(July 24*) Melting Arctic ice releasing banned toxins, warn scientists

• Unknown amount of trapped persistent organics pollutants poses threat to marine life and humans as temperatures rise
• 
  
• Damian Carrington
• guardian.co.uk, Sunday 24 July 2011 18.00 BST
• Article history

Melting Arctic ice is allowing chemicals to seep out, including the pesticides DDT, lindane and chlordane, as well as PCBs. Photograph: AlaskaStock/Corbis

The warming of the Arctic is releasing a new wave of toxic chemicals that had been trapped in the ice and cold water, scientists have discovered.

The researchers warn that the amount of the poisons stockpiled in the polar region is unknown and their release could "undermine global efforts to reduce environmental and human exposure to them".

The chemicals seeping out as temperatures rise include the pesticides DDT, lindane and chlordane, made infamous in Rachel Carson's 1962 book Silent Spring, as well as the industrial chemicals PCBs and the fungicide hexachlorobenzene (HCB).

All of these are know as persistent organics pollutants (Pops), and are banned under the 2004 Stockholm convention.

Pops can cause cancers and birth defects and take a very long time to degrade, meaning they can be transported for long distances and accumulate over time. Over past decades, the low temperatures in the Arctic trapped volatile Pops in ice and cold water.

But scientists in Canada and Norway have discovered that global warming is freeing the Pops once again. They examined measurements of Pops in the air between 1993 and 2009 at the Zeppelin research station in Svalbaard and Alert weather station in northern Canada.

After allowing for the decline in global emissions of Pops, the team showed that the toxic chemicals are being remobilised by rising temperatures and the retreat of the sea ice, which exposes more water to the sun. For example, air concentrations of PCBs and HCBs have shown a rising trend from about 2004 onwards. The scientists' work is published in the journal Nature Climate Change.

Hayley Hung, at the air quality research division of Environment Canada and one of the team, said their work provided the first evidence of the remobilisation of Pops in the Arctic. "But this is the beginning of a story," she said. "The next step is to find out how much is in the Arctic, how much will leak out and how quickly."

Hung said, with the exception of lindane, there was little existing knowledge of the scale of the Pops stored in high latitude regions.

The fate of the frozen Pops depends on the speed of warming in the Arctic – it is currently heating up much more quickly than lower latitudes – as well as how the chemicals interact with snow and rain.

Pops accumulate in fats and are therefore concentrated up the food chain, but Hung cautions that food chains themselves in the Arctic may be altered by climate change.

Retrieved from http://www.guardian.co.uk/world/2011/jul/24/melting-arctic-ice-banned-toxins-pops?CMP=twt_fd

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(Dec 11, 2010*) Cancun paves way for global climate treaty

Dec 11, 2010 - 18:28

by Jessica Dacey in Cancun, swissinfo.ch

Switzerland has welcomed a new United Nations deal thrashed out in Cancun, saying it heralds the birth of an international treaty on climate change.

Over 190 nations meeting in the Mexican resort adopted the two-part climate agreement on Saturday.

The deal, brokered by Mexico, includes the creation of a Green Climate Fund and steps to help share clean technologies such as wind and solar power, protect tropical forests and assist poor nations to adapt to impacts such as floods, droughts and rising sea levels.

The final result offers a “solid basis for development” on issues in the coming years and primarily, for next year’s climate summit in South Africa, Switzerland’s top negotiator Bruno Oberle told swissinfo.ch in Cancun.

A “fairly impressive” list of promises by developed and developing countries had been incorporated in the deal, said Oberle, who heads the Swiss Federal Environment Office.

The current climate treaty is now 20 years old, and no longer reflects today’s global emissions situation, he said. It was time to find a way of bringing developed and developing countries together to take responsibility for their share in the bigger climate picture.

Cancun has taken a step in that direction with a document that “provides one overarching framework for all countries".

The same sentiment was expressed by the president of conference of the UN Framework Convention on Climate Change, Mexican Foreign Secretary Patricia Espinosa, who announced the conclusion of the agreement saying the “historic” deal signaled “a new era in international cooperation in climate change”.

The European Union's climate commissioner Connie Hedegaard, also commented that Cancun “proved that multilateralism can create results".

“Step backwards”

Draft texts were formally endorsed at a final session at 4am local time, after non-stop negotiations among delegations through Thursday and Friday. It passed despite solitary opposition from Bolivia.

