dimanche 2 octobre 2011

le pic du pétrole et la santé publique ( en anglais)

by Mike Field


It was the easy oil—that’s what fueled our prosperity.

Economists associate the availability of abundant inexpensive energy with economic growth, suggesting that the modern era’s rising tide of global wealth—and health—was borne up largely on a sea of cheap oil. “We’ve been living for 150 years on a fossil fuel bubble,” is how Stuart Chaitkin, MA, a retired energy policy analyst and senior associate in Environmental Health Sciences (EHS), describes the current situation. “You can’t just simply replace oil for many of its uses. Oil is the world’s master resource.”

But what happens when the supply of that master resource can no longer keep pace with demand? Despite tremendous increases in demand for oil during the economic boom from 2005 to 2009, world production during that period was generally flat, leading to the record-breaking $147 per barrel cost of oil reached in July 2008. This experience exemplifies the concept of “peak oil,” the idea that because petroleum is a finite nonrenewable resource, at some point maximum possible production will be reached—and thereafter the number of barrels of oil pumped worldwide each year will decline steadily, with a resulting significant rise in prices.

Oil was cheap only so long as it was plentiful and easy to extract, but in tandem with growing demand from emerging economies like those in China and India, more and more of remaining “non-conventional oils” are locked in tar sands or buried deep under the ocean’s bed. This tough oil will be costly oil, presenting enormous challenges to everything from transportation to food production—and ultimately, to global public health.

“There are no solutions, only responses,” says EHS professor Brian Schwartz, co-director of the Program on Global Sustainability and Health and a nationally recognized expert on the health consequences of peak oil. “You can deny climate change forever, but you can’t deny the rising price of oil. The limitations to ever-increasing production are a geologic reality.”

The coming era of petroleum scarcity is “probably the most underreported issue of our time,” says Schwartz, MD, MS. He and Bloomberg School colleagues have spent much of the past decade looking at how ever-more-costly petroleum will affect some of the key drivers of public health, and what strategies we should adopt now to minimize future health consequences. (Schwartz and Cindy Parker, MD, MPH ’00, an EHS assistant professor, were guest editors for a special issue on peak oil’s far-reaching impacts on health in September’s American Journal of Public Health.) Schwartz says the immediate challenge is simply making people aware of what’s headed our way: “Until we acknowledge the problem, there will be no will to develop responses.”

The five key areas that follow illustrate the potential health fallout of petroleum scarcity.

1. Economic Instability

The Japanese coined a word—oirushokku or “oil shock”—for the wrenching consequences of the 1973 OPEC oil embargo that caused the price of oil to quadruple to $12 a barrel. Sudden large increases in the price of oil present an enormous economic challenge; as the Japanese understood, they shock the system. Some economists claim spiking oil prices caused four of the last five global economic recessions. And, says Parker, co-director of the Program on Global Sustainability and Health, economic decline is bad for public health: “Health outcomes decline when the economy declines. People make ends meet at the expense of their health, and societies reduce health benefits when budgets are tight.”

At the extreme of this correlation is the former Soviet Union which, since the fall of communism and the collapse of its economy more than two decades ago, has experienced an increase in mortality and some kinds of morbidity unprecedented for an industrialized nation at peace. At the peak of the economic crisis in the mid-1990s, the country was experiencing its highest peacetime death rate in the 20th century; the incidence of tuberculosis, brucellosis, diphtheria and syphilis had increased dramatically and in the case of the last two diseases more than doubled. The country also witnessed the return of epidemic diseases such as cholera and typhoid fever. Ironically, it was the wealth generated by Russia’s vast oil and natural gas reserves that eventually enabled the country to reverse its economic decline—though health indices for Russians continue to lag far beyond those of their European neighbors.

Budget shortfalls brought about by recession and declining government revenues will inevitably have a strong effect on research funding as well, threatening the next generation of advances in medicines, vaccines, preparedness and knowledge that could most effectively advance the global public health agenda.

2. Food Scarcity

From fossil fuel–derived fertilizers and pesticides, to diesel-powered tractors and water pumps, to an elaborate long-distance transport system, oil is something that—in a very real sense—we eat. Because modern agriculture has become so dependent upon oil, petroleum scarcity leads to significantly higher food prices and outright shortages, and was at least partially responsible for the global rice shortage of 2008, when oil reached record high prices. “The poor are exquisitely sensitive to food prices,” notes Peter Winch, MD, MPH, International Health professor. The United Nations Food and Agricultural Organization estimates that more than 900 million people worldwide are undernourished, a number more than 100 million greater than before the oil-fueled food price increases that began around 1997. Increased food insecurity—and even outright famine—would likely result from any additional large increases in the price of oil.

