(AP Photo/Luigi Costantini)

For the first time, the world’s top climate change scientists have endorsed an upper limit on greenhouse gas emissions, establishing a target level for curbing emissions that if not achieved could lead to irreversible and potentially catastrophic climatic changes.

In a report released today by the Intergovernmental Panel on Climate Change (IPCC), the UN’s climate panel, scientists also said that the target is likely to be exceeded in a matter of decades unless steps are taken soon to reduce emissions. To contain these changes will require “substantial and sustained reductions of greenhouse gas emissions,” the scientists said.

The panel hopes that its latest report will help move international policymakers toward agreement on a new climate treaty, as negotiations have stalled in recent years. The report also concluded that many of the observed changes in climate since 1950 were “unprecedented over decades to millennia” and that over half of the temperature increases were man-made.

“Our assessment of the science finds that the atmosphere and ocean have warmed, the amount of snow and ice has diminished, the global mean sea level has risen and that concentrations of greenhouse gases have increased,” said Qin Dahe, co-chair of the IPCC working group that produced the report.

In reaction to the news, Kumi Naidoo, the executive director of Greenpeace International, said: “The IPCC warns of an alarming escalation of impacts but also shows that preventing climate chaos is still possible.”

“The IPCC warns of an alarming escalation of impacts but also shows that preventing climate chaos is still possible.” — Kumi Naidoo, Greenpeace International

Speaking at a press conference in Washington, DC, Naidoo added that the panel’s warnings call for immediate action. He also pointed to the on-going situation regarding Greenpeace activists who are being held in Russia after they protested oil drilling in the Arctic.

“Unfortunately those who are taking this action are now in prison in Russia, while those that are most responsible are protected by governments around the world,” Naidoo said. One of the main obstacles to addressing climate change is a lack of political will, in particular on agreements that would create legally binding and internationally enforceable targets for reducing greenhouse gas emissions.

Window of opportunity

Naidoo talked about the urgency of these issues in this weekend’s interview with Bill Moyers. As the Arctic melts and sea levels rise, Naidoo said bold steps are needed on the part of policymakers in the international community to create an “energy revolution” to ensure carbon emissions drop dramatically.

“There is a small window of opportunity in terms of time. I would say no more than five to ten years,” Naidoo told Bill. “And, based on current practices of governments, if we continue like that over the next coming years, then sadly, I think it will be too late,” Naidoo said.

The IPCC concluded in its report that to keep emissions below the internationally agreed upon target of 3.6 degrees Fahrenheit (2 degrees Celsius) no more than one trillion metric tons of carbon can be burned and the resulting gas released into the atmosphere.

More than half that amount has been emitted since the beginning of the Industrial Revolution. According to calculations by one of the report’s authors, the trillionth ton of carbon will be sent into the atmosphere around 2040.

A separate study released earlier this year found that, to give humanity a 75 percent chance of not exceeding the 2 degree Celsius mark, global emissions will have to peak by 2015 and decline by five percent annually thereafter.

Point of no return?

The Greenpeace International study, “Point of No Return,” pinpoints a number of enormous planned energy projects that would “cause massive climate threats,” which would likely cause humanity to exceed the 2 degrees Celsius point.

“Burning the coal, oil and gas from the 14 massive projects would significantly push emissions over what climate scientists have identified as the “carbon budget,” the amount of additional CO2 that must not be exceeded in order to keep climate change from spiraling out of control,” Greenpeace said in a statement.

Reducing and eventually phasing out emissions through a variety of measures is the cornerstone of Greenpeace’s policy recommendations. The organization is also calling for investment in renewable energy sources and establishing legally binding targets for their use.

Greenpeace said moving forward with these planned projects could lead to dire consequences in the coming years. “The costs will be substantial: billions spent to deal with the destruction of extreme weather events, untold human suffering, and the deaths of tens of millions from the impacts by as soon as 2030,” Greenpeace said.

Last week, at the House Energy and Commerce Committee hearing on President Obama’s climate action plan, Secretary of Energy Ernest Moniz suggested a time frame similar to that given by Naidoo to act on climate change. “In my view, this decade is the critical one [because] the CO2 problem is cumulative. And every ton we emit, you can check it off against our children and grandchildren,” Moniz said.

Obama’s plan

In June, President Obama revealed a plan for tackling climate change in hopes of meeting the pledge he made in 2009 to reduce America’s greenhouse gas emissions by 17 percent from 2005 levels by 2020.

The core of his strategy calls for reducing carbon emissions at power plants while also allocating new federal funds to advance renewable energy technology. Obama said he would use his executive powers to require carbon reductions at the nation’s power plants.

Many agree that continuing with business as usual in terms of climate change would be disastrous, with widespread changes in weather patterns and sea level rises that will submerge many coastal communities.

The poor around the world will be hit the hardest, and we will see a growing number of conflicts in already-unstable regions exacerbated by the shifting climate. In fact, Americans — and others around the world — are already noticing the devastating effects.

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