So this is global warming?

Snow conceals hard choices

A week ago The Independent reported that 1996 had been one of the world's warmest years on record, adding to scientists' convictions that man-made climatic change was well under way.

Ever since then, across Europe, it has got colder and colder. In cosy pubs across the country the lounge-bar talk has been: ``Whatever happened to global warming?''

It is a tough but fair question. In a world still prone to spells of extreme cold which kill scores of people and cost hundreds of millions of pounds, how can electorates and politicians be convinced that global warming matters?

It has been a front-runner among green issues for almost a decade. World leaders - Clinton, Kohl, Thatcher, Major - have all made solemn speeches declaring that something must be done. But very little has been done. The new politics and diplomacy of weather and climate amount to little more than hot air.

We are curious, awed by the notion that a single species - us - can now alter our planet's entire climate. But in a bitter week of frozen winds from Siberia, it is hard to think of this grand, looming threat as anything other than an apocalyptic fantasy or an irrelevance.

But global warming is happening, it does matter, and we should take action now to reduce the threat. There is a golden opportunity to do so later this year. In December in Japan, environment ministers from around the world will meet in order to strengthen the very weak global warming treaty which was signed at the Rio Earth Summit in 1992.

Under that treaty, developed countries undertook to stabilise their rising annual emissions of heat-trapping "greenhouse gases" at the 1990 level by 2000. Most of them - but not Britain - seem set to break that promise.

What is now required at the Japan meeting is a treaty commitment from the developed countries - which have produced the great bulk of the atmospheric pollution to date - to reduce their emissions. That means using less coal, oil and gas. Burning these fossil fuels adds carbon dioxide and other greenhouse gases to the atmosphere.

And that, in turn, means increasing taxes on these fuels. But electorates and politicians hate the idea. The debacle over raising VAT on domestic electricity and gas, the griping about increased petrol and diesel duty which inevitably follow each UK Budget, the gutting of the first Clinton administration's energy tax, shows just how much.

Reducing emissions also requires giving householders, commerce and industry other, more popular incentives to conserve energy, which could in turn be funded by those larger fuel and power taxes. The expansion of non-polluting energy sources needs to be intelligently subsidised.

But back to today's bitter cold. Why should voters and politicians even believe in global warming - let alone make changes to their habits, homes and economies - with fresh memories of freezing weather?

They need to get the message that the climate will retain its natural variability, with continued extremes of hot and cold, drought and flood, against the background of a gradual, world-wide warming trend.

As we reported last week, scientists at the Meteorological Office's Hadley Centre for Climate Prediction have found that average annual world temperatures are now 0.6C higher than they were a century ago.

The science of global warming has made giant strides in the past 10 years. There is now a consensus among climatologists that the warming trend will continue and, in all probability, accelerate into the next century. It will be the fastest rate of change since the last Ice Age ended 10,000 years ago.

There will be cooler years, even cooler decades, which buck the trend, because natural variability will continue. By changing prevailing winds and ocean currents, some countries could even end up colder.

Rich countries like Britain may find it fairly cheap and easy to adapt to whatever climate change we experience here. Some recent studies have suggested that the US, Canada and Russia, which have done more in total or in per capita terms to raise the concentrations of greenhouse gases than other nations, may actually benefit from climate change in the next century.

But poor, populous ones, such as Bangladesh, will find the shifts in temperature and rainfall, and the rising sea levels, much harder to cope with and possibly catastrophic.

Common sense and justice demand that the developed countries do act. Short-termism and selfishness make it quite likely that they will not. But they have been warned.