Hard copies are available free of charge while stocks last by contacting gsisales@gsi.ie or the GSI Customer Centre (phone 01-678 2868). 
Download Map (6 Mb).
Further Information on the project is available from Brian McConnell at 01 678 2850 or by e-mail.

New Climate Change Map – March 2009
Climate change is nothing new

Earth’s climate has changed throughout the billions of years of our planet’s geological history. Evidence for past climates - including the extreme conditions linked to mass extinctions - can be found in the rocks around us. 'The present is the key to the past' is a vital principle of geology. As our geological understanding improves, so we are better able to forecast the impact future change may have on us — the past is the key to the future, too.

Many rock-forming environments are directly influenced by climate. This is the rationale for a new poster map of Britain and Ireland, jointly produced by the Geological Survey of Ireland, the British Geological Survey and the Geological Survey of Northern Ireland. The map, at a scale of 1:1.5 million, shows the rocks classified in a new way — according to the environment in which they formed.

Were your local rocks formed in a desert, or a tropical swamp, or a cold seabed? And what is the evidence that geologists use to tell this? The poster includes photographs of distinctive rocks showing the evidence that ties them to modern environments around the globe. A geological timeline displays how global temperatures and sea levels changed through time, the positions of Britain and Ireland as they drifted northwards across the Earth, and typical plants and animals from the fossil record for each geological period.

The poster was launched at the end of March and it is free. Print copies are being distributed widely by each geological survey, and the poster will also be available to download from the surveys’ websites. It has been endorsed by a range of teaching organisations in Britain, Northern Ireland and Ireland, and classroom exercises will also be available to download.

We hope that the poster will foster an understanding of the Earth’s climate and geology as a dynamic system – a system which has changed in response to extreme events in the past, and which will continue to respond to future changes.

Ireland’s Changing Climate

People are fairly aware of the Ice Age that gripped our part of the globe between 2.6 million and 12,000 years ago, carving our mountains and shaping the lowlands with mounds of drumlin and esker. But there have been several ice ages in Earth’s history. One of these was in full swing about 300 million years ago (during the Carboniferous Period), but the ice age didn’t affect Ireland which then lay in equatorial latitudes, on its journey from the southern to northern hemisphere. Rising sea level spread a warm, shallow sea over Ireland, in which coral reefs formed, like in today’s Bahamas or Great Barrier Reef. The limestone deposited in those warm seas, rich in fossil remains, are widespread across the Irish midlands.

Then, as sea level receded, tropical swamps accumulated layers rich in plant remains, forming coal that locked-up atmospheric carbon dioxide. This greenhouse gas is now being released back into the atmosphere as we burn the coal and the other fossil fuels, creating new and potentially rapid changes to climates around the Earth. By studying the record of past climate change, we gain insights into the scale and effects of potential change, including, in the extreme, desertification and mass extinctions.

Deserts have spread over Ireland during two past geological periods. Both resulted from a combination of high global temperatures and Ireland having a tropical position. Fossil sand dunes are preserved in the red sandstones of Cork and Kerry from the Devonian desert of 350 million years ago, when Ireland was in the southern tropics. After crossing the equator into the northern tropics, cycles of sea level rise and baking desert produced the salt and gypsum deposits of Carrickfergus and Kingscourt. During this second desert phase, the largest mass extinction to have affected Earth occurred (at the end of the Permian Period) when over 90% of species became extinct, preparing the way for the evolution of the dinosaurs and the mammals.

View Official Press Release