Potato growers may have had their chips in 50 years

The growing of potatoes in the east and south of the country could cease by mid-century because of global warming, a climate expert has warned.

Dr John Sweeney, the head of the Icarus Unit at NUI Maynooth which monitors climate change, said agriculture would change dramatically in Ireland as temperatures increase.

Some of the country's richest pasturelands, including the Golden Vale, will be less productive than now, and farmers may have to bring their cattle indoors during summer droughts to conserve grass.

According to Icarus forecasts, temperatures will rise here by 2 degrees by the end of the century, and summer rainfall levels will be reduced by 40 per cent. Drought conditions are expected to become more common, particularly in the east of Ireland.

At a conference on climate change and agriculture at Maynooth's Kilkenny campus last night, Dr Sweeney said the potato will be the crop that is most dramatically affected by climate change.

Yields will be down all over the country, and it could stop being a viable crop in the east and south without substantial irrigation involving already scarce water resources.

Traditionally, potatoes need a lot of summer rain, especially in August, to thrive.

Dr Sweeney said: "There is no doubt that there is a great cultural attachment in this country to the potato, but we are already seeing in dry summers that farmers are flooding their fields.

"Without irrigation it will be very difficult to grow crops of potatoes in dry areas, but we anticipate that farmers will face competition from cities for that water during the summers."

Other crops, though, will thrive as Ireland becomes hotter and wetter. Barley and wheat will thrive west of the Shannon in the moist conditions. Maize will prosper throughout the country.

Dr Sweeney said agriculture would still thrive in Ireland in the coming decades. " We'll do rather better than many of our neighbouring countries who may suffer a lot more, but it is important to prepare for the changes which will occur."