7 Visions of Our Hot, Awful Future

It wasn't so long ago that some hope lingered around global warming--a dedicated international effort could still turn things around and prevent catastrophic change. But have we now crossed the threshold? Last year in A World Without Ice, Henry Pollack put it simply: "Change is underway and is certain to continue, because of inertia in both the climate system and the global industrial economy; it is impossible to simply pull the plug and stop these systems in their tracks." Global warming is going to happen, and perhaps disastrously so.

And the zeitgeist has turned towards resignation, if 2010's books--with their gloomy covers featuring melting ice and submerged skyscrapers--are any indication. We've assembled their predictions, so you know what to expect from our hot future.

Pacific islands left thirsty by La Niña

The Pacific island nations of Tuvalu and Tokelau have declared a state of emergency due to severe water shortages. In response, New Zealand has sent water and two desalination units, and Samoa has also sent water.

Both nations rely on rain for drinking water, but there has been little rainfall for the past four months, says Richard Gorkrun of the Tuvalu Meteorological Service in Funafuti, Tuvalu. "Some villages in Tokelau only have enough water until the end of this week," says Jo Suveinakama of the Tokelau government.

A weak La Niña is causing the drought by cooling the surface of the sea around Tuvalu, says Daniel Corbett of forecasters MetService in Wellington, New Zealand. The cool waters have forced a large band of cloud off course.

"Normally the band would be flirting with Tuvalu and producing afternoon showers over the islands," says Corbett. "But now it's too far south, so they have been bone dry."

The clouds are not expected to return until next year.

Groundwater greed driving sea level rises

SLOWLY and almost imperceptibly the seas are rising, swollen by melting ice and the expansion of seawater as it warms. But there's another source of water adding to the rise: humanity's habit of pumping water from underground aquifers to the surface. Most of this water ends up in the sea.

Not many scientists even consider the effects of groundwater on sea level, says Leonard Konikow of the United States Geological Survey in Reston, Virginia. Estimates were published as far back as 1994 (Nature, DOI: 10.1038/367054a0), but without good evidence to back them up, he says. The last report of the Intergovernmental Panel on Climate Change said that changes to groundwater reserves "cannot be estimated with much confidence".

Konikow measured how much water had ended up in the oceans by looking at changes in groundwater levels in 46 well-studied aquifers, which he then extrapolated to the rest of the world. He estimates that about 4500 cubic kilometres of water was extracted from aquifers between 1900 and 2008.

That amounts to 1.26 centimetres of the overall rise in sea levels of 17 cm in the same period (Geophysical Research Letters, DOI: 10.1029/2011gl048604).

That 1.26 cm may not seem like much, but groundwater depletion has accelerated massively since 1950, particularly in the past decade. Over 1300 cubic kilometres of the groundwater was extracted between 2000 and 2008, producing 0.36 cm of the total 2.79-cm rise in that time. "I was surprised that the depletion has accelerated so much," Konikow says.

It's not clear if the acceleration will continue. Konikow points out that some developed countries are cutting back on aquifer use and even trying to refill them when there is plenty of rainfall. "I would like to see that implemented more," he says.

"While there remain significant uncertainties, Konikow's estimate is probably the best there is for groundwater depletion," says John Church of CSIRO Marine and Atmospheric Research in Hobart, Tasmania, Australia.

Ice-age nettles may survive in dark Chinese caves

Walk into a cave in south-west China and you could be stepping back 30,000 years in time.

So says Alex Monro, a researcher in tropical plant diversity at the Natural History Museum, London, who thinks the caves could be a time capsule preserving rare nettles from the time of the last ice age.

Working with researchers from the Chinese Academy of Sciences, Monro has identified seven species of nettle that grow in isolated, dark corners of the karst landscapes of Guangxi and Yunnan provinces. Some species can survive in conditions in which just 0.02 per cent of sunlight penetrates the cave – that's less than reaches 100 metres deep into the oceans. "They grow at the backs of the main caverns in near-dark conditions," says Monro.

"Some of the specimens came from areas with very low light levels indeed, and one can easily interpret the site as being under full cave conditions," says Frank Howarth of the Hawaii Biological Survey in Honolulu, a speleologist who specialises in karst caves and their ecologies.

