Launceston resident Judy Hooley registered the event as part of GetUp's National Day of Climate Action and said there would be a petition circulating to call for stronger action from politicians on climate change.

The event will be staged at the City Park rotunda from 11am and guest speakers will include activist Peter Cundall, Australian Youth Climate Coalition member Katherine Whitmore and Launceston Deputy Mayor Jeremy Ball.

``We want carbon pollution to be reduced by 25 per cent by 2020, a price on carbon and a limit on the amount of emissions put into the atmosphere,'' Mrs Hooley said.

``I'm interested in my grandchildren and great-grandchildren having a clean and sustainable planet to live on.

``We can't trust our politicians to act on this, it's the people that need to speak up - something needs to be done for the future on mankind.''

Alderman Ball said he hoped a dedicated climate action group for Launceston would be formed from the event, while Ms Whitmore said policies needed to be about science not politics.

There are about 190 events scheduled to be held nationwide and those interested in attending are asked to wear red or orange coloured clothes.