Large majorities in many countries now believe human activity is causing global warming, a BBC World Service poll suggests.
Climate change is causing erratic weather around the world
A sizeable majority of people agreed that major steps needed to be taken soon to address global warming.
More than 22,000 people were surveyed in 21 countries and the results show a great deal of agreement on the issue.
The survey is published a day after 150 countries met at the United Nations to discuss climate change.
An average of 79% of respondents to the BBC survey agreed that "human activity, including industry and transportation, is a significant cause of climate change".
Nine out of 10 people said action was necessary, with two-thirds of people going further, saying "it is necessary to take major steps starting very soon".
In none of the countries did a majority say no action was necessary to combat climate change.
The survey was conducted by the polling firm Globescan and the Program on International Policy Attitudes (Pipa) at the University of Maryland in the US.
Globescan President Doug Miller said growing awareness of global warming had awoken people's self-interest.
"The impacts of erratic weather on their property, on their person, on their country is tangible and real to people across the world."
He said "the strength of the findings makes it difficult to imagine a more supportive public opinion environment for national leaders to commit to climate action".
The survey found widespread support (73% of respondents) for an international agreement to limit emissions of greenhouse gases that would include developing countries.
VIEWS ON CLIMATE CHANGE
Major action needed: 65%
Modest action later: 25%
No action needed: 6%
Source: BBC World Service poll
In return, developing countries would get financial and technological assistance from richer nations.
Only in Egypt, Nigeria and Italy did more people take the position that developing countries should not be expected to limit emissions.
A majority in some of the key developing countries favour limiting emissions in less wealthy countries, including China (68%), Brazil (63%) and Indonesia (54%).
On Monday, UN Secretary General Ban Ki-moon told the highest-level UN gathering on climate change that "the time for doubt has passed".
Mr Ban is hoping to inject a sense of urgency to the political negotiations on global warming that are due to be held in Indonesia in December.
"If we do not act now, the impact of climate change will be devastating," he said.
Representatives from about 150 countries, including 80 heads of state or government, were at the meeting, held on the eve of the UN General Assembly.
However, US President George W Bush was not present. Instead, he is hosting a meeting of 16 "major emitter" countries in Washington on Thursday and Friday.
There has been a string of scientific reports in recent months that have pointed to humanity's central role in causing climate change
Just days ago, US scientists confirmed that more Arctic sea ice melted this year than ever before.