Green candidate Keith Taylor blamed global warming for a cliff fall at a Brighton superstore during a pre-election visit to the site.
He said climate change was having a "disastrous effect" on Sussex as he went to the Asda store in Brighton Marina.
He saw where thousands of tons of chalk fell from cliffs during the winter and again this year, closing the store and the Undercliff Walk for several weeks.
As the Green manifesto was launched, Councillor Taylor, who hopes to win the Brighton Pavilion seat, said: "This, and the floods at Patcham and Bevendean, are examples of the effects of global warming.
"Flooding and cliff falls on a scale we've just experienced aren't simply flukes of nature. There's now much scientific agreement that global warming is responsible.
"None of the Westminster parties is tackling the environment seriously and their policies are far too short-term. They are trading in our futures in their sell-offs to big business interests.
"Locally, both Tories and Labour are completely adrift. One denies there's a problem and the other pretends it is doing something about it when just the opposite is true.
"They weren't even prepared to send a protest message to President Bush after his withdrawal from the Kyoto global agreement to reduce climate change gas emissions."
Coun Taylor said Brighton already had the highest Green vote in the country and he was asking even more people to back the party.
He added: "This will highlight the importance of changing towards a way of life which doesn't blight the world and rob resources from future generations."
The store closed in April after rocks and other debris toppled into a yard at the back.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article