From war and disease to depleted resources and yes, even cosmic curveballs, U of T’s experts weigh in on our future: why killer asteroids are worse than killer robots, how peak oil links to nuclear war, and more.
More countries than ever have atomic bombs. Will any use them?
Anyone who grew up during the Cold War and remembers the “duck and cover” drills taught to American schoolchildren understands that global nuclear conflict was once an underlying but grimly constant concern. Since 1989, that particular doomsday scenario has receded, thanks to warmer relations between the nuclear superpowers and significant reductions in their arsenals. But the intervening years have also brought an increased risk of regional conflict among the newer nuclear states, says Janice Stein, director of the Munk School of Global Affairs. Whether you think the world is any safer today than it was 50 years ago depends on whether you consider far fewer bombs in a greater number of hands to be a good or a bad thing.
Stein sees it both ways: fewer bombs, good; more hands, not. She says her chief concern today is the ongoing tension between a nuclear-armed Israel and Iran, which appears to be pursuing its own nuclear weapons. The chances of a standoff between Pakistan and India remains, she says – although “15 years of mutual education about the dangers of a nuclear conflict there have resulted in a reduced threat.” And she sees North Korea as a wild card on a peninsula “fraught with tension.”
To reduce the risk of a nuclear detonation – either planned or inadvertent – the major world powers must do more to safeguard existing nuclear stockpiles and prevent additional countries from obtaining them, says Stein. The U.S. and Russia, especially (as well as the other long-standing nuclear states, China, the U.K. and France), have a responsibility to reduce their stockpiles. “The position that ‘the countries that don’t have nuclear weapons can’t get them, but the countries that do have them can keep them,’ is not consistent with a non-proliferation regime that can survive,” she says.
Governments must also invest in a more robust regime for controlling the global inventory of nuclear weapons and who inside each country has access to them, says Stein. She notes that this is particularly true in Pakistan, where there is an unstable relationship between the civilian government and the military and where low-level fighting among tribal groups is common. “Leakage is a real possibility,” she says.
The Iran-Israel situation needs to be defused, though Stein admits it’s difficult to see how this will happen. “If Iran is indeed on the road to nuclear weapons, we could see a pre-emptive strike by Israel – on the theory that ‘I’m going to hit you before you have the capacity to hit me back.’ That dynamic is already at work.” A nuclear Iran would heighten the risk of further proliferation within the region, she adds.
Fifty years ago, the U.S. and Russia defused the Cuban Missile Crisis with a secret agreement to deactivate certain missiles and open a Moscow-Washington “hotline.” One might ask what would happen if a similar situation arose today. The specific circumstances would be different, of course, but would our leaders –whether in Russia, the U.S., Israel or Iran – know when to step back from the precipice? – SA
We can’t prevent deadly viruses from evolving, but we’re getting better at fighting back
In 14th-century Europe, one person in three died from the bubonic plague. Between 1918 and 1919, more than 50 million people worldwide succumbed to the deadly Spanish flu. And in sub-Saharan Africa, AIDS has killed 30 million people – a toll that continues to rise. Despite extraordinary medical advances in the last 100 years, we can’t consider ourselves immune to infectious disease. “We know there’s going to be another influenza pandemic,” says Allison McGeer, a professor of laboratory medicine and pathobiology and a specialist in infectious diseases. “There has been a flu pandemic every 30 years, on average, for the last 400 years.” The question is when the next one will strike – and how severe it will be.
Any kind of virus that infects people across the globe is classified as a pandemic, even if it’s not deadly, says McGeer. However, “mortality rates make a difference to how much we worry.” SARS, for example, killed about 15 per cent of all people who contracted the virus while the 2009 swine flu killed less than one per cent. New and evolving viruses are a particular danger, such as the bat coronavirus identified in Saudi Arabia in the fall. That’s because while we can now develop vaccines within months, this is not fast enough to help anyone infected in the “first wave” of a new pandemic. If the disease is a virulent one, that delay could spell thousands – or even millions – of deaths.
Reducing the lethal impact of a pandemic requires more than medicines. “We know how slow we are to change behaviour,” says McGeer. “The pieces of the public health system have to be in place – you can’t invent them when a pandemic happens.” A world that’s prepared for the next pandemic has plenty of labs ready and watching to identify new viruses quickly and open channels of communication between scientists and the health officials who inform the public. And most importantly, people need to trust their health-care system (not always easy – in Nigeria, for example, persistent false rumours that the polio vaccine sterilizes children has made eradicating the disease there difficult).
