Regional Impacts of Climate Change: Four Case Studies in the United States
Prepared for the Pew Center on Global Climate Change
December 2007
By:
Kristie L. Ebi, ESS
Gerald A. Meehl, National Center for Atmospheric Research
Dominique Bachelet, et al., Oregon State University
Robert R. Twilley, Louisiana State University
Donald F. Boesch, et al., University of Maryland Center for Environmental Science
Download full report (pdf) or individual case studies:
[This post originally appeared on the Center for Global Development’s “Views from the Center” blog.]
The White House finally blinked in the final hours of the UN’s Bali Conference on Climate Change. The catalyst may have been the unprecedented boos and hisses directed at the US delegation from the floor, or the peremptory challenge from Kevin Conrad, Papua New Guinea’s representative: “If for some reason you are not willing to lead, leave it to the rest of us. Please, get out of the way.” Confronted by the prospect of pariah status, the US dropped its categorical resistance to emissions reduction targets and permitted their inclusion in a footnote to the final agreement. This was a belated recognition of an obvious truth: We will not keep emissions within safe limits without some form of mandatory carbon regulation.
Less-appreciated, perhaps, is the fact that China, India and other developing nations also blinked. For the first time, they accepted the principle that verified reduction of their emissions should be considered in a future agreement. From a global perspective, this was a victory for common sense. As Kevin Ummel and I note in a recent paper, unrestricted emissions from developing countries are growing so rapidly that they will create a climate crisis in this generation, even if developed-country emissions fall to zero immediately.
And the Europeans blinked as well, although their rhetoric remained aggressive to the end. After insisting on quantitative targets throughout the conference, they grudgingly accepted a non-specific commitment to future emissions reductions, and abandoned their threat to boycott US-sponsored talks among major carbon emitters. This was simply realistic, because the deal that must be struck will include many more elements than emissions targets.
Everyone ultimately blinked on Bali because they recognized several uncomfortable truths: The global stakes are mortal; time is short; success depends on universal participation; and getting everyone onboard will be impossible if negotiations focus only on emissions reduction targets. A sustainable global compact to halt global warming will also require provisions for clean technology development, accelerating global adoption of clean technology; and assisting poor countries that will be hard-hit by inevitable climate change.
Negotiating the global compact will not be simple, because each country faces different opportunities, risks and costs (For a comprehensive look, see “Country stakes in climate change negotiations : two dimensions of vulnerability“). To cite a few examples among many: Some countries (most notably the US and China) are so dependent on coal-fired power that a very rapid transition to clean energy will be wrenching and costly. They will not join a compact that threatens their economic and political stability. Many developing countries have huge renewable-energy potential, but it can only be tapped with developed-country support. This should include relaxing intellectual property laws to permit low-cost deployment of innovative technologies, but too much relaxation will eliminate the profit incentive that drives innovation in the first place. And for developed countries, the cost of supporting clean technology development will have to be weighed against their own transition costs, as well as the costs of assisting developing countries with adaptation to climate change.
Everyone blinked at the Bali Conference, opening the way for serious work on the global compact. The North and South are now fully aware of their interdependency. Each side emits enough carbon to create a climate catastrophe, and each faces such heavy transition costs that accepting them will require a new vision of global development. The North has the financial and scientific resources to support the compact, but carbon mitigation by the South is the key to making it work in the long run. The compact will have to reflect a host of country-specific benefits and costs associated with emissions reduction, accelerating the transition to clean technology, and financing adaptation to climate change.
While many uncertainties remain, one thing is certain: In forging the compact, this generation will shoulder a huge cost to protect future generations. And the sacrifice will only be acceptable if the global compact respects strict principles of accountability and transparency. To forge a meaningful compact, the international community has to know where carbon emissions are coming from; who is accountable for them; and what concrete steps are being taken to reduce emissions.
