with a graduate degree from Stanford, is a serial Silicon Valley entrepreneur. Pachama is his third company. He got the idea while touring the Peruvian Amazon with his two brothers and witnessing massive deforestation from illegal gold mining. “We all wanted to do something about it,” he said. Image courtesy of Pachama.