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Emerging water shortages
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It is often said that future wars in the Middle East will more likely be fought over water than oil, but in reality the competition for water is taking place in world grain markets.

The countries that are financially the strongest, not necessarily those that are militarily the strongest, will fare best in this competition.Knowing where grain deficits will be concentrated tomorrow requires looking at where water deficits are developing today.Thus far, the countries importing much of their grain have been smaller ones. Now we are looking at fast-growing water deficits in both China and India, each with more than a billion people.

As noted earlier, overpumping is a way of satisfying growing food demand that virtually guarantees a future drop in food production when aquifers are depleted.

 

Many countries are in essence creating a “food bubble economy”—one in which food production is artificially inflated by the unsustainable mining of groundwater.

 

At what point does water scarcity translate into food scarcity? David Seckler and his colleagues at the International Water Management Institute, the world’s premier water research group, summarized this issue well: “Many of the most populous countries of the world—China, India, Pakistan, Mexico, and nearly all the countries of the Middle East and North Africa— have literally been having a free ride over the past two or three decades by depleting their groundwater resources.

The penalty for mismanagement of this valuable resource is now coming due and it is no exaggeration to say that the results could be catastrophic for these countries and, given their importance, for the world as a whole.”

Since expanding irrigation helped triple the world grain harvest from 1950 to 2000, it comes as no surprise that water losses can shrink harvests. With water for irrigation, many countries are in a classic overshoot-and-decline mode.

 If countries that are overpumping do not move quickly to raise water use efficiency and stabilize water tables, then an eventual drop in food production may be inevitable.
 
Worrying Glacial retreat
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One of the largest glaciers in Antarctica is thinning four times faster than it was 10 years ago, according to research.

A study of satellite measurements of Pine Island glacier in west Antarctica reveals the surface of the ice is now dropping at a rate of up to 16m a year.

Since 1994, the glacier has lowered by as much as 90m, which has serious implications for sea-level rise.

The work by British scientists appears in Geophysical Research Letters.

The team was led by Professor Duncan Wingham of University College London (UCL).

“ We've known that it's been out of balance for some time, but nothing in the natural world is lost at an accelerating exponential rate like this glacier ”
Andrew Shepherd, Leeds University

Calculations based on the rate of melting 15 years ago had suggested the glacier would last for 600 years. But the new data points to a lifespan for the vast ice stream of only another 100 years.

The rate of loss is fastest in the centre of the glacier and the concern is that if the process continues, the glacier may break up and start to affect the ice sheet further inland.

One of the authors, Professor Andrew Shepherd of Leeds University, said that the melting from the centre of the glacier would add about 3cm to global sea level.

"But the ice trapped behind it is about 20-30cm of sea level rise and as soon as we destabilise or remove the middle of the glacier we don't know really know what's going to happen to the ice behind it," 

"This is unprecedented in this area of Antarctica. We've known that it's been out of balance for some time, but nothing in the natural world is lost at an accelerating exponential rate like this glacier."

Pine Island glacier has been the subject of an intense research effort in recent years amid fears that its collapse could lead to a rapid disintegration of the West Antarctic ice sheet.

Five years ago, I joined a flight by the Chilean Navy and Nasa to survey Pine Island glacier with radar and laser equipment.

The 11-hour round-trip from Punta Arenas included a series of low-level passes over the massive ice stream which is 20 miles wide and in places more than one mile thick.

Back then, the researchers on board were concerned at the speed of change they were detecting. This latest study of the satellite data will add to the alarm among polar specialists.

This comes as scientists in the Arctic are finding evidence of dramatic change. Researchers on board a Greenpeace vessel have been studying the northwestern part of Greenland.

One of those taking part, Professor Jason Box of Ohio State University, has been surprised by how little sea ice they encountered in the Nares Strait between Greenland and Canada.

He has also set up time lapse cameras to monitor the massive Petermann glacier. Huge new cracks have been observed and it's expected that a major part of it could break off imminently.

Professor Box said: "The science community has been surprised by how sensitive these large glaciers are to climate warming. First it was the glaciers in south Greenland and now as we move further north in Greenland we find retreat at major glaciers. It's like removing a cork from a bottle."

