Interesting link, Huan, and it got me thinking about something which happens here, locally. Yuma produces, against all odds, tons of vegetables and fruits, and is the lettuce capital of the United States, if not the world. However, not one single produce item is sold locally, except by private farmers. Private farmers only make up roughly 5%, if even that, of the total agricultural economy. Everything else is grown here, then shipped elsewhere for distribution and selling. End result? Higher prices for produce items, shortages, and non availability, even though I might see a fully loaded produce truck rolling towards California with the same item grown locally not in the local stores.
What got me thinking all that was the section in that article about irrigation projects which could benefit sub-Sahara Africa, but which currently aren't in place. The only reason Yuma can produce anything except sand is due to the extensive irrigation and canal network, started in the Teens and basically finished during the early 50's.
There is enough food to feed everyone. Just gotta stop paying farmers not to grow something, and urge them to diversify their crops. Add to that education on crop rotation to oversea farmers and a better global distribution network and there should be enough for all, with extra for storage. Howsoever, that raises another question. Historically, when people are fed, they make babies. Lots of babies. Even if conditions have improved to the point of low infant mortality/morbidity. It took a couple of generations for most Americans to get to grips with that, but there are those who just don't care. A relation of mine has 9 or so children, I think. It's been awhile since I last saw them. At that time, they had 6 and were planning more.