The demand for accountability and transparency defines an action plan that we can start implementing now. To establish accountability, the UN should immediately develop a global inventory of emissions from all critical sources, including deforestation. This inventory should identify specific sources (e.g. power plants, cement mills, motor vehicle fleets, land-clearing operations), and the organizations that are accountable for them. To ensure transparency, the emissions inventory should be disclosed to the global community on an accessible, easy-to-use, constantly-updated website.
At the Center for Global Development, we have attempted to catalyze this international effort by launching CARMA (Carbon Monitoring for Action) at www.carma.org. CARMA is the first global carbon disclosure site for the power sector, which produces over 25% of all carbon emissions. It provides easily-accessible emissions and power data for 50,000+ power plants, 20,000+ power companies, and 200,000 locales. With very limited resources, we have established an initial benchmark for global accountability and transparency. Now we believe that the international community should step up. The United Nations, or a consortium of donor nations, should immediately apply the same principles to building a comprehensive public emissions inventory that will provide a key foundation for negotiating the global compact. It’s the first step on a long road, and time is short. Let’s get started.
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Taking Responsibility: Why the United States Must Lead the World in Reducing Global Warming PollutionMany individual states release more greenhouse gas (GHG) emissions than entire groups of developing countries. Forty-two U.S. states individually emit more carbon dioxide than 50 developing countries combined, and three states individually emit more CO2 than 100 developing countries. “Taking Responsibility,” a new report by the National Environmental Trust, examines the greenhouse gas emissions of U.S. states as compared to developing countries and underscores the moral necessity for the United States to assume global leadership in ongoing efforts to craft a new post-Kyoto global climate treaty. Featuring a state by state profile of GHG emissions, the report also examines individual and collective efforts by U.S. states to reduce GHG emissions. Find out more:
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| Paper/plastic: Sara Stinchcomb carries groceries to her car in Annapolis, Md. The town had proposed a ban on plastic bags; it failed. Kathleen Lange/AP |
from the December 19, 2007 edition
Paper, plastic ... or biodegradable? Yes, get ready to add a third option at the grocery store checkout line as biodegradable plastics enter the mainstream consumer market.
It is hard to imagine that the plastic grocery bag made its debut only 30 years ago. But now, even in Antarctica, scientists regularly find them blowing about.
The problem is that, unlike many other overnight sensations, plastics stick around. It can take roughly 1,000 years for some petroleum-based plastics to disintegrate. And when they do disintegrate, traditional plastics leave behind a messy legacy of fragments and chemical residues that get absorbed into streams and soil. In the meantime, they clog landfills and rivers, or kill whales and sea turtles that mistake them for food. With up to 1 trillion plastic bags manufactured annually and 2.7 million tons of plastic used just to bottle water each year, concern is rising worldwide.
Enter bioplastics, designed to degrade into an ecofriendly mix of water, carbon dioxide, and biomass. While biodegradable plastics have been introduced before in the past 20 years, they have failed to achieve widespread use due to their inferior strength and higher cost. But this is changing, says Steve Mojo, executive director of the Biodegradable Products Institute (BPI) in New York City.
"In the last decade, we've seen that through improved production technology … these materials have become comparatively durable and affordable, without leaving behind the remnants that petroplastics do," says Mr. Mojo.
While the cost of producing bioplastics ranges from as little as 10 percent more to many times that of traditional plastics, bioplastics companies have seen an increased demand due to rising environmental concerns among consumers and changing environmental regulations. The improved strength, meanwhile, is great news to any trash collector or conscientious pet owner who knows the hazards of an inferior plastic bag.
But when it comes to disposal, not all bioplastics are created equal, leading to confusion for consumers and waste-management groups alike. Bioplastics are not uniform in their ability to decompose under different conditions. While some brands can biodegrade within a few months in backyard compost piles, others require several months at industrial composting facilities.
