Ireland could face "droughts in summers and excessive winter storminess and rainfall" as a result of climate change, the Minister for the Environment has warned.
Speaking as he attended a conference on the issue in Marrakesh, Morocco, Mr Dempsey said climate change would "affect us all".
The Conference is the latest round of international negotiations involving Parties to the UN Framework Convention of Climate Change.
Mr Dempsey said it was expected to be the culmination of four years of negotiations aimed at achieving compliance with the reductions and limitations agreed at Kyoto.
"Following a successful conclusion of these negotiations Ireland will prepare to ratify the Kyoto Protocol along with other EU member states, to help ensure its entry into force during 2002," said Mr Dempsey.
He said this was a "key objective of the EU" as it prepared for the World Summit on Sustainable Development to be held in Johannesburg. South Africa in September next year.
Before he left for Morocco, Mr Dempsey urged people to attend an exhibition underlining the global nature of the issue of climate change, at the ENFO centre in Dublin.
Images Beyond the Naked Eye, which runs until December, is built around a series of photographs taken by international photographers, conveying the implications of climate change.
"Anyone can see from the images at this exhibition that climate change has the capacity to cause serious damage in many parts of the world," the Minister said.
"We must recognise that the harmful effects will be magnified many times where people are least able to cope," he added.