The Natural ressources Dilemma

So what exactly is the state of our planet’s natural treasure-trove? Under the pressure of the economic and demographic expansion of the countries of the South and of Asia, the first thing that springs to mind is the fear of an oil shortage. “We’re a long way off that,” explains Gilles Rotillon, a professor at the University of Paris-X and a researcher at the EconomiX laboratory.¹ “We’re close to expensive oil, but it remains affordable. Twenty-five years ago in France, a liter of gasoline was worth thirty minutes of the basic minimum wage; it’s worth three times less today.” Michel Cathelineau, from G2R² in Nancy agrees: “Reserves are an economic concept. When prices rise, technology improves and new oilfields are exploited. But it’s true that the age of easily extracted oil is coming to an end.” As an example, Cathelineau brings up the Canadian bituminous sands, which are rich in petroleum but difficult to exploit. One idea is to use steam produced by small nuclear powered units to extract the heavy oils. In addition, a deposit that has been “worked dry” actually still contains 20 to 80% of the initial stock. The production can be revived by reinjecting the gases extracted from the wells–especially CO₂–thus reducing the ecological impact at the same time. “A 1% increase in the output of all the known deposits is equivalent to one year of global consumption,” Rotillon points out. Faced with climate change, we’ll also have to learn how to sequester the CO₂ from thermal power stations. This should also be applied to coal, a big CO₂ emitter, but which has huge reserves.

Uranium and Metals
The battle against global warming, together with an energy-hungry China, is giving new respectability to nuclear energy, and is upsetting worldwide energy markets. In just four years, the price of uranium has increased tenfold. “There’s no risk of a shortage in the short term,” says Cathelineau. “Current deposits should last for the next 20 years or so. What’s more, the rise in prices has renewed interest in exploration.” If worst comes to worst, there’s always the ocean, which contains vast amounts of uranium, but in tiny concentrations. Just 3 micrograms per liter, compared to the 10% content of the highest-grade ores extracted. “It’s feasible, but very costly with regard to energy. The cost price would probably range between $500 and $1000 per kilo, versus today’s average of $100/kg.” The economics of iron ore obeys the same laws as petroleum and uranium. After high-grade deposits are exploited, the rise in prices will open up new prospects for extraction in lower-grade sites. “Not forgetting that if prices increase too much, we can recycle,” Cathelineau observes. As for copper and gold, there are probably massive deposits that have yet to be discovered.

Geothermal Energy
The ground is also a source of heat, unevenly spread around the planet. There are the traditional geothermal power plants, like the one in Guadeloupe’s Bouillante commune whose turbines are powered by the steam that gushes forth from the volcanic rocks. A more recent process is used at Soultz-sous-Forêts, in Eastern France, where the rock is fractured and water is then pumped underground, where it heats up to 150°C at a depth of 1.5 km.
But researchers are also turning to the high energies found in tectonically active areas. “In Iceland, we are working with industrial partners,” says David Mainprice, from the Geosciences laboratory in Montpellier. “The drill hole has currently reached a depth of 3 kilometers–aiming for 5 kilometers. The objective is first and foremost a scientific one, namely the observation of the mid-oceanic ridge,³ but it’s also a trial run for high-temperature drilling techniques.” The water, at a temperature of 400°C, could produce electricity that would then be exported to Europe by a submarine cable. The supercritical state of the water–half liquid, half gas–also means that it could be used to dissolve and bring up the metals present in the underlying rocks. This would be somewhat of a hybrid between a power plant and a mine.