NatureWorks, the largest producer of bioplastics (they make about 300 million pounds per year), distributes beverage bottles made from polylactic acid (PLA), a hydrobiodegradable polymer. Its bottles are touted as biodegradable within 100 days – but only if it reaches an industrial composting plant with high humidity and temperatures.
According to the Container Recycling Institute, such bottles are unlikely to end up at such plants; of the estimated 25 billion single-serving, plastic water bottles Americans will buy this year, 8 out of 10 (22 billion) end up in landfills. Many stores do not accept returned PLA plastic for recycling or composting. And given that scarcely more than 100 industrial composting facilities exist nationwide, some question the benefits of bioplastics largely destined to end up as litter or in dumps.
In contrast to NatureWorks, Mirel, a product line of Metabolix Inc., says its products – including bags, gift cards, and razor-blade handles – will decompose in a backyard composter within two months, and within four months in soil, fresh water, or salt water.
Currently, both companies' products are primarily made of modified corn feedstock, as opposed to petroleum byproducts. Ultimately, the natural polymers biodegrade as microorganisms consume them. While this source of plastic seems earth friendly, some environmentalists say the footprint of corn cultivation should be considered.
"Corn, overall, is very energy intensive, requiring a considerable amount of fertilizer and gasoline to produce and transport each bushel," says Janet Larsen, research director of the Earth Policy Institute in Washington. "The nitrogen-rich fertilizer then often becomes runoff in streams, rivers, and oceans, creating algal blooms that kill marine life."
Using feedstock for plastic further exacerbates record high corn prices, says Ms. Larsen, adding that corn supplies are already stretched thin by demands for food and ethanol. "This should make society ask, 'Do we really want to be turning food into plastic?' "
The definition of bioplastics has been further clouded by Symphony Environmental, a British bioplastics company that claims to have developed a petroleum-based plastic that biodegrades into a benign mix of water, CO2, and biomass. By adding a small amount of degradant in the manufacturing process, the plastic begins the decomposition process after a preset time that varies from product to product. Because no fragments of petropolymers remain, these products can safely be composted, says the manufacturer.
"There is a widespread confusion that all [bioplastics] are made from renewable resources and that all of them are biodegradable," says BPI's Mojo. "Not all plastics made from renewable resources are biodegradable, and not all that are biodegradable are based on natural resources."
Mojo, who works closely with the American Society for Testing and Materials International to develop specifications for products that biodegrade in various environments, says that "the industry is in its infancy" and work is being done to develop more uniformity in composting and recyclability. "We will see more bioplastics in the next five to 10 years as technology advances, and we will see visible improvements in strength, cost, and degradability," he adds.
In the meantime, Larsen of the Earth Policy Institute suggests the environmentally conscious choose a fourth option at the checkout line: "We would do better to bring our own canvas bags shopping or buy reusable water bottles and move away from the throwaway mentality that one-time use products afford us."
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This image of part of the Mingyong glacier was taken in 1913. Courtesy Royal Geographical Society
An image taken in 2004 from the same point, below a Tibetan Buddhist temple, shows the glacier's retreat. Courtsey The Nature Conservancy
The scientists have noted more crevasses and wastage in the body of the glacier, which they say is making it more unstable. A local meteorologist estimates that it has shrunk by one-quarter in 13 years, but the glacier is considered sacred, so normal scientific practices, such as removing ice cores, are not permitted. Courtesy The Nature Conservancy
The glacial melt runs off the ice mass. The four rivers that begin the Northwest Yunnan are mostly glacier-fed in their upper reaches. Courtesy The Nature Conservancy
Morning Edition, December 17, 2007 · The Tibetan plateau has been called "the roof of the world" and "the third pole" for its ice-covered peaks. There, global warming is happening faster than at other, lower altitudes, with serious consequences for hundreds of millions of people.
China's lowest glacier, the Mingyong glacier — an enormous, dirty, craggy mass of ice wedged in a mountain valley 8,900 feet above sea level — is melting. And as it melts, the glacier on the edge of the Tibetan plateau is retreating up the mountain faster than experts can believe.
