Climate change and food security: risks and responses

I. RISKS: CLIMATE CHANGE IMPACTS ON FOOD SECURITY – OVERVIEW OF 
LATEST KNOWLEDGE
The latest IPCC report confirms the main findings of previous IPCC reports on the evolution of 
the climate as well as its main physical effects, such as consequences for land and ocean temperature 
change, sea level rise and ocean acidification. It also brings better understanding of potential 
spatial changes in precipitation, in intensity and seasonal distribution. Moreover, improvements 
in modelling as well as in data collection and use enable us to improve the projections of climate 
change impacts in the medium term and at local scales. These improvements are of crucial 
importance to better understand and project potential impacts on agricultural systems.
Climate change generates considerable uncertainty about future water availability in many 
regions. It will affect precipitation, runoff and snow/ice melt, with effects on hydrological 
systems, water quality and water temperature, as well as on groundwater recharge. In 
many regions of the world, increased water scarcity under climate change will present a 
major challenge for climate adaptation. Sea-level rise will affect the salinity of surface and 
groundwater in coastal areas.
Climate change is likely to affect the frequency and intensity of extreme events. The 
magnitude of impacts of extreme events on agriculture is already high. FAO's recent analysis 
of 78 post-disaster needs assessments in 48 developing countries spanning the 2003–2013 
period shows that 25 percent of all economic losses and damages inflicted by medium- and 
large-scale climate hazards such as droughts, floods and storms in developing countries affect 
the agriculture sectors.
Climate change is profoundly modifying the conditions under which agricultural 
activities are conducted
Climate change has both direct and indirect impacts on agricultural production systems. Direct 
impacts include effects caused by a modification of physical characteristics such as temperature 

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levels and rainfall distribution on specific agricultural production systems. Indirect effects are 
those that affect production through changes on other species such as pollinators, pests, disease 
vectors and invasive species. These indirect effects can play a major role. They are much more 
difficult to assess and project given the high number of interacting parameters and links, many 
of which are still unknown.