The South American nation said it was opposed to the deal as it represented a “step backwards” and would result in a “weaker, less demanding, regime for developed countries which are responsible for global warming”.

Mexico said Bolivia’s objections were “duly reflected in the conference records”.

Bolivia was criticised during the week for its hardline approach, the toughest of any nation at the talks, demanding that rich nations halve their greenhouse gas emissions by 2017 from 1990 levels - far beyond the demands of other nations.

A new fund

The Cancun agreement was the first time in three years that the 193-nation conference had adopted any climate action, restoring faith in the UN process after failed talks in Copenhagen in 2009.

The deal integrates the pledges for action made in the Copenhagen Accord into the UN climate process. But it does not require developed countries to adopt binding cuts beyond the Kyoto Protocol, which runs out in 2012.

Delegates put off the Kyoto issue until next year’s conference in South Africa, but states party to the protocol will be obliged to intensify their efforts to reduce greenhouse gas emissions.(Switzerland’s commitment for a second Kyoto period from 2013- 2020 is currently before the Swiss parliament.)

In creating a new climate fund, richer nations have promised to contribute $100 billion a year by 2020, but the Cancun decision does not identify specific sources of financing. The fund will be used to help developing nations obtain clean technology and adapt to climate change.

Switzerland noted that it helped push through with the climate fund with a proposal on how it should be organised, and through its staging of the Geneva Dialogue on Climate Finance earlier this year.

Great challenge

Oberle said Cancun also helped answer a key question about the climate issue, namely, “who is responsible for what in the field of mitigation” of the effects of environmental changes.

He was referring to the planned framework of measures aimed at helping in particular the very vulnerable developing countries to adapt to climate change and to mitigate its impact on them. (See Cancun deal highlights).

The deal also takes a position on climate change, saying it is one of the greatest challenges facing humanity and calling for a paradigm shift to enable the development of a climate-friendly economy and society.

Outside the plenary session, Patrick Hofstetter, spokesman for the Swiss Climate Alliance, told swissinfo.ch he was satisfied with the outcome, but noted it was “just one important step”.

On a positive note, no issues were left out of the Cancun agreement, but the deal was problematic as most of the processes decided had no clear end date nor was it obvious how they would evolve, he said.

“So it’s very open whether we will have something in one, three or five years. This is a big problem so it needs a lot of work next year in order to finalise everything in South Africa.”

Observing the Cancun summit from Switzerland, Oberle’s predecessor, Philippe Roch, now an environmental consultant, noted that trust between nations had been restored during the negotiations, which was in itself a “very positive factor”.

“After Copenhagen there were huge doubts about whether countries could work together. Trust is necessary,” he said, cautioning however that “we have not yet reached a paradigm shift in our consumer behaviour or attitudes about carbon usage.”

Jessica Dacey in Cancun, swissinfo.ch

Retrieved from http://www.swissinfo.ch/eng/specials/climate_change/news/Cancun_paves_way_for_global_climate_treaty.html?cid=29005802

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(June 24*) Uncertainty hinders Kyoto successor

June 24, 2011 - 14:16

by Pierre-François Besson, swissinfo.ch

With no agreement on a new time frame, a gap is looming after the end of the first commitment period (2008-2012) to reduce emissions under the Kyoto Protocol.

Kyoto risks collapse due to lack of support beyond 2012 from rich nations, which are meant to take the lead in fighting climate change.

"This process is dead in the water," said Yvo de Boer, the former head of the United Nations Climate Change Secretariat.

"It's not going anywhere," he said during the United Nations June 6-17 talks in Bonn, which yet again failed to resolve disputes between rich and poor about extending the Kyoto Protocol.

On one side Japan, Russia and Canada say they will not sign up for deeper cuts in emissions under Kyoto beyond 2012, arguing that a global deal, backed by all big emitters including China and India, is a fair next step.

But developing nations say Kyoto is a test of developed countries' past promises to lead in slowing global warming, which is set to cause more heat waves, droughts, floods and rising sea levels that are likely to hit the poorest hardest.

Another preparatory meeting is expected to be scheduled before the next big Conference of Parties (COP) meeting in Durban, South Africa five months away.

Added to the United Nations Framework Convention on Climate Change, the Kyoto Protocol legally obliges a minority of states, known as Annex I countries to reduce their greenhouse gas emissions.

