WELLINGTON, Jan. 18 (Xinhua) -- Almost half of New Zealanders are not convinced global warming is real, a survey published on Monday suggests.

    A New Zealand Herald survey has found that although United Nations experts have grown steadily more certain about climate change, the public is not so sure.

    Almost one in five of 2296 respondents said the concept was a giant con, and a further 28 percent said global warming had not been conclusively proved.

    New Zealand Prime Minister's science adviser, Sir Peter Gluckman, said the 28 percent figure was not surprising as scientists were not claiming conclusive proof.

    But he said there was a problem communicating climate science to the public - and scientists and the media were equally to blame.

    An online survey was conducted by the Nielsen Company on December 10-17, 2009, during the UN climate change conference in Copenhagen.

    Thirty-eight percent of respondents said global warming was a serious problem that needed action now, 13 percent said it was the world's biggest challenge, and 2 percent did not know.

    Nineteen percent - including almost 30 percent of men aged 45 or older - thought it was a giant con and a waste of money.