Scientists Create the World's Most Detailed Rice Map

A team of scientists has built the most detailed map of rice farms ever made. The map is called RiceExtent v1.0 and it covers the entire world. Researchers used satellite images and data from dozens of countries to create it. The goal is to help people make better decisions about food, water, and farming — especially as the climate changes.

Rice is one of the most important foods on Earth. More than half of all people eat it every single day. Because rice farming uses a lot of water and land, knowing exactly where it grows is very important. Scientists, governments, and aid groups all need accurate maps to plan for droughts, floods, and food shortages.

Before this map existed, scientists had to rely on general land cover maps. These older maps grouped all crops together and could not tell rice apart from wheat or corn. Many of them also lacked detail, so they missed small rice fields. This was a big problem in countries like Bangladesh and Nigeria, where farms are often tiny and spread out.

To fix this, researchers gathered dozens of rice maps made by countries around the world. They also used a high-resolution satellite map from the European Space Agency called WorldCover. This map can show details as small as 10 meters on the ground — about the length of a school bus. The team combined all of these sources into one unified global map.

The scientists used a careful, step-by-step method to decide which data to trust most. Maps made by local governments or research groups were given the highest trust, because local experts know their land best. Satellite maps that covered a full growing season were trusted more than those showing only a single moment. This helped make the final product as accurate as possible.

The final map covers 72 countries and shows about 1.67 million square kilometers of rice farmland. That area is roughly the size of Iran, or about twice the size of Texas. The numbers matched closely with estimates from the United Nations Food and Agriculture Organization. That organization had previously reported about 1.65 million square kilometers of rice worldwide.

Asia grows by far the most rice in the world. The RiceExtent map found that about 90 percent of all rice is grown there. India and China together account for more than half of all the rice area on the entire map. Other important rice regions include West Africa, the southern United States, and parts of South America.

Researchers tested the map using more than 40,000 real-world data points from four continents. In Asia, the map correctly identified rice fields between 89 and 92 percent of the time. In Africa, the accuracy rate was about 87 percent. South America scored 79 percent, partly because fewer local maps were available for that region.

The map does have some limits. It tends to show more rice area than official government records in places like Thailand and China. The scientists say this happens because the map captures the maximum possible rice extent — including fields farmed only occasionally. In other places like Bangladesh, the map actually shows less rice than expected because local data was scarce.

RiceExtent v1.0 is available for free download from an online repository. Scientists everywhere are invited to share their own local rice maps to improve future versions. The dataset also includes maps for other major crops such as wheat, corn, and soybeans. This makes it a powerful tool for studying farming, water use, and the effects of climate change around the world.