We need to act now if we want to reduce the impact we are having on climate change. If we don't, the unpredictable weather variations we are already experiencing will become more severe.

The effects of climate change can be seen in our everyday lives. During the last 40 years, the UK's winters have grown warmer, with heavier bursts of rain. The summers are growing hotter - one of the starkest changes over the last 200 years is that our summers have become drier causing widespread water shortages.

Nine of the last ten years have been the warmest since records began, and during August 2003, the hottest temperature ever recorded in the UK was taken in Brogdale in Kent. It was 38.5°C.

Slowly but surely, much of the UK is experiencing extreme climates more associated with our European neighbours. The Thames barrier was raised three times a year during its first five years of operation. In the last few years it has been raised on average 13 times a year.

Many gardeners are finding their lawns need mowing in winter and snowdrops are blooming before Christmas, as winters grow milder; with fewer frosts, cold snaps and snowfalls. Spring is arriving earlier and autumn later - the growing season for plants in the UK has expanded by about a month since 1900.

Flooding

However, flooding is a looming threat over much of the country. Severe storms and rising seas - some 10cm higher than sea level in 1900 - are slowly eating away at our coastline. As rain falls in deluges, rivers are bursting their banks more often, with flash floods becoming more of a common occurrence. The floods experienced in the UK during the Autumn and Winter of 2000 were the worst for 270 years in some areas. This flooding cost the farming industry nearly £500 million.

What it means for us

By the end of the century, the average yearly temperature of the UK could be between 1°C and 4.5°C hotter than today, depending on how high greenhouse gas levels rise. The land will heat up faster than the sea, and the South East more than the North West. Summer and Autumn will generally heat up more than winter and spring, and as the nights turn hotter and stickier, the sort of temperatures we currently get at 7pm could be experienced at 11pm by 2100.

What we can expect

By the end of this century, we could be facing intense heatwaves reaching up to mid 40°C in some places, more like the heat in 2003 that killed thousands of people across the rest of Europe. Temperatures as high as this have probably not been experienced since the last great warm period over 100,000 years ago, at the same time that hippos roamed England.

As the summers become hotter and drier, drought could become a major threat. Anyone who lived through the long, hot summer of 1976 will remember the drought that reached crisis proportions: water rationing, building subsidence, withered crops, diseased trees, wildfires and deaths from the heat. Such scenarios could form the shape of summers to come if we don't learn to change our behaviours and take steps to prevent further climate change.

Impact on wildlife and health

The animal and plant worlds could also be thrown into turmoil. Many species that we traditionally associate with Britain may disappear, while there could be an increase in insects, with bloodsucking ticks, scorpions and poisonous spiders becoming a feature of everyday life. Needless to say, white Christmases could become a thing of the past, while the UK's green and pleasant land will become more brown and unpleasant as the climate becomes less suited to growing lawns and gardens.

The effects on health could also be profound. Aside from obvious issues like hay fever, there could be an increase in cataracts, skin cancer and even tropical diseases such as Dengue fever and West Nile virus. Even now, mosquitoes carrying such diseases are invading the US because of rising temperatures. Overall, it's clear that the cost to society, the environment, our health and the economy is going to far outweigh any perceived benefits of a warmer UK. But luckily, there's something we can all do about it.

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