Crowded Earth: how many is too many?

Already straining to host seven billion souls, Earth is set to teem with billions more, and only a revolution in the use of resources can avert an environmental crunch, experts say.

As early as 1798, Thomas Malthus gloomily forecast that our ability to reproduce would quickly outstrip our ability to produce food, leading to mass starvation and a culling of the species.

But an industrial revolution and its impact on agriculture proved Malthus and later doomsayers wrong, even as our numbers doubled and redoubled with accelerating frequency.

"Despite alarmist predictions, historical increases in population have not been economically catastrophic," notes David Bloom, a professor in the Department of Global Health and Population at Harvard.

Today, though, it seems reasonable to ask if Malthus wasn't simply a couple of centuries ahead of the curve.

On October 31, the world's population is officially scheduled to hit seven billion -- a rise of two billion in less than a quarter century.

Over six decades, the global fertility rate has roughly halved, and amounts to a statistical 2.5 children per woman today.

But this varies greatly from country to country. And whether the planet's population eventually stabilises at nine, 10 or 15 billion depends on what happens in developing countries, mostly in Africa, with the fastest growth.

As our species has expanded, so has its devouring of the planet's bounty, from fresh water and soil richness to forests and fisheries.

At its current pace, humankind will need, by 2030, a second planet to satisfy its appetites and absorb its waste, the Global Footprint Network (GFN) calculated last month.

And through the coal, oil and gas that drive prosperity, we are also emitting greenhouse gases that alter the climate, potentially maiming the ecosystems which feed us.

"From soaring food prices to the crippling effects of climate change, our economies are now confronting the reality of years of spending beyond our means," GFN's president, Mathis Wackernagel, said.

French diplomat Brice Lalonde, one of two coordinators for next June's UN Conference on Sustainable Development, dubbed "Rio+20," said Earth's population rise poses a fundamental challenge to how we use resources.

"In 2030 there will be at least another billion people on the planet," Lalonde said.

"The question is, how do we boost food security and provide essential services to the billion poorest people but without using more water, land or energy?"

This is why, he said, Rio+20 will focus on practical things such as increasing cleaner sources in the world energy mix, smarter use of fresh water, building cities that are environmentally friendlier and raising farm yields without dousing the soil with chemicals.

But such options dwell far more on the impact of population growth than on the problem itself.

Braking fertility rates would help the human tally stabilise at eight billion and haul poor countries out of poverty, ease the strain on natural resources and reduce climate vulnerability, say advocates.

For some experts, voluntary birth control is the key.

Geoff Dabelko, director of the Environmental Change and Security Programme at the Woodrow Wilson Center in Washington, cites Somalia as a case study of what happens when women have no access to contraception.

Racked by civil war and poverty, its population is projected to grow from about 10 million today to 22.6 million by 2050. It has the eighth-highest birth rate in the world and an average of seven children per family.

Even before the country fell into a full-fledged crisis, a third of its children were severely underweight, according to UNICEF. Ninety-nine percent of married Somali women have no access to family planning.

Many economists, though, argue that the answer lies more in reducing poverty and boosting education, especially of women.

A 2010 study in Colombia found family planning explained less than 10 percent of the country's fertility fall. The real driver was improved standards of living.

Even so, at summits that seek to shape Earth's future, tackling population growth head-on is almost taboo.

"When I attended the UN environment conference in Stockholm (in 1972), the No. 1 item on the agenda was out-of-control population growth," recalled Paul Watson, head of Sea Shepherd Conservation Society, a radical green group.

"When I attended the 1992 conference (in Rio), it wasn't even on the agenda. No one talked about it any more."

Demography was similarly absent from the UN's 2002 Johannesburg Summit, when Earth's population had climbed to six billion.

Why does "how many is too much" remain absent from the top tables?

One perceived reason is the opposition by religious conservatives to contraception or abortion. Politicians, too, may see no mileage in addressing an issue that will only cause them headaches and yield benefits several decades away.

But for some critics, population measures are synonymous with the mistakes of coercive sterilisation in India in the 1970s or China's "one child" policy, which has led to a gender imbalance in favour of boys.

Global oil reserves and fossil fuel consumption

The world is showing no sign of weaning itself off fossil fuels: in the 28-year span covered by the BP data below, worldwide reserves of oil fell only twice – in 1998 and 2008.

Oil has been the world's fossil fuel of choice since the late 1960s and our taste for it doesn't seem likely to diminish in the short term. Oil companies are still keen to secure any undiscovered reserves while continuing to be a powerful lobbying presence. You may think that with pressing concerns over peak oil and global warming, the world would be slowly weaning itself off the energy-rich liquid. But in the 28-year span covered by the BP data below, worldwide reserves fell only twice – in 1998, and a decade later in 2008.

