Conference looks at the effects climate change will have on biodiversity, including changes in habitat and threats of extinction, writes Harry McGee
AN OUTBREAK of the bluetongue virus which affects cattle and sheep would likely occur in Ireland if temperatures continue to rise, according to a leading climatologist.
Ray McGrath, head of research at Met Éireann, said the virus transmitted by culicoides (midges) is associated with the Mediterranean region but has been moving northwards in recent years. There was an outbreak in 2006 in the Netherlands and Germany and a further outbreak in Britain in 2007.
The latter outbreak likely came about by midges blown across the channel from mainland Europe.
"There is a strong suspicion that the [move of bluetongue northwards] is connected to the changing climate," said Mr McGrath.
"In a warming climate, it seems that it will come to Ireland at some stage." He said that in those circumstances more midges are likely to survive the winter due to higher soil temperatures and higher rainfall.
Mr McGrath was speaking at the three-day Climate Change and Systematics conference at Trinity College Dublin, which is looking at the effects that climate change will have on biodiversity, including changes in habitat and threats of extinction.
Mr McGrath said that the particularly bad summer we have had is not redolent of any trend associated with climate change, though he said that the data suggest Ireland is experiencing warmer conditions.
He cited data collected in Birr, Co Offaly which shows that the number of frost days each year has fallen from an average of circa 50 per annum in the early 1960s to below 40 per annum in recent years.
He said that with temperature increases, autumns and winters could experience increases of between 15-25 per cent in rainfall by the end of the century. Conversely, summers could be up to 18 per cent drier.
Sea temperatures are also rising since the 1980s by between 0.3 to 0.4 degrees per decade, particularly in the Irish sea.
"The trend will continue and possibly accelerate which will have impacts on marine ecology. Inland river temperatures are also rising which will have impacts on cold water fish," he said.
There will also be an increase in the frequency of very intense cyclones affecting Ireland, with an increase in sea surges during storms.
"Sea levels are expected to rise by 23-47cm by the end of the century but those estimates are probably conservative. Some of the shorelines around Ireland are very exposed. The southeast coast with its very soft margins will be particularly vulnerable," he said.
Mr McGrath emphasises that climate change models, though becoming increasingly sophisticated, are not perfect, nor do they provide a perfect simulation of reality.
The conference was officially opened yesterday by the junior environment minister Micheal Kitt.
The Sixth Scientific Statement of the Royal Irish Academy and Irish Committee on Climate Change was also launched. This examines the impacts of climate change on biodiversity.
One finding of the RIA paper was the significant increase in the number of birds breeding in Ireland for the first time. They include the little egret, the reed warbler and the Mediterranean gull.
"This is at least in part due to recent increases in spring temperature, says the RIA statement.
The statement continued: "In a recent survey of 850 native Irish plant species carried out by Dr Peter Wyse-Jackson at the National Botanic Gardens at Glasnevin, 171 (20 per cent) appear to be particularly vulnerable to climate change up to 2050 and 52 per cent of already threatened species are increasingly threatened by climate change."
Rory Hodd and Micheline Sheehy Skeffington of NUI Galway looked at the potential impact of climate change on rare montane plant communities, found on the oceanic mountains of Donegal, Mayo and Kerry.
The botanists found that the main threat posed to these rare species are over-grazing by sheep, especially in Connemara, where rare bryophytes have been grazed to extinction.
They also indicated that rising temperatures and drier summers would have implications for some species which require cooler temperatures, higher altitudes and at least 220 days of rain each year, conditions which currently pertain in the mountainous regions of the west.