"There must be something quite special about their photosynthesis," says Monro, although the team has not yet investigated the photosynthetic mechanism. "They probably activate the photosynthetic process very quickly, which enables them to take advantage of very short bursts of light, and they might go for slightly different wavelengths," he says.

The nettle species seem to be unique to the remote caves and gorges, growing in isolated groups. One species, Elatostema retrorstrigulosum, is limited to only 10 adult plants, some growing in a grotto, hidden among stalagmites. The team have identified two of the species as "critically endangered" under the criteria of the International Union for Conservation of Nature; the rest are either "endangered" or "vulnerable".
Cold blast from the past

Nettles like these are not found in the surrounding tropical forest. To explain the discovery of these pockets of rare plants in an environment that is too tropical to support them, Monro suggests that the rare species could be "relicts of a vegetation from a previous cooler climate that resembled that of the caves".

Ancient cave paintings threatened by tourist plans

Prehistoric paintings in northern Spain could be irreparably damaged if plans to reopen the Altamira cave to tourists go ahead. Local officials want to reopen the cave to boost the local economy, but visitors could heat the caves and introduce microbes that destroy pigments.

The Altamira cave paintings were discovered in 1879 and are thought to be at least 14,000 years old. The paintings have attracted huge numbers of visitors – 175,000 in 1973, the busiest year on record. But the cave was closed to the public in 2002 after photosynthetic bacteria and fungi were found to be consuming pigments at alarming rates.

Plans to reopen the caves could restart the damaging processes. A team from the Spanish National Research Council in Madrid have modelled the effect of visitors over a number of years and say that tourists would increase the temperature, humidity and carbon-dioxide levels in the cave, creating conditions in which microbes would thrive.

In addition, visitors would bring with them organic matter in the form of skin flakes, clothing fibres and dust, which microbes can consume. Air turbulence created by moving people would spread bacterial and fungal spores to other, previously unaffected spaces.
Another Lascaux?

Although reopening the caves might boost the economy in the short term, says lead researcher Cesáreo Sáiz Jiménez, the damage would outweigh the benefit. "The paintings are a legacy from the past and their importance exceeds local culture."

The researchers say they want to prevent the scale of damage that occurred at the Lascaux cave in France, where mismanagement led to successive waves of pathogens attacking wall paintings there. For example, pesticides intended to destroy microorganisms became a source of nutrients for them instead.

Sáiz Jiménez and his colleagues conclude that only isolation from the outside world can prevent the same kind of damage at Altamira.

Why size matters in the plant world too

Over 60 years ago, evolutionary biologist Bernhard Rensch calculated that males are typically the larger sex in big-bodied species such as humans, whereas females outdo them in small-bodied species such as spiders. Now it turns out that many plants obey Rensch's rule too.

Most plants produce both male and female sex organs, but around 7 per cent are dioecious, meaning individuals are purely male or female. Kevin Burns and Patrick Kavanagh at Victoria University of Wellington in New Zealand measured the leaf and stem sizes of 297 plants from 38 dioecious plant species in herbarium collections of the National Museum of New Zealand and discovered that they follow the sex-size rule

Hot Zone—A Warming Planet's Rising Tide of Disaster

It was a hot, sticky day when patient zero arrived at a local hospital in Brownsville, Texas, in June 2005. Her body was racked with chills, she couldn’t stop vomiting, her blood pressure was perilously low, and she was passing blood in her urine. Clueless as to the cause, doctors pumped her up with fluids to treat dehydration, dosed her with antibiotics, and sent her home. But when blood tests and clinical evaluation were done with the help of the regional Texas Border Infectious Disease Surveillance project, a surprising culprit was unmasked: dengue hemorrhagic fever, a deadly viral disease usually regarded as a risk only in the tropics.

Long thought eradicated in the United States, dengue is roaring back. There had been prior cases of the disease’s milder cousin, classic dengue fever, in Brownsville, a bustling metropolis of about 140,000 people at the southernmost tip of Texas on the Gulf coast. But this was the first well-documented case of the more serious form of dengue infection, hemorrhagic fever, in a Texas resident infected in the continental United States. It is unlikely to be the last. From 1995 to 2005, some 10,000 cases were reported in the United States and the Texas-Mexico border region. The Centers for Disease Control and Prevention (CDC) believes that many cases are never counted, so these figures may be a vast underestimate.

