In the Earth.org article “Grasslands Could Shrink by Half As Climate Change Intensifies, Study Warns,” author Jan Lee claims that up to 50 percent of global grazing lands could disappear by 2100 due to climate change, threatening food security and livestock systems worldwide. This is demonstrably false. Data show increased greening of the earth due to increased carbon dioxide (CO₂) in the atmosphere, and projected losses are not based on observed global grassland decline but based on speculative end-of-century climate model scenarios.
The article relies entirely on a modeling study from the Potsdam Institute for Climate Impact Research projecting a contraction of what it calls “safe climatic space” for grazing. The study defines narrow thresholds for temperature, rainfall, humidity, and wind speed and then projects that future warming will push large regions outside those bounds. That is not measurement, it is model-driven extrapolation layered onto emissions scenarios extending to 2100. No global dataset is presented showing that grasslands have begun to shrink by anything close to these figures under the roughly 1.2°C of warming experienced since the late nineteenth century.
If climate change were already driving large-scale grassland collapse, we would expect to see it in satellite and land-use data, which we do not.
As documented at Climate at a Glance Global Greening, satellite observations from NASA show a marked increase in global leaf area over the past four decades, as seen in Figure 1 below. Elevated atmospheric CO₂ has enhanced photosynthesis and improved plant water-use efficiency, particularly in semi-arid regions where many grasslands are located. The result has been measurable expansion of vegetation cover worldwide.
Rather than shrinking, many dryland and semi-arid regions have experienced increased plant growth. This CO₂ fertilization effect is not theoretical. It is observed from space and, despite its relevance, the Earth.org article does not mention it.
This greening due to increased CO₂ is something we have reported before here on Climate Realism. Data from satellite measurements indicates that the globe has increased its green area about 5 percent over the first 20 years of the twenty-first century. The Sahara Desert is becoming smaller as a result. A 2018 study found the Sahara desert had shrunk in area by 8 percent over the previous three decades, as grasses and tree cover expand into what was formerly desert.
If grasslands were collapsing due to warming temperatures, the global greening signal would not exist. Instead, satellite data show that vegetation productivity has increased across large portions of Africa, China, India, and parts of the Sahel — regions often portrayed as climate casualties. That trend is consistent with enhanced plant growth under higher CO₂ concentrations and would likely continue so long as atmospheric CO₂ remains elevated and nutrients are available.
What has reduced grassland area in many regions is not climate, but land-use change. Urbanization, infrastructure development, cropland expansion, and industrial growth convert grasslands into roads, housing, and commercial zones. That is a human land-management issue, not a climate-driven collapse. For instance, grasslands declined across the central part of the United States in the 1800s as buffalos were removed and former grasslands were converted to croplands, but that decline was not due to climate change.
The Earth.org article further frames livestock as both victim and villain, citing claims about agricultural emissions. Yet grazing systems exist precisely because large portions of the world’s terrain are unsuitable for row crops. Grasslands convert cellulose into protein through livestock, and actually improves the soil. Eliminating grazing does not transform marginal land into fertile cropland.
Most importantly, the entire projection depends on emissions scenarios stretching decades into the future. These models assume specific warming trajectories, specific precipitation responses, and specific ecosystem thresholds. They then treat those assumptions as predictive certainty. Yet, they are just assumptions and haven’t been proven in the real world. That is not observational science; it is scenario construction.
Grasslands are dynamic ecosystems influenced by rainfall variability, fire regimes, grazing management, invasive species, and land-use change. They have persisted through warmer and cooler periods throughout the Holocene, seen in Figure 2 below.
Declaring that half of all grasslands will vanish because a model projects that various regions will fall outside a defined “safe climatic space” is speculative at best. There is no empirical dataset showing a decline in global grazing suitability today, and there is some evidence historically that as climate shifts to disfavor grasslands in some areas, they become favored biomes elsewhere, resulting in a shift in areas dominated by grasslands, not necessarily a decline overall. There is no documented climate-driven global collapse of grasslands over the past 150-plus years of warming coming out of the little ice age. By contrast, there is robust satellite evidence of expanding global vegetation cover under elevated global atmospheric CO₂.
Observed data show expanding vegetation, not disappearing grasslands. Claims of a climate-driven grassland collapse is just another speculative climate disaster fairy tale presented as fact. Earth.org got their facts badly wrong by failing to examine actual data.
Anthony Watts is a senior fellow for environment and climate at The Heartland Institute. Watts has been in the weather business both in front of, and behind the camera as an on-air television meteorologist since 1978, and currently does daily radio forecasts. He has created weather graphics presentation systems for television, specialized weather instrumentation, as well as co-authored peer-reviewed papers on climate issues. He operates the most viewed website in the world on climate, the award-winning website wattsupwiththat.com.
Originally posted at ClimateREALISM
