This article is from the archive of our partner National Journal

The surprising deal announced between China and the U.S. on Tuesday that gives both nations long-term carbon-reduction targets has upped the game ahead of international climate negotiations next year.

Under the deal, China will cap emissions by 2030, although a peak could come earlier. And the U.S. agreed to greenhouse-gas cuts of 26 to 28 percent below 2005 levels by 2025, an extension of the current pledge to cut 17 percent by 2020.

But can the countries deliver on their deals? And if they do, how much difference will it actually make to protecting the planet's climate? Scientists aren't so sure.

How big of a deal is this agreement?

It's historic. The agreement marks the first time China has pledged to cap its emissions within a set time frame. As the largest polluter in the world, China is an essential player in any kind of effort to tackle global warming.

"From a climate perspective, the most important goal right now is to stop global emissions from continuing to rise. That can't happen until China's emissions peak. So this is announcement is absolutely critical as a first step," said former Clinton White House official and German Marshall Fund senior fellow Paul Bledsoe.

The significance of the world's two largest polluters coming to terms on climate months ahead of the do-or-die negotiations in Paris next year is hardly lost on supporters. But digging into the numbers has left some wanting more.

Erich Pica, president of the U.S.-based Friends of the Earth, said in a statement that the targets should become "a very low floor for presidential aspirants and not a ceiling for what is possible in the United States." The target, he said, was "grounded in neither the physical reality of climate science nor the lived reality of hundreds of millions of people in developing countries whose lives and livelihoods are in jeopardy."

"Simply put, the non-binding target falls miserably short of what science, justice, and equity demand."

Does this solve global warming?

In a word, no. The deal sets the stage for nations to negotiate a global agreement on climate change next year, with the goal of keeping the climate from warming 2 degrees Celsius above pre-industrial levels—a scientific benchmark for averting dangerous climate impacts. But a number of scientists say China's pledge falls short of what is needed to hit that target.

Instead, several scientific estimates predict that China's emissions would need to peak between 2020 and 2025 to give the world a decent shot of meeting the 2-degree target.

"You often hear people say we have to act in the next 10 years. I would say we should have acted 10 years ago," said Glen Peters, a senior research fellow with the Center for International Climate and Environmental Research in Oslo. "It is really very difficult to stay below 2 degrees Celsius."

In an interview with Reuters, Rajendra Pachauri, who heads the U.N.'s Intergovernmental Panel on Climate Change (IPCC) acknowledged that the pledge alone did not follow the path to zero net emissions by 2100, the path laid out by his panel in its most recent report as necessary to avoid the worst impacts of climate change.

Cambridge researcher Chris Hope went further, saying that "statements about [the agreement's] ambition should be treated with caution." Even with the agreements, Hope's projection model only gives the world a less than 1 percent chance of staying below the 2-degree benchmark. Accounting for the developing world matching China's 2030 pledge boosted the prediction to just 1.1 percent.

But there is still reason for optimism. Any attempt to gaze into a crystal ball could be shortsighted. To start, the China-U.S. announcement could spur market changes and drive investment in clean energy that ultimately make it easier for other nations, or even China and the U.S., to ramp up their climate commitments. For now, the picture is incomplete at best.

"At this stage I don't think we can definitively say we have overshot the 2 degree target. It's possible that five years from now nations will realize that they can go further and faster when it comes to the initial targets," said Pete Ogden, a senior fellow and director of international energy and climate policy at the left-leaning Center for American Progress.

How is the U.S. going to achieve the cuts?

As with the rest of the administration's climate work, the cuts will be made by bypassing Congress altogether, leaning on the administration's existing authority under the Clean Air Act. The EPA's regulations on new and existing power plantswhich will slash 30 percent of the sector's emissions by 2030will no doubt account for a bulk of the emissions cuts along with fuel-efficiency standards for cars and trucks. The Department of Energy has also pledged to cut 3 billion metric tons of carbon pollution by 2030 through energy conservation and efficiency standards.

That the domestic targets will be largely met through programs already underway by the administration is hardly surprising, given the less-than-enthusiastic response from congressional Republicans to the deal. And although it would require a faster rate of emission cuts—up to between 2.3 and 2.8 percent a year between 2020 and 2025—some greens have been left unimpressed by what they see as an expected target.

Kevin Kennedy, director of the U.S. Climate Initiative for the World Resources Institute, said that the policies were the headline, rather than a specific target.

"In a sense, achieving this 2025 goal is less important than if in 2025 we're approaching more clean energy or just flattening out," Kennedy said. "If this is the end of the story, then it's not enough. But the fact that both countries have set targets they can achieve "¦ is a good starting point."

Bob Perciasepe, the former deputy administrator for EPA who helped oversee much of the president's climate plan, said it made sense for negotiators to build on that "foundation," which could snowball to put a cleaner economy in place.