"It's truly amazing how much it's traveled," says Barry Baker of The Nature Conservancy, part of a team of international scientists who recently visited the shrinking glacier. "It is just unbelievable."
Baker has been tracking the glacier's retreat for the past five years. He is flabbergasted by the difference since his last visit two years ago.
"The change is actually really remarkable," he says. "The glacier looks like it's gone back up the valley at least 300 feet in just the last two years."
An Astonishing Increase
Baker says the rate of retreat is increasing quickly.
"When we first started observing this glacier, it was retreating at about 80 feet per year, and now it looks like it's doubled," he says.
To explain the change, he cites an increase in temperatures.
"We've seen just in this area about a 2.2 degree increase in temperature just in the last 20 years. And it's interesting because it seems like, from the climate data that we've been studying, that this region is warming faster than some of the other parts of China. In fact, from the data that we have, this particular region is warming almost twice as fast as China," he says.
The scientists must scramble over the rocky debris, known as the moraine — left behind after the ice has melted — to move closer to the snout, or lower end, of the glacier. Studying this ice mass is extremely difficult because local Tibetans see it as a sacred glacier, and they have banned people from touching or stepping on the ice. That rules out normal scientific practices like removing ice cores and sinking stakes in the ice to measure its retreat.
The scientists have to depend on GPS measurements and repeat photography. In this, they are lucky — because explorer Frank Kingdon-Ward snapped pictures of the glacier as early as 1913. Anecdotal evidence indicates the glacier has retreated 1 1/2 miles since the late 1800s, when its tongue was close to Mingyong village.
Feeling the Albedo Effect
On this trip, the scientists note more crevasses in the ice and more wasting in the body of the glacier. An estimate by one local meteorologist says the Mingyong glacier has shrunk by 25 percent over the past 13 years, while the snowline has risen dramatically. And that leads to what is known as the albedo effect.
"On the Tibetan plateau, there's a lot of snow that has been reflecting light for a long time," explains Dominique Bachelet, The Nature Conservancy's head of climate change. "And we call it the third pole, because it has a huge impact: Reflecting the insulation from the sun means that you don't get as much warming on the globe. And so having less snow means you are going to get a lot warmer a lot faster. And when you walk by the glacier, you see all these rock falls and sediments on top of the glacier that make it dark, and so it's melting even faster now that it's totally destabilized."
That means the dripping of the glacial melt turns into a roar as the waters gather pace downstream. Baker says that's the reason the world cannot afford to ignore what is happening in a far-off village on the edge of the Tibetan plateau.
A Threat for Those Downstream
"In Northwest Yunnan, we have the upper reaches of the Yangtze River, the Mekong River, the Salween and the Irrawaddy," Baker says. "These four rivers deliver water to 10 percent of the world's population. In those upper regions, they're mostly glacier-fed, and so melting of the glaciers will have a significant impact on water for a great many people. There'll be more water for a while, but no one's really sure what's going to happen after that."
The scientists can really only guess what's happening in the upper, forbidden reaches of the glacier. But Ma Jian, who has worked on the project for four years, is pessimistic, given what he has seen and heard from the villagers.
"It's hard to tell, but maybe 10 years later, the glacier will be totally gone," he says.
That may be the worst-case scenario. One famous Chinese glaciologist estimates that almost two-thirds of the country's glaciers will have melted by 2050. That could bring ecological catastrophe for the 300 million people downstream By David Brown Washington Post Staff Writer
Depending on where you are, this is going to be a hotter, wetter, drier, windier, calmer, dirtier, buggier or hungrier century than mankind has seen in a while. In some places, it may be deadlier, too.
The effects of climate change are diverse and sometimes contradictory. In general, they favor instability and extreme events. On balance, they will tend to harm health rather than promote it.
