Monday, August 13, 2012

Population Surge: "10 Billion" - Stephen Emmott speaking at The Royal Court Theatre in London.

There has been a highly successful run at the Royal Court Theatre, in London, not of a play in the usual form, but of a lecture by Professor Stephen Emmott, who leads Microsoft's Computational Science Laboratory in Cambridge and is Professor of Computational Science at Oxford University. The title, "10 Billion" refers to the human population which it is thought may rise to this number by the end of the present century, with back-breaking pressure on the available resources of the Earth: principally those of food, freshwater, and energy. I attended its final performance last Saturday.

Since the inevitable outcome of consumption is excretion, by that time, we will be drowning in our own waste, particularly carbon, such that many lands including Bangladesh will be inundated. The global temperature rise, too, is thought not to be a mere 2 degrees C by the end of the century but 6 degrees, making life on earth, as Emmott describes it "a living hell."

Emmott describes himself as a "rational pessimist" and while his delivery is tinged with ironic humour, it is mostly deadpan, rendering the sheer facts and figures both compelling and convincing. I was at one time skeptical about global warming and its consequences, but now there seems to me little room for doubt that humanity is in a severe predicament, both from the aspect of resource depletion and treating the planet like a giant landfill tip.

Emmott points out that we are using all of the arable land available to us, as a population of 7 billion, and that to feed 10 billion will require clearing forested land, including rainforests which have been described as the "lungs of the earth".

Of all resources, that most critically threatened is water, and it is staggering the quantities of "hidden water" that are used to provide some very commonplace items. For example, it takes 3,000 litres of water to produce a beefburger, and in Britain some 10 billion burgers are consumed per year, therefore necessitating the consumption of 30 trillion litres, or 30 cubic kilometers (km^3) of water.

It takes 27,000 litres of water to produce one bar of chocolate.

100 litres of water are used to make one cup of coffee.

It takes 4 litres of water to make one one litre plastic bottle of water... that's before the water is put into it.

At a population of 7 billion, our energy consumption amounts to around 16 TW, and this will need to rise to 20 TW to provide for the eponymous "10 billion". Since we are highly dependent on fossil fuels, oil, gas and coal, which provide around 87% of the total energy used by humans on earth, our greenhouse gas emissions will almost certainly have to rise, given the limitations of renewable energy sources.

30% of greenhouse gas emissions originate from food production, which is more than from transportation or manufacturing.

To meet that 20 TW of energy, while avoiding burning carbon at an accelerated rate. would require building 960 new hydroelectric dams, each the size of the Three Gorges Dam which spans the Yangtze River in China, PLUS 15,000 NEW nuclear power plants. In terms of uranium fuel resources alone this does not seem very realistic, let alone making sufficient concrete (a hugely CO2 emitting process) for both dams and NPPs.

It is expected that demand for food will double by 2050. This not only reflects the rise in population per se, but that more affluent people eat more food, and the consumer society is expected to expand within that number.

Emmott gave two choices: to "technologise" our way out of trouble, but concluded this was unlikely to be possible and the other option was to "change our behaviour", by consuming less food, less water, and less "stuff". Surplus cash for "stuff" arose when food became cheap in consequence of the Green Revolution. Food prices are rising significantly, and the current US drought could have a drastic effect on world grain availability, with consequences across the world. A drought in Russia recently meant that some 40% of an expected 100 million tonnes of wheat was not produced. Russia held onto supplies to feed its own people which led to food shortages and riots in the far east, India and Pakistan. Emmott speculates, "imagine if that same proportion of the 400 million tonne US wheat output was lost"... indeed, the outcome would be catastrophic.

He is less than sanguine that humans will change their behaviour, believing that developing nations will still aspire to a western lifestyle, whereas the reality is that in the west we need to consume less while more than one billion people in the non-legacy nations, who are malnourished, need to consume more. And the outcome of this? As he puts it, "We're fucked", and I suspect he may well be right.

Apparently, species on Earth are becoming extinct at a rate one thousand times faster than the normal evolutionary rate as we consume the planet's resources.