A range of factors influence the spread of the dengue virus, but rising global temperatures may be the most important of all. Like many tropical diseases, dengue is spread by mosquito bites, and mosquitoes are exquisitely sensitive to climate. Frost kills both adults and larvae, which is why the disease hadn’t previously been able to get a foothold in the United States. With the advent of warmer winters, there is nothing holding the insects back. As a result, the two species of mosquito capable of transmitting dengue fever—Aedes aegypti and Aedes albopictus, also called the Asian tiger mosquito—have substantially expanded their habitat range since the middle of the 20th century

The Future History of the Arctic

Viewed through certain eyes, the diminishing ice cover at the top of the world is not a harbinger of destruction but an open door to commerce. The Northwest Passage is coming, at last. The Arctic is loaded with resources, and today as the ice recedes and open water stretches further, energy developers are licking their lips at the chance to get at all that hydrocarbon booty buried beneath frigid seas. The fight to come is: Who has the rights to what?

Writes Charles Emmerson: "If there is a scramble for the Arctic, it is a scramble in slow motion." That's because going after Arctic energy resources requires not just waiting for the waters to become passable, but also negotiating the fact that "different legal regimes apply to the land, the sea, and the seabed." It might be easiest to negotiate a new treaty to govern the newly open Arctic, but Emmerson doubts this will happen. If for no other reason, he writes, the pool of Arctic nations would be inviting other nations to join the deliberations if they did so. It looks like the future of the Arctic will be legal mess, but it will be a legal mess sorted out by Canada, the United States, Russia, Norway, and Denmark (owner of Greenland) while the rest of the world watches from the sidelines.

The Weather of the Future

Can the Big Apple, a city of islands (and DISCOVER's home), be spared from rising seas and fiercer storms? As we covered earlier this year, there's plenty to do to save New York from encroaching waters. Some architects see a circle of marshland around Manhattan to keep the waves at bay, bringing back mollusks to create natural reefs, or raising buildings off the ground to keep them from flooding. But none of this will be cheap. In Peter Ward's thought experiment that saw Miami's doom, "the fight for New York alone had necessitated cuts to national defense to the point that that United States had completely withdrawn from its foreign bases, defaulted on its Social Security obligations, and abandoned its short-lived national health care system."

In her book, Heidi Cullen explains that there are more mundane annoyances on the way. She quotes Columbia University energy expert Steve Hammer: "For New York, climate change means blackouts." Plain and simple, more extreme heat means more AC running non-stop, and the city's power system won't be able to keep up. The water supply will be stressed as less precipitation will fall as snow on the Catskills, meaning less meltwater to flow to the city's taps.

Climatopolis

We are an adaptive species. Unlike the birds and butterflies, Matthew Kahn writes, we humans can adapt to whatever new world comes our way. An optimist in a pessimistic group, he focuses the upside of a disaster. For one thing, the Rust Belt could receive an overdue makeover. Given the steady declines of Cleveland, Buffalo, and Detroit, it sounds like a joke today to imagine them vibrant again. However, Kahn points to the revitalizations of Boston and New York City after the dreadful 1970s. If global warming makes the Sun Belt too sunny and unlivable, perhaps what was old will become new again. Foresight, he says, will be the key. People who buy Detroit property today for next-to-nothing will look good if the city booms again. "Climate change will create big profit opportunities for insurance companies that are nimble enough to accurately price the real-time risk that policy owners (such as homeowners) face in different locations," he writes.

His oddly specific prediction: We're all going to eat dried fruit in the future. Kahn reasons that growers will want to hold inventory to deal with market fluctuations brought on by climate-related agricultural disasters, and dried fruit keeps.

