Google announced on Wednesday, September 16, the largest carbon-removal purchase in the company’s history. Its partnership with climate company Terradot is expected to operate across more than 200,000 hectares of rice fields in Rio Grande do Sul, combining two strategies: rapidly cutting methane emissions from rice cultivation and removing carbon dioxide from the atmosphere with crushed volcanic rock.
The agreement stands out not only for its scale but also for its design. Rather than treating methane and CO₂ as separate problems, the project seeks to coordinate a faster-acting measure with a long-term one across the same farmland. The financial value of the transaction was not disclosed.
How the project plans to cut methane
Irrigated rice fields remain flooded during part of the growing cycle. Under low-oxygen conditions, the decomposition of organic matter in the soil encourages methane formation, producing a greenhouse gas with a powerful warming effect in the short term.
The project’s first component will introduce a practice known as Alternate Wetting and Drying. Instead of keeping paddies continuously flooded, farmers periodically drain the fields. According to Google and Terradot, the change can reduce methane emissions and water use without taking the land out of agricultural production.
The contracted target for this phase is to deliver, by 2030, an impact equivalent to the elimination of 1 million metric tons of CO₂ equivalent, calculated using methane’s global-warming potential over a 20-year period.
Crushed rock to remove CO₂ from the air
The second component uses enhanced rock weathering. Volcanic rock rich in silicate minerals is crushed and spread over the soil. As rainwater dissolves the rock, its minerals react with CO₂ and help transform it into stable chemical forms such as bicarbonates.
This process occurs naturally, but crushing the rock increases its reactive surface area and speeds up the reactions. The project aims to durably remove 1 million metric tons of CO₂ by 2040.
The agreement’s two figures represent different climate effects: the 2030 target refers to reducing methane’s warming impact, expressed as CO₂ equivalent, while the 2040 target refers to physically removing carbon dioxide from the atmosphere. Adding them together as though both represented the same type of carbon removal would be inaccurate.
Why Rio Grande do Sul
The state accounts for a large share of Brazil’s irrigated rice production and combines extensive farmland, water availability and proximity to basalt rock sources. These conditions can reduce transport distances and support the expansion of enhanced rock weathering.
According to Google, the model could eventually expand across the roughly 1.5 million hectares used for rice cultivation in Brazil and later be adapted for other major rice-producing regions. Reuters reports that Terradot began pilot activities in 2026 and plans to move toward commercial scale starting in 2028.
AI, data centers and pressure for climate results
The announcement comes as technology companies face growing scrutiny over the energy consumption and emissions associated with expanding data centers and artificial-intelligence systems. Folha reported that Google’s emissions reached 14.4 million metric tons of CO₂ equivalent in 2025, up 18% in one year and 80% from 2019.
In this context, financing carbon removal can help develop climate technologies that remain expensive. It does not, however, replace direct emissions cuts across operations, electricity use and supply chains. The Brazilian project’s actual results will depend on implementation at farms, farmer participation, and independent measurement and verification.
What the project could mean for Brazil
If it meets its announced targets, the initiative could place Brazilian agriculture at the center of a model that combines water management, methane reduction and mineral carbon removal. It could also generate data on costs, productivity, soil health and carbon permanence at a scale that has rarely been tested.
The main challenge will be turning long-term targets into measurable outcomes. The contract’s size creates expectations, but credibility will depend on transparent methods, credit verification and regular disclosure of performance.
Sources
- Google — Terradot agreement and climate targets in Brazil
- Reuters — Google’s largest carbon-removal deal
- Folha — project begins in Rio Grande do Sul
Featured image: rice harvest near Rio do Sul, Santa Catarina, southern Brazil. Illustrative image. Photo: Herr stahlhoefer/Wikimedia Commons, public domain.
