Paul Krugman has caused quite a stir with his claims that the riots in Egypt are the result of:
global warming > causing bad weather > causing crop failure > causing increased food prices > causing riots.
It’s rather circular logic IMHO, and one that isn’t supportable by the data at hand.
First, there is a piece, Debunking Krugman: NYT’s “Soaring Food Prices – Blame the Weather”. The author, who is open to the possibility that global warming might be problem, shows that Krugman knows not of what he speaketh. As she says, “This is so far off base, Paul Krugman, I hardly know where to start.”
Andrew Bolt has a very good piece in which he reminds us that “food production is in fact at near-historic levels and the Egyptian regime actually keeps food prices pretty stable through massive subsidies.”
So food prices probably did not trigger the problems in Egypt. In fact, because of subsidies that keep bread prices constant at low levels, many poor folk are favorably inclined toward the current regime.
Also, on Pielke, Jr’s website, Richard Tol reminds us that IPCC reports tell us that for modest global warming (of the order of 1 to 3 degrees C, I believe) , global food prices may decline. And this is despite the fact that, as shown at WUWT, negative Socioeconomic Impacts of Global Warming are Systematically Overestimated, while positive impacts are underestimated. (This is in two parts; Part II is here).
Pielke Jr. has this graph on his website to speak to the issue:
During that 70s food crisis, many of the same arguments were made that are being made today:
“We’re running out of food! People in (enter random developing country name here) will starve! There’s unrest in the third world!”
Remember this? From Wiki:
Erlich’s The Population Bomb was a best-selling book written by Paul R. Ehrlich and his wife, Anne Ehrlich (who was uncredited), in 1968. It warned of the mass starvation of humans in the 1970s and 1980s due to overpopulation, as well as other major societal upheavals, and advocated immediate action to limit population growth. Fears of a “population explosion” were widespread in the 1950s and 60s, but the book and its charismatic author brought the idea to an even wider audience.  The book has been criticized in recent decades for its alarmist tone and inaccurate predictions.
Well we all know how those predictions turned out.
Thanks to Indur Goklany, who contributed to this article.