Annex I countries agreed to reduce their collective greenhouse gas emissions by 5.2 per cent from the 1990 level. One year before the end of the first commitment period these states have failed to deliver, some falling far short of their reduction target.

The Annex I countries were deemed “industrialised” when Kyoto was initially adopted in 1997. However, they produce a small share of the global greenhouse gas emissions, according to Jorge E. Viñuales, chair of international environmental law at the Graduate Institute in Geneva.

“At the time the industrialisation of China had not been foreseen and the vision of the future was still marked by the Cold War,” Viñuales said. “Kyoto does not tie the United States [which has signed but not ratified] or China or the emerging economies who produce most of the emissions.”

Kyoto’s value

“The actual contribution of Kyoto to the reduction of emissions is very limited. The value of the protocol is in having been a first experience in how to make a treaty limiting emissions,” said Viñuales.

Judged strictly on its climate impact, Kyoto performs poorly. The emissions reductions to which the states are committed are minimal, according to Viñuales.

“And even if we arrived at zero emission, that would not be enough. The average temperature will increase anyway by two degrees or more by the end of the century. The stock of greenhouse gases in the troposphere is already too high. Which is why geo-engineering is so important [reforestation, injection of particules into the atmosphere etc].”

Kyoto does have some merit both as a negotiation instrument and for the impetus it creates. Its very existence has encouraged the private sector to be more efficient and it can be used by governments to justify unpopular decisions.

The Protocol is also a diplomatic instrument. China and the emerging economies support it to push the industrialised countries to commit before asking the same effort of them. And Canada and the European Union (with Switzerland) refuse to be tied and to unilaterally reduce their competitiveness if the big emitters do not commit. That largely explains the current impasse.

No clear signal

The legal void expected after 2012 will mean the absence of a clear signal allowing the business world to make good energy and industrial investment choices.

For Viñuales this absence of international commitment will spur companies to “deploy every possible lobbying effort to limit as much as possible the weight of the national regulation on emission reduction”.

Annex I countries whose emissions exceed 1990 levels by the end of next year will in theory breach their commitments. But Kyoto has built-in flexibility mechanisms. The best known is the trading of emission rights. It allows countries to buy emission credits from countries which emit less than their quotas.

This mechanism – like other instruments set up by the protocol – will survive thanks to the well-established European trading system, Viñuales predicts. The Geneva professor already envisages three post-Kyoto scenarios without Kyoto II in place.

Three scenarios

“The first, quite likely, scenario is a return to the framework convention, where the non-binding obligations would be set by the COP. That would give a substantial, non-obligatory framework, which would send a strong, international and largely harmonised signal to the private sector.”

Another possibility would be to go down the human rights route, in other words employing the mechanisms and instruments in this domain to obtain damages and compensation from the big emitters. This route is currently being explored by the High Commissioner for Human Rights, according to Viñuales.

The third scenario is that of atomisation: “A mosaic of national regulations without coordination of common obligations”. Viñuales can also easily imagine a combination of the three. The Durban meeting could make things clearer.

Pierre-François Besson, swissinfo.ch
(Adapted from French by Clare O'Dea)

Retrieved from http://www.swissinfo.ch/eng/specials/climate_change/news/Uncertainty_hinders_Kyoto_successor_.html?cid=30540042

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(July 12*) High-powered lobby calls on Canada to wean itself off oil

By Mike De Souza, Postmedia News July 12, 2011

OTTAWA — A wide-ranging group of businesspeople, scientists, investors, municipal leaders and non-profit organizations is urging Canadian energy ministers to use an upcoming national summit to move away from oil, gas and coal and toward a greener economy.

"It's hugely unfortunate that we've waited this long," said Andrew Heintzman, president of Investeco Capital, a Toronto-based firm that invests in clean technology companies or environmentally-friendly products, managing about $40 million in assets for about 100 investors.

Heintzman said he favours immediate action by governments to lead Canadians away from oil and other fossil fuels as part of a long term transition over the next few decades.

"That's not to say you wait until the 49th year and make your change," said Heintzman. "You got to get on it right now and we have to start putting in place the policies that are going to drive a transformative change."

Heintzman and other stakeholders supporting the plan were brought together by Tides Canada, a non-profit group promoting a healthy environment and social justice. It believes that oil, coal and gas will be "supplanted by clean and plentiful alternatives" by 2050. It also believes that economic prosperity can be linked directly with deep cuts in greenhouse gas emissions that are normally produced through consumption of fossil fuels.

