The Taoiseach said he hoped the president of the United States would take a different view on pollution. Mr Ahern was speaking in the Dáil before the outcome of the presidential election was known.
He was replying to the Green Party leader, Mr Trevor Sargent, who described President Bush as "a man who lives in continual denial of the need to address climate change".
The Taoiseach said that he hoped "whoever is in the White House will now take a more enlightened position than four years ago when the Kyoto Protocol was rejected and the US refused to work with other states".
He added that the outgoing US administration began to examine Kyoto in the last year and that the issue was discussed at the G8 summit. "Whether it is President Bush or Mr Kerry, I hope the incumbent will take a more enlightened position. There is considerable pressure on the US to do so."
Mr Ahern said that in the Republic, investment had been made in drainage, sewerage and other schemes to ensure that the flood issue could be dealt with in a more efficient way.
He added that while he was not a planner, the State's "system of planning is more regulatory, bureaucratic and less efficient than anywhere else".
Mr Sargent said that the US president, whoever it might be, would find it "a bit rich for the Taoiseach, representing the most power-dependent country in the world per capita, to be telling him to get his act together about climate change".
He added that the Taoiseach had stood over the demise of any prospect of a carbon tax.
"He now claims everything will be fine and our Kyoto commitments will be met.
"He knows that this is not true and we will have to buy our way out, costing taxpayers money," said Mr Sargent.
Mr Ahern said that, four years ago, he was one of the first, on behalf of the EU, to raise with President Bush Ireland's opposition to what he had stated about the Kyoto Protocol.
"I accept the deputy has a problem with the additional 450,000 houses, but he failed in his reply to say where we should have put those people."
Mr Sargent replied: "A flood plain was not the place for them."