Climate Change Threatens Global Grazing Systems; Up to 50% Grazing Land May Become Unviable by 2100

A new scientific study has warned that climate change could dramatically shrink the world’s grazing landscapes, with 36–50 percent of currently viable grazing land projected to become unsuitable by 2100, posing serious risks to global food systems and rural livelihoods.

The research, conducted by scientists at the Potsdam Institute for Climate Impact Research (PIK) and published in the journal Proceedings of the National Academy of Sciences (PNAS), highlights the growing vulnerability of grassland-based livestock systems to rising global temperatures.

World’s Largest Production System at Risk

Grassland grazing systems currently cover around one-third of the Earth’s land surface, making them the largest agricultural production system globally. These systems support pastoral communities and livestock that are essential for food security, employment, and cultural traditions across many regions.

According to the study, climate change will significantly alter the environmental conditions required for grazing. Scientists assessed grazing suitability using a “safe climatic space” framework that considers four key environmental factors:

• Temperature
• Rainfall
• Humidity
• Wind speed

Historically, grazing systems have thrived within temperature ranges of −3°C to 29°C, annual rainfall between 50 and 2,627 mm, humidity levels of 39–67 percent, and wind speeds of 1–6 metres per second.

However, global warming is expected to push many regions beyond these thresholds.

Millions of Livelihoods Under Threat

The study estimates that shrinking grazing suitability could affect:

• 110–140 million pastoralists worldwide
• 1.4–1.6 billion grazing animals, including cattle, sheep, and goats

Alarmingly, 51–81 percent of affected populations live in low-income countries already facing hunger, political instability, gender inequality, and economic vulnerability.

Lead author Chaohui Li, formerly a researcher at PIK and now with the Barcelona Supercomputing Center, noted that climate change will sharply reduce the geographic areas where livestock grazing can sustainably occur.

“Climate change will shift and significantly contract these spaces globally, leaving fewer areas for animals to graze,” Li said, adding that the greatest impacts will occur in already fragile regions.

Co-author Maximilian Kotz emphasized that grazing systems are deeply dependent on environmental stability, warning that centuries-old farming practices could face unprecedented disruption.

Africa Identified as Major Hotspot

Researchers identified Africa as the most vulnerable region. Depending on future emissions pathways:

• African grazing land could shrink by 16 percent under low-emission scenarios
• Losses could reach up to 65 percent if fossil-fuel use continues to expand.

Key grazing regions — including the Ethiopian Highlands, East African Rift Valley, Kalahari Basin, and Congo Basin — are expected to experience southward climate shifts.

Because Africa’s southern boundary ends at the Southern Ocean, suitable climatic zones may effectively move beyond the continent, resulting in permanent loss of grazing land.

Prajal Pradhan of the University of Groningen and PIK explained that traditional adaptation strategies such as herd migration or switching livestock species may no longer be sufficient.

“The changes are simply too large. Moving herds or changing species will not fully compensate for the loss of safe climatic space,” he said.

A Fundamental Challenge to Food Systems

The findings underscore a growing concern among scientists that climate change is not only altering crop production but also threatening livestock systems that sustain millions of people worldwide.

As grazing areas shrink and shift geographically, policymakers may need to rethink land management, livestock systems, and climate adaptation strategies to safeguard food security and pastoral economies in the decades ahead.

The writer of this article is Dr. Seema Javed, an environmentalist & a communications professional in the field of climate and energy