Non-CO2 pollutants could delay warming by decades

Posted: 29 November 2010

Led by the Federated States of Micronesia, a group of low-lying islands and other vulnerable countries are calling for fast action on the roughly half of global warming caused by pollutants other than carbon dioxide (CO2).

The scientific case for such a strategy was laid out on the eve of the UN climate negotiations in Cancun in an Op Ed in The New York Times by Professor Veerabhadran Ramanathan, from the Scripps Institution of Oceanography at the University of California, San Diego, and his colleague, Professor David Victor.

Ramanathan and Victor highlight the importance of aggressively reducing CO2 emissions, but note that the road ahead will be long, difficult, and expensive, and that “in the meantime, a fast-action plan is needed.”

The authors go on to say that reducing the non-CO2 pollutants can delay additional climate warming by several decades. Among the non-CO2 pollutants are hydrofluorocarbons (HFCs), methane, tropospheric ozone, and black carbon soot. Technology is already available to reduce these climate-forcing agents, and doing so would produce strong collateral benefits.

Smoke and soot contribute to global warming.<br> Credit: James Hansen
Smoke and soot contribute to global warming.
Credit: James Hansen

For example, reducing emissions from open cooking and diesel vehicles could save many of the 1.9 million lives lost each year due to black carbon soot. Reducing tropospheric ozone can improve public health as well as agricultural productivity. Methane is another potent climate warmer that needs to be targeted; capturing emissions from sources such as landfills and coal mines would benefit the climate system and the gas could then be used as a source of energy.

Micronesia submitted a proposal last year to address these very climate warmers – black carbon, methane, and tropospheric ozone – under the UN climate treaty. Micronesia re-submitted their “Programme of Work on Opportunities for Near-Term Climate Mitigation” this year and it will be considered by Parties at the Cancun meetings over the next two weeks.

“This is a critical opportunity that all of the Parties in Cancun need to be aware of now,” said Durwood Zaelke, President of the Institute for Governance & Sustainable Development, whose group supports action on non-CO2 and will be attending the Cancun meetings. “CO2 is the main game, but it’s pretty clear that progress on CO2 is not going to be quick or easy, and we still need to do something fast on climate to buy time – this is what reducing non-CO2 emissions can do for the world.”

In addition to the Micronesia’s proposal on near-term mitigation, there is another major opportunity for climate progress in Cancun: phasing down HFCs under the Montreal Protocol ozone treaty. This has been a parallel effort of Micronesia’s for the last few years under the ozone regime, where HFCs are the current substitute for substances that deplete the ozone layer. The U.S., Canada, and Mexico provided their support for this strategy through a separate, but similar “North American” proposal.

At the treaty’s meeting earlier this month in Bangkok, 91 countries signed onto a declaration supporting the use of low-global warming potential substitutes instead of HFCs which can have hundreds to thousands the warming potential of CO2. The Parties included Micronesia and other small island nations, the Philippines, Indonesia, Bangladesh, Egypt, Congo, Nigeria, the 27 countries of the EU, as well as Japan, the U.S., Canada, and Mexico.

The Parties in Cancun can ensure success with this effort – and win a major climate prize of up to100 billion tonnes of carbon dioxide-equivalent in mitigation – by directing the Montreal Protocol to take responsibility for production and use of HFCs (emissions are controlled by the Kyoto Protocol).

“Fast action on HFCs and the other near-term climate warmers is essential for the survival of low-lying islands and other vulnerable States,” said Andrew Yatilman, Director of Micronesia’s Office of Environment and Emergency Management. “This is the time for action and we can do it now, right here in Cancun.”