That is the majority view of scientists trying to solve an equation whose variables range from greenhouse gas concentrations and the El Niño weather pattern to mosquito ecology and human cells' ability to withstand heat.
"We are not dealing with a single toxic agent or a single microbe where we can put our finger with certainty on an exposure and the response," said Jonathan A. Patz, a physician and epidemiologist at the University of Wisconsin at Madison. "Climate change affects everything."
Predictions of how global warming could affect people's health are crude. They are based on the experience of the past several decades, when there has been a small, well-documented rise in the temperatures of the planet's atmosphere and oceans. What that says about the future -- a time when warming is expected to accelerate, but people may be able to prepare for it -- is quite uncertain.
In the last quarter of the 20th century, the average atmospheric temperature rose by about 1 degree Fahrenheit. By 2000, that increase was responsible for the annual loss of about 160,000 lives and the loss of 5.5 million years of healthy life, according to estimates by the World Health Organization. The toll is expected to double to about 300,000 lives and 11 million years of healthy life by 2020.
The biggest tolls were in Africa, on the Indian subcontinent and in Southeast Asia. Most of that increased burden of death and disease was from malnutrition, diarrhea, malaria, heat waves and floods. But those diseases will play a minor role, at best, in many regions that nevertheless will feel the effects of global warming.
To organize their thinking -- and to focus the attention of policymakers -- researchers tend to put the health effects of climate change into five groups.
Heat Stress
The most obvious effect of global warming is hotter weather.
Scientists predict that heat waves will be longer and more frequent in the future. Their worst-case effects may have been glimpsed in Europe's summer of 2003, the hottest spell there since the 1500s. About 30,000 people died of heat-related illness, including 14,800 in France in three weeks in August.
People who were old, very young, ill, immobile or poor were at highest risk. Although the human body can adapt somewhat to chronically higher temperatures, those groups will remain vulnerable -- and they are likely to make up a bigger slice of the population in the future.
About 20 percent of people in industrialized countries are over age 60 today. That figure will rise to 32 percent by 2050. More people will also live in cities -- 61 percent of the world's population by 2030, compared with 45 percent now. Cities are "heat islands," 9 degrees Fahrenheit warmer on average than surrounding rural areas and resistant to the cooling effects of night.Aging and urbanization -- and possibly more obesity -- will put people at greater risk for heat-related illness. Nevertheless, that consequence of global warming may be easier to avoid than others, as a study published three years ago suggests.
It examined mortality on hot days in 28 cities in the last third of the 20th century. Death rates were lower in the 1980s and 1990s than in the 1960s and 1970s in most places, with the least reduction in cities of the Northeast and the Midwest. (A heat wave in Chicago in 1995 caused more than 500 deaths, the biggest U.S. toll in years.)
This steady decline in heat-stress death was almost certainly the consequence of air conditioning, better awareness of the problem and improved medical care.
"If there is a very effective response system, then even in hotter temperatures you may not see more deaths," said Kristie L. Ebi, an epidemiologist and consultant in Alexandria. She helped write the health chapter of the most recent report of the United Nations' Intergovernmental Panel on Climate Change, which was this year's Nobel Peace Prize winner along with Al Gore.
Extreme Weather
Climate change is expected to increase the severity of storms, especially ones associated with cyclical events such as the El Ni¿o Southern Oscillation.
Flooding is the most common weather disaster, responsible for the deaths of about 100,000 people and the displacement of 1.2 billion from 1992 to 2001. The worsening of this hazard will vary by region. It is expected to change little in Southeast Asia by 2030, but it may increase 50 percent in West Africa and quadruple in Central and South America.
In addition to storms, rising oceans threaten coastal populations. Of the world's 20 megacities, 13 are at sea level. Storm surges, while short-lived, can cause permanent damage, eroding land and damaging water supplies and cropland with saltwater.
When it comes to food production, climate change will have varying effects. Overall, it will tend to slow the long historical decline in the number of hungry people.
