Vulnerability of cattle production to climate change on U.S. rangelands
The report examined multiple climate change effects on cattle production for U.S. rangelands to estimate relative change and identify sources of vulnerability among seven regions. Climate change effects to 2100 were projected from published models for four elements: forage quantity, vegetation type trajectory, heat stress, and forage variability. Departure of projections from a baseline (2001–2010) was used to estimate vulnerability. Projections show: an increase in forage quantity in northerly regions, a move toward grassier vegetation types overall but with considerable spatial heterogeneity, a rapid increase in the number of heat-stress days across all regions, and higher forage variability for most regions. Results are robust across multiple elements for declining production in southerly and western regions. In northern and interior regions, the benefits of increased net primary productivity or more grassy vegetation are mostly tempered by increases in heat stress and forage variability. Because projected directions of change differed, use of projections for only one element will limit our ability to anticipate impacts and manage for sustained cattle production.