Will global warming make the world’s food insecurity worse? Agriculture depends on the climate and it is going to change over the next few years. However, it is hard to get an overall picture because situations are so varied.
A slight temperature increase (between 1 and 2°C) will improve productivity at high and middling attitudes. In Europe, yields could increase by 30%. The northern boundary of farming activity will move up by a few hundred kilometres northwards. However, there will be more droughts and floods that will threaten crops, and even create food crises.
A higher temperature increase (between +2 and +3°C) means the negative effects will have greater impact. The loss of arable land through desertification will get worse and neutralise positive effects felt elsewhere on the Earth.
From +3 °C, the major secondary effects will become apparent. Water needed for irrigation will increase by 5 to 20% depending on the place. Developing countries – often located at lower latitudes, especially in Africa, will have to import more food. The price of agricultural products will increase proportionally. In total, between 40 and 170 million more people will suffer from hunger, mainly in Africa. In parallel, the increase in CO2 concentration which will certainly exceed 500 ppm will have a positive effect: it will activate photosynthesis and therefore increase agricultural production. But the overall result will be negative.
As always, the weakest populations will suffer the most. But, at any rate, the extent of the changes will depend on Man’s reaction. Agricultural politics, changing farming practices and socio-economic development will have more effect than global warming itself.