The throngs of protestors in the streets of Cairo this week have a host of grievances.
There are the decades of authoritarian rule of course, and the lack of political expression or economic opportunity. But the uprising grew in part out of protests against high food prices.
Food price inflation in Egypt was over 20 percent last year. In particular, there's been a big squeeze from the rising the global price of wheat.
New York global investment manager Vincent Truglia says depending on how you measure it, the price of wheat went up between 50 and 70 percent in 2010.
"This has just devastated Egyptian budgets," says Truglia, who is managing director of global economic research at Granite Springs Asset Management.
Egypt is among the world's largest importers of wheat, and the global wheat market received a number of nasty shocks recently. The worst came last summer, when Russia was hit by an unprecedented drought and heat wave that destroyed 40 percent of its wheat harvest.
Russia abruptly banned exports, and Egypt, which had just signed a big wheat deal with Russia, was left scrambling.
Subsidies and rationing
The Egyptian government has tried to keep a lid on wheat prices through subsidies and rationing. But Truglia says anxiety over food prices is the key problem facing Egypt today.
And some look further up the chain of events, and trace the problem at least in part to climate change.
"I think we are seeing some of the early effects of climate change on food security," says veteran environmental analyst Lester Brown, of the Earth Policy Institute in Washington. In particular, Brown says the heat wave that led to the collapse of Russia's wheat harvest was no ordinary weather event.
"If someone had told me that there was likely to be a heat wave in Russia in which the average temperature would be 14 degrees Fahrenheit above the norm – that's pushing the envelope. I mean four degrees would be a lot," Brown says.
Brown and many others say the Russian heat wave only one of several recent events effecting global food supply that likely were linked to climate change. And he believes that the stresses these events are putting on food supplies are contributing to unrest around the world.
"You can't prove that link," Brown says. "But you can say it is highly likely that that is the case."
Many observers dismiss this as far-fetched speculation. They say the possible impacts of climate change on political events are too remote and diffuse for anyone to credibly connect the dots.
But Brown has some surprising compatriots.
Among them is retired admiral Dennis McGinn, who contributed to an influential 2007 report for the Pentagon on the security implications of climate change.
"The adverse effects of bad weather caused by climate change act as a threat multiplier for instability in critical parts of the world," admiral McGinn says.
Like Brown, McGinn says you can rarely draw a straight line of causation between climate change and political upheaval. There are usually many underlying causes, he says, but climate change may well be one of them.
"If you have long term droughts and crop failures, and in other parts of the world too much water in the form of flooding, you have added pressure to the already existing fault lines in fragile societies with fragile governments," McGinn says. "And certainly Egypt would fall under that category."
So if that's true, where does that leave us?
McGinn says we need to start looking at ways to reduce the shocks and volatility that climate changes will bring to food supplies and other global markets.
That means new investments in things like drought-resistant crops, better water management and, new ways of managing and distributing food, he says.
None of this will end the threat of instability around the world, McGinn says. But it might help remove one thread of volatility in Egypt and beyond.
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