Climate change and food security: risks and responses

Climate change affects livestock production in multiple ways
, both directly and 
indirectly. The most important impacts are experienced in animal productivity and health 
as well as, yields of forages and feed crops. In various countries in sub-Saharan Africa, 20 to 
60 percent losses in animal numbers were recorded during serious drought events in the past 
decades. In South Africa, dairy yields may decrease by 10 to 25 percent because of climate 
change. Increased temperatures and reduced precipitation can cause important drops in forage 
production, such as the 60 percent deficit of green fodder during the 2003 summer in France. 
Climate change and climate variability are impacting forests
and their capacity to deliver 
the wide range of goods and environmental services on which an estimated 1.6 billion people 
fully or partly depend for their livelihoods and resilience. Evidence shows that in various regions 
climate change is contributing to decreased productivity and dieback of trees from drought 
and temperature stress, increased wind and water erosion, increased storm damage, increased 
frequency of forest fires, pest and disease outbreaks, landslides and avalanches, changes in 

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CLIMATE CHANGE AND FOOD SECURITY: RISKS AND RESPONSES
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ranges of forest plants and animals, inundation and flood damage, saltwater intrusion and sea-
level rise, and damage from coastal storms. This can jeopardize the contribution of forests to 
the resilience of agricultural systems, such as for instance the water and temperature regulation 
at landscape level and the provision of habitats for important species like pollinators.
Climate change affects capture fisheries and the development of aquaculture
in marine 
and freshwater environments. Impacts occur as a result of both gradual atmospheric warming 
and associated physical (sea and inland water surface temperature, ocean circulation, waves and 
storm systems) and chemical changes (salinity content, oxygen concentration and acidification) 
of the aquatic environment. Increased occurrence of coral reef bleaching has been observed, 
threatening habitats of one out of four marine species. Various fish species are already migrating 
poleward, resulting in the rapid “tropicalization” of mid- and high-latitude systems. A large-
scale redistribution of global marine fish catch potential is forecast, with a decrease of up to 
40 percent in the tropics, and an increase of 30 to 70 percent in high-latitude regions. In the 
Mediterranean, it has been observed that invasive species from lower-latitude regions have 
arrived in recent years at the rate of one new introduction every four weeks. Abundance and 
species diversity of riverine fish are particularly sensitive to disturbances in the quantity and 
timing of water flows, and especially to lower water levels during dry seasons. Pressures on river 
flows may be exacerbated by human action to retain water in reservoirs and irrigation channels.