How to Cool the Planet

Britain's Royal Society is celebrating its 350th anniversary this year, and even such an august scientific organization is no longer putting its stock in humanity's ability to curtail its CO2 emissions in time to prevent disaster. Last year the society complied a full report on plan B schemes--ways to tinker with the planet on a grand scale to save us from ourselves. Ideas to hack the Earth are now mainstream, as seen in the mass market books by Jeff Goodell and Eli Kintisch that hit the now-familiar plans: seeding the sea with iron to encourage the growth of carbon-sequestering plankton, seeding the clouds with aerosols to reflect away more sunlight, seeding space with giant mirrors to cut the amount of solar energy that reaches our little blue marble.

"The rising interest in geoengineering is driven less by mad scientists than by spineless politicians," Goodell writes. He, like the scientists at the Royal Society, would prefer that we address our carbon emissions proactively and many years down the road look back at the idea of sci-fi scale planet tampering as sheer madness. But, we probably won't. We, most likely, will wait until the last minute and then splurge to save ourselves. However, he writes, geoengineering isn't a quick fix. It buys us some time, but we'll still have to live with the world we've created.

Fracking Nation

Environmental ?concerns over a ?controversial mining method could put America's largest ?reservoirs of clean-burning natural ?gas beyond reach. Is there a better way ?to drill??

Tracy Bank was concerned. A geochemist, she makes her living studying how water interacts with rocks. And four years ago, when she arrived at the State University of New York at Buffalo, water was definitely interacting with rocks.

Buffalo is perched on the edge of the largest known reservoir of natural gas in America, a geologic formation known as the Marcellus Shale (pdf). The 95,000-square-mile slab, which lies under sizable portions of West Virginia, New York, Ohio, and Pennsylvania, could contain up to 500 trillion cubic feet of natural gas—enough to meet the nation’s natural gas needs for at least two years. Owing to this bounty, the areas above the shale are now in the grip of an unprecedented gas-drilling boom. The gas is extracted using a method called hydraulic fracturing, or fracking, a technique that involves pumping millions of gallons of water laced with ?chemicals deep underground to blast open the shale and release the gas trapped inside. The blasting is what got Bank worried.

Fracking has already drawn considerable scrutiny from environmental groups, unhappy homeowners, and teams of lawyers who blame the drilling method for polluting pristine rivers, turning bucolic farmlands into noisy industrial zones, and leaking enough methane to make ordinary tap water as flammable as lighter fluid. Bank is now bringing attention to yet another problem: radiation. Her research shows that high-pressure fluids striking the shale could dislodge naturally occurring radioactive compounds such as uranium and strontium, putting groundwater at risk of contamination.

Climate Science Wins a Round, But the Campaign Goes Poorly

In 2010 climate researchers struggled to move past the controversy that had rocked their community the year before. The accusation was incendiary: that scientists had grossly exaggerated the case for global warming by manipulating their data. The evidence was murky: more than 1,000 e-mails and documents exchanged by leading climate scientists, which had been hacked from their computers. But the verdict, as delivered by five separate investigations, was clear: The accused scientists were exonerated of any misconduct.

Three British investigations focused on the Climate Research Unit at the University of East Anglia, site of the stolen e-mails and a leading center for studying global warming. Meanwhile, two American panels examined the integrity of Michael Mann, a prominent climate researcher at Pennsylvania State University. All five groups concluded that none of the scientists had violated academic standards. “We find that their rigor and honesty as scientists are not in doubt,” declared a report headed by Sir Muir Russell, chair of one of the British investigations.

Lisa Graumlich, a University of Washington paleoecologist who served on another British group, led by Lord Ronald Oxburgh, looked into a broader charge: whether there was something “fundamentally broken” about the integrity of the Climate Research Unit. Such charges, she determined, were baseless. On the contrary, as the Ox­burgh panel’s final report (pdf) put it, the attacks leveled against the scientists “showed a rather selective and uncharitable approach to information made available by the CRU.” Michael Mann was more blunt. In an e-mail to me, he asserted that the people who attacked his work “don’t have the science on their side, and they surely know this. So smears and disinformation are all they have left.”

Ice falls to near record low

This mosaic of satellite images over the Arctic Ocean shows ice levels nearing a record low set in 2007. Acquired from the European Space Agency's radar satellite Envisat ASAR, the blue areas represent regions where ice accounts for more than 80 per cent of the sea surface. ASAR captured the high resolution images over the course of three days beginning 9 September. The satellite's radar penetrates the obscuring effects of the Arctic's frequent dark hours and thick cloud cover.

