By Sudeep Chand
Are solar changes or greenhouse emissions driving warming?
The British public has become more sceptical about climate change over the last five years, according to a survey.
Twice as many people now agree that "claims that human activities are changing the climate are exaggerated".
Four in 10 believe that many leading experts still question the evidence. One in five are "hard-line sceptics".
The survey, by Cardiff University, shows there is still some way to go before the public's perception matches that of their elected leaders.
The results were announced at the British Science Festival in Guildford by Cardiff's Lorraine Whitmarsh.
A questionnaire survey was filled in by 551 people, from a range of ages and backgrounds, between September and November last year.
Although the findings are similar to those of other UK surveys, this is the first to show that people may be becoming "tired" of claims surrounding climate change.
Dr Whitmarsh told BBC News: "It is difficult for people to perceive what is and isn't climate change.
"But I think what we have to get across is that residual uncertainty in science is normal.
WHO IS THE MOST 'SCEPTICAL'?
Men more than women
Rural more than urban
Conservative voters more than Lib Dem voters; Lib Dem voters more than Labour voters
"Unfortunately, some people latch on to this uncertainty and say 'let's carry on as we are'."
She feels that many people are not "playing their part" in reducing humanity's impact on the environment.
"In general people are showing little willingness to change their lifestyles.
"They will recycle, unplug the TV and change their light bulbs; but they won't change how they travel or how they eat.
"These are the things that are going to make the biggest difference."
Half of the people surveyed believed the media was too alarmist.
And a third said there was too much conflicting evidence to know what is actually happening.
Dr Whitmarsh added: "We need to make it clear to people what is due to climate change and what is not.
"It is time we made it real to people."
Other surveys have shown that people in the UK are more sceptical than those in Europe, but less than those in the US.