Global economic models with a focus on agriculture provide a perspective on the range of potential changes in market outcomes because of climate change. In one study comparing several SSPs to a future with no climate change to one with impacts from RCP8.5, 2050 yields with climate changes impacts are 17% smaller on average than those without climate change. Adaptation by farmers reduce that to an 11% decline. The change in 2050 prices of all crops and regions after climate change impacts and farm-level adaptation is a mean 20% increase . Substantial differences arise from both the heterogeneous impacts of climate change over crops and geography and the diversity of modelling approaches in the GCM and crop models. A later study with more socioeconomic scenarios and fewer models got roughly similar results , as did a modelling study focused on food security in South Asian countries .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report