Zoe Leviston, a social psychologist at CSIRO and lead author of the survey, said the ranking was "surprisingly low", not least because more than 70 per cent of respondents also judged climate change to be either somewhat, very or extremely important. Dr Leviston said the low ranking may reflect people turning off the issue because it had become so politicised, artificially pulling the ranking down. The survey, which polled 5219 people, found 81 per cent of respondents agreed that climate change was happening. A question asking respondents to estimate the contribution humans were making produced a score of 61.7 on a scale of 0-100 per cent confidence. Some 56.5 per cent of those surveyed thought temperatures had increased since 1990, with more than 60 per cent saying they expected temperatures to rise over the coming 20 years. About a quarter thought temperatures had been stable and would remain so, the survey found.

The World Meteorological Organisation declared on Tuesday that 2013 was the world's sixth-warmest on record. Last year was also Australia's warmest in a century of records, the Bureau of Meteorology said last month. Thirteen of the 14 warmest years since instrumental records began in 1850 have occurred this century, with 2005 and 2010 the equal warmest, and 1998, a strong El Nino year, was the third warmest, the WMO said. Another finding from the CSIRO survey is that people tended to underestimate how widely accepted climate change is in the community. "Climate change denial, or contrarism, or whatever you want to call it, is overrated," Dr Leviston said. On the other hand, people tended to assume they were doing more to improve the environment than others - a so-called "self-enhancement bias" - even when they were not. "We do find this tendency to inflate how good we are," she said.

The survey, carried out each year in July and August for the past four years, has shown the importance placed on climate change to be relatively stable. Among sources of information, trust has trended higher for most groups, with university scientists the most trusted. Loading Trust in governments, car companies and oil companies were the lowest among 13 groups tracked, but these too had risen over the surveys. (See earlier surveys here.) Follow us on Twitter