During my lifetime, the human population of this planet has tripled from 2.5 billion to 7+billion. It is expected to reach 10 billion by the time I leave. We are going to need a LOT more food. Will it be there?
Demand is expected to rise as much as 14 percent each decade, as the world population is projected to grow to 9.6 billion in 2050, from 7.2 billion today, according to the United Nations, and as many of those people in developing countries acquire the money to eat richer diets.
Scientists from a United Nations panel, the Intergovernmental Panel on Climate Change, conclude that rising temperatures will have some beneficial effects on crops in some places, but that globally they will make it harder for crops to thrive — perhaps reducing production over all by as much as 2 percent each decade for the rest of this century, compared with what it would be without climate change.
More information is here: http://www.nytimes.com/2013/11/02/science/earth/science-panel-warns-of-risks-to-food-supply-from-climate-change.html