The Effect of Climate Change on Herbaceous Biomass and Implications for Global Cattle Production

Climate change may affect livestock production—particularly cattle—by changing the available herbaceous biomass (nonwoody plants such as grasses that are consumed by livestock) on rangelands. This report uses G-Range (a global, gridded rangeland model) to simulate the spatial and temporal effects of changes in temperature and rainfall as projected by a climate change scenario of high greenhouse gas concentration known as Representative Concentration Pathway 8.5. We find that, on average, global herbaceous biomass declines by 4 percent, with wide regional variation. Some regions experience increases in herbaceous biomass, particularly those with cooler climates where warmer temperatures may benefit plant growth, such as Northern Europe. Other regions may experience losses, such as West Africa, which more than offset gains elsewhere. This report also estimates how these changes may affect cattle production globally and by region. Rangeland beef and milk production could increase in some regions, particularly in North America, while falling in others, leading to negligible change on a global level for beef production and a 1-percent reduction in milk production. If herbaceous plants respond positively to higher levels of carbon dioxide in the atmosphere, losses to herbaceous biomass would be mitigated, leading to a 12-percent gain in beef production and an 11-percent gain in milk production.