New Zealanders' beliefs in climate change and that humans are behind it are increasing over time, a study has found.
Researchers from Victoria and Auckland universities examined those two beliefs over a six-year period to 2015.
Dr Taciano Milfont, from Victoria's School of Psychology, says they found that the levels of agreement to both beliefs steadily increased and were more pronounced from 2013.
"Overall, belief in the reality of climate change was higher at all times than agreement with the idea that climate change is caused by humans," he said.
"But people who tended to increase their level of agreement in one climate change belief also tended to increase their agreement level in the other belief."
The research, published in the international journal PLOS ONE, used data from the New Zealand Attitudes and Values Study.
Started by Auckland University Professor Chris Sibley in 2009, the NZAVS is a national probability study of social attitudes, personality and health outcomes of 18,000 individuals.
Dr Milfont said it was the first longitudinal study indicating that climate change belief was increasing over time.
Past research had relied on a snapshot of data from one-off public opinion polls.
Dr Milfont said the observed increase could be attributed to a number of factors.
Other studies suggested that beliefs and concerns might change after extreme weather events as well as mainstream media and awareness campaigns.
Dr Milfont said the researchers expected levels of climate change beliefs would fluctuate over time.
With the NZAVS ongoing, it would be possible in future to pinpoint whether particular socio-economic circumstances directly resulted in fluctuations.