In 1960, there were 100 billion air-miles flown. In 1980 this had risen to 1,000 billion air-miles and now it is 6,000 billion.

Emmott draws the analogy that if it were known that an asteroid was on its way and would hit the Earth in the year 2094, say, Astronomy and Physics being "simple subjects" would allow a precise prediction of the date and moment of impact and where exactly on Earth it would strike. He says that in such a case, the entire world would mobilise its resources, (1) to mitigate the damage and loss of life from the impact itself, and (2) to inaugurate the most effective procedures for how to cope in its aftermath. Although the likely number of casualties may well be of the same order, the threat to humans is not an external source, like an asteroid, but it is ourselves and our behaviour and yet we do nothing.

What however is the likelihood that the world human population will rise to 10 billion. According to UN's 2010 revision of its population projections, it will peak at 10.1bn in 2100. Some experts dispute the UN's forecast and have argued that birthrates will fall below replacement rate in the 2020s. According to these forecasters, population growth will be only sustained till the 2040s by rising longevity but will peak below 9bn by 2050.

That noted, a worst case scenario predicts that the world population will peak at 7.1 billion in 2024, and then fall to 2.5 billion (close to the estimated carrying capacity of the planet) by 2100. The latter assumes nothing and is a simple mathematical curve-fit of a logistic (population growth) function to actual population data. Is this a mathematical artefact or a simple reflection of a population with limited resources, like the behaviour of bacteria growing on nutrient agar in a Petri dish? Only time will tell, but the "10 Billion" problem may never arise, let alone 16 billion by the end of the century. We are an overshoot species, and may expect a rapid cull, as in the S-shaped curve that prevails for bacteria. The initial growth is slow, but then given sufficient resources (food - oil, and gas in the human situation), the population rapidly escalates until it can no longer be sustained by its food. Then the bacteria begin to starve and consume each other.

Saturday, August 11, 2012

Terminal Shortage of Water for U.S. Agriculture.

Cheap light crude oil production has already peaked and the resource will be all but gone within a decade. It is a matter of ebullient debate exactly to what extent that gap might be filled by unconventional sources of hydrocarbons, e.g. from tar-sands, ultra-heavy oil, oil shale, shale oil (they are not the same thing) and fracking in general. This spectral shadow looms, of the intermediary era that straddles then from now - dearth from plenty - a highly uncertain transitional period within which, either by design or default, we must gear-down our use of transportation, since there is no alternative technology that could be brought on-stream in time (if ever) to match the gargantuan 30 billion barrels of oil that are used by the world each year to quench its thirst for liquid fuel and essential chemical raw materials for industry.

Water too, is a resource that given its careless usage will begin to run-short within a few decades, as is espoused in the book entitled "Mirage", written by Cynthia Barnett, which focusses on water-use in the United States and in Florida particularly. Years ago I read "The Grapes of Wrath" by John Steinbeck which draws-out in painful detail the tribulations of families trying to survive in the dust-bowls of the mid-west during the Great Depression era of the 1930's, struggling toward California in a search for jobs and land, but mostly land... on which crops would grow. It is well known that to the east of the longitudinal line along the 100th meridian rainfall is plentiful, while to the west of it the climate is relatively arid. Indeed it was once believed that farmers in the "east" would never have to worry about watering their crops, but in recent years demand for water has surged with calamitous environmental consequences.

Barnett is an experienced journalist and a reporter for Florida Trend Magazine, and her investigative and journalistic skills are aptly suited to handle this important topic. In the first part of the book, she outlines the history of water and development in the US reflecting back from an opening scene from 1981 where a house falls into a "sinkhole", which is a collapse in the limestone rock that underlies Florida as a consequence of its natural dissolution by underground water, but which can be opened-up as a result of human activities such as highway construction, excavation of "fill-dirt" (gravel), well -drilling and especially the excessive pumping of groundwater.

She discusses the complex politics involved in "development", and the overpopulation of that southern tip of the Florida peninsular particularly by retirees ("seniors"), thus requiring an infrastructure - including very green and hence heavily watered lawns and golf-courses etc. - of an extent that surpasses even what can be provided by the greatly abundant rainfall there. Meeting the shortfall necessitates the extraction of groundwater on a huge scale with environmental, economic, political and social consequences, including at least one death as she describes in the chapter "Water Wars". Indeed the history of water-supply in the United States is wryly inscribed in the quotation (attributed to Mark Twain), "whiskey's for drinkin' and water's for fightin'."

