April 12, 2013
Whatever governments may or may not agree on GHG emissions, the one thing that is likely is that average global temperatures will continue to rise. What is also likely is that the world’s food production capacity will be affected by the change that temperature rises will create. There is however no consensus on what the overall effect is likely to be by the mid 21st centre or later. What is certain is that climate change which not only creates more floods, heat waves, droughts and freeze-ups will create fluctuations in agricultural production. Whatever happens, climate change is a threat to global food security – unless steps are taken to mitigate likely impacts.
As a recent report from the US Department of Agriculture puts it: “New research and development in new crop varieties that are more resistant to drought, disease, and heat stress will increase the resilience of agronomic systems to climate change and will enable exploitation of opportunities that may arise.” On this point there is scientific consensus.
Where there is wider disagreement however is how far climate change will affect crop and livestock production and which regions of the world will be the most seriously affected . There is also disagreement on how far the generally damaging effect of temperature rises will be compensated by the fertilising effect of increased atmospheric carbon dioxide. The main expected – even already apparent – effects resulting from increased CO2 and ozone levels are seasonal changes in rainfall and temperature, as well as modified pest, weed, and disease populations. The main longer term manifestations of this change in agro-climatic conditions are likely to be alteration of the length of growing seasons, and the necessary change in timing of planting and harvesting. Climate change is also likely to affect water availability and water usage rates.
Assessments of climate change effects would suggest that the implications for the most vulnerable areas of the world are both more immediate as well as the most serious. Without crop growing adjustments and mitigation action, indigenous supplies of the most important food staples will be seriously affected by the late 2030s and will have reached crisis levels by the mid-century. Without radical improvements in crop varieties, in husbandry techniques, water conservation and infrastructure improvement, the food import dependence of these regions is going substantially to increase. Even without global warming impacts, the pressure of population rise will place food supplies under greater strain than already exists. Without increased inputs into agricultural; research, education and infrastructure, this situation cannot do anything but worsen.<12/04/2013>