Opec nations control the lion's share, with 76% of the world's reserves. Interestingly, many of the Opec countries' proven reserves have barely changed in the past 20 years, despite massive exporting activity.

The largest percentage growth in oil wealth is in Vietnam, with a 39% surge in its proven oil reserves from 2007-08. This newfound wealth corresponds to 1.3bn barrels, which may sound like a lot, but would feed the world demand for less than three weeks (17 days) at 2008 levels of consumption.

Oil consumption fell by 0.29% from 2007-08, while its more polluting relation coal saw a 3% increase in its use. Reasons for coal's recent rise include the low price of emissions trading permits and the fuel's increasing promotion as key for 'energy security'.

Australia may be getting a glimpse of its globally warmed future

Experts agreed Tuesday that no one drought, flood or wildfire can be attributed to global warming, but they stressed that the eucalyptus forest and farms of southeastern Australia are becoming warmer, drier and more prone to fire as the planet heats up.

Some say rising temperatures are making Australia's climate more extreme at the edges. Snow will disappear from the few mountains that still have it, the cyclones that batter the topical north could get more powerful and the conditions that set the southeast ablaze could become common.
"The terrible events of the past couple of weeks are, without doubt, partly the result of global warming and the greenhouse effect," said Neville Nicholls, an expert on climate change and wildfires at Australia's Monash University.

Global warming cannot be blamed for starting the hundreds of recent fires — tens of thousands of such blazes erupt across Australia every fire season, from October to March — but the effects of climate change exacerbated their ferocity, Nicholls said.

First, a decade of drought has made Australia's wild forests — known as "the bush" — tinder dry. Second, a sustained and record-breaking heat wave settled over the region. Lastly, record-smashing temperatures on Saturday topped 117 degrees Fahrenheit (47 degrees Celsius) and combined with winds up to 60 mph (100 kph) to whip fires into furnace-like intensity.

The Intergovernmental Panel on Climate Change, the Nobel Prize-winning team of scientists responsible for advising the United Nations about global warming, says the rise in the atmosphere's temperature could cause water shortages, crop failures, more deaths from heat waves and more severe storms around the world.

In Australia, it means more droughts in the dry south and more flooding in the tropical north. The Great Barrier Reef, the world's largest coral reef system rich in sealife and sensitive to small temperature changes, is in trouble.

The Australian government's Commonwealth Scientific and Industrial Research Organization concluded in 2007 that the country's average temperature will rise about 1.8 degrees Fahrenheit (1 C) by 2030 and up to 9 degrees F (5 C) by 2070 if greenhouse emissions are not curbed.
An island large enough to be counted as a continent, Australia's climate varies with its landscape. It is home to dry shifting dunes in the desert "red heart," misty Riesling grape-clad hills, and lush monsoonal rain forest and mangrove swamps.

Among the panel's forecasts: Climate change would likely mean less rain, but rainfalls that did occur would be more intense. Drought in the south — the wheat-, sheep- and cattle-growing food belt — would be more frequent and fires more common. Cyclones that are a regular feature of the summer months in the north would hit harder.

Even as southeastern Australia sweltered and the fires raged this week, some 60 percent of northeastern Queensland state was covered by floodwaters after weeks of drenching rain from a dying offshore cyclone. Three thousand homes were damaged. No deaths were reported.
While scientists cautioned against attributing the wildfires themselves to global warming, they said changing conditions from rising temperatures are having an impact.

"Australia — and particularly the southeastern corner of Australia — is fire prone, so a fire-prone environment coupled with a warmer and drier climate in the future is likely to increase the incidence of this kind of event," said Mark Adams, a wildfire expert at the University of Sydney. "But statistically, we won't be able to prove it for many decades."

Adams said Australia's peculiar ecosystems are particularly susceptible to the effects of climate change. An increase of just one or two degrees would cause snow in Australia to disappear, and its Great Barrier Reef and rainforests are particularly sensitive to warming, he said.

"But I don't think that on the whole Australia is more susceptible than many other — or indeed any other — continent," Adams said.

Penny Whetton, leader of the climate change research group at Commonwealth Scientific and Industrial Research Organization, also cautioned against tying the fires too closely to global warming.
"Due to changes in the climate, the high risk of fires has increased and will increase," she said. "But that is different than saying climate change caused these fires. It's difficult to relate climate change to an individual weather event."
For conservationists, the dry conditions and the devastating fires bolster their campaign to push the world's governments to move faster on reducing emissions of greenhouse gases.
"It's a sobering reminder of the need for this nation and the whole world to act and to put at a priority our need to tackle climate change in a way that politicians have simply been unable or refused to do in past decades," said Sen. Bob Brown of the left-leaning Australian Greens party.