"The EPA Clean Power Plan has the advantage of leaning into the natural tendency of states to innovate," he said. "That effect is likely to be increased over the next decade, so you're building up confidence. Hopefully over the next decade you can come back to Congress and get an agreement that's not based on something abstract, but based on what's happening."

EPA and DOE action alone won't account for the emissions goals, and details released by the White House don't offer much in the way of specifics for making up the difference. The two countries will expand work on carbon-capture projects in China, with plans for a project the White House says will "demonstrate a new frontier" on carbon use by eventually sequestering a million tons of CO2 and producing 1.4 million cubic meters of freshwater per year.

The countries will also expand clean-energy development, work towards green cities, focus on the trade of green goods, and enhance agreements on pollution-intensive HFCs.

What does this mean for other countries?

China and the U.S. collectively account for roughly 40 percent of the world's emissions, but what about other major polluters? Countries will meet next year in Paris with the hope of setting a legally-binding climate agreement, a discussion that has been kicked up a notch by having the two largest emitters reach an early deal.

The European Union last month negotiated a plan to cut carbon emissions by 40 percent of 1990 levels by 2030.

But now eyes are increasingly turning to India, the world's third-largest carbon polluter. And so far, the indications have not been promising for significant action.

In September, India's environment minister said the country would not offer up a pledge to cut carbon ahead of the 2015 Paris climate talks, saying that the government's focus is on addressing poverty. And the government has so far been silent on the China deal.

Jake Schmidt, international program director for the Natural Resources Defense Council, said it was unlikely India's position would change, although he was optimistic that officials would build on previous discussions with the U.S. on expanding renewable energy or boosting efficiency (both goals of Prime Minister Narendra Modi).

"Counties sitting on the sidelines should really see this as a wake-up call," Schmidt said. "The timing sends a pretty powerful signal that they need to come forward."

Kennedy said that with so much time ahead of the U.N. talks, there was plenty of room for even stronger targets as more countries came to the table. "What we want to see is this being the start of a race to the top from here to Paris," he said. "This can spiral out and show countries that this is a thing that's doable."

How have other countries done on their goals?

It's easy to set targets. It's hard to achieve them.

The U.S.-China agreement has ushered in a wave of enthusiasm for pledges that stretch beyond 2020, but a number of developing nations are already struggling to meet previously agreed-upon climate commitments.

Japan scaled back its 2020 emissions target last year after it shut down nuclear power plants in the wake of the Fukushima nuclear disaster and began relying more heavily on fossil fuels.

Canada is also expected to fall far short of reaching its 2020 emissions target, in part due to booming development in the Canadian oil sands.

Meanwhile, U.S. greenhouse-gas emissions rose in 2013 after falling for nearly a decade. German emissions also increased last year in the face of nuclear-power shutdowns, despite efforts to pump up wind and solar energy in the country.

How big of a deal is this agreement?

It's historic. The agreement marks the first time China has pledged to cap its emissions within a set time frame. As the largest polluter in the world, China is an essential player in any kind of effort to tackle global warming.

"From a climate perspective, the most important goal right now is to stop global emissions from continuing to rise. That can't happen until China's emissions peak. So this is announcement is absolutely critical as a first step," said former Clinton White House official and German Marshall Fund senior fellow Paul Bledsoe.

The significance of the world's two largest polluters coming to terms on climate months ahead of the do-or-die negotiations in Paris next year is hardly lost on supporters. But digging into the numbers has left some wanting more.

Erich Pica, president of the U.S.-based Friends of the Earth, said in a statement that the targets should become "a very low floor for presidential aspirants and not a ceiling for what is possible in the United States." The target, he said, was "grounded in neither the physical reality of climate science nor the lived reality of hundreds of millions of people in developing countries whose lives and livelihoods are in jeopardy."

"Simply put, the non-binding target falls miserably short of what science, justice, and equity demand."

Does this solve global warming?

In a word, no. The deal sets the stage for nations to negotiate a global agreement on climate change next year, with the goal of keeping the climate from warming 2 degrees Celsius above pre-industrial levels—a scientific benchmark for averting dangerous climate impacts. But a number of scientists say China's pledge falls short of what is needed to hit that target.

Instead, several scientific estimates predict that China's emissions would need to peak between 2020 and 2025 to give the world a decent shot of meeting the 2-degree target.

"You often hear people say we have to act in the next 10 years. I would say we should have acted 10 years ago," said Glen Peters, a senior research fellow with the Center for International Climate and Environmental Research in Oslo. "It is really very difficult to stay below 2 degrees Celsius."

In an interview with Reuters, Rajendra Pachauri, who heads the U.N.'s Intergovernmental Panel on Climate Change (IPCC) acknowledged that the pledge alone did not follow the path to zero net emissions by 2100, the path laid out by his panel in its most recent report as necessary to avoid the worst impacts of climate change.

Cambridge researcher Chris Hope went further, saying that "statements about [the agreement's] ambition should be treated with caution." Even with the agreements, Hope's projection model only gives the world a less than 1 percent chance of staying below the 2-degree benchmark. Accounting for the developing world matching China's 2030 pledge boosted the prediction to just 1.1 percent.