Sea ice levels have plummeted since 1979, when satellite records of conditions in the Arctic began. By the 1980s, minimum ice levels observed at the end of each summer summer had already fallen 50 per cent.

The past five years have seen the five lowest levels on record. According to the National Snow and Ice Data Center in Boulder, Colorado, this year's minimum ice extent is 4.33 million square kilometres, just 160,000 square kilometres above the 2007 level. However, a team of researchers at the University of Bremen in Germany have come up with a separate estimate using a microwave sensor on board NASA's Aqua satellite. They suggest sea ice extent may have shrunk beyond 2007's minimum extent to an all-time low.

Fukushima's radioactive sea contamination lingers

Levels of radiation in the sea off the Fukushima-Daiichi nuclear plant remain stubbornly high six months after the earthquake and tsunami struck Japan on 11 March.

After levels peaked at around 100,000 becquerels per cubic metre of seawater in early April, much of the radioactive iodine, caesium and plutonium from Fukushima was expected to rapidly disperse in the Pacific Ocean.

Instead, it seems that the levels remain high. That could be because contaminated water is still leaking into the sea from the nuclear plant, because currents are trapping the material that's already there, or both.

Ken Buesseler of Woods Hole Oceanographic Institution, Massachusetts, has told The New York Times that he has received samples of seawater taken in July from near the plant that contained 10,000 becquerels per cubic metre. The corresponding level last year, only months before the disaster, was just 1.5 becquerels, he says.

Simon Boxall, an oceanographer at the University of Southampton, UK, says that much of the radioactive material will still be sinking down to the seabed and being absorbed by marine life.

Arctic ozone hole breaks all records

In the first three months of this year, something unprecedented happened in the skies over the Arctic. A large hole appeared in the ozone layer, far bigger than any seen there before.

The Arctic ozone layer suffers a little damage every winter, but the effect is normally short-lived. "This is a clear step beyond that," says Neil Harris of the University of Cambridge. As the measurements came in, ozone researchers began to debate whether the loss could be compared to that seen over the Antarctic. "It's the first time we've even discussed that question," says Harris.

Between 18 and 20 kilometres up, over 80 per cent of the existing ozone was destroyed. "The loss in 2011 was twice that in the two previous record-setting Arctic winters, 1996 and 2005," says Nathaniel Livesey of the Jet Propulsion Laboratory in Pasadena, California.

The hole was similar in size to those seen in Antarctica in the 1980s. The Antarctic hole has continued to grow since then, and is far larger today.

The Arctic ozone hole will have allowed more ultraviolet radiation than before through, but it is unlikely anyone has been seriously harmed, says Bruce Armstrong of the University of Sydney, Australia. "Occasional ozone depletion episodes such as this would add very little to the underlying population's risk of UV-related cancer."
Ozone killer

The question now vexing atmospheric scientists is why the hole grew so large, and whether it will open again. Livesey and his colleague Michelle Santee say the hole formed because the stratosphere remained cold for several months longer than usual. The cold air allowed water vapour and nitric acid to condense into polar stratospheric clouds, which catalyse the conversion of chlorine into chemically active forms that destroy ozone.

But we don't know why the stratosphere stayed cold for so long.

Air pollution is stunting India's monsoon

India has been drying out for half a century, and air pollution thousands of kilometres away is partly to blame.

The monsoon has been weakening since the 1950s. Indian air pollution has been blamed, but now it seems that emissions further afield are also a factor.

"The summer monsoon provides up to 80 per cent of total annual rainfall in south Asia, and supports 20 per cent of the world's population," says Yi Ming of Princeton University in New Jersey. With his colleagues, Ming used climate models to assess how different factors changed the monsoon.

The monsoon is brought by large-scale wind patterns that transport heat between the northern and southern hemispheres. For half the year the northern hemisphere experiences more solar heating and so is warmer than the southern hemisphere; the situation is reversed during the other six months. As the winds head north over the Indian Ocean during the northern hemisphere's summer they pick up moisture, which falls as rain over south Asia.

