Even Robert Zoellick remembers when climate change was a forbidden phrase at the World Bank.

Those days, though, are long gone. The World Bank now has a special envoy for global warming. In recent years, the institution committed billions of dollars to clean energy, sustainable transportation and protecting vulnerable countries from the impacts of global warming. Finding ways to address the looming catastrophes promised by man-made climate change is now front and center on thousands of top-level World Bank reports, memos and policy briefs.

As Zoellick prepares to step down Friday after five years as World Bank president, many credit him with driving important changes on climate action during his tenure. Others say he merely went along for the ride as climate change became a hot topic on the world stage -- failing, meanwhile, to move the bank significantly on its most entrenched issue, coal.

Robert Zoellick. Photo by Jeremy Tripp, courtesy of the Peterson Institute for International Economics.

For his part, Zoellick describes himself as an agent of change on climate. At a recent discussion at the Peterson Institute for International Economics -- where, along with Harvard University, Zoellick plans to split his time after his World Bank term ends -- he described his approach on global warming as one of practical consensus-building.

"We're trying to make things happen on the ground, and the more we do that, the more support we can build. When I came to the bank -- I don't want to overstate this; [former president] Jim Wolfensohn made some very good progress -- but the environmental community was still quite suspicious.

"As I leave the bank, I've got them coming in and wanting us to do more in oceans and various animal species groups that we've tried to help, and that's an encouraging sign," he said. "That's what you want to have."

Bird watcher and 'adding machine'

A Harvard-trained lawyer, Zoellick is widely described as a pragmatist and a towering intellect whom former President George W. Bush nicknamed "the adding machine" on the campaign trail for his number-crunching skills. An avid bird watcher and conservationist who keeps paintings of tigers and a map depicting their shrinking habitats in his office, Zoellick previously served on the national council of the World Wildlife Fund.

He came to the World Bank with some expertise on climate politics. Under former President George H.W. Bush, Zoellick supported the creation of the Global Environment Facility and steered U.S. policy for the first Rio Earth Summit in 1992 that led to the U.N. Framework Convention on Climate Change. He opposed the Kyoto Protocol, saying recently, "I didn't think it would work." But as deputy secretary of the State Department under George W. Bush, he spearheaded an Asia-Pacific partnership to develop, deploy and transfer clean technology to poor countries.

When Zoellick arrived in July of 2007, he entered an institution where morale had been badly damaged, particularly among environmental advocates. The previous president, Paul Wolfowitz, had been known to personally intervene to remove the words "climate change" from bank progress reports, substituting it with "clean energy" a phrase presumably more acceptable to the George W. Bush White House.

"Wolfowitz wasn't there for very long, but you could not use the words 'climate change.' It was expunged from reports. People were working on it, but it was underground," said Michelle de Nevers, a senior program associate at the Center for Global Development think tank and former senior manager of the World Bank's environment department.

When Zoellick arrived, she said, "People were afraid to resuscitate the agenda because he was still a Republican and it was the Bush administration." Yet to the surprise of many, Zoellick's maiden speech at the World Bank focused not on trade, as most believed the former U.S. trade representative would, but on climate. He made specific commitments, including to step up financial assistance for climate change and outlining ways the World Bank can "integrate the needs of development on low-carbon growth."

Later that year, he attended the U.N. climate conference in Bali, Indonesia. It didn't go well for the George W. Bush administration -- American negotiators were booed for holding out on the adoption the "Bali Roadmap," and de Nevers recalls that a panel that Zoellick sat on was something of a flop. Yet by all accounts, Zoellick returned home energized. He launched the "Bali Breakfasts," early morning sessions at the World Bank spring meetings to bring finance ministers into the conversation on global warming. For some, it was the first time that ministers who held their nation's purse strings engaged on climate change.

Coping with consensus

"That's when he got really, really engaged. He wanted to get climate change on the agenda of finance ministers, and that was a really important thing to do," de Nevers said. That was followed on its heels by the creation of the forest carbon partnership facility and the climate investment funds that have generated $7.2 billion to help at least 50 countries develop clean energy and prepare for climate impacts. In 2010, he appointed Andrew Steer to be the bank's first-ever climate change envoy.

"I would say that he elevated climate change at the World Bank, and in doing so made it a better poverty-fighting institution," said William Reilly, former U.S. EPA administrator under President George H.W. Bush. "He didn't succeed at everything, but he was good about mobilizing new financial resources for climate change, making that quite a big development sector."

The most glaring area in which Zoellick did not succeed, analysts agree, is coal. Under his tenure, the World Bank approved a 4,800-megawatt power plant in South Africa that will spew about 25 million metric tons of greenhouse gas emissions. Another coal plant in Kosovo is waiting in the wings. And an energy lending blueprint that calls for the World Bank to phase out coal loans to middle-income countries is in permanent limbo, held up by developing countries that refuse to be constrained.

World Bank officials point out that the institution runs on consensus, and the management -- even the president -- must serve its client country's needs. Bank critics, meanwhile, argue that Zoellick never tried to lead the board on coal. While the bank under Zoellick brought in renewable energy expert Daniel Kammen to lead the energy strategy, management failed to give him a team. Meanwhile, critics say Zoellick showed no backbone or even interest in fighting for that strategy before the board.

"He just wasn't willing to stick his neck out on the energy strategy," said Justin Guay, coal campaigner with the Sierra Club. And while he acknowledged the bank has dramatically ramped up funding for clean energy, he argued that legacy is tainted by its continued embrace of fossil fuels.

"It's a huge failure of leadership," Guay said. "What the World Bank does with its dollars says less than what they say with their policy."

'Very practical realist'

Andrew Deutz, director of international government relations at the Nature Conservancy, took an accounting approach to summing up Zoellick's climate legacy.

"I think it helps to look at this tenure on climate change as a ledger, and there are more positive things than negative things on the ledger," he said. "Overall, he's definitely pushing the bank in the right direction."

Those who have worked with Zoellick say his evolution on coal was gradual and see in his approach to the coal fight signs of the consummate negotiator.

Jennifer Haverkamp, international counsel at the Environmental Defense Fund, who served as assistant U.S. trade representative for the environment under Zoellick, recalled that when faced with the hot-button issue of access to medicines, Zoellick was able to find compromise by reaching out one on one with others seeking common ground.

"He likes to find solutions and work away at problems and solve them," Haverkamp said. Others say that is the approach Zoellick has taken to energy, choosing to focus on areas where developing countries can agree -- like the need to develop low-carbon growth strategies -- rather than divisive issues like coal lending.

Reilly called Zoellick "a very practical realist," and "an inside operator," adding that on the energy strategy, as with other issues, Zoellick "had a relatively subdued way of affecting things. He was more of someone who leads from the negotiating table than using the bully pulpit. ... I've never seen him make a call to action."

Yet a call to action is precisely what environmental groups are hoping to see from the incoming president, Jim Yong Kim. In addition to eliminating loans for coal, activists say they would like to see the World Bank create a unit devoted to working on ways to deliver renewable energy to the world's 1.6 billion people currently living without access to power.

In the future, Haverkamp said, "The bank needs to be extremely strategic in how it invests scarce public resources. The bank needs to put a lot of distance between its future and its history of helping to finance large fossil fuel plants."