Estimating the impacts of climate change on California rangelands and cattle production

Authors: Ostoja, Steven; CHOE, HYEYEONG - Seoul National University; ALVAREZ, PELAYO - National Audubon Society; KERR, AMBER - University Of California Berkeley; THORNE, JAMES - University Of California, Davis; Balachowski, Jennifer; Reyes, Julian Jon

Submitted to: Journal of Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/26/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary: Climate change is expected to force significant shifts across many natural and managed landscapes of California. Rangelands, which are largely rain-fed annual grass and forb dominated will experience such cliamte induced change. We used climate models and projected plant water stress to asses which of the states counties would be most and less impacted by future climate change impacts. We link those finding to the counties that have the most land area classified as rangelands and also to the counties that have the highest beef production to evaluate impacts to both rangeland based ecosystem services, like biodiversity and the beef production industry. We do offer several approaches for land and range managers to adapt to a changing future to buffer potential effects.

Technical Abstract: California rangelands are unique socio-ecological systems that provide a broad range of ecosystem services and support a >$3 billion annual cattle ranching industry. However, climate change poses significant challenges for the future sustainability of California rangelands. We examined changes in climatic water deficit (CWD), an indicator of plant water stress, and climate exposure to evaluate potential future climate change on various rangeland vegetation types. We used two downscaled climate models (MIROC and CNRM, under RCP8.5 in 2040-2069) and known vegetation-climate relationships to predict climate change effects using metrics and spatial scales that have management relevance. We found that at least 80% of the area of each rangeland vegetation type evaluated will experience higher CWD by 2040-2069. We assess these results from the perspective of county-level beef cattle inventory to show how climate exposure may impact actual cattle production. Finally, we briefly consider the role of adaptive capacity of the rangeland plants, livestock, and human management to reduce or mitigate climatic impacts to these systems.