Managing precious Water
If the Earth isn’t yet short of energy or raw materials, water is quite a different matter. “We’re going to have to manage water resources,” warns Philippe Davy, senior researcher at the Geosciences unit in Rennes.⁴ “We need to know the structure of the aquifers. And to do this, we need to design new imaging methods. This will help us not only plan the management of water deposits, but also protect them against surface pollutants.”
Yet, if we look at the planet as a whole, there’s no lack of water, explains Ghislain de Marsily. “The real issue is the disparity between water resources and the distribution of the population. Arid regions are home to 20% of mankind, and yet only have 2.2% of the global water supply.” What’s more, in most parts of Africa, water is naturally abundant but not readily available, due to the lack of infrastructure required to manage it. “That’s where 850 million people suffer from malnutrition. On the other hand, in the regions of the planet where there is a physical lack of water, people aren’t dying of hunger, because they have the means to import food.” Engineers and scientists are exploring new avenues, like the “great artificial river”, or submarine fresh water springs, mainly in the Mediterranean. “We still don’t know how to recover drinking water, but drinking water will in most cases never be an issue, only a small amount is needed. What is lacking are water treatment plants, distribution systems, and waste water collection and treatment. The water that is really in high demand is for agriculture. And desalination isn’t capable of solving the problem of feeding the world either.”
According to de Marsily, the answer is to reorganize the world’s agricultural production. But giving up food self-sufficiency won’t be easy, especially as global warming leads to more frequent droughts, and the possible return of famines. “In 1998, during an intense El Niño event,⁵ China and Indonesia exhausted world food stocks,” de Marsily points out. What would happen if India or Brazil were hit by drought at the same time as the two Asian giants, as happened twice in the 19th century?

Restoring Natural Capital
For James Aronson, a researcher at CEFE,⁶ all this proves that there’s an urgent need to undertake a complete rethink. “Every year, we already consume 30% more than the Earth can produce.” In other words, the land is overexploited, and we’re exhausting the stocks of natural resources without giving them the time to recover. And this is only the beginning: “In 2050, with 9 billion inhabitants, we’re going to need the equivalent of three planet Earths,” explains Aronson. This exponential increase can be explained in particular by the rise in average living conditions on the planet, and the westernization of certain ways of life. “We have now entered the Anthropocene, the first geological epoch primarily influenced by humankind,” Aronson remarks.
Aronson, like the other hundred professionals who are members of the Restoring Natural Capital Alliance,⁷ defends the idea of a happy medium between the fundamentalism of Deep Ecology, which considers humans to be harmful, and that of the “neoclassical economy,” which sees nature–and often humans–simply as productive machines. “We must put humans back in the place they occupy in nature, and restore ecosystems, which offer a host of resources: water, air, energy, food, and raw materials. Only a well-adjusted ecosystem and a complimentary relationship between humans and their natural habitat can ensure both sustainable production and a decrease in poverty.
Behind the words are concrete measures, with the twin goals of protecting the environment and providing jobs for local populations. For instance, there’s the “payment for ecosystem services” in the Drakensberg Range, between South Africa and Lesotho. “This impoverished region holds 25% of South Africa’s water reserves. The idea is to pay for the restoration and better management of natural and cultivated ecosystems by taxing water in large cities.” Another project, in Madagascar, aims to preserve and regenerate forests, creating jobs for local villagers. This is better than setting up sanctuaries over 5 or 10% of the area of a country and overexploiting the rest. A promising new way of living in harmony with our planet.

Denis Delbecq

Clean Energy from the Ocean Floor Have we found an energy source able to produce hydrogen without using petroleum or emitting greenhouse gases? Bruno Goffé, deputy director of INSU, would very much like to know the answer: “IFREMER has recently shown that the hydrothermal vents on mid-ocean ridges could be major sources of natural hydrogen.” These oceanic vents spew out gas under pressure, containing 40-50% of pure hydrogen. “It’s produced by the reaction of sea water with iron-rich rocks from the Earth’s mantle, at high temperatures and in the absence of oxygen,” Goffé explains. “There’s still a lot left to discover about these vents: their mechanisms, distribution, duration, etc.” INSU, together with IFREMER has launched a broad study into the subject to try and understand how such vents work, identify them and reproduce them in the laboratory. Seven CNRS teams have already answered the call. Meanwhile, Goffé is imagining future hydrogen power plants, which would use iron oxides–extremely abundant in the Earth’s crust–and water, with the necessary heat being provided by the Sun. “Using this method, we could get the equivalent of 120 liters of gasoline from a ton of basalt and 150 liters of sea water,” he reckons. D.D. Contact : Bruno Goffé, bruno.goffe@cnrs-dir.fr

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Production: CNRS Images, Planet Risk
Language: English and French
The TSUNARISK research project studied the impact of the December 26th, 2004 tsunami, the most destructive ever to hit the coastlines of the Indian Ocean.

> In the Climatic Depths (2006, 26’)
By Claude Delhaye and Luc Ronat
Production: CNRS Images, Eur-Oceans, Cnes
Language: English, German and French
The oceanographic expedition Drake investigates the Antarctic Circumpolar Current, the most powerful ocean current on our planet.

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