On the medical side, “our prospects are getting better,” says McGeer, mentioning the ongoing effort to find a universal flu vaccine (half a dozen clinical trials are underway around the world). Some countries have begun stockpiling antiviral drugs, and that will help – it definitely did during the 2009 pandemic. The genetics of new viruses can now be sequenced in days if not hours and we’re making technical strides in how quickly vaccines can be developed. Though we’re still not at a stage to do much about that dreaded first wave, McGeer remains hopeful that the inevitable future pandemics will be managed well. “I don’t think there’s any question we will get better, it’s just a question how much better and how fast.” – JR
The green revolution has helped feed a ballooning global population. But industrial farming is not sustainable
How many people can the planet feed? Thomas Malthus, the English economist, predicted in the late-18th century that a growing population would eventually outstrip the Earth’s ability to support it. What he didn’t predict was the green revolution of the last century that has kept agricultural yields mostly on pace with population growth. But today, the United Nations estimates that 870 million people in the world – or about one in eight – go hungry. Are we finally reaching Malthus’s dire tipping point?
Harriet Friedmann, a professor of geography, studies food policies and how food is produced and consumed around the world. She believes there are significant flaws with the West’s industrial farming system, starting with government subsidies that make meat products artificially cheap, and which send the wrong signal to consumers and farmers. “Our entire food system has grown up around a mode of consumption that’s not sustainable for our current world population, much less a population at mid-century that may be 30 to 40 per cent larger than today’s,” she says.
Friedmann rhymes off other reasons why industrial farming is unsustainable: it uses too much water, fuel and chemical fertilizers; it devotes an increasing amount of cropland to corn and soybeans for animal feed and fuel rather than crops for human consumption; and it eliminates the small farm in favour of huge food-producing areas, which become agricultural monocultures. “It may seem that higher yields are achieved when land is converted from pasture to crops and when animals eat industrial feed,” says Friedmann. “But it makes crop farming more dependent on fossil energy used to make fertilizer – and pesticides, because monocultural fields are a banquet for pests.”
Climate change is also a concern. According to a 2008 report, the International Assessment of Agricultural Knowledge, Science and Technology for Development, higher global temperatures risk disrupting our food supply on several fronts: more frequent and severe floods and droughts; shrinking areas of habitable land and freshwater; and a higher incidence of many human, animal and plant diseases.
Friedmann says we need to refocus on land policies that preserve smaller farms, while also rethinking all of our policies around food consumption, food waste, and the renewal of soil and water – and linking them together. She suggests redirecting scientific research to collaborate with farmers, drawing on their skills. “We need to make decisions about our food system in a holistic way,” she says. There’s a lot to digest. – SA
Many of the world’s coastal cities face severe flooding – unless we stabilize our carbon emissions soon
We humans love our ocean views – so much, in fact, that 100 million of us live within a metre of sea level. This may brighten our collective mood, but the uplift could be fleeting. Dick Peltier, a University Professor of physics and an expert on global warming, notes that the UN’s Intergovernmental Panel on Climate Change has predicted that melting ice and warming oceans could raise sea levels by half a metre by the end of the century. But some scientists have suggested that, based on newer models, the rise could ultimately be more than triple that. Such a scenario would inundate many coastal cities and much of the Netherlands and southern Vietnam, and put hundreds of millions of people at risk.
As gloomy as this sounds, we just don’t know how bad it will be. Accurate predictions are difficult because none of our current models take into account all of the effects that warmer temperatures are having throughout the ecosystem. “The models can estimate reasonably well how the oceans will expand as temperatures rise, and how much melting is taking place, but none take into account the effect of melting on the rate at which land ice is moving to the sea.” This is important because sea levels rise when land glaciers break off into the ocean; ice that is already in water – such as Arctic sea ice – does not boost sea levels when it melts.
There are also important “feedback” effects that are difficult to measure. As Arctic sea ice melts, says Scott Munro, a retired geography professor at U of T Mississauga who specialized in climate and glaciers, the amount of solar radiation being reflected back into space decreases, causing more ice to melt. “The less ice there is, the less likely it is to sustain itself.” Just a few years ago, scientists were predicting an ice-free Arctic in the summer by mid-century; some now think it could happen by the end of this decade.
