Fresh calls for action on climate change, with the environment watchdog warning of the serious effects of rising seas around New Zealand.

A climate change report from the Parliamentary Commissioner for the Environment finds that sea levels will rise 30 centimetres by 2050.

A second report, next year, will identify the parts of the country most vulnerable to rising seas but Greens co-leader Russel Norman says we shouldn't wait to act.

"Adaptation can be very expensive, it's why we need to put in the measures now. So we need some leadership from central Government to put in a national policy statement for example on climate change adaptation so councils can prepare."

Dr Norman says the Government needs to heed the findings.

"Climate change is real in spite of what the National Party will say and it's going to have a dramatic impact on New Zealand. We need to start reducing our emissions and we need to be prepared for rising sea levels."