Fifteen years from now food shortages, triggered by the combination of climate change and population explosion, will impact significantly on even advanced western societies. Crops will fail widely, on a regular basis. The cost of food will be relatively a lot more than it is now, and the availability of it a lot less dependable.
You mean the same crop shortages that were going to faminize the 1980's...or the 1990's...or...
There is little chance of that happening in the US, come live out here in the corn belt and even with the OMG, IT'S THE DUST BOWL ALL OVAR AGAIN!!!! and you will see that farmers will grow crops that are drought AND reasonably flood resistant (and with easy to install drainage tile...the latter is moot anyway!).
People also tend to forget that countries like India and China use manual farming techniques since there is a LARGE amount of unskilled labor there who is willing to do the work cheaper than a gallon of petrol. Once wages rise faster than the cost of a gallon of gas....then you will see modernization of those agri-businesses and yields will substantially climb.
A mathematician is a device for turning coffee into theorems. -- P. Erdos