Cool climate, clean planet: Research suggests cooling action will clean air

But there's good news hidden in the bad. If we take action to cool the planet, we can also expect the added benefit of cleaner air, particularly in China, says Professor Edgar Hertwich, from the Norwegian University of Science and Technology. Hertwich was one of the lead authors of the Energy Systems chapter.

"One of the main causes of greenhouse gas emissions is coal power," Hertwich says. "Coal-fired power plants produce a lot of pollution, so any measures that will reduce our combustion of coal will also help us to fight air pollution."

This will be particularly important for China, he said, which has been plagued by skyrocketing air pollution from coal power plants used to fuel its industrial expansion. Experts estimate that a quarter of a million people die prematurely each year in China because of air pollution from the country's coal-fired power plants.

Hertwich, director of NTNU's Industrial Ecology program, was one of four lead authors of the IPCC report from Norway, along with his Industrial Ecology colleague Professor Daniel Beat Müller. Müller was a lead author for the chapter on Human Settlements, Infrastructure and Spatial Planning.

Five pages, 500 comments

Hertwich's contribution as one of the lead authors of the Energy Systems chapter amounts to roughly 5 pages.

Behind those pages lie countless hours of meetings on several continents, thousands of email exchanges and two levels of "peer review," by other scientists and interested parties as well as 24 governments, where Hertwich's work garnered more than 500 comments, each of which had to be addressed.

Hertwich's contribution is a window on the huge effort that goes into producing the IPCC reports, a part of price that must be paid to help the world change its ways. And as an industrial ecologist like Hertwich will tell you, price is everything in determining the kinds of choices we will make to either protect the planet's climate -- or irreversibly change it.

As head of NTNU's Industrial Ecology program, and with all of his public contributions to efforts like the IPCC, Hertwich's mission is to help people clearly see the costs and consequences of their actions so they can make the best decisions possible. And in doing so, save the planet.

A menu for action

In its own words, the Intergovernmental Panel on Climate Change (IPCC) "is the leading international body for the assessment of climate change." Created by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) in 1988, the group has released four assessment reports that present ever more sobering appraisals of what humankind is doing to the climate by burning fossil fuels and releasing greenhouse gases to the atmosphere.

The Fifth Assessment Report is being released in pieces, with the report of the Working Group II on "Impacts, Adaptation and Vulnerability" released at the end of March. Working Group III, whose report was released on 13 April, has been charged with studying options for mitigating the negative impacts of climate change.

The Working Group III report is different from the other IPCC reports because it gives the world an overview -- a menu, if you will -- of all of the tools at hand needed to tackle what is undoubtedly the most difficult problem ever to face humankind.

Urgent need to cut emissions

Although Hertwich is relentlessly upbeat about our ability to tackle climate change, he is nevertheless quick to point out that the past decade has seen an unprecedented rate of increase in greenhouse gas concentrations in the atmosphere as a result of a global rise in emissions.

The world is now at the very upper end of the emissions scenarios presented in previous IPCC reports, Hertwich says, which gives new urgency to the need to act.

"There is a clear concern about what we call the carbon budget," he says. The world's scientists have calculated a carbon budget for the planet, which tells us how much CO2 we can put into the atmosphere before we reach concentrations above which we will unacceptably warm the planet. If we continue to emit greenhouse gases at current rates, we risk "overshooting" the carbon budget, with dire consequences.

"We understand now if we do not want to overshoot, we need to bring emissions down to basically zero over the next 50-60 years," he said.

If humankind does not control the growth in greenhouse gas emissions in the next decade, it increases the likelihood that we will need "negative-emissions technologies," such as bioenergy with CO2 capture and storage or CO₂ removal from the atmosphere, he said.

"These are unproven and expensive technologies that will shoulder future generations with substantial costs," he said.

Renewables are coming on line

But there's good news, too, at least when it comes to energy sources, Hertwich said. The world is making significant investments in renewable energy, which in turn is making renewables cheaper and easier to bring to market.

"What I found was really surprising was the rate at which renewable power has come on line," Hertwich said.

He noted that the last IPCC report was published in 2007, when solar power was more of a novelty source of energy for individuals who were too far from power lines to get conventional electricity from the grid.

"Today we build large power plants that can supply entire cities with renewable electricity. In fact, today we install the equivalent of 100 large coal-fired power plants -- the same capacity in renewables -- every year," he said. However, "we haven't started phasing out the coal-fired power plants, so this needs to happen, too."

The good news is that the WG III report presents a full range of options for action. But more importantly, policy makers and the general public will have to take this information and decide what to do about it, he says.

"I don't think reports by themselves can make a difference," Hertwich said. "The report itself is not the cause of change, but it can contribute to helping people make the right choices when they are actually willing to change something."

A link to the report can be found at: http://www.ipcc.ch/report/ar5/wg3/