In 1990, there were 520 million people at risk of hunger, according to a study by British and American scientists published in 2005. In the absence of global warming, that number was predicted to fall to 300 million by 2080. With global warming, it is expected to fall to 380 million, although under various scenarios of greenhouse gas reductions it could drop to 320 to 340 million, according to recent mathematical modeling.
Air Pollution
Climate change affects air pollution in two ways.
Heat speeds chemical reactions and consequently may worsen pollution from ozone and airborne particulates, or soot. It may also spur pollen production by some plants, which could in turn worsen asthma and allergies in some people.Waterborne and Food-Borne Disease
Higher temperatures and torrential rains are likely to cause outbreaks of some diarrheal diseases.
The incidence of cholera -- a bacterial infection whose home is South Asia but that circles the world in slow epidemics -- depends in part on water temperatures in the Bay of Bengal and on monsoon rains. A recent study of waterborne-disease outbreaks in the United States in the past 50 years found that 67 percent were preceded by heavy rainfall.
Researchers in Australia have shown that the number of food-borne infections from salmonella bacteria goes up in hot weather.
Overall, climate change is expected to increase the burden of diarrhea, mostly in developing countries, by 2 to 5 percent by 2020.
Vector-Borne Disease
Scientists suspect that many diseases transmitted by insects and animals will become more common, although there is more uncertainty about this than other consequences of global warming.
Dengue and malaria, carried by mosquitoes, are most likely to increase. Under some projections, Africans will be exposed to malaria 25 percent more of the time in 2100 than they are now.
That risk, however, could be offset by controlling mosquitoes with pesticides, the use of bed nets by children and pregnant women, and better medical care.
Other diseases that may become more prevalent are yellow fever (also carried by mosquitoes), schistosomiasis (by snails), leishmaniasis (sand flies) and Lyme disease (ticks).
The Role of Planning
In the United States, most public discussion of global warming has been about ways to slow the phenomenon, and not about ways to dampen or prevent effects that are already inevitable.
"We are a good decade behind Europe in designing and developing adaptations that will decrease our vulnerability and increase our resilience," said Ebi, the epidemiologist.
Such planning is wise not only for the federal government and states, but for cities and towns as well, Ebi believes.
"The impacts of climate change really do depend on your local context," she said
COLUMBUS, Ohio—In a mission of unprecedented scale, scientists are about to cover West Antarctica with a network of sensors to monitor the interactions between the ice and the earth below—24 hours a day, 365 days a year.
The National Science Foundation (NSF) just awarded the collaboration, called POLENET, $4.5 million to plant global positioning system (GPS) trackers and seismic sensors on the bedrock that cradles the West Antarctic Ice Sheet (WAIS). Lead institution Ohio State University will receive more than $2.2 million, and the rest will be divided among partners in the United States as part of an International Polar Year project.
As scientists have tried to understand how climate change is affecting the WAIS, they have long wished they could gather information from the entire region, explained POLENET leader Terry Wilson. But Antarctica contains the coldest and windiest sites on the planet—locations inhospitable to scientific instruments and the scientists who would deploy them.
In a presentation Tuesday, December 11, 2007 at the American Geophysical Union meeting in San Francisco , she described how her team will overcome the harsh environment. They’ll fly ski-equipped aircraft to remote locations, and plant rugged instruments that will send signals back to the United States via satellite. “We’ll be able to do systems-scale science in Antarctica . That wasn’t possible before,” said Wilson, associate professor of earth sciences at Ohio State. “This instrumentation is designed to run and record data year-round, through the dark polar night. Previous instrument deployments have largely operated only for a few months, or less, each year. This allows us to do new science.”
In a related project over the summer of 2007, POLENET scientists installed two dozen GPS trackers in Greenland . By the end of February 2008, the scientists plan to have 17 new trackers installed around the WAIS, along with about 11 new seismic sensors. The first expeditions began arriving in Antarctica early in December, 2007. The network will be complete in 2010 and will record data into 2012. Selected sites may remain as a permanent Antarctic observational network.
