But a sceptical view of the science can be expected from Dr Chris de Freitas, of Auckland University.
Economic opinion is also divided. Vivek Tulpule, research director of the Australian Bureau of Agricultural and Resource Economics, and Alex Sundakov, director of the Institute of Economic Research, will give contrasting results of their modelling of the economic effects of New Zealand ratifying the pact.
As well as business groups that have misgivings about ratification, such as Business New Zealand, Federated Farmers and the Forest Industries Council, there will be speakers from the Business Council for Sustainable Development, which emphasises the business opportunities in a carbon constrained world, and the Federation of Maori Authorities.
Pete Hodgson, the minister responsible for climate change, and Brian Roche, who will negotiate greenhouse gas agreements between the Government and big industrial emitters, are also speakers.
Mr Thompson said that the Government was determined New Zealand should be among the first countries to ratify the protocol this year.
"Before business can agree to this, we need to know far more about the ramifications.
"We need to know what opportunities may exist to compensate for the extra costs the protocol will impose, and what commitments our trading partners have to give if New Zealand is not to be penalised financially for living out our environmental ideals."
nzherald.co.nz/climate
Intergovernmental Panel on Climate Change (IPCC)
United Nations Environment Program
World Meteorological Organisation
Framework Convention on Climate