image: A recent Nature study shows a subset of crops likely to be affected by climate change, accounting for realistic adaptation. The data from that paper are now publicly available.
Credit: Climate Impact Lab
A new dataset released via the Human Climate Horizons (HCH) data platform by the United Nations Development Programme (UNDP) Human Development Report Office, in collaboration with the Climate Impact Lab, warns that climate change is set to dramatically undermine agricultural productivity, with some of the greatest risks concentrated in countries least able to adapt.
The dataset, sourced from a Nature study released in June by the Climate Impact Lab and collaborating institutions [press release], finds every additional degree Celsius of global warming on average will drag down the world’s ability to produce food by 120 calories per person per day, or 4.4 percent of current daily consumption.
“If the climate warms by 3 degrees, that’s basically like everyone on the planet giving up breakfast,” said Solomon Hsiang, professor of environmental social sciences at the Stanford Doerr School of Sustainability and one of the senior authors of the Climate Impact Lab study.
That’s a high cost for a world where more than 800 million people at times go a day or more without food because of inadequate access.
“Climate change is not just an environmental challenge—it is a profound development crisis,” said Pedro Conceição, Director of UNDP’s Human Development Report Office. “High agricultural yields are important not just for food security, they also sustain livelihoods and open pathways for economic diversification and prosperity. Threats to agricultural yields are threats to human development today and in the future.”
Ahead of COP30 in Brazil, the data also shows that reducing emissions matters. If emissions were to rapidly plummet to net zero, global crop yields would decline by 11 percent. But, if emissions were to continue to rise unchecked, global yields would decline by 24 percent. This holds true across wealthy and poor countries alike.
Robust data and global coverage
The new projections link climate variables to agricultural yields for six staple crops—corn, rice, wheat, soy, cassava, and sorghum—spanning the globe. The source projections examined how farmers are likely to adapt under two different climate scenarios: one where emissions are moderate and one where they remain high. The HCH analysis focuses on human development implications and examines three time periods: the near term (2020-2039), mid-century (2040-2059), and the end of the century (2080-2099), providing data for more than 19,000 subnational regions in over 100 countries. Together, these data provide a high-resolution, evidence-based view of how rising temperatures and emissions trajectories could reshape global food systems and human development outcomes.
Globally, outside of rice yields, the odds that yields will decline by century’s end range from roughly 70 percent to 90 percent for each of the other staple crops. And taking actions to adapt—like switching crop varieties, shifting planting and harvesting dates, or altering fertilizer use—doesn’t eliminate the threat. The data shows these adjustments offset about one-third of climate-related losses in 2100 if emissions continue to rise, but the rest remain.
Countries hit the hardest
The data show that the world’s poorest countries face some of the steepest losses in agricultural productivity, with median national crop yields projected to decline by around 25-30 percent by the end of the century if emissions remain high. Sub-Saharan Africa and parts of Asia are especially vulnerable, due to the high loss of cassava crops that are vital to the world’s poor.
Meanwhile, “breadbasket” economies like the United States and other major wheat and soy producers are not insulated. Under severe warming, they show the largest yield losses, with declines in these regions reaching 40 percent, with potential ripple effects on food prices, trade, and global stability.
“Places in the Midwest that are really well suited for present day corn and soybean production just get hammered under a high warming future,” said lead study author Andrew Hultgren, an assistant professor of agricultural and consumer economics in the College of Agricultural, Consumer and Environmental Sciences at the University of Illinois Urbana-Champaign. “You do start to wonder if the Corn Belt is going to be the Corn Belt in the future.”
New innovations to target resources
The Climate Impact Lab, based at the Energy Policy Institute at the University of Chicago (EPIC), is working to help governments make informed decisions about where to direct adaptation investments, recognizing that many farmers still lack access to even basic agricultural resources, such as accurate weather data.
Another University of Chicago initiative is stepping up on this front. The Human-Centered Weather Forecasts (HCF) Initiative leverages the power of artificial intelligence to evaluate and build weather forecasts that can target what citizens on the ground need to know. This summer, they worked with the Indian government to bring 38 million farmers advanced notice of the rainy season. As climate change makes weather more unpredictable, such tailored forecasting provides farmers with an essential tool for adaptation.
“Once the rain starts, it can be too late to make big important decisions, like changing a crop, planting more land, or forgoing the farming season and getting a job in the city instead. By providing an accurate forecast around a month in advance, farmers were able to align their decisions with the coming weather and make better choices,” says Harris Public Policy Assistant Professor Amir Jina, a co-director of the HCF and researcher at the Climate Impact Lab who helped produce this data. “We’re working with governments to provide citizens with actionable climate information and ensuring they have the tools to adapt and thrive in an increasingly uncertain environment.”