But there is still reason for optimism. Any attempt to gaze into a crystal ball could be shortsighted. To start, the China-U.S. announcement could spur market changes and drive investment in clean energy that ultimately make it easier for other nations, or even China and the U.S., to ramp up their climate commitments. For now, the picture is incomplete at best.

"At this stage I don't think we can definitively say we have overshot the 2 degree target. It's possible that five years from now nations will realize that they can go further and faster when it comes to the initial targets," said Pete Ogden, a senior fellow and director of international energy and climate policy at the left-leaning Center for American Progress.

How is the U.S. going to achieve the cuts?

As with the rest of the administration's climate work, the cuts will be made by bypassing Congress altogether, leaning on the administration's existing authority under the Clean Air Act. The EPA's regulations on new and existing power plantswhich will slash 30 percent of the sector's emissions by 2030will no doubt account for a bulk of the emissions cuts along with fuel-efficiency standards for cars and trucks. The Department of Energy has also pledged to cut 3 billion metric tons of carbon pollution by 2030 through energy conservation and efficiency standards.

That the domestic targets will be largely met through programs already underway by the administration is hardly surprising, given the less-than-enthusiastic response from congressional Republicans to the deal. And although it would require a faster rate of emission cuts—up to between 2.3 and 2.8 percent a year between 2020 and 2025—some greens have been left unimpressed by what they see as an expected target.

Kevin Kennedy, director of the U.S. Climate Initiative for the World Resources Institute, said that the policies were the headline, rather than a specific target.

"In a sense, achieving this 2025 goal is less important than if in 2025 we're approaching more clean energy or just flattening out," Kennedy said. "If this is the end of the story, then it's not enough. But the fact that both countries have set targets they can achieve "¦ is a good starting point."

Bob Perciasepe, the former deputy administrator for EPA who helped oversee much of the president's climate plan, said it made sense for negotiators to build on that "foundation," which could snowball to put a cleaner economy in place.

"The EPA Clean Power Plan has the advantage of leaning into the natural tendency of states to innovate," he said. "That effect is likely to be increased over the next decade, so you're building up confidence. Hopefully over the next decade you can come back to Congress and get an agreement that's not based on something abstract, but based on what's happening."

EPA and DOE action alone won't account for the emissions goals, and details released by the White House don't offer much in the way of specifics for making up the difference. The two countries will expand work on carbon-capture projects in China, with plans for a project the White House says will "demonstrate a new frontier" on carbon use by eventually sequestering a million tons of CO2 and producing 1.4 million cubic meters of freshwater per year.

The countries will also expand clean-energy development, work towards green cities, focus on the trade of green goods, and enhance agreements on pollution-intensive HFCs.

What does this mean for other countries?

China and the U.S. collectively account for roughly 40 percent of the world's emissions, but what about other major polluters? Countries will meet next year in Paris with the hope of setting a legally-binding climate agreement, a discussion that has been kicked up a notch by having the two largest emitters reach an early deal.

The European Union last month negotiated a plan to cut carbon emissions by 40 percent of 1990 levels by 2030.

But now eyes are increasingly turning to India, the world's third-largest carbon polluter. And so far, the indications have not been promising for significant action.

In September, India's environment minister said the country would not offer up a pledge to cut carbon ahead of the 2015 Paris climate talks, saying that the government's focus is on addressing poverty. And the government has so far been silent on the China deal.

Jake Schmidt, international program director for the Natural Resources Defense Council, said it was unlikely India's position would change, although he was optimistic that officials would build on previous discussions with the U.S. on expanding renewable energy or boosting efficiency (both goals of Prime Minister Narendra Modi).

"Counties sitting on the sidelines should really see this as a wake-up call," Schmidt said. "The timing sends a pretty powerful signal that they need to come forward."

Kennedy said that with so much time ahead of the U.N. talks, there was plenty of room for even stronger targets as more countries came to the table. "What we want to see is this being the start of a race to the top from here to Paris," he said. "This can spiral out and show countries that this is a thing that's doable."

How have other countries done on their goals?

It's easy to set targets. It's hard to achieve them.

The U.S.-China agreement has ushered in a wave of enthusiasm for pledges that stretch beyond 2020, but a number of developing nations are already struggling to meet previously agreed-upon climate commitments.

Japan scaled back its 2020 emissions target last year after it shut down nuclear power plants in the wake of the Fukushima nuclear disaster and began relying more heavily on fossil fuels.

Canada is also expected to fall far short of reaching its 2020 emissions target, in part due to booming development in the Canadian oil sands.

Meanwhile, U.S. greenhouse-gas emissions rose in 2013 after falling for nearly a decade. German emissions also increased last year in the face of nuclear-power shutdowns, despite efforts to pump up wind and solar energy in the country.

This article is from the archive of our partner National Journal.

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