 
Bio fuels a saviour for the airline industry ?
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There is wide agreement that to mitigate climate change, global greenhouse gas emissions must be reduced to 50% of 2005 levels by 2050, with industrialised countries cutting their emissions by 80%.

In order to achieve this goal, large increases in both energy efficiency and renewable energy will be required. Biofuel alternatives to petroleum are getting much attention for both ground and air transportation.

Combustion of fuels made from biomass (plant matter) recycles carbon dioxide extracted during photosynthesis back to the atmosphere, making the fuels nearly "carbon-neutral" if only modest amounts of fossil fuel are used to produce them.

However, many biofuel options will be greatly constrained by resource scarcity and cost. Using food biomass, such as rape, corn or soybeans, creates food/fuel conflicts. Opening up land to compensate for the reduced food output leads to large greenhouse gas (GHG) emissions during land clearing and tilling that offset reductions achieved in subsequent cropping.

Oil-producing crops, such as jatropha and camelina, can be grown on non-agricultural land but factors such as land availability and rainfall limit how much can actually be produced. Approaches using algae are attracting interest but costs are very high, and - as for camelina and jatropha - half or more of the harvested biomass ends up in by-products. In selecting bio-based transport fuels, two criteria stand out.

First, technologies are needed that maximise liquid fuel production and carbon mitigation from scarce biomass supplies.

Second, bio-derived products must be fully compatible with petroleum fuels.

That's particularly true for aircraft applications, because of the international nature of the aviation industry and because petroleum fuels will be widely used for decades.

 The NetJets-sponsored research at Princeton University is seeking to identify technologies for displacing petroleum and reducing GHG emissions from transportation, both air and ground.

NetJets, the world's largest provider of corporate jet services, is seeking ways to reduce its carbon footprint substantially: its customers expect it, and the long-term future of its business depends on it. The analyses show that the most promising options involve borrowing technologies that are already used with coal, along with carbon capture and storage (CCS) technology that is being developed to enable continuing fossil fuel use under a carbon policy constraint.

Superclean "synfuels", otherwise known as synthetic fuels, can be made from coal via commercial processes that begin with gasification. But the GHG emission rate for production and use of these fuels is about double that of petroleum fuels.

However, about half of the carbon is released at the plant as a stream of undiluted CO2, so CCS can be pursued at relatively low cost, reducing emissions to about the level of petroleum fuels - a lot better, but not nearly good enough for a carbon-constrained world.

What if synfuels were made from biomass via gasification? One advantage is that all biomaterials (not just speciality crops) can be processed, which increases the effectiveness of using scarce biomass resources. As for some other biofuels, the overall process of making and burning the liquid fuels would be nearly "carbon neutral".

However, under a carbon policy it would often be worthwhile to include CCS, making the overall GHG emission rate strongly negative - thereby greatly enhancing the carbon mitigation potential of scarce biomass supplies. Such biofuels are not competitive with crude oil-derived products today but are likely to be very competitive at carbon prices that may be typical in 20 years' time.

An option that can be pursued now involves co-processing biomass with coal in similar gasification plants with CCS. Co-processing about 40% biomass and 60% coal provides liquid fuels with a net-zero GHG emissions rate.

Moreover, the amount of liquid fuel produced per unit of biomass is twice as much or more than most other biomass options. The analysis suggests that fuels from such systems will be competitive with crude oil-derived products, even with zero pricing on GHG emissions, when the crude oil price is $100 per barrel - a figure that is expected to be typical once the global economy recovers.

The technology is ready to be deployed now in plants that co-process about 10% biomass and inject the captured CO2 into mature oil fields to coax out more crude oil. The world's first synthetic fuel plant with CCS - the US Dakota Gasification Project that produces synthetic natural gas (not liquid fuels) from coal - has been capturing a million tonnes of CO2 annually since 2000 and transporting it 300km by pipeline into Canada, where it is used for enhanced oil recovery.

Careful monitoring has shown that after repeated re-injection, the CO2 ultimately remains stored underground. The research has identified a credible bio-based liquid fuel supply strategy for solving the carbon problem for transportation, even with limited biomass supplies and without abandoning crude oil. The key concepts are gasification-based liquid fuels and CCS for both biomass and coal.

Coal/biomass-to-liquids technologies would be deployed first in coal-rich countries, to be followed by biomass-to-liquids technologies in coal-poor but biomass-rich regions.

 
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