This post originally appeared at Sciblogs.co.nz.
This year has seen outbreaks of extreme weather in many regions of the world. No one can say with certainty that events such as the flooding in Pakistan, the unprecedented weather episodes in some parts of the US, the heatwave and drought in Russia, or the floods and landslides in northern China were influenced by climate change. Yet they constitute a stark warning. Extreme weather events will grow in frequency and intensity as the world warms.
No binding agreements were reached at the meetings in Copenhagen last December. Leaked emails between scientists at the University of East Anglia, claimed by critics to show manipulation of data, received a great deal of attention - as did errors found in the volumes produced by the UN's Intergovernmental Panel on Climate Change. Many newspapers, especially on the political right, have carried headlines that global warming has either stopped or is no longer a problem.
It cannot be emphasised too strongly that the core scientific findings about human-induced climate change and the dangers it poses for our collective future remain intact.
The most important relevant fact is based on uncontroversial measurements: the carbon dioxide concentration in the atmosphere is higher than it has been for at least the last half-million years. It has risen by 30 per cent since the start of the industrial era, mainly because of the burning of fossil fuels.
If the world continues to depend on fossil fuels to the extent it does today, carbon dioxide will reach double pre-industrial levels within the next half-century. This build-up is triggering long-term warming, the physical reasons for which are well-known and demonstrable in the laboratory.
Data from the US National Oceanic and Atmospheric Administration show that this year is set to be the warmest year globally since their records began in 1880. June was the 304th consecutive month with a land and ocean temperature above the 20th-century average. Last year, the administration analysed findings from some 50 independent records monitoring temperature change, involving 10 separate indices. All 10 indicators showed a clear pattern of warming over the past half-century.
A renewed drive is demanded to wake the world from its torpor. The catastrophic events noted above should provide the stimulus. The floods in Pakistan have left some 20 million people homeless. Pakistan cannot be left to founder - but neither can other poor countries, many of which are vulnerable to catastrophic weather events.
World leaders should expedite and accelerate the discussions currently under way to provide large-scale funding for poorer countries to develop the infrastructure to cope with future weather shocks.
The United States and China are far and away the biggest polluters in the world, contributing well over 40 per cent of total global emissions. The European Union is pursuing progressive policies in containing the carbon emissions of its member states. Yet whatever the EU and the rest of the world do, if the US and China do not alter their current policies there is little or no hope of containing climate change.
The US has 4 per cent of the world's population but churns out 25 per cent of the world's carbon emissions. It must assume a greater leadership role in world efforts to curb climate change. President Barack Obama should reassert that containing climate change is one of the highest priorities of his administration.
Positive initiatives are happening at the level of local communities, third-sector organisations, cities and states. These groups must exert pressure on many different levels to promote a significant reduction in emissions across the whole US.
China's leaders show increasing awareness of how vulnerable their country is to climate change, and are investing in renewable technologies and nuclear power on a substantial scale. However, China's carbon emissions are steadily increasing. It has the right and the need to develop, but much clearer plans than seem to exist at present are needed to show how the country intends to move away from its existing high-carbon path. The Chinese leadership should formulate such plans, make them public and open them up for international scrutiny.
The current emphasis on improving energy efficiency is important, but nowhere near enough to seriously chart such a path.
Russia is the third-largest emitter of greenhouse gases. President Dmitry Medvedev has proposed targets the country should adopt, but as they stand they are empty. Calculated against a 1990 baseline, they are accounted for simply by the decline of the country's uncompetitive heavy industries.
Above all, a renewed impetus to international collaboration is required. The meetings of the UN to be held at Cancun in December carry little promise of initiating policies on the scale needed. The US, China, the EU and other major states such as Brazil and India, with due attention paid to the interests of smaller nations, should work with a greater sense of urgency.
Giddens is a former director of the London School of Economics, a fellow of King's College, Cambridge and the author of The Politics of Climate Change. Rees is president of the Royal Society of London.
This post originally appeared at Sciblogs.co.nz.