Sasankh Munukutla, BS ’22, MS ’23: Harnessing Earth’s Natural CO2 Removal Process

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Sasankh Munukutla is aiming for gigaton-scale carbon removal through enhanced rock weathering. | Sasankh Munukutla

As a student at Stanford, Sasankh Munukutla spent much of his time exploring how technologies such as artificial intelligence and computer vision could address major global problems, especially climate change. This, along with his love for global food cultures and understanding of the challenges facing farmers having grown up in the global south and the tropics, led him to start Terradot, a start-up that is fighting climate change while boosting farming productivity.

“When I zoomed out, I realized everything was a climate problem in one way or another,” Munukutla says.

The journey that brought him to Terradot began with soil. After learning about the potential of the world’s soils to capture and storecarbon, he and co-founder James Kanoff decided to focus on carbon removal by conducting research with Scott Fendorf, professor and head of the Soil and Environmental Biogeochemistry Lab at Stanford, who assisted with the inaugural Hacking for Climate Change and Sustainability class in the winter of 2022. With an Innovation Transfer Grant from the TomKat Center for Sustainable Energy, a Scientific Advisory Board and team of leading experts led by Fendorf, they ran a pilot on more than 250 hectares of farmland and raised venture capital funding to rapidly accelerate progress.

Today, the team focuses on a solution called enhanced rock weathering (ERW), which they see as the most scalable and impactful way of permanently capturing carbon from the atmosphere. The earth has a natural carbon removal process called the silicate weathering cycle. In this process, carbon dioxide from the atmosphere dissolves in rain and ground-water and weathers silicate rocks, releasing cations and converting the dissolved carbon dioxide into bicarbonate and carbonate anions, most of which are transported to the ocean and locked away for hundreds of thousands of years.

ERW reduces the time this takes from millennia to years by crushing the rocks to increase their surface area and applying them to large areas of land, including agricultural land. This helps farmers by serving as a potential substitute for lime, which fights soil acidity and improves soil quality, increasing productivity and yields.

Another advantage of ERW, explains Munukutla, is that billions of tons of silicate rocks are available in the form of byproducts produced in the mining and construction sectors. “It’s a land-based solution, with important co-benefits for farmers and food security,” he says. “It has the potential to remove billions of tons of carbon a year.”

Critically, this solution met the team’s goal: to use technology to fight climate change while restoring the world’s degraded land and improving farmer livelihoods. Terradot’s website says it all. Rather than a carbon removal company, it describes itself as “The Earth Regeneration Company.” And to enshrine its impact mission in its articles of incorporation, the team founded Terradot as a public benefit corporation.

For Munukutla, this connects his commitment to tackling social inequities with the urgent need to address climate change. “I was searching for something like Terradot,” he says. “The way it came to me was very natural, and it fully aligned with my values and the kind of impact I want to have in the world.”

The Problem

According to the Intergovernmental Panel on Climate Change, preventing global temperatures from rising due to climate change will require the removal of carbon dioxide at a massive gigaton scale. At the same time, 90% of the world’s soil could be severely degraded by 2050, something that, through loss of food, ecosystem services, and income, could cost the global economy up to $23 trillion, according to the UN’s Food and Agriculture Organization.

In combining climate action with soil regeneration, Terradot is addressing what Munukutla sees as a looming global crisis — a growing population caught in a vicious cycle of climate change, food insecurity, and human suffering.

ERW can play a vital role in addressing this but scientists have identified high-quality measurement, reporting, and verification (MRV) as critical in enabling EWR to gain the trust needed to attract the climate finance required to scale.

“There’s a lot of interest and excitement in ERW, but the key to unlocking it as a global climate solution is high-quality MRV,” says Munukutla. He explains that despite the simplicity of the solution — applying crushed rock powder to fields — measuring and verifying how much carbon it captures at scale is difficult. “You have to track the carbon through the soil, into the groundwater, then streams, rivers, and ultimately the ocean, where it is stored for hundreds of thousands of years. Nothing about that is easy.”

The Solution

For Munukutla, what will underpin the success of Terradot is high-integrity science-backed MRV. To advance the scientific foundation of ERW, Terradot is building irrefutable ground-truth MRV that uses multi-phase, multi-period samples across soil, water, gas, and plants to measure removal empirically, going beyond the current leading methodologies and standards.

At the same time, Terradot is using data from its deployments and trials to build a fully integrated biogeochemical and reactive transport model (scientific-process based models) to quantify all the impacts of ERW, especially carbon dioxide removal and crop performance. This will enable MRV to be deployed accurately at scale in the future.

In an approach similar to a research lab, Terradot is highly collaborative in the way it develops its science and technology and is planning to publish its work and bring together leading experts from around the world. “Climate action scales at the speed of trust. Transparency is critical for this,” says Munukutla.

Meanwhile, to maximize impact, the team is starting its work in regions that will be disproportionately impacted by climate change and where most potential exists for carbon removal due to favorable conditions, such as warm, wet tropical climates and slightly acidic soils that provide optimal conditions for weathering. “Brazil is one of the best places in terms of those conditions and has massive potential for community impact through carbon dioxide removal and soil health improvement,” says Munukutla. “And it has large-scale mining and agriculture infrastructure, which makes it possible to scale impact rapidly.

Use of ERW in agriculture has many advantages, Munukutla says. It can increase soil nutrients, neutralize soil acidity, and improve crop resilience to droughts and disease. Healthier soil can also increase crop yields, improving farmer incomes.

As Terradot grows — and the target is a billion metric (gigaton) tons of removals a year by 2030, in line with planetary goals — Munukutla anticipates that the cost of removals will fall, specifically by improving MRV science and technology and deploying ERW in large-scale supply chains.

“Because we’re quantifying it scientifically, that will build confidence in the system,” he says. “So this can attract climate finance first and then other industries with existing large-scale supply chains will see its value.”

The Innovator

Munukutla, who is from Singapore, was exposed from a young age to global challenges such as food insecurity and the struggles of farmers. He spent much of his youth in the global south and tropical Asian countries, including India, where he experienced the impacts of climate change directly, from increased flooding to forest fires. He saw the challenges of poverty and recognized the need for inclusive sustainable development.

This instilled in him a strong moral sense of responsibility and a desire to work for social impact. Before enrolling at Stanford, two gap years he took to serve in the Singapore military as a commander which reinforced his service mindset.

Long before the birth of Terradot, Munukutla found ways of using technology to create social impact. On a Stanford CS+Social Good Summer Fellowship, for example, he built technology to help non-profit Tarjimly scale its language translation services in refugee camps globally and provide hundreds of hours of free on-demand translation in detention centers in the United States. During several years leading the CS+Social Good on campus, he worked to scale up the technology for social impact ecosystem at Stanford and beyond.

Also at Stanford, as part of the Stanford Machine Learning Group, he published research under pioneering computer scientist Andrew Ng on using AI, remote sensing, satellite imagery, and computer vision to identify sources of methane emissions globally.

Munukutla highlights the importance of global cooperation and multilateral trust in scaling climate action. Deeply passionate about international climate policy, in 2023 in Dubai he represented Singapore as a Climate Youth Delegate focusing on Article 6 Negotiations as part of the Singapore Delegation at the UNFCCC’s Conference of Parties.

Such experiences have increased his understanding of the inextricable links between climate health and communities’ health. They have also led him to find a way to remove large amounts of carbon from the atmosphere while contributing to farmer livelihoods and global food security.

“We have the best of both worlds,” says Munukutla of Terradot. “We’re doing the best science on carbon removal but also on crop productivity and soil health — and that combination allows us the opportunity to have holistic impact.”