The big global warming story isn't Americans finally accepting an inconvenient truth. Al Gore makes a brilliant presentation, but the big story is the undeniable impact of a severe, early onset, global heating which only paid deniers now refuse to accept. The emerging science story is the risk of this severe impact creating positive feedback which could ratchet up temperatures higher and faster - maybe 10 degrees and more; within decades, not a century away. The forthcoming fourth IPCC report will focus upon 'dangerous global warming'.
Is it possible that the Amazon might die in a third or fourth year of unprecedented drought? Could Los Angeles, St.Louis and Atlanta become as hot as Baghdad in the not too distant future? Could the rapidly melting polar ice sheets raise sea levels so fast that New York, London, Singapore and every other coastal city will have to endure New Orleans style inundation? Collapsing ecosystems, migrating species and disease? A world without polar bears or tigers and maybe soon without people?
Climate change isn't something that will happen in the distant future and increasingly it doesn't look like a gentle warming to which we can adapt.
Newly clear land and sea in polar regions will absorb more heat from sunlight which would have been reflected by ice and new science on 'carbon bombs' strongly suggest that this positive feedback loop is already in operation. The Amazon is a huge carbon sink that unexpectedly could be freed to become greenhouse gas. Melting permafrost, especially in Siberia's yedoma, filling with new lakes, are releasing methane. Beetles and other parasites normally kept in check by very cold winters are killing vast areas of heat stressed temperate and boreal forests; forest fires will help release this carbon into the atmosphere too.
Greenhouse gases from our burning of fossil fuels trap more heat which in turn melts permafrost releasing vast amounts of methane which in turn trap more heat raising temperatures and setting off more carbon bombs - runaway global heating:
Within the next decade or two, Lovelock forecasts, Gaia will hike her thermostat by at least 10 degrees. Earth, he predicts, will be hotter than at any time since the Eocene Age 55 million years ago, when crocodiles swam in the Arctic Ocean.
"There's no realization of how quickly and irreversibly the planet is changing," Lovelock says. "Maybe 200 million people will migrate close to the Arctic and survive this. Even if we took extraordinary steps, it would take the world 1,000 years to recover."
The costs today and the range of potential dangers - including the risk of extinction - from global heating suggests that the biggest non-story is the complete lack of informed public debate and the woeful inadequacy of all proposed emission reduction planning. Kyoto, recent Kyoto-style reduction programs, caps and trading, alternative energy development - the use of oil and other fossil fuel use and their contributions of greenhouse gases continue their relentless rise uneffected. Critical decades have been wasted. The problem of path dependence and resulting policy paralysis isn't even a lesson yet learned by climate change experts.
A Draconian change of paths is now clearly necessary and yet impossible. While now accepting human caused global warming, the public still perceives the danger as a moderate increase in temperature requiring shallow, blue box and biking style change.
"Further global warming of 1 °C defines a critical threshold. Beyond that we will likely see changes that make Earth a different planet than the one we know." James Hansen
Earth is already as warm as at any time in the last 10,000 years, and is within 1 °C of being its hottest for a million years, says Hansen's team. Another decade of business-as-usual carbon emissions will probably make it too late to prevent the ecosystems of the north from triggering runaway climate change, the study concludes (Proceedings of the National Academy of Sciences, vol 103, p 14288).
James Lovelock Says This Time We've Pushed the Earth Too Far
By Michael Powell
Washington Post Staff Writer
Saturday, September 2, 2006; C01
ST. GILES-ON-THE-HEATH, England
Through a deep and tangled wood lies a glade so lovely and wet and lush as to call to mind a hobbit's sanctuary. A lichen-covered statue rises in a garden of native grasses, and a misting rain drips off a slate roof. At the yard's edge a plump muskrat waddles into the brush.
"Hello!"
A lean, white-haired gentleman in a blue wool sweater and khakis beckons you inside his whitewashed cottage. We sit beside a stone hearth as his wife, Sandy, an elegant blonde, sets out scones and tea. James Lovelock fixes his mind's eye on what's to come.
"It's going too fast," he says softly. "We will burn."
Why is that?
"Our global furnace is out of control. By 2020, 2025, you will be able to sail a sailboat to the North Pole. The Amazon will become a desert, and the forests of Siberia will burn and release more methane and plagues will return."
