You might think that a little climate change would not go amiss in the British Isles. We’d have more warm summers and fewer freezing winters. What’s wrong with that?

Ask the people of Yorkshire. As a result of global warming, many homeowners this week are up to their waists inmuddy water. Andflooding could be just the beginning of our worries. This week a paper in the British Medical Journal gave warning that climate change could be particularly damaging to the health of people in the developing world, but research also suggests that it could be bad news for Britain. Delegates at a conference in London on Tuesday will be told that global warming will drive up rates of cardio-respiratory disease, diarrhoea and insect-borne diseases such as malaria in the UK.

Global warming is believed to be occurring because human activities, particularly burning fossil fuels, have released into the atmosphere huge amounts of carbon dioxide and other “greenhouse gases” that are trapping more heat in the Earth’s lower atmosphere. Average global surface temperatures are already rising and are predicted to increase by between 1.4C and 5.8C over the next century, bringing a higher risk of floods, droughts and heat waves.

“We are already witnessing the effects of climate change on health,” says Dr Hugh Montgomery, the director of the Institute for Human Health and Performance at University College London, who has organised next week’s conference at the Royal College of Physicians. The heat wave of 2003, when temperatures in the northern hemisphere reached the highest on record, killed up to 35,000 people – 2,000 of them in the UK. Last summer’s floods have been shown to increase rates of mental illness (see box, left). And milder weather is likely to be behind the arrival here from Europe of the midge-borne cattle disease bluetongue.

“Each of us is, in effect, moving 6km (4 miles) south a year or 60km a decade,” says Dr Montgomery. “The result will be fewer deaths from colds and flu, but more from strokes and heart attacks because of the heat. Global warming means a higher baseline temperature from which there will be more surges and extreme events.”

Every one degree rise means 75 deaths

By the 2080s we can expect to see weather like that of August 2003 every year. This is bad news. Studies by the Department of Health have shown that in June 2006, when temperatures in the UK soared, there were 75 extra deaths for every one degree rise on the thermometer, with children, older people, those living in built-up areas and the chronically sick most at risk. Deaths can be caused by the body’s inability to adapt and cool itself sufficiently. However, the main causes of death and illness are cardiovascular and respiratory disease.

When it’s hot, large quantities of blood are circulated to the skin to keep it cool, placing a sometimes catastrophic strain on the heart. In addition, heat causes ozone concentrations and pollution levels to rise. This increases asthma rates and causes extra deaths from a range of respiratory illnesses.

The heat is also likely to bring more unwelcome insects to these shores. While it is unlikely that malaria will take hold – the disease is controllable in countries with good healthcare – other disease-carrying insects (known as vectors by scientists) may arrive.

“Climate change poses a significant risk of the introduction of vector-borne diseases into Europe and indeed there is evidence that such change has already happened,” says Paul Hunter, a professor of health protection at the University of East Anglia. “Several vector-borne diseases not previously described in Europe have appeared, including chikungunya [a virus carried by Asian tiger mosquito that causes fever, headache and joint pain]. There was an outbreak in Italy last summer.”

Warmer, drier weather could change our landscape, too. Professor Ian Crute, the director of the Biotechnology and Biological Sciences Research Council’s Rothamsted Unit, predicts more maize grown, a possible regeneration of the tree fruit industry and the movement of greenhouse-grown fruit and vegetables to the north. “But I don’t expect we’ll ever have acres of sunflower fields or olive groves,” he says.

However, climate change will have a big impact on the way we live. “Events like the drought that has caused Australian wheat crop failure – and affected worldwide wheat prices – will become common. The era of cheap food that we have enjoyed since the Second World War is ending and people on low incomes will find it increasingly difficult to eat a healthy diet.”

What can we do about it?

Failure to act could have catastrophic consequences but striving to cut carbon emissions could produce unexpected benefits. “What we do to deal with climate change could bring about a revolution in public health,” says Ian Roberts, a professor at the London School of Hygiene and Tropical Medicine. For example, reducing our dependence on cars should mean that more people walk and cycle, leading to a decrease in obesity. It should also reduce road accidents, which kill more than 3,000 Britons a year.

“At the moment we are in a vicious cycle,” says Professor Roberts. “We use our cars more and get fatter because we are not exercising. As we get heavier, we become more dependent on fossil fuels because we are reluctant to walk or cycle at all. We need to break this loop.

“If we design climate change policy to max-imise the health benefits, it will be the silver lining to the cloud of global warming. It’s the only bit of good news in the whole story.”

Rising woes

Increased risk to our physical health won’t be the only result of climate change, our mental health may also be affected.

Sara Wolcott* and family were among the 1,950 people made homeless by floods last July in Gloucestershire (see picture above). “After two months, I had panic attacks when my two sons or my husband left me alone. I kept thinking about all the things we’d lost, reliving it over and over,” she says.

Wolcott, who saw her GP and was prescribed antidepressants, isn’t alone. Soon after the floods, Gloucestershire Primary Care Trust (PCT) had an increase in reports of mental health problems. In response, it set up the People Recovery Group to help those suffering stress and anxiety.

“There is evidence that disasters can increase incidence of mental health problems,” says Dr Nevila Kallfa, of Gloucestershire PCT. “People are living not just with the loss of their homes and posessions but with the constant fear that it will happen again.”

Wolcott agrees: “If floods become the norm, it would add an extra level of stress that’s bound to affect people’s health.” - LAURA DEELEY

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