It seems to have gone virtually unnoticed, but the world leaders at the weekend's G8 summit look as if they have taken the biggest step in years in tackling climate change. And it's quite apart from anything to do with carbon dioxide.

The summit's final communiqué, the Camp David Declaration, supports “comprehensive actions” to reduce “short-lived climate pollutants”. These substances – including black carbon (soot), methane, ground-level ozone, and hydrofluorocarbons – are responsible for about half of global warming. Straightforward measures to address them, a report by the United Nations Environment Programme concluded last year, would delay dangerous climate change by more than three decades, buying crucial time for the much more difficult process of slashing carbon dioxide emissions.

More important still, the measures would save some 2.4 million lives a year, mainly by cutting the inhalation of soot, chiefly emitted by vehicle diesel engines and by the inefficient wood and dung burning cookstoves used by most of the world's poorest people – and increase grain harvests, at present hit by pollution, by 52 million tons a year.
While the international climate negotiations drag on, these pollutants can be reduced through existing national laws and regulations, using technologies that are already available. And many climate sceptics agree on the importance of doing so: Senator James Inhofe, who pioneered Republican rejection of action to curb carbon dioxide, supports it on black carbon, while Canada – which caused controversy this winter by quitting the Kyoto Protocol – has been in the forefront of countries urging an assault on such the short-lived agents of climate change.

The G8's endorsement of action at the weekend is a triumph for the small Institute for Governance and Sustainable Development (IGSD), which has been campaigning for action on the pollutants while most climate scientists and green pressure groups have ignored them. In just a few short years it has brought the issue from invisibility to the agendas of the world's most powerful leaders. In February six governments – including the US, Canada and Mexico – launched a five year programme to tackle them, and the rest of the G8 has now signed up to it. And it commissioned the World Bank to produce a report on how it can integrate ways of reducing them into its activities.

The leaders also reaffirmed their commitments to limiting the increase in the world's temperature to less than two degrees centigrade over pre-industrial levels and phasing out subsidies for fossil fuels – and welcomed December's Durban climate summit as “a significant breakthrough” towards reaching international agreements on cutting carbon dioxide by 2015.

It will remain important to continue this international effort. But as Durwood Zaelke, the IGSD president puts it “the solution-orientated approach” of the programme to address the short-lived pollutants can “show the world it is possible to start meeting the climate challenge.”