Sulfurous musings are not Lovelock's characteristic style; he's no Book of Revelation apocalyptic. In his 88th year, he remains one of the world's most inventive scientists, an Englishman of humor and erudition, with an oenophile's taste for delicious controversy. Four decades ago, his discovery that ozone-destroying chemicals were piling up in the atmosphere started the world's governments down a path toward repair. Not long after that, Lovelock proposed the theory known as Gaia, which holds that Earth acts like a living organism, a self-regulating system balanced to allow life to flourish.
Biologists dismissed this as heresy, running counter to Darwin's theory of evolution. Today one could reasonably argue that Gaia theory has transformed scientific understanding of the Earth.
Now Lovelock has turned his attention to global warming, writing "The Revenge of Gaia: Earth's Climate Crisis and the Fate of Humanity." Already a big seller in the United Kingdom, the book was released in the United States last month. (He will speak in Washington, at the Carnegie Institution, Friday at 7 p.m.) Lovelock's conclusion is straightforward.
To wit, we are poached.
He measured atmospheric gases and ocean temperatures, and examined forests tropical and arboreal (last year a forest the size of Italy burned in rapidly heating Siberia, releasing from the permafrost a vast sink of methane, which contributes to global warming). He found Gaia trapped in a vicious cycle of positive-feedback loops -- from air to water, everything is getting warmer at once. The nature of Earth's biosphere is that, under pressure from industrialization, it resists such heating, and then it resists some more.
Then, he says, it adjusts.
Within the next decade or two, Lovelock forecasts, Gaia will hike her thermostat by at least 10 degrees. Earth, he predicts, will be hotter than at any time since the Eocene Age 55 million years ago, when crocodiles swam in the Arctic Ocean.
"There's no realization of how quickly and irreversibly the planet is changing," Lovelock says. "Maybe 200 million people will migrate close to the Arctic and survive this. Even if we took extraordinary steps, it would take the world 1,000 years to recover."
Such dire talk no doubt occasions much rolling of eyes in polite circles, particularly among scientists in the United States, that last redoubt of global-warming skeptics. Lovelock's so intemperat e, and more than a few of his peers distrust his preference for elegant nouns and verbs served with no crusting of jargon. His grim predictions tend to be twinned in the press with those of the skeptics, each treated as a radical diversion -- purveyors of "climate porn," an English think-tank called them recently -- from a moderate mean.
Lovelock's radical view of global warming doesn't sit well with David Archer, a scientist at the University of Chicago and a frequent contributor to the Web site RealClimate, which accepts the reality of global warning.
"No one, not Lovelock or anyone else, has proposed a specific quantitative scenario for a climate-driven, blow the doors off, civilization ending catastrophe," writes Archer.
The headline on Archer's essay, which is in fact respectful of Lovelock's science, calls the Englishman a "renegade earth scientist." It's a curious description.
Lovelock works independently on various biochemistry projects, in a lab in an old barn behind his farmhouse in Devon. He often quarrels with the scientific establishment, which he sees as crippled by clubby orthodoxy. (Nor does he hesitate to tweak environmentalists -- Lovelock is a passionate backer of nuclear power as a carbon-clean palliative for global warming.) But it's difficult to see Lovelock, an inventor with 50 patents to his name, a fellow in the Royal Society -- England's scientific society -- as a Gaian bandito.
What's perhaps as intriguing are the top scientists who decline to dismiss Lovelock's warning. Lovelock may be an outlier, but he's not drifting far from shore. Sir David King, science adviser to Prime Minister Tony Blair, saluted Lovelock's book and proclaimed global warming a far more serious threat than terrorism. Sir Brian Heap, a Cambridge University biologist and past foreign secretary of the Royal Society, says Lovelock's views are tightly argued, if perhaps too gloomy.
Then you dial up Paul Ehrlich, the eminent Stanford University biologist, at his cottage in the mountains of Colorado, where he's been meeting with other scientists. Three decades ago Ehrlich wrote "The Population Bomb," a best-selling jeremiad in which he warned that the Earth's population was expanding much too fast.
Disaster did not arrive precisely as Ehrlich foretold, and he was treated as a doomsayer debunked. Maybe Ehrlich just was too early to the party.
Today Ehrlich sees global warming and population growth, with its attendant pressures on natural resources and demand for oil and gas, as menaces dancing in tango step. "Technically speaking, most scientists I know are scared [expletive]," Ehrlich says. "Lovelock and I are doomsayers because I'm afraid we see doom."
