Rice, reconsidered: How precision irrigation could help decarbonize a global staple

Rice feeds more than half the world’s population and underpins rural livelihoods across Asia, the Americas and parts of Europe. Yet despite its central role in food security, rice carries a climate footprint that is often overlooked.  

Grown largely under continuous flooding, rice accounts for an estimated 10%-12% of global methane emissions. Viewed through a climateimpact lens, emissions from flooded rice systems are often described as comparable to the global aviation industry, driven largely by methane, a shortlived but highly potent greenhouse gas. As pressure mounts to reduce “superpollutants” like methane and nitrous oxide, how rice is irrigated increasingly matters for climate outcomes. 

Corporate supply chains and public policy are engaging around how to grow rice more sustainably. Global food companies have identified rice as a priority crop, seeking to reduce emissions while safeguarding yields. Federal and state U.S. programs, particularly in major ricegrowing regions such as Arkansas, California and the Mississippi Delta, have promoted Alternate Wetting and Drying (AWD). By replacing permanent flooding with managed drydown periods, AWD has demonstrated meaningful reductions in water use and methane emissions while often sustaining yields. 

But AWD is one solution among many, and addressing climate risk in rice will require a portfolio of approaches. If a core goal is to substantially decarbonize rice production, it is worth asking whether rice must be flooded at all. 

From flood to rootzone control 

AWD still relies on flooding cycles. Microirrigation delivers water and nutrients directly to the root zone, maintaining largely aerobic soil conditions. That distinction matters for emissions. 

Across multiple field studies, microirrigated rice has shown dramatic reductions in methane (often exceeding 70% compared to flooded systems) while maintaining or even improving yields. Introducing oxygen into the soil disrupts methane formation while encouraging natural processes that consume methane before it reaches the atmosphere. Precision water application can stabilize nitrogen dynamics, reducing the risk of nitrous oxide emissions linked to excess or poorly timed fertilizer use. 

This approach is already moving beyond experimental plots. In parts of India and Southern Europe, microirrigated rice has emerged in response to water scarcity, pumping restrictions, or unreliable surface water deliveries. In the U.S., interest is growing where groundwater constraints, labor pressures, and climate commitments intersect; particularly in California’s Sacramento Valley and the Lower Mississippi Delta, where irrigation decisions increasingly carry climate implications. 

Why adoption has lagged 

Despite its promise, microirrigation remains rare in rice systems worldwide. Rice infrastructure, farmer training, and incentive programs have been built around flood irrigation for decades. Transitioning to microirrigation often requires changes in field layout, planting methods and management intensity; barriers that are especially high for smallholders globally and for riskaverse producers everywhere. In the U.S., policy signals matter: most conservation and climate programs focus on improving existing flood practices rather than supporting alternatives to flooding. 

A portfolio for rice’s future 

Rice will remain a global staple, and no single practice will fit every geography or farm. AWD represents an important and scalable improvement over continuous flooding, particularly where infrastructure or economics limit more dramatic change. But as climate targets tighten and methane comes under sharper scrutiny, rice irrigation will need a broader toolkit. From Asian smallholder plots to U.S. commercial fields, evidence increasingly suggests that how water reaches the root zone may be just as important as how much water is applied. Precision irrigation does not replace existing solutions, but it expands what is possible for one of the world’s most important crops. 

Prepared with the support of AI 

Val Fishman is advocacy and development consultant for Orbia Precision Agriculture (Netafim).