Merran Smith, the director of the Tides Canada Energy Initiative, said the stakeholders also hope this message gets through to federal, provincial and territorial energy ministers who are scheduled to meet later this month in Kananaskis, Alberta.

Smith said that a global energy transition is already underway, with leading economies such as the United States, China and the European Union making huge investments in renewable energy.

"For Canada to maintain its position as an energy superpower, we need to evolve to be a clean energy superpower," she said. "Canada has the opportunity to do that, because we are blessed with such an abundance of hydro, wind, biomass and other renewable energy sources."

The message supported by stakeholders was based on a policy paper released last spring by Tides Canada that envisions a future with more energy-efficient buildings and cleaner transportation networks in Canada that produce less pollution by 2050.

"It paints a picture of Canada that has moved on as a society that uses very little hydrocarbons (for fuel) and is predominantly powered by clean renewable energy sources," said Smith.

The list of stakeholders supporting the policy paper include the City of North Vancouver, Mayor Ken Melamed from Whistler, British Columbia, as well as scientists Andrew Weaver from the University of Victoria and David Keith from the University of Calgary.

Several faith-based groups also have signed on to support the effort from a variety of different religions.

mdesouza@postmedia.com

Twitter.com/mikedesouza

© Copyright (c) Postmedia News

* Retrieved from http://www.vancouversun.com/business/High+powered+lobby+calls+Canada+wean+itself/5091629/story.html

* Color and emphasis added by the blogger

(July 16*) Australia’s PM shows political courage on climate change

JEFFREY SIMPSON | Columnist profile | E-mail

From Saturday's Globe and Mail

Published Saturday, Jul. 16, 2011 2:00AM EDT

Last Sunday night, the Prime Minister of Australia went on national television.

Prime ministers in democratic countries take to the airwaves only if they have something extremely important to say. And Prime Minister Julia Gillarddid. She said something inconceivable in Canada, at least under Stephen Harper’s government.

“Most Australians now agree our climate is changing,” she said. “This is caused by carbon pollution. This has harmful effects on our environment and on the economy. And the government should act.”

And act it did. Next July 1, the Australian government will put a price of $23 a tonne on carbon for the country’s 500 largest emitters. Three years later, the government will convert that tax into an emissions trading scheme, or cap-and-trade, whereby the government will mandate emission limits and let the market set the price.

At a press conference, Ms. Gillard explained her thinking: “The avalanche of science tells us our climate is changing. The science is in. We know that out planet is warming. We know that warming is changing our climate.”

Climate change has been a political killer in Australia. Former Liberal (conservative) prime minister John Howard did little about it. His successor, Labor prime minister Kevin Rudd, failed to get serious measures approved. He had a deal, or so he thought, with the then Liberal leader, only to have ferocious climate change skeptics dethrone that leader. Mr. Rudd himself then was deposed in a political coup by Ms. Gillard.

She leads a minority Labor government, propped up by independents and Greens who began holding the balance-of-power in the Senate on July 4. To survive, she had to provide something that would satisfy her own party and the Greens.

She settled on a carbon tax on big polluters, followed by the cap-and-trade, with the money flowing into government coffers flowing back out in the form of tax cuts, support for energy efficiency, renewable energy and assistance for industries such as coal and steel that will struggle to reduce emissions. The country’s overall target will be to reduce emissions by 80 per cent of the 2000 levels by 2050.

Can Australia do it? Like Canada, Australia is a major user and exporter of fossil fuels. Replacing coal will be very hard. Getting this policy to stick will also be very hard, since Ms. Gillard’s popularity is low, and her Liberal opponents are strongly opposed to any serious measures to combat climate change.

She has two years until the next election, and it will be tough sledding to sell this policy, especially when the international community is making such little progress toward any kind of global agreement. Meanwhile, the terrible decade-long drought that struck Australia, and caused climate-change concerns to soar, ended last year.

In Canada, critics of a carbon tax predict economic disaster. In Australia, the Treasury department modelling shows a 10th-of-1-per-cent drop in economic output, but a continuation of strong economic growth and job creation for the next decade. Every taxpayer earning less than $80,000 will get a tax cut of at least $300 to offset what the government correctly assumes will be the result of companies passing on some of the carbon tax in higher prices.