"Like the Norns in Wagner's Der Ring des Niebelungen, we are at the end of our tether, and the rope, whose weave defines our fate, is about to break."
You read such lines in "The Revenge of Gaia" and ask this wiry Jeremiah: Why so gloomy? Lovelock grins, his face a web of smile lines, and demurs: No, no, no. You have him all wrong. He started a family in the darkness of the London Blitz -- he has nine grandchildren, whom he loves, and a country of which he's very proud.
"I'm an optimist," he says. "I think that after the warming sets in and the survivors have settled in near the Arctic, they will find a way to adjust. It will be a tough life enlivened by excitement and fear."
That still sounds a tad short of good cheer.
Lovelock and Sandy, whom he married after the death of his first wife, take afternoon walks in Devonshire, and he quotes Shakespeare on the joy of finding oxlip by a stream. Lovelock finds too much delight in the mysteries of the universe to call himself an atheist. But he remains at heart a biochemist, a rigorous empiricist who refuses to shrink from the reality of hard times.
Lovelock grew up in working-class London. He could not afford Oxford or Cambridge and so attended at night. During World War II Lovelock walked sentry duty with professors on the roof of the lab. They watched the twinkling lights of German V-1 missiles draw close.
"A missile would veer off and explode and the professors would feel an immediate need to impart their wisdom." Lovelock chuckles. "It was like a graduate course. Terrible to say, but war makes us more alive."
Lovelock was a prodigy, earning degrees in chemistry and medicine. In the 1950s he designed an electron capture machine, which provided environmentalist Rachel Carson with the data to prove that pesticides infected everything from penguins to mother's milk. Later he took a detector on a ship to Antarctica and proved that man-made chemicals -- CFCs -- were burning a hole in the ozone.
"Gaia, shmaia," says Ehrlich, the Stanford biologist, who has been critical of Lovelock's latest theory. "If Lovelock hadn't discovered the erosion of the ozone, we'd all be living under the ocean in snorkels and fins to escape that poisonous sun."
In 1961 Lovelock worked with NASA. The space agency wanted to design a lander to search for life on Mars. That, Lovelock thought, was silly. What if a lander set down in the wrong spot? What if Martian life wasn't bacterial?
Lovelock took a conceptual leap. If Mars bore life, bacteria would be obliged to use oxygen to breathe and to deposit their wastes as methane. Lovelock found that Earth's atmosphere contained massive quantities of oxygen and methane, gases that are the very signature of life. Mars's atmosphere was thick with carbon dioxide, the calling card of a dead planet.
That discovery changed his life. He came to see Earth as a self-regulating biosphere. The sun has warmed by 25 percent since life appeared, so Earth produced more algae and forests to absorb carbon dioxide, ensuring roughly constant temperatures. In 1969, Lovelock lacked only a name for his theory. He took a walk with novelist William Golding.
A big concept needs a big name, Golding said. Call it Gaia.
Gaia proved controversial, and not just because the name made New Age priestesses go weak in the knees. ("Gaia's not 'alive' and I'm afraid I'm not a very good guru," Lovelock notes dryly.) Biologists nearly choked -- they argued that organisms cannot possibly act in concert, as that would imply foresight.
Lovelock recalls being denounced at a conference in Berlin.
The intolerance gave him a pain. Lovelock said that the world's biomass can act without being "conscious." "The neo-Darwinists are just like the very religious," Lovelock says. "They spend all their time defending silly doctrine."
Forty years later, talk of an interconnected planetary system is the lingua franca of Earth science. The queen has handed Lovelock a prize, Oxford has invited him to teach, and his small forest lab had more government contracts than he could handle. (In his lab, the octogenarian scientist follows few safety protocols save the dictates of self-preservation. "I can kill only myself; it's a splendid freedom," he says.)
But friends say he's restless.
"Maybe Jim thinks the world has gotten too comfortable with his theory," says Lee Kump, a prominent geologist at Penn State. "He sees Gaia treating us as a body does an infection -- it's trying to burn us out."
"The meltdown of Greenland's ice sheet is speeding up, satellite measurements show."
