The resurgence of El Niño means that 2010 could yet be the hottest year on record

Despite the big freeze Britain's climate is getting distinctly warmer – and we may feel it this summer
Robin McKie, The Observer 10 Jan 10;

It may be a hard notion to accept after a week that has seen the nation paralysed by snow and ice. Nevertheless, meteorologists are adamant that our world is still getting warmer. Indeed, many now believe that 2010 may turn out to be the hottest year on record.

Britain may be shivering, the Met Office may have issued emergency weather warnings for the entire country and hundreds of trains and flights may have been cancelled, but our future is destined to be a hot and sticky one. And we are likely to feel the consequences sooner rather than later.

It is a point stressed by Doug Smith, a climate expert at the Met Office. "The hottest year on record was 1998 and some people have argued that if global warming is really taking place, we should have had an even warmer year since then. We haven't, I admit. And yes, the weather is absolutely terrible at present. However, I am sure things will change – and we won't have to wait long either."

Smith and other meteorologists say that for the past few years, temperatures have been prevented from soaring even higher than they did in 1998 thanks to one key factor: the El Niño warming of the Pacific. This phenomenon occurs at irregular intervals of between two and seven years and can last for months, pumping vast amounts of heat into the atmosphere. A strong El Niño occurred in 1998 and played a key role in heating the world to a record-breaking level. (El Niño is Spanish for "the boy", a reference to the birth of Christ, which relates to the fact that this warming period typically begins around Christmas.)

In recent years, however, the Pacific has cooled thanks to a corresponding ocean phenomenon, known as La Niña (Spanish for "the girl"). It depresses sea surface temperatures and has played a key role in limiting global warming since the turn of the century. As a result, global temperatures have been prevented from rising above their 1998 record level. That cooling has now stopped, however, and a new El Niño warming period has just started in the Pacific.

"If that keeps up for the next few months, it will result in a great deal of heat being pumped into the atmosphere," added Smith. "The signs are that it will. If so, our computer models indicate that this year is more likely than not to be the hottest on record. Even if it isn't, I am quite sure a record breaker will still occur in the next few years."

The headlines then will look very different from the "Britain in deep freeze" variety that have appeared over the past few days, though we should note a key caveat here. Soaring global temperatures do not guarantee hot weather for Britain. We may still get a poor summer, but that does not mean the world is not continuing to heat up, a point ignored by most climate-change deniers.

In fact, there is a world of difference between the British weather at any given time and the inexorable shift that is taking place in the climate of the planet, as Peter Inness, a Reading University meteorologist, makes clear. "Britain covers only a very small part of the globe. It takes up less than one thousandth of the world's surface. The temperature here is almost irrelevant when considering the issue of global climate change."

It is a point that should be kept in mind as councils struggle to grit roads, cars and vans slither on the ice, exams are disrupted, and farmers battle to get food to their animals. Yes, we are feeling the cold but many other parts of the world are having no such problem, as Richard Betts, head of climate impact at the Met Office, argues.

"It is true that Britain is having a spell of extremely cold weather, as is much of northern Europe and the United States. But at the same time, Canada and the Mediterranean region are having unusually warm weather for the time of year. We shouldn't get so absorbed with what is going on in our backyard."

This argument is also made by Inness – though rather more forcibly. "I think it is really stupid to say that the current cold weather proves that climate change is not happening. Climate refers to changes in the weather patterns over a 20- to 40-year period. What is happening in Britain at present represents little more than a point on a graph."

This takes us to the heart of the matter. Meteorologists may make errors with specific long-range forecasts. (This winter was more likely to be mild than severe, they thought.) There is no doubt about the overall trend. Each year, humanity pumps billions of tonnes of carbon dioxide into the atmosphere. The inevitable result will be global warming and major, catastrophic climate change.

It is a bit like playing Pooh sticks, says Betts. "When you throw sticks off a bridge, you know they will all be swept downstream. You just don't know which one will move the fastest. It is the same with climate and the weather. We know the world is warming inexorably but we cannot say specifically which year is going to be the warmest. We can only indicate what are the general prospects of getting a record-breaking year. And despite the horrible weather at present, it is quite possible that we will get one this year."