Australia’s proposed carbon tax is about the same as British Columbia’s, but higher than the $15-a-tonne tax Alberta imposes on some companies. It’s less comprehensive than B.C.’s tax, which applies to fossil fuels everywhere, not just big emitters. But it does roughly follow the B.C. commitment to recycle money from the carbon tax to lower taxes on individuals. It’s not the “broad-based carbon pricing scheme” vaguely proposed by Canada’s Council of Chief Executives, since the Australian scheme hits the industrial emitters.

The Australian scheme does show political courage. It also grasps the essence of any serious attack on carbon emissions – that a price has to be put on these emissions.

Any other approach is bound to fail. Regulations and subsidies, the chosen means of the Harper government, will be an expensive failure, as they have been when used elsewhere. But then this government remains indifferent to climate change, unlike our Australian cousins.

* Retrieved from http://www.theglobeandmail.com/news/opinions/opinion/australias-pm-shows-political-courage-on-climate-change/article2099056/

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(July 18*) Will the Real Global Warming Alarmists Please Stand Up?

Posted: 7/18/11 09:21 AM ET

Kelly Rigg Executive Director, GCCA

I wish I had a dollar for every time someone called Al Gore an alarmist.

The dictionary definition of an alarmist is "someone who is considered to be exaggerating a danger and so causing needless worry or panic," "a person who habitually spreads alarming rumors, exaggerated reports of danger, etc." Not to be confused, of course, with someone who sounds the alarm about a genuine threat. Someone who shouts "Fire!" in a movie theater is a villain if there's no fire, but a hero if there is.

In the case of climate change, 97% of climate experts -- the scientists who publish in peer-reviewed journals -- agree that the climate is changing as a result of human activity. Given the dramatic scale of current and anticipated impacts, this is akin to a fire smoldering in the projection room.

But what about those who shout "fire!" in relation to measures aimed at eliminating energy waste and our dependency on fossil fuels? This is the other side of the alarmist coin.

This kind of alarmism has led to a spate of death threats against climate scientists, most recently in Australia where a heated public debate over a proposed carbon tax is currently raging. I'm not referring to the run-of-the-mill creepy, anonymous emails that many of us receive from time to time, but to blatant and open hate-mongering. Take the example of German physicist Hans Schellnhuber, who spoke at a conference in Melbourne recently. Accused of being a "green fascist," his speech was interrupted by a member of the audience brandishing a hangman's noose (you can watch it for yourself here).

Or how about Christopher Monckton, currently touring Australia to whip up opposition to the carbon tax? He calls his critics fascists, yet without the slightest hint of irony makes this threat against climate scientists: "So to the bogus scientists who have produced the bogus science that invented this bogus scare, I say, we are coming after you, we are going to prosecute you and we are going to lock you up!" (You can hear it on this Australian Broadcasting Corporation ABC program at 5.08 minutes).

Leave aside the relative merits of the scientific arguments. (Monckton's were thoroughly discredited in the ABC program, as well as in a recent BBC documentary called Meet the Climate Skeptics.) Check outSkeptical Science for a comprehensive inventory of claims and responses to skeptic arguments.

Let's look instead at the arguments of the 'Progress Alarmists,' i.e. those who apparently believe that solving the climate problem will bring an end to civilization as we know it. It's a curious position given the myriad non-climate benefits to be had from getting off fossil fuels. Here are the two most common:

1) "It costs too much." This is a favorite argument for inaction. But a new peer-reviewed report concludes "the damages from a ton of carbon dioxide emissions in 2050 could equal or exceed the cost of reducing emissions at the maximum technically feasible rate. In other words, it is unequivocally less expensive to reduce greenhouse gas emissions than to suffer climate damages."

This is consistent with the findings of the seminal review on the economics of climate change, led by Lord Nicholas Stern in 2006:

The evidence shows that ignoring climate change will eventually damage economic growth. Our actions over the coming few decades could create risks of major disruption to economic and social activity, later in this century and in the next, on a scale similar to those associated with the great wars and the economic depression of the first half of the 20th century. And it will be difficult or impossible to reverse these changes. Tackling climate change is the pro-growth strategy for the longer term, and it can be done in a way that does not cap the aspirations for growth of rich or poor countries. The earlier effective action is taken, the less costly it will be.

