Awareness of climate change is high in many countries, especially the tropics, but in Britain, Japan and the United States many are doubtful about the cause, a poll published on Thursday said.

A survey of 13,492 adults in 13 countries who were questioned by Internet found that 88 percent believed the climate had changed over the past 20 years.

The figures ranged from 98 percent in Mexico and Hong Kong and 97 percent in Indonesia to 80 percent in Belgium and 72 percent in the United States.

Rising average temperatures, drought and extreme rainfall were the phenomena that people most cited.

On the question whether climate change had been scientifically proven, agreement was highest in Indonesia, Hong Kong and Turkey (95, 89 and 86 percent respectively).

It was lowest in Japan (58 percent), preceded by Britain (63 percent) and the United States (65 percent).

Asked whether human activity was mainly responsible for climate change, 94 percent of citizens in Hong Kong agreed, followed by 93 percent in Indonesia, 92 percent in Mexico and 87 percent in Germany.

Dissent was strongest in the United States, where 58 percent agreed with the question, in Britain (65 percent) and Japan (78 percent).

The survey was carried out from July 5 to August 6 by the opinion poll group Ipsos for the insurance firm Axa.

It was conducted in Belgium, Britain, France, Germany, Hong Kong, Indonesia, Italy, Japan, Mexico, Spain, Switzerland, Turkey and the United States.