A FORMER Grafton High School student has learned a thing or two about the effects of climate change and he will take to the water in his canoe "Old Yella" to spread the word.
He expects to arrive in Yamba at about 5pm on Monday after setting out from Ballina on New Years Day on the last leg of his Connecting Climate Chaos journey that has taken him around the world.
He expects to collect another 100,000 signatures for his Climate Emergency Declaration petition, which he aims to deliver to Canberra politicians at the end of his journey.
On his final leg he will paddle 1200km to Moruya, before dragging "Old Yella" up the mountains to the Nation's capital.
There are around a dozen events organised at cities and towns on the way, including Coffs Harbour, Port Macquarie, Newcastle, Sydney, then Canberra.
The petition Mr Posselt will deliver asks Parliament to declare a climate emergency and mobilise resources to restore a safe climate.
It can be signed at http://climateemergencydeclaration.org/sign.
Mr Posselt said the science of climate change is alarming, but he can reduce it to relateable figures.
"When I became aware of climate change I had to accept some unpalatable truths," he said.
"What the science is telling us is if we follow all the promises they made at Paris, my grand children will have a 67% chance of living a full life expectancy.
"That is they have a one in three chance of having an earlier than expected death because of the effects of climate change."
Mr Posselt said that as an engineer he learned to accept science and risk
"One in three is a pretty high chance," he said. "When there was a one in 1000 chance of the Wivenhoe Dam over topping they spent millions to fix it. But we're willing to gamble the future of the whole of humanity on the toss of a coin."
Mr Posselt graduated from Grafton High in 1970s and went on to a successful career in engineering before coming to grips with climate change about 2005.