The mean temperature of France and northern Italy rose by 3.6°C in 2003. This doesn’t sound like much, but this slight increase in temperature killed 30 000 people. And this is to become the norm.
A report in Science magazine shows that the average seasonal temperature in the tropics and sub-tropics at the end of the 21st century will be higher than any recorded between 1900 and 2006. The scientists say that it is very likely that “the warmest summers during the past century will represent the norm by the end of the century”.
This is not just worrying in terms of human casualties from “heat-related causes”, but also in terms of agriculture and the very likely possibility of a global food crisis.
The extreme heat of 2003 severely affected many European countries’ ability to produce food on the scale that they had before. The record high temperatures during the growing season “reduced leaf and grain-filling development of key crops such as maize, fruit trees and vineyards”. The crops matured ten to twenty days earlier than normal. The temperatures also dried out the soil.
Another example is the USSR in 1973. They also faced a temperature spike, which caused a 13% reduction in grain production.
The affect this rising temperature has on the international markets and food prices is not to be underestimated. Scientists warn that “heat stress on crops” will occur in a world with rapidly increasing food requirements, and is thus more sensitive to swings in market prices. “High and variable prices are most damaging to poor households that spend the majority of their incomes on staple foods,” says the article.
However, the report suggests that if we plan properly, the higher global mean and proportionally decreasing crops do not necessarily ring our death knell. Governments need to act and make plans, such as developing plants that are more resistant to heat.