So yes, global warming is dangerous. But civilization-ending? That depends. The psychological burden of forced relocation on 100 million people is troubling; the estimated economic costs, staggering. According to a 2009 report by World Wide Fund For Nature/Allianz, just a half-metre rise in the oceans by 2050 – would put $28 trillion in assets at risk in the world’s 136 port mega-cities, including New York, Miami and Shanghai. (By comparison, Hurricane Katrina, the costliest natural disaster in American history, caused about $110 billion in damage; Hurricane Sandy, $60 billion.)
The one bright side, if it can be called that, is that it would take millennia of higher temperatures for Antarctica, with its vast ice sheets, to melt completely. That scenario would raise sea levels by about 60 metres and wipe entire countries off the map. More imminent – though still centuries away – is a complete melting of the Greenland ice cap, which would raise sea levels by about seven metres.
What’s most troubling about this “incremental apocalypse,” says Munro, is that we know it’s coming, but seem incapable of preventing it. And the longer we wait, the worse it gets (even if carbon emissions were stabilized now, the seas would continue to rise for some time). The solution is easy to state, stubbornly difficult to enact: “We have a carbon-based economy, and we have to decarbonize it,” he says. “Our whole way of life has to change.” – SA
Small bits of debris constantly fall on Earth; it’s the city block–sized chunks of rock we need to worry about
A million to one. Those are the actual, estimated odds that, sometime in your lifetime, you’ll be killed by an asteroid hurtling in from space. “That’s comparable to the risk of dying from a fireworks explosion or terrorism,” says Michael Reid, co-ordinator of education and public outreach at U of T’s Dunlap Institute for Astronomy and Astrophysics. “It’s surprisingly small!”
That’s because rocks big enough to wipe out most life only rarely collide with Earth. “Roughly every 100 million years, something [like that] comes along,” says Reid. The most recent, 65 million years ago, killed 20 to 70 per cent of all species, including the dinosaurs. The 10-kilometre asteroid smashed down on Mexico, so red-hot from whipping through the atmosphere that it exploded even before it hit the ground – with the force of a billion atomic bombs. Scary, but it gets worse. “The problem is the amount of dust that gets scattered into the atmosphere,” says Reid. “It darkens the skies and kills the plant life. Then everything high up on the food chain winds up dying because there isn’t enough food.”
Even smaller asteroids can pack a punch. In 1908, a 25-metre fireball, as powerful as 185 atom bombs, flattened trees for 50 kilometres around the Podkamennaya Tunguska River in Siberia. The United States Space Command reported that a nuclear-scale explosion over the Mediterranean Sea in June 2002 was probably a five- or 10-metre asteroid. Though one-metre rocks “are very common,” says Reid, “a lot of those burn up in the atmosphere. And every moment, there’s a grain of sand falling from space.”
Around the world, teams of astronomers are patiently looking for and tracking the millions of asteroids that whiz perilously past our planet each year. It’s not an easy task. “We believe there are about 1,000 near-Earth asteroids larger than one kilometre, of which we have detected about 90 per cent,” says Reid, but “we estimate that there are maybe one million near-earth asteroids larger than about 60 metres, and we’ve located fewer than 10,000 of those. There is a lot of work left to be done.” That’s why the Canadian Space Agency’s NEOSSat (Near-Earth Object Surveillance Satellite) was launched in December: to sweep the skies for asteroids, falling satellites and other space debris. If we do spot an incoming asteroid months or years in advance, we might even have the technology to avert the “rockalypse.” “As far as I know,” says Reid, “the more fantastical scenarios about sending a nuclear missile and blowing an asteroid up will probably not work. You could send a probe that would land on it, and fire an engine that would gently nudge the rock out of the way. You could paint one side, and reflecting sunlight can push it out of the way.”
Ultimately, another giant asteroid will be on course for our planet. It’s “just a question of time” says Reid’s colleague Peter Martin, a professor at U of T’s Canadian Institute for Theoretical Astrophysics. But in the next century? Unlikely,” he says. “The big ones are rare,” adds Reid. – JR
Storms on the sun can shut down electronics on Earth
On August 28, 1859, a solar flare pulsed on the sun, sending ions and electrons whizzing earthward. When the magnetic storm arrived, northern lights blazed over the Caribbean, and the fledgling telegraph network shut down (complete with flying sparks). Pretty, but hardly perilous. Then. The trouble is, solar flares happen often. On November 13, 1960, a flare blanked radio broadcasts around the world. On March 13, 1989, a flare half the intensity of 1859 took down the Hydro-Québec grid in seconds, leading to a nine-hour blackout. What would happen to our satellite-linked, electricity-dependent, world of today if we get another really big solar storm?
