The Opposition parties are calling on the Minister for the Environment, Mr Dempsey, to act quickly in relation to global warming in the light of the current bad weather and flooding.
The Labour Party environment spokesman, Mr Eamon Gilmore, said the Minister should draw up a national strategy to cope with the threat of climate change.
"It is clear now that the process of climate change is having a real effect on our weather. The severe storms which have hit both Britain and Ireland over the past week will, in all likelihood, be a regular feature of our weather over the coming years. It is time that we established a co-ordinated national plan to deal with this reality," said Mr Gilmore.
The Green Party called on Mr Dempsey to make an official statement acknowledging that the extreme weather conditions were a direct result of global warming, and outlining the plans he would put in place for flood protection.
"The UK Environment Minister, Mr Michael Meacher, made a statement last weekend stating that the storms in Britain were a direct consequence of global warming," said the Green deputy, Mr John Gormley. "Noel Dempsey must alert the public now to the seriousness of climate change and outline his plans for flood protection now."
He said the Minister was neglecting his responsibilities by failing to alert the public on these issues. There should be a public information campaign, he said.
The Fine Gael environment spokesman, Mr Ivan Yates, called for an immediate assessment to be carried out in the areas worst affected by floods.
"The enormity of the damage and suffering inflicted by these floods is unprecedented in living memory in some specific areas.
"A multimillion-pound package should be made available from this week's Cabinet meeting to ensure that the real suffering of many in the worst affected areas is kept to an absolute minimum," he said.
The Labour party deputy, Mr Sean Ryan said the Minister for Defence, Mr Smith, should sanction the deployment of the Army and the FCA.
A spokesman for Mr Dempsey said the Minister was in Brussels for a meeting of EU ministers on climate change.