Scientists around the world will be able to access POLENET data online, and schools will be able to access educational resources.
Ohio State’s POLENET partners in the United States are Pennsylvania State University, the University of Texas at Austin, New Mexico Tech, Washington University, the Jet Propulsion Laboratory, and the University of Memphis. A host of international partners are part of the effort as well.
WASHINGTON - Warming of the earth's atmosphere will continue to put mounting pressure on America's drinking water sources, leading to diminishing supplies in some regions and flooding in others, according to an analysis released today by the Association of Metropolitan Water Agencies (AMWA), a nonprofit organization of the largest publicly owned drinking water systems in the United States.
AMWA's report, Implications of Climate Change for Urban Water Utilities, forecasts the likely impacts of climate change on water supplies in different regions of the U.S., such as an accelerated hydrologic cycle of evaporation and precipitation, water contamination, rising sea levels and pressure on terrestrial and aquatic ecosystems. The report is available for viewing and download at AMWA's new climate change webpage, www.amwa.net/cs/climatechange.
The national debate on climate change has so far been limited to the effects of greenhouse gases," said AMWA Executive Director Diane VanDe Hei. "For community drinking water systems, climate change has broader implications. The question we ask is: 'To what extent will our water supplies be affected?'"
This report shows that climate change may pose great challenges to delivering limited amounts of clean and safe water to a rapidly growing population," added VanDe Hei.
Among the actions that the report suggests water systems take to prepare for the impacts of climate change are vulnerability assessments to identify short-term adaptation needs; cooperative planning and modeling efforts among utilities to devise strategies addressing likely regional water resource issues; and efforts by utilities to reduce their own greenhouse gas emissions.
"The ramifications identified in the report point to at least two key needs," said VanDe Hei. "Scientific research is needed to better understand the impacts of climate change on existing fresh water resources and to help develop and assess the affordability of alternative water sources -- such as reuse, recycling, conservation and desalination."
"In addition, an increased federal investment in water infrastructure is needed to help offset the costs of new supply development and capital projects to ensure that all Americans continue to have access to safe and affordable drinking water," she said.
In conjunction with the release of the report, AMWA's new climate change webpage will serve as a resource for water utility managers and policy makers seeking the latest information on the impacts of climate change on drinking water supplies. The page includes fact sheets and presentations on local impacts of climate change, and can be viewed at www.amwa.net/cs/climatechange.
Source: Association of Metropolitan Water Agencies
The global scientific consensus is that man's habit of belching greenhouse gases into the atmosphere is destabilising the climate. To save ourselves from catastrophe we must urgently cut those emissions. Governments must set binding targets to achieve those cuts. That is broadly the international political consensus too, with two caveats. The US does not want to commit to targets independent of the developing world, which is catching up fast in terms of carbon output. And developing countries, chiefly China and India, reserve the right to catch up with the West before subjecting themselves to the same level of carbon austerity.
The Bali compromise, roughly speaking, is that rich nations agree to transfer green technology to poorer ones and specific targets for emissions cuts - championed by the EU - are relegated to a footnote.
The US, China and India, are labouring under a false assumption - that cutting emissions means surrendering economic virility. But once the disastrous consequences of inaction are taken into account - natural disasters; refugee crises; food shortages - it becomes clear that, aside from the moral imperative, there is a huge competitive edge available to the countries that first make the transition to a low-carbon economy.
Thankfully, American public opinion, and some individual US states, which have set unilateral emission targets, are closer to understanding this than George Bush and his administration. The next US President, whether Republican or Democrat, will surely take note of that
Sceptics are right to worry that Bali did not deliver a carbon-cutting breakthrough. But as a statement of intent it signals real progress. At least politicians are catching up with the basic science of climate change. Now they just need to catch up with the scientists' - and increasingly the public's - sense of urgency.
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