Impacts of climate change and mitigation strategies for the safe climatic space of global staple crops

Climate change and extremes pose a significant threat to global food security. With the potential for severe climate-associated production losses in the coming decades, there is a critical need for robust impact assessments accompanied by effective adaptation strategies. The Safe Climatic Space (SCS) offers a valuable framework for such assessments. It defines the historical bioclimatic envelope—specified by ranges of mean annual temperature and precipitation—within which the majority of global crop production has historically occurred. Previous applications of the SCS framework to estimate future geographical shifts in crop suitability are limited; they typically rely on static, baseline-period production data and thus fail to incorporate the direct effects of future climate on crop production. A further critical limitation is the general absence of proposed and quantified adaptation measures to maintain crop production within a viable climatic domain.This study addresses these research gaps by conducting a comprehensive global and continental-scale assessment of the impact of future climate change on the SCS for four staple crops: maize, rice, wheat, and soybean. We integrate climate data from a historical baseline (1987–2016) with mid-century future projections (2036–2065) from an ensemble of climate models. These are coupled with dynamically simulated future crop production data from global gridded crop models under two contrasting Shared Socioeconomic Pathways: the sustainable SSP1–2.6 (SSP126) and the fossil-fueled SSP5–8.5 (SSP585). This integrated methodology enables a precise quantification of the proportion of future simulated production that fall outside the historically defined SCS, providing a more realistic and dynamic assessment of climatic risk to crop production.Our results project that a substantial fraction of future global crop production will occur outside the historical SCS. Under SSP126, approximately 5.0% (model ensemble range: 3.0%–10.0%) of the total simulated global production for the four crops combined is located beyond SCS boundaries. This proportion increases to 7.0% (5.0%–15.0%) under SSP585, highlighting the sensitivity of food production to emission trajectories. Impacts are highly heterogeneous across crops and continents. Rice is identified as the most vulnerable crop, with 10.0% (7.0%–20.0%) of its global production exiting the SCS under SSP585. Geographically, Oceania is the most affected continent, with 10.0% (7.0%–35.0%) and 20.0% (14.0%–38.0%) of its total production displaced under SSP126 and SSP585, respectively, followed by Africa and Asia. Europe and North America are projected to be the least affected.Moving beyond impact quantification, this study proposes and evaluates a novel adaptation strategy: enhancing crop climatic adaptability to effectively redefine and expand the SCS. We simulate this strategy by calculating the requisite adjustments in crop-specific tolerance ranges for temperature and precipitation that would be necessary to re-incorporate projected outlying production into an expanded SCS. Our analysis indicates that to counteract projected global warming, crops would need to develop adaptive capacity for a temperature increase of approximately 1°C under SSP126 and over 2°C under SSP585. Required precipitation adaptations are more complex, exhibiting significant regional variation with no clear correlation to emission intensity. Crucially, we demonstrate that through such targeted, continent-specific adaptations, the proportion of global crop production remaining within a viable SCS could be increased to 97.0% under both future scenarios. This finding underscores the significant potential of breeding climate-resilient crop varieties as a key strategy to safeguard global food production.In conclusion, this research elucidates the patterns of future climate change impacts on the SCS for global staple crop production and introduces a proactive mitigation framework centered on crop adaptation. The findings, which reveal stark inter-continental and inter-crop disparities, provide critical insights to guide regional adaptation policies and prioritize breeding programs for enhanced climate resilience, thereby offering a viable pathway to bolster global food security under anthropogenic climate change.