Air pollution in the form of aerosols can weaken these long-distance wind patterns, however. That's because it reflects sunlight back into space, cooling the polluted area. Thick aerosol pollution over Europe in summer ensures that the northern hemisphere isn't much warmer than the southern hemisphere, so there is nothing to drive the winds – and nothing to trigger the monsoon.

Lurching rains

Ming says his modelling suggests that the effect of European aerosol pollution accounts for about half the drop in the volume of monsoon rainfall – the other half is down to pollution over south Asia. In as-yet-unpublished experiments, he confirmed the important role that the European pollution plays in weakening the monsoon. He ran his models again, this time assuming no aerosol pollution over south Asia. Even so, India had a significantly weaker monsoon.

The study supports existing evidence that air pollution is weakening the monsoon, says Veerabhadran Ramanathan of the University of California, San Diego.

Another form of pollution – greenhouse gas emissions – is pushing the monsoon in the other direction, towards greater rainfall, says Ramanathan. The competing forces of the greenhouse effect and air pollution may lead to a much more variable monsoon, with drought one year followed by floods the next. He says this erratic behaviour is "more worrisome" than the overall decrease in rainfall.

Engineers can build a low-carbon world if we let them

The engineering solutions to combat climate change already exist. Politicians must be brave enough to use them before it's too late

One word sums up the attitude of engineers towards climate change: frustration. Political inertia following the high-profile failure of 2009's Copenhagen climate conference has coupled with a chorus of criticism from a vocal minority of climate-change sceptics. Add the current economic challenges and the picture looks bleak. Our planet is warming and we are doing woefully little to prevent it getting worse.

Engineers know there is so much more that we could do. While the world's politicians have been locked in predominantly fruitless talks, engineers have been developing the technologies we need to bring down emissions and help create a more stable future.

Wind, wave and solar power, zero-emissions transport, low-carbon buildings and energy-efficiency technologies have all been shown feasible. To be rolled out on a global scale, they are just waiting for the political will. Various models, such as the European Climate Foundation's Roadmap 2050, show that implementing these existing technologies would bring about an 85 per cent drop in carbon emissions by 2050. The idea that we need silver-bullet technologies to be developed before the green technology revolution can happen is a myth. The revolution is waiting to begin.
Climate call

The barriers preventing the creation of a low-carbon society are not technological but political and financial. That's why at a landmark London conference convened by the UK's Institution of Mechanical Engineers, 11 national engineering institutions representing 1.2 million engineers from across the globe, under the banner of the Future Climate project, made a joint call for action at December's COP17 climate change conference in Durban, South Africa.

The statement calls on governments to move from warm words to solid actions. They need to introduce legislation and financial support to get these technologies out of the workshop and into our homes and businesses and onto our roads. Targeted regulation and taxation will also drive innovation. This will require bold politics, and spending at a time when money is scarce. It is far from unaffordable, however. The UK's Committee on Climate Change, which advises the British government, continues to support the view of the Stern reportMovie Camera – an assessment of the climate change challenge in the UK – that the move to a low-carbon society will cost no more than 1 per cent of GDP by 2050.

Resistance to wind turbines and the power lines they feed, nuclear power and electric cars, as well as the economic costs, all make public opinion a powerful brake on change. However the alternative seems certain to be worse. It is not only the challenges of a deteriorating climate: with inaction comes a great risk to our economy in the long term. The green technology revolution, just like the industrial revolution before it, will give jobs to those countries which have created the right conditions for it to flourish.

Nuclear elephant

nvestment in renewable energy is vital for a prosperous, low-carbon society. However, decision-makers cannot ignore the elephant in the room – nuclear power. The enormous cost of implementing 100 per cent renewable power is not realistic for most nations, so nuclear offers our best chance of making a low-carbon society achievable and affordable. Yet the incident at Fukushima earlier this year has reinforced some long-standing concerns.

Unlike road use or smoking, nuclear power stirs anxieties in many of us that are out of proportion with its true risks. This is not to be complacent about the potential danger of a nuclear plant, but it is striking that nuclear power has killed fewer than 5000 people in its entire history. Compare that with coal mining, which in just one year and in one country – China in 2006 – killed 4700.