2) "It curtails freedom," or any number of variations on that theme that imply national sovereignty is subjugated to the United Nations (hint: it won't). Last week's Congressional 'Battle of the Bulb' is a classic example of 'Progress Alarmism' and one that has left even me scratching my head.

A law signed by George W. Bush in 2007 (with the support of manufacturers!) requires a 30% increase in the efficiency of light bulbs, with savings to consumers estimated at around $100-$200 per year for a total of $15 billion per year. In practice, this spells the end of old-style incandescent bulbs, although newer more efficient versions will still be available in addition to compact fluorescents, LEDs and others that meet the standard. In an effort to overturn the regulation, Rush Limbaugh has attacked it as a form of "nannyism, statism" and Tea Party favorite Michele Bachmann referred to it as "an issue of freedom. It's about whether people are able to make even the most basic decisions anymore or whether Big Brother will control every aspect of their lives."

Shall we compare those comments with their positions on, let's see now, gay marriage? flag burning? smoking marijuana? and see if the freedom argument holds water? Inconsistency aside, the fact is that climate change knows no borders and therefore requires a cooperative international approach to deal with it. Any country that exercises its freedom to profligately pollute ultimately condemns other countries to annihilation. And if you think that's an alarmist exaggeration, ask the people of Tuvalu or the Maldives. It's the equivalent of demanding the right to shout "fire" in the cinema on principle.

So the next time you hear claims like Limbaugh's or Bachmann's (Big Brother? Control over every aspect of our lives? Really?) ask yourself who the real alarmist is.

* Retrieved from http://www.huffingtonpost.com/kelly-rigg/battle-of-the-bulb-expose_b_901248.html?ref=fb&src=sp#sb=1431305,b=facebook

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(Oct 6, 2009*)The Science of 350, the Most Important Number on the Planet

by Bill McKibben, 350.org on 10. 6.09

BUSINESS & POLITICS

Photo courtesy 350.org

350 is the most important number on the planet.

Which is odd, because until about 22 months ago no one even knew it mattered.

But that's when, in December of 2007, NASA's Jim Hansen gave a slide show at the American Geophysical Union annual meeting in San Francisco. He'd been thinking about what it meant that we'd just come through a summer of very rapid ice melt in the high Arctic, and that researchers were reporting "ahead of schedule" changes in dozen other of the earth's big physical features--melting glaciers, acidifying oceans and so on.

Combined with reams of paleo-climate data, his team believed they now had enough information to finally draw a red line for the planet: when atmospheric concentrations of carbon dioxide were above 350 ppm, they said, global warming would be dangerously out of control. In fact, they said in the abstract of the paper they soon published, above 350 you couldn't have a planet "similar to the one on which civilization developed and to which life on earth is adapted."

It's as if we suddenly discovered what normal body temperature was, so we'd be able to tell when we were running a fever. In that sense, it came as a great relief.

But in every other sense, it was a pretty devastating number. For one thing, we're already past it, at 390 ppm and rising two ppm annually--that's why the Arctic is melting. For another thing, it means the work nations and individuals must do to reduce their carbon footprints is much larger, and must happen much more swiftly, than we'd believed. Hansen's data shows that as a planet we'd need to get off coal by 2030 in order for the planet's forests and oceans ever to bring atmospheric levels back down below 350--that's the toughest economic and political challenge the earth has ever faced.

But it's not as if we have a choice. The most useful thing about having a number is that it forces us to grow up, to realize that the negotiations that will happen later this fall in Copenhagen aren't really about what we want to do, or what the Chinese want to do, or what Exxon Mobil wants to do. They're about what physics and chemistry want to do: the physical world has set its bottom line at 350, and it's not likely to budge.

Almost every month brings new data showing that Hansen et al were very nearly spot on with their original estimate. In early summer a British team demonstrated that coral reefs won't survive acidified waters unless we get co2 concentrations back down below 360 ppm. Last month, in a cover story in the journal Nature, a European-led team identified nine "planetary boundaries," the most important of which was probably that same 350 ppm line for carbon. Above it, they said, we would run the risk of "threatening the ecological life-support systems that have developed in the late Quaternary environment, and would severely challenge the viability of contemporary human societies." The name of the article: "A Safe Operating Space for Humanity." That's what we're talking about.

* Retrieved from http://www.treehugger.com/files/2009/10/the-science-of-350-the-most-important-number.php

* color and emphasis added by the blogger