-- BBC, 2006
"Dr. Deborah Clark from the University of Missouri, one of the world's top forest ecologists, says the research shows that 'the lock has broken' on the Amazon ecosystem. She adds: T he Amazon is 'headed in a terrible direction.' "
-- CNN, 2006
How will our splendid Spaceship Earth so quickly become the oven of our doom? As we sit at his table in Devon, Lovelock expands on his vision.
It begins with the melting of ice and snow. As the Arctic grows bare -- the Greenland ice cap is shrinking far faster than had been expected -- dark ground emerges and absorbs heat. That melts more snow and softens peat bogs, which release methane. As oceans warm, algae are dying and so absorbing less heat-causing carbon dioxide.
To the south, drought already is drying out the great tropical forests of the Amazon. "The forests will melt away just like the snow," Lovelock says.
Even the northern forests, those dark cool beauties of pines and firs, suffer. They absorb heat and shelter bears, lynxes and wolves through harsh winters. But recent studies show the boreal forests are drying and dying and inducing more warming.
Casting 30, 40 years into the future, Lovelock sees sub-Saharan lands becoming uninhabitable. India runs out of water, Bangladesh drowns, China eyes a Siberian land grab, and local warlords fight bloody wars over water and energy.
Lovelock sees the look on your face and pauses.
"Look, this is why it's a gloomy book," he says. "Would you care for some more tea?"
The mind reels off objections. Doesn't this amount to a great piling up of what-ifs and could-bes? "The Day After Tomorrow," "On the Beach," Helen Caldicott, Nostradamus, a thousand tipping-point predictions of doom fade into the mists of human history. We humans are clever. We'll send a space shade into outer space to deflect sunlight (as a couple of California professors have proposed)?
Lovelock nods, weary; he's heard this before.
"We like to think of Hurricane Katrina, or a killer heat wave in Europe, as a one-off," he says. "Or we like to think that we'll come up with a technological fix."
Lovelock reminds you that the Mayan seers, to name another maligned bunch of doomsayers, were spot on. Their great civilization died of an environmental apocalypse. He's not romanced by the primitive. Across the world, from the American Indians to the aborigines of Australia to European hunters, research is suggesting that native peoples played a key role in the burning of forests and the extinction of thousands of species. Today the environmentally conscious seek salvation in solar cells, recycling and ten thousand wind turbines. "It won't matter a damn," Lovelock says. "They make the mistake of thinking we have decades. We don't."
Lovelock favors genetically modified crops, which require less water, and nuclear energy. Only the atom can produce enough electrical power to persuade industrialized nations to abandon burning fossil fuels. France draws 70 percent of its power from nuclear plants.
But what of Three Mile Island? Chernobyl? Lovelock's shaking his head before you complete the litany. How many people died, he asks. A few hundred? The radiation exclusion zone around Chernobyl is the lushest and most diverse zone of flora and fauna in Eurasia.
Sir Brian Heap accepts this. But he worries that South Asia and Africa are about to suffer the terrible consequences of First World excesses. What of our responsibility to them? "The poor aren't our problem," Heap says. "We're their problem."
Lovelock acknowledges the moral conundrum. But he sees no we-are-the-world solutions. The heat waves that kill millions, the powerful typhoons, the droughts that suffocate cities, will force a retreat to nationalism.
After a couple of hours, you wonder about his own good cheer. His internal combustion engine shows few signs of flagging; he wakes up 5:30 a.m. and reads, writes and tramps through the countryside. The studiously polite Lovelock seems a touch annoyed only at the suggestion he's frivolous about what the future holds.
"People say, 'Well, you're 87, you won't live to see this,' " he says. "I have children, I have grandchildren, I wish none of this. But it's our fate; we need to recognize it's another wartime. We desperately need a Moses to take us to the Arctic and preserve civilization.
"It's too late to turn back."
Executive summary
Climate change science has made important gains since the IPCC Third Assessment Report (TAR). The evidence for a warming Earth is stronger and the impacts of climate change are becoming observable in some cases. The broader climate-related research community is beginning to tackle one of the most fundamental and difficult questions associated with the climate change issue – what constitutes “dangerous” climate change? Article 2 of the United Nations Framework Convention on Climate Change states that emissions of greenhouse gases should be limited to levels that avoid dangerous climate change. Although ultimately it is society’s role to determine what is dangerous and what is not, science can provide critical knowledge to underpin the societal debate. Recent advances in two major areas of research – determining by how much climate will change due to greenhouse gas forcing and observing and analysing the impacts of climate change – have thrown new light on the question of dangerous climate change.
