Previous studies have combined climate, crop and economic models to examine the impact of climate change on agricultural production and food security, but results have varied widely due to differences in models, scenarios and input data. Recent work has examined (and narrowed) these differences through systematic model intercomparison using a high-emissions pathway to highlight the differences. This paper extends that analysis to explore a range of plausible socioeconomic scenarios and emission pathways.
Some of the most important impacts of global climate change will be felt among the populations, predominantly in developing countries, referred to as ‘‘subsistence’’ or ‘‘smallholder’’ farmers. Their vulnerability to climate change comes both from being predominantly located in the tropics, and from various socioeconomic, demographic, and policy trends limiting their capacity to adapt to change.
Climate change impacts, adaptation, and vulnerability span a vast range of topics.With the deepening of knowledge about climate change, we see connections in expanding and diverse areas, activities, and assets at risk. Early research focused on direct impacts of temperature and rainfall on humans, crops, and wild plants and animals. New evidence points to the importance of understanding not only these direct impacts but also potential indirect impacts, including impacts that can be transmitted around the world through trade, travel, and security.
This document is the result of coordinated and carefully connected cross Working Group efforts to ensure coherent and comprehensive information on various aspects related to climate change. This SYR includes a consistent evaluation and assessment of uncertainties and risks; integrated costing and economic analysis; regional aspects; changes, impacts and responses related to water and earth systems, the carbon cycle including ocean acidification, cryosphere and sea level rise; as well as treatment of mitigation and adaptation options within the framework of sustainable development.
Climate change is a significant and growing threat to food security—already affecting vulnerable populations in many developing countries, and expected to affect ever more people in more places, unless action is taken beginning today. Current scenarios for business-as-usual farming under climate change project growing food security challenges by 2050. Worst hit will be underdeveloped regions of the world where food insecurity is already a problem and populations are vulnerable to shocks (Rosegrant et al. 2014).