I'm writing on one of the hottest days on record in Britain, and we're not the only ones sweltering. The latest heatwave is causing mayhem in 30 countries across the northern hemisphere and follows the hottest decade globally on record. It is further proof of global warming. Climatologists are increasingly sure that the cause is man-made, through emissions of carbon dioxide and other greenhouse gases from burning fossil fuels.
Climate change poses a threat as great as WMDs. Floods, droughts and violent storms are increasing in frequency and intensity. The atmosphere is fast approaching the limit of its capacity to absorb pollution without catastrophic consequences. Rich nations are the main culprits, but the poor countries suffer the worst effects.
Under the Kyoto Protocol, industrial nations agreed to make modest cuts in greenhouse gas emissions by 2012. It was an important first step but will not halt climate change. Even if implemented in full, it delivers only a 1 or 2 per cent cut in emissions from industrial nations. Meanwhile, total global emissions will have risen by 70 per cent. Russia has yet to ratify. Australia negotiated an increase in emissions, then opted out. The US, responsible for a quarter of global greenhouse gas emissions, has refused to sign up.
Kyoto requires a review of the adequacy of existing commitments by the end of 2005. More of the same approach will not deliver the required reductions in emissions. Instead, the next climate change agreement should be based on science and social justice, "contraction" towards a safe level of emissions and "convergence" towards equal per capita emissions rights. Under this framework, rich nations would be required to make progressive cuts in emissions, while poor nations would be allowed to increase their emissions and trade surplus emissions rights. It's a fair compromise between recognising that rich nations need time to adjust and that poor nations have a right to develop.
The British government's white paper on energy, published in February, made a commitment to put the economy on a path to reduce UK carbon dioxide emissions by 60 per cent by 2050. But it now looks as if a 60 per cent cut may not be enough. Recent research has suggested that, as the temperature rises, soil microbes work faster, releasing stored carbon into the atmosphere. Such feedback effects could mean that more drastic cuts in emissions are needed.
The new evidence should add urgency to the actions of the UK government. Global climate policy is a central issue for all social democrats, not just because of the scale of the environmental challenge, but also because of the equity implications. It offers an opportunity to start defining what global social democracy looks like in practice. When Britain holds the EU presidency in the second half of 2005 - the deadline for deciding what happens after Kyoto expires - the government must rise to the challenge.
Tony Grayling is an associate director of the Institute for Public Policy Research. New Economy: beyond Kyoto, edited by Tony Grayling, can be ordered from Blackwell (01865 244 083)