The Environmental Food Crisis

Global climate change may impact food production across a range of pathways (Figure 17): 1) By changing overall growing conditions (general rainfall distribution, temperature regime and carbon); 2) By inducing more extreme weather such as floods, drought and storms; and 3) By increasing extent, type and frequency of infestations, including that of invasive alien species (dealt with in a separate section). IMPACTS OF CLIMATE CHANGE ON YIELD

The estimated impacts of changes in the general climate re- gime vary with the different models in the short to mid-term (2030–2050), but after 2050 an increasing number of models agree on rising negative impacts (IPCC, 2007; Schmidhuber and Tubiello, 2007). Many models have projected that the po- tential for global food production may rise with increases in local average temperature over a range of 1–3ºC (before 2050),

Projected impacts of climate change

Global temperature increase (relative to pre-industrial)

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Food

Falling crop yields in many areas, particulary developing regions

Possible rising yields in some high latitude regions

Falling yields in many developed regions

Water

Small mountain glaciers disappear, impacts on water supplies

Significant decreases in water availability in many areas, including Mediterranean and Southern Africa

Sea level rise threatens major cities

Ecosystems

Extensive damage to coral reefs

Rising number of species face extinction

Extreme weather events

Rising intensity of storms, forest fires, droughts, flooding and heat waves

Risk of abrupt and major irreversible changes

Increasing risk of dangerous feedbacks and abrupt, large-scale shifts in the climate system

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Figure 17: Projected impacts of climate change. (Source: Stern Review, 2008).

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