Some 40% of adults worldwide have never heard of climate change, a study has found.

Published in Nature Climate Change, the researchers from a string of higher education facilities across the US analysed the awareness and the perceived risk of climate change around the world.

They found slightly more than half of adults on Earth are unaware of climate change, with this figure rising in developing countries.

Co-author Anthony Leiserowitz, director of the Yale Project on Climate Change Communication (YPCCC), said: "Overall, we find that about 40% of adults worldwide have never heard of climate change. This rises to more than 65% in some developing countries, like Egypt, Bangladesh and India. There is still a critical need for basic climate literacy in many countries."

However, in Europe, North America and Japan, more than 90% of adults were aware of the risk of climate change, which led the authors of the report to state that the difference in knowledge between developed and developing countries is "striking".

The researchers garnered the information from representative samples from 119 different countries, collected as part of the Gallup World Poll.

Ezra Markowitz, from the University of Massachusetts Amherst, said: "It was interesting to uncover these differences across countries, but in some ways one of the most insightful outcomes is the reminder that what motivates one person to engage with this issue is not necessarily the same as what motivates the next person.

"Although this is not a revolutionary insight, it is important for communicators and others to keep in mind. Advocates would love a one-size-fits-all approach to climate communication because it would be easier and cheaper, but it is not the most effective strategy; people are too diverse in what connects them to this issue. For communicators this is an important message."