SUPERANNUATION funds and other long-term investors are handling their climate-change risks with ''reckless mismanagement'', according to the compilers of an international climate investment index.

A survey of the world's 300 largest retirement funds, insurance companies and other big investors found ''many didn't even have a climate policy and many that did hadn't changed investment decisions as a result'', said John Hewson, former Liberal leader and chairman of the Asset Owners Disclosure Project.

The findings painted ''a disturbing overall picture of greenwash and reckless mismanagement'', he said.

The AODP claims its climate index is the first of its kind to rate funds according to key measures, including transparency, risk management and low-carbon investment. Only two funds were deemed to warrant a AAA rating, one of which was Australia's Local Government Super.

The AODP contrasted the involvement in the survey of Local Government Super - with $6.5 billion funds under management - with the $80 billion Future Fund, which it said didn't participate because of ''inadequate resources''. But Future Fund spokesman Will Hetherton rejected the claim, saying the government fund took environmental, social and governance issues, including climate change, ''very seriously''.

''We get a lot of requests and we have to be selective, and we took the view that participating in this particular survey wasn't going to be valuable,'' he said.