"It is the first opportunity for the new Government of Jacinda Ardern and us to stand up on the world stage and to say, 'there is a significant change in New Zealand's policy and we aim to lift our ambition massively and go from being something of a follower to one of the world's leading countries in the fight against climate change'.
"We aim to be a carbon neutral economy by 2050 - that would put us in the leading pack of the top 10 countries."
He said New Zealand has copped fair criticism in the past for "not really doing anything to reduce our domestic emissions, and in particular using international carbon credits to pay other people to reduce their emissions so we don't have to. I think that criticism was valid."
The conference aims to develop rules to implement the Paris Agreement, which aims to keep global temperatures from rising 2C above pre-industrial levels, and limit the rise to 1.5C.
Shaw said the visit to the Pope was also significant.
"He's hosting a meeting of Pacific Island leaders on their way to Bonn to lift the profile of the immediacy and the urgency of the challenges that the Pacific Island states face."
Meanwhile, Shaw said discussions had begun to allow Pacific peoples fleeing climate change to migrate to New Zealand. He was not sure yet if they would count towards New Zealand's annual refugee intake as "they're not covered by the UN convention".
"Well before you get into the technical conversations, or even whether it's a specific visa category, the first principle is that people who are displaced by rising seas are going to need some way of migrating with dignity.
"It's not urgent because the number of people displaced internationally from rising seas is low, but we know we've got to get ahead of the problem."
He hoped global action on climate change would minimise the number of those displaced by climate change.
"They don't want to lose their country, and we don't want them to lose their country either. [But] we know that there is internal displacement. And that is going to lead in the not-too-distant future to external displacement. We do want to get ahead of it."
He hoped to make significant progress this parliamentary term.