A central theme in the book is of water as a commodity. Often the real costs of water provision are borne by states or municipalities rather than by corporations, who cash-in on a cheap resource for which no regard is consequently engendered, nor for the environmental actions such as damming rivers as mighty as the Colorado for various "aquatic" projects. Bottled "spring" water is an immensely priced-up designer toy, costing around 10,000 times as much as tap water and often with much the same analytical composition. Not all spring-water does in fact come from a spring, and is to a large degree once again that good old pumped groundwater.

The Ogallala aquifer flows for 174,000 square miles under the great plains from South Dakota to the Texas panhandle, and it is the main source of water for the US collective national breadbasket, supplying as it does one third of all the groundwater used for irrigation in the entire country. However, Ogallala is not replenished as most aquifers are. Instead it contains "fossil water", set down from the melt of the last ice-age 10,000 years ago. Put another way, once it is gone it is gone, and the analogy with a vast oil-field could hardly be closer. Access to cheap electric pumps in the 1950's permitted farmers to draw this legacy upward at increasing rates and to the extent that the Ogallala has fallen by 100 feet in parts of New Mexico, Kansas, Oklahoma ("Grapes of Wrath" territory) and Texas. It is inevitable and a mere matter of time that all wells sunk into this huge aquifer will run dry. Not good I presume for the US corn-crop which is increasingly being grown to provide corn-ethanol in that desperate exercise we are all of us involved in, to resolve the issues of how we will survive in the "Oil Dearth" era, as world supplies of crude-oil run relentlessly short.

The Aquifer Storage and Recovery (ASR) technology is given especial mention. The idea is that during wet-periods, when water is plentiful, water is pumped into gigantic underground aquifers set deep into Florida's limestone, and which can be pumped-up again during dry months. Some 36 million gallons a day are sucked from Peace River, which starts in Central Florida's Green Swamp and ends 105 miles further south in the Charlotte Harbour Estuary. There are almost 1,700 ASR wells in the US altogether, most of them in the states of California, Nevada, Texas and Florida, all particularly short of water. However, caution is urged, certainly that a decent hydrogeological survey is forked-out for, as the first well sunk at Peace River became seriously contaminated with arsenic, present naturally in the aquifer.

Desalination is another technology often invoked as a solution to water-shortages especially in near-coastal regions, even though it is very costly to set up a desalination plant in the first place, and it takes a lot of energy to run one; nor is the technology guaranteed. A $110 million plant at Tampa Bay suffered all kinds of difficulties and finally the high-tech membranes required to separate water from salt by reverse-osmosis clogged up. However, groundwater pumping was reduced by one third in the region anyway without using one drop of desalinated water, purely through more conventional means of reservoir and surface water treatment combined with aggressive water-conservation measures. Now this takes us on neatly to the final chapter entitled "redemption and the river of grass".

I found this chapter truly inspirational, since it refers to possible solutions to the problem which are based around taking a more respectful approach to our environment. Some wonderful human stories are mentioned, such as that of Clyde Butcher, who turned his son's tragic death into a positive campaign for the choking Everglades, through his photography, and began a change in attitude which may save the day. What Barnett writes about water and how we might preserve our world by giving it due respect applies as well to all the other resources we are now plundering into extinction.

As a published poet, I appreciated her choice of Samuel Taylor Coleridge's "Kubla Khan" to quote from rather than "The rime of the ancient mariner" as it usually done when seeking some cultural reference to "water", since the context is much closer in its "A stately pleasure-dome decree" to the problem of inexorable human demand on nature in the fallacious assumption of limitless growth while draining resources that are only all too limited. In conclusion, this is a most informative and timely book and I am grateful to Mary Bisbee-Beck at The University of Michigan Press for giving me the opportunity to review it.

Professor Chris Rhodes, Independent Consultant on Energy and Environment Issues.