The global economy will pump $90 trillion into infrastructure development over the next 15 years, sparking a series of investment decisions that will make or break the Earth's climate, a sweeping new study out today finds.

A choice to spend that money on low-carbon measures -- things like building more compact cities, restoring degraded land and increasing renewable energy sources -- will spark jobs and economic growth in rich and poor countries alike. The high-carbon alternative, the report warns, will lock the world into dangerous levels of climate change that will upend economies for the foreseeable future.

"The next 15 years will be critical," said former Mexican President Felipe Calderón, who chaired the Global Commission on the Economy and Climate, which produced the report.

Felipe Calderon

"It is possible to tackle climate change, and it is possible to have economic growth at the same time," Calderón said. "There is an economic way to do the right thing."

With input from two Nobel laureates, three former heads of state and dozens of other leading economists, CEOs and finance ministers, the New Climate Economy report is an effort to create an equivalent of the Intergovernmental Panel on Climate Change (IPCC) report of global warming economics. Launched this morning in New York; Beijing; Johannesburg; Addis Ababa, Ethiopia; and Oslo, Norway, the study weighs the fiscal risks and gains to keeping global average temperatures from rising beyond 2 degrees Celsius.

It comes as world leaders prepare to descend on New York for a U.N.-sponsored summit aimed at building momentum for a new international climate agreement in Paris in 2015. A deal that sees all major emitters cutting greenhouse gases will be key to driving the needed global investment in low-carbon growth, the commission argues, calling it a "powerful macroeconomic policy instrument" that will send clear signals to businesses and investors.

"We need a strong, lasting, equitable international climate agreement in Paris at the end of 2015. That's important because of the politics," said Nicholas Stern of the London School of Economics, former World Bank chief economist.

"If you want to pursue strong climate policies in one country, it helps enormously to know ... that things are going on elsewhere," he said.


Growth requires 'climate responsibility'

Specifically the report throws its weight behind a legal agreement that reduces net greenhouse gas emissions to "near zero or below" in the second half of this century. Wealthy, developed countries would make "earlier and deeper absolute cuts to their own emissions, on a path to near-complete de-carbonization of their economies by mid-century."

"They will need to provide strong examples of how good policy can drive economic growth and climate risk reduction together," the report says. Development countries, meanwhile, should be provided finance to both mitigate carbon and adapt to climate risk. But the report does not abdicate poorer countries of responsibility, noting that their emissions now exceed those of high-income nations and that slowing that growth is "essential to avoiding dangerous climate change."

The report outlines 10 measures or "transformative actions" its authors argue are essential to curb global warming, particularly over the next 15 years, when the global economy is expected to undergo what the authors call a "deep structural transformation." The global economy is expected to grow by half. Cities will welcome a billion more people.

And of the $300 trillion to $400 trillion likely to be invested in the total global economy, $90 trillion will be poured into the world's cities, land-use production and energy systems.

Implementing key policies and investments in those three systems -- from phasing out fossil fuels to stopping deforestation to ramping up energy efficiency -- could deliver at least half of the emissions cuts needed by 2030 to lower the risk of dangerous climate change, said Jeremy Oppenheim, the report's program director.

In agriculture, for example, "If we just bring back 12 percent of degraded land into agricultural production, we could feed 200 million people per year by 2030" while also reducing emissions, Oppenheim said.

The report does acknowledge that going green isn't easy and notes that despite projected job creation, some jobs -- especially in high-carbon sectors -- will be lost. "The human and economic costs of the transition should be managed through support for displaced workers, affected communities and low-income households," it argues.

But, the authors note, fully implementing the recommendations in the report could deliver cuts of 50 to 90 percent of the reductions needed to get on a 2-degree pathway. "All the measures would deliver multiple economic and social benefits, even before considering their benefits to the climate," they write.

Stern said he hopes to hear heads of state make strong pledges next week in support of a global climate action.

"Vacillation and wobbling is the enemy of investment," he said. "It would be very important if the presidents and prime ministers recognized clearly that you can combine high quality and strong growth with climate responsibility. Too often we've seen this expressed as some kind of artificial horse race between growth on the one hand and climate responsibility on the other. It's very important that the presidents and prime ministers recognize that the challenge is to combine the two."