Model-based estimates of the degree of global waming by the end of this century, lie between 1.4 and 5.8oC. In part, the spread in the range of estimates is due to the uncertainty about the nature and strength of processes that could dampen or amplify the initial greenhouse gas forcing. Most of the emphasis up to now has been on feedbacks associated with water vapour and clouds. Over the past few years, however, research has yielded a better understanding of three additional effects that were recognised as being important in the IPCC TAR but for which little quantitative information was available at the time.
The first of these effects is based on the radiative properties of aerosols, small particles suspended in the atmosphere that generally scatter incoming solar radiation and thus cool the Earth’s surface, acting in opposition to greenhouse gases. Estimates of the magnitude of the aerosol cooling effect have now been made, and the estimates are moving towards a higher value than earlier thought. This implies enhanced warming later this century as greenhouse gas concentrations increase and aerosol loadings are reduced. A second effect is associated with a decrease in albedo – the reflectivity of the Earth’s surface – caused by the melting of snow and ice. The most dramatic example of this effect will likely occur in the Arctic Ocean, which is now projected to become almost totally ice-free in summer late this century. Retreating ice and snow expose darker underlying land and ocean surfaces, leading to enhanced absorption of sunlight and further warming.
Thirdly, terrestrial carbon cycle dynamics are expected to change significantly through this century, with strong amplifying feedbacks to climate change. Several processes – the oxidation of soil organic matter, the number and areal extent of major disturbances such as fire, and the stability of carbon pools in wetlands and frozen soil – are all sensitive to climate. As temperature rises, these processes in general release further amounts of carbon to the atmosphere, forming a feedback loop that intensifies the warming.
Although much uncertainty still surrounds the timing, rate and magnitude of these effects, they all operate to amplify the initial greenhouse warming. Thus, there is now perceived to be a greater risk that the upper end of the well known IPCC TAR estimate of a 1.4 to 5.8°C temperature rise will be reached or exceeded by 2100.
The impacts of a changing climate are beginning to emerge. High temperature extremes, such as the August 2003 heatwave in central Europe that had severe impacts on human health, are becoming more common. Although any individual event cannot be attributed unequivocally to climate change, the probability of such high temperature events increases with the underlying trend of rising mean temperature. According to data from the reinsurance industry, the number of climate-related disasters has increased since about 1970. Impacts of a warming world on the Earth’s biological diversity are becoming evident, especially in alpine ecosystems and in the northern high latitudes. The number of bleaching events on the world’s coral reefs has increased strongly over the last two decades, and the combination of increasing acidity in the ocean and higher sea surface temperatures, both highly likely to increase further over the next half-century at least, will put more pressure on reefs.
Less clear are the links between climate change and two phenomena that could lead to potentially devastating impacts – droughts and tropical cyclones. Some regions of the Earth have experienced 50-year drying trends, with circumstantial evidence linking the drying with increasing sea surface temperature. Although there is no evidence for an increase in the number of tropical cyclones, some studies show an increase in the destructiveness of tropical cyclones, again related to the increase in sea surface temperature.
The observational evidence which supports the fundamental principles of climate change science has grown even stronger in the post-TAR years. The atmospheric concentration of CO2 continues to increase, and several lines of evidence, most notably isotopic analysis, attribute most of this increase to the combustion of fossil fuels. The instrumental record showing a warming Earth is supported by satellite measurements of tropospheric warming and by observations in the cryosphere and biosphere. The heat content of the upper layers of the ocean is increasing. A growing number of reconstructions of surface temperature over the past 1000 to 2000 years shows that the sharp temperature rise over the past century is now beyond the bounds of natural variability.
The imprint of greenhouse gases as the primary cause of the observed warming has also become clearer. The pattern of heat uptake in the world’s ocean basins agrees well with that simulated by climate models for greenhouse gas forcing. The observed moistening of the upper troposphere accords with expectations for greenhouse gas-driven changes in atmospheric water vapour content.
In summary, post IPCC TAR research has confirmed with stronger evidence the patterns of climate change described in the TAR. In addition, research over the past five years has taken a more systems-oriented approach to climate change, exploring the processes and feedbacks that affect the projections of climate change through the 21st century. A better understanding of the severity and rate of climate change over the coming decades is crucial to assessing the potential impacts on societies and ecosystems, some of which are now observable.
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