“I think food is the biggest issue of all,” says Melissa Poulsen, a PhD student in International Health, whose research is focused on identifying populations most vulnerable to global petroleum scarcity and how best to help them. “Any disease is irrelevant if you are without a secure food source. Good nutrition is critical to health; you have to eat.”

In yet another ironic twist, those same forces in developed nations might tend to favor improved nutrition. As rising oil prices make it prohibitive to transport highly processed (read: unhealthy) foodstuffs over long distances, and consumption declines, people may be forced to turn to more locally based, sustainable agriculture.

3. Clean Water Decline

In some areas, petroleum is an ingredient necessary to the availability of clean water. A European Union report from earlier this year called attention to looming water shortages in the Middle East, which until now has used its access to abundant cheap petroleum to produce plentiful water for its citizens. Libya has spent $20 billion pumping water from deep beneath the desert in so-called “fossil water” reservoirs that cannot be replenished; no one knows how much longer they will last. Saudi Arabia has seen water use surge by 500 percent since 1985. Increasingly, all countries in the region are turning to desalination; more than 1,500 plants now line the Gulf and the Mediterranean and provide much of the drinking water for North Africa and the Middle East—and two-thirds of the world’s desalinated water.

Meanwhile, the world’s regions most desperately short of clean water—Asia and Africa—are making plans to greatly increase their use of desalination. But the energy to power these plants typically comes from oil, and for those countries that have to import petroleum—such as Egypt, which will soon turn from a net exporter to importer as its oil fields play out—the cost of water could begin to reflect the cost of oil. In Saudi Arabia, 28 desalination plants provide 50 to 70 percent of the current drinking water supply, using 1.5 million barrels of oil per day, notes Cindy Parker. “Oil exporting nations may soon decide to reduce their exports to importing countries in order to use their oil for vital national purposes such as water desalination,” she says. “Importing nations, such as the U.S., will be especially vulnerable because we rely so heavily on oil exports to run our entire economy.”

4. Transportation Challenges

“The transport system is the first to feel the effects of petroleum scarcity and increasing price,” says Schwartz. This includes the complex supply chain for drugs and medical equipment that often spans countries and even continents. In developing countries, the World Bank has found that high cost and limited availability for patient transport is a major impediment to reaching the Millennium Development Goals for maternal and child mortality. Energy insecurity and costs could also hinder or even prevent international relief organizations from responding rapidly and effectively to humanitarian emergencies. Fundamentally, all efforts in disaster relief are giant challenges in logistics and transportation; every additional dollar spent on fuel is that much not spent on the food and clean water, shelter and medicines that must be delivered to the scene of a disaster.

In developed nations, routine medical delivery could be affected. Most petroleum used in the U.S. for instance, is for transportation, accounting for 70 percent of all oil use in 2008. Moreover, the U.S. transportation system would be at a standstill without oil; more than 90 percent of all transportation sector energy is derived from oil. America’s centralized medical centers require both patients and workers to transport themselves to the site, often over considerable distances. It goes without saying that ambulances, emergency airlifts and public health outreach all depend on petroleum.

Many researchers have argued that it is only cheap energy that has allowed the incredible specialization we see in our health care system. According to Schwartz, in an era of tough oil, “communities are going to have to reorganize and if they do not, we will see the same difficulties in providing care to persons in suburbs in the future that we see today in providing care to those in rural areas—a very well-known problem. Most patients get to the doctor by using petroleum; if that petroleum is very expensive, something will have to change or else there will be no doctor visit.”

5. Environmental Effects

Extracting and processing the “tough oil”—oil from beneath the sea, or tar sands, or shale deposits or the vast supplies of heavy oil known to exist in Saudi Arabia—involve using ever more energy-intensive technology to produce each additional barrel of oil. Increasingly, remaining oil reserves will be in the form of this “nonconventional oil” that is both expensive and dirty. “It takes a huge amount of energy and effort to produce and process this oil, and environmentally it can be tremendously damaging,” says Stuart Chaitkin. U.S. oil production illustrates the law of diminishing energy returns as oil resources play out. In 1930, the energy return on energy invested (EROEI) in U.S. oil fields was 100:1; that dropped steadily to 40:1 by the time U.S. domestic oil production peaked in 1970. Today that figure is down to 14:1 and it’s expected to continue to decline. “Nonconventional oil sources are dirty,” says Cindy Parker simply, “and if we make the choice to exploit them heavily we can actually accelerate carbon emissions and global warming, along with the many negative health consequences that will bring.”



Editorial Notes


Re-posted with the kind permission of Johns Hopkins.
-BA


Original article available here

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The Conversation



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—Roger Sessions

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