Economic chaos. Ray Jayawardhana, a professor in U of T’s department of astronomy and astrophysics, says a report by the National Academy of Sciences in the US estimated a “once-a-century” solar storm – one not nearly as strong as 1859 – “could have an economic impact 20 times that of Hurricane Katrina. Trillions of dollars.” Civilization destroying? Probably not. But massively disruptive.
And the odds of the next powerful flare coming on December 21? There’s no way to predict that, says Jayawardhana. The 1859 event is “still the strongest solar storm on record,” – meaning events like it could happen every few hundred years, or even less frequently. We can’t tell, because there’s really no pattern to solar flares.
Still, we’re learning. Hydro-Québec updated its systems after 1989, and because space agencies watch the sun, we’ll always get at least a few hours warning of the ions’ arrival. If there’s the political will to do so, we could pre-emptively power down parts of the grid to reduce potential damage, says Jayawardhana. “Even for relatively minor storms,” he points out, “some of the more sensitive astronomical observatories in space get shut down at least a couple of times a year.” – JR
The world’s economy runs on fossil fuels. But an empty tank is not the chief of our worries
Running out of oil is a problem for the world, but not in the way most people think, says John Kirton, a professor of international relations at the Munk School of Global Affairs. Oil scarcity doesn’t make his short list of apocalyptic scenarios, but he acknowledges that it could hasten – or exacerbate – a war involving nuclear-armed combatants.
On the issue of scarcity itself, Kirton is unabashedly optimistic. He believes the world has already embarked on a gradual and manageable transition away from oil to a broader suite of fuels. These include natural gas and electric power (for vehicles), and nuclear power and renewables such as wind, solar, biomass and hydroelectric (for heating).
So are those who have been promoting the “peak oil” theory wrong? Yes and no. In Kirton’s view, there’s little doubt that the supply of relatively cheap high-quality crude oil that we’ve been using for the past century has peaked – or soon will. But he observes that, as oil prices have risen, new supplies have come on stream. The U.S. and France are undertaking major developments of shale gas and oil and Canada’s tar sands have become the “Saudi Arabia for heavy oil.” These additional supplies, he says, will help ease the transition to a less oil-dependent economy. He believes conservation will also play an important role as automakers build more fuel-efficient cars, including electric and hybrid models, in response to stricter American standards coming into effect by 2016.
A complete transition away from oil will take until at least mid-century, though, and in the meantime, oil dependency is real and could be a factor in geopolitical conflicts. As an example, Kirton conjures a scenario based on recent events in which China imposes a naval blockade of Japan over a territorial dispute that could eventually draw in Taiwan, the Koreas and Russia. Although the genesis of a war would probably be territorial, oil – or the lack of it in a blockaded Japan – could quickly escalate the conflict. “This would be the world’s second- and third-largest economies going to war with nuclear weapons in the mix,” says Kirton. “We have no recent historical experience about how to handle this.” Alternatives to oil exist; the question, then, is how smoothly we can make the transition. – SA
Red Giant Sun
The sun won’t live forever – so neither will our planet
If humans do survive the many problems of our own making, we will eventually face a naturally occurring doozy – a life-ending problem so big, we’ll have no choice but to flee the planet. At some point in the distant future, our sun will become too hot for life on Earth.
This is not a new problem: the sun is already about 30 per cent brighter than it was when the Earth formed 4.5 billion years ago. And, according to Ray Jayawardhana, a professor in the department of astronomy and astrophysics, we have about another billion years before most of the surface water on our planet turns into steam.
Even then, our cosmic evolution won’t be done. About six billion years in the future, the sun will finish converting the hydrogen in its core into helium and will start burning hydrogen in a shell around the core. Its outer layers will swell into a huge globe 100 to 200 times the sun’s current size – a red giant star. “It’s likely to engulf Mercury and Venus, and come pretty close to the Earth’s orbit for a bit,” says Jayawardhana. “It’s likely any kind of life we could think of today wouldn’t survive.”
Once earth is crisped and the sun reaches the end of its red giant phase, our star’s core will collapse into a white dwarf, an “incredibly dense stellar cinder,” says Jayawardhana. As it cools over another few billion years, so will our planet, until Earth is a frozen, rocky wasteland. The end.
“It’s a pretty dismal future in the very long run!” laughs Jayawardhana. Or, it’s simply a deadline: roughly a billion years to figure out interstellar travel! – JR
By bringing artificial intelligence into chemistry, Prof. Aspuru-Guzik aims to vastly shrink the time it takes to develop new drugs – and almost everything else