Floods in Pakistan, droughts in Russia, rising grain prices. According to award-winning Australian science writer Julian Cribb, these are warning signs of an impending disaster that will dwarf the financial crisis.

In his new book The Coming Famine: The Global Food Crisis and What We Can Do To Avoid It, he warns that looming scarcities of water, land, nutrients, oil and fish will leave us unable to feed ourselves within 50 years.

In this wide-ranging conversation, Mr. Cribb addresses the implications of the Western diet, the threat to cities and what impact famine could have on immigration.

Q: You must be a charming dinner companion.

A: I am a bit depressing. It's one of those issues people don't like to talk about much. But I'm a science journalist, so I've got a lot of other things to talk about besides food.

You outline a pretty scary scenario, but the idea of a looming global famine doesn't really seem to be on anyone's radar. Why is that?

Because we've been so very successful in food production over the last 30 years, that we've basically fallen asleep at the wheel. Countries like Canada, America, Australia, are awash with food. We throw half of it away. But what we really haven't noticed is the rate at which the basic resources for producing it are running out.

You say we've got less than 50 years until global crisis.

We're probably heading into, in 30 or 40 years, fairly savage disasters on a much larger scale than the Pakistan flood and the Russian droughts, which will displace large numbers of people. And the cost of that will fall on everybody.

Is that what it's going to take for people to notice there's a problem?

I hate to say it, but we're very slow on the uptake. Politicians don't like to move, unless they're really shoved out of their comfort zone. They haven't seen this big picture: the shortages of land, water, energy, fertilizer, fish, technology. I don't know what it's like in Canada, but in Australia, we haven't been investing anything in agricultural research in the last 20 years.

Are world leaders aware of the threat?

I think they're diverted by what they would regard as more immediate considerations. The financial crisis has got them all running around like ants, climate change has also been projected to them as a critical issue, and indeed it is, but it's a slower burning issue than the one that I'm flagging.

You need Al Gore to make a movie of your book.

I really do. I tried to get the publisher to send a copy to him. There has been a bit of a backlash with climate change though, and I'm hoping that won't happen with food. We live in an incredibly wasteful society and this is going to take hard work and co-operation, not just by governments and farmers and scientists, but also by individuals, in terms of the way they eat.

Is there any precedent for the world reacting en masse to a food issue?

In a sense, yes, the Green Revolution was that. In the 1960s, the Club of Rome pointed out that a lot of people in the world were starving and that was a disgrace. And the world invested a lot of money in agricultural science and shared the knowledge generously. We got super wheats and super rice. Places like India and China, which were starving, were self-sufficient in less than a decade.

But how do you convince Western countries that this will affect them? I think there's a perception that our borders will protect us.

People don't understand that famines will impinge on them personally. It will affect the prices they see, the taxes they pay, and they will get flooded with immigrants. Think of the Irish Potato Famine. A quarter of the country departed for Canada and American and Australia. A population that's starving will move.

In the 1970s, 10 million Bangladeshis went to live in India. If there's a decent famine on the North China Plain, the Chinese would simply move north into Siberia where there are only 20 million people. But the Russians might have something to say about that.

In North America, a lot of the discussion around food right now has to do with eating locally grown, organic products, and the issue of factory farming. Do you feel like this is a distraction from the larger problem?

It's exactly the kind of thing we need to do. We need to recycle and reuse and we need to eat more modestly: smaller servings and a lot more vegetables. And eating locally makes sense because you're burning less fossil fuel to get things from around the world.

One of the consequences of burning more fossil fuel is to cause more drought, which reduces growing production. So all these things are interlaced.

Is the onus on the Western world?

Yes, because our diets are the ones that are most costly in energy and water. But it's going to apply to everybody. I think it's important for advancing economies like India and China not to take the same route. If Indians start consuming meat at the same rate we do, there's essentially no way the planet can produce enough of it.

How do you change people's perception of food?

I advocate for one year of teaching food in the world's primary schools. I believe that's an ideal time to get kids, especially urban kids who are totally out of contact with their food supply. There's some research that shows some kids don't even know meat comes from animals, they think it's something you buy in plastic in the supermarket. That kind of ignorance is what will destroy us.

Have you made changes personally to your diet?

Substantially more vegetables than I used to do and less meat. It does prod your conscience.

Are there particular regions that are troubling to you?

The biggest worry would be the Indo-Gangetic plains. They have to feed 1.3 billion people, not just in India but in central China. They're very vulnerable to water scarcity and land degradation, and they're likely to get hit very hard by climate change. Things are lining up in an ominous way for that part of the world.

Another thing that really shakes me is the thought of megacities. When you have cities of 20 or 30 million that have no internal food production, they're 100-per-cent reliant on trucks coming every day. If you've got a fuel crisis or a major climatic disruption, you could have a city of that scale starving within a week or two. We're creating points of tremendous vulnerability.

Are there countries that will be harder to convince that change is necessary?

Probably Canada will be very hard to convince – because Canada grows so much food relative to its population and, of course, it's going to gain food-growing country under climate change.

Countries like Canada will be a little more complacent about these things because they do have large domestic surpluses.

But I'm talking about a global problem that will go around the world as fast as the financial crisis did.

So we'll be affected one way or another?

No one will be untouched by it. No person, no country.