He renewed these comments in front of a packed crowd of about 300 people at the University of Otago's St David Lecture Theatre last night.
He was joined by Dunedin Mayor Dave Cull and Dunedin South MP Clare Curran in a talk considering central and local government's plans and roles in addressing climate change.
Mr Shaw said if the country could create net zero emission agriculture, that would be something the rest of the world would ``want and demand''.
``There is no country in the world that currently has agriculture as part of its emissions trading scheme.
``If we focus on that now that's something we can say to the rest of the world, that's how you do it.''
It was an ``extraordinary opportunity'', as economically that could be intellectual property other nations would want, he said.
Mr Shaw said as well as mitigation of climate change, the Government would seek to deal with the impact it was already having on the country.
``We are experiencing fires in the Port Hills that look more like a Sydney brush fire than anything we've seen in New Zealand before. Or flooding that we're more akin to seeing in the Philippines.''
Mr Cull said there was no more debate necessary regarding whether climate change was happening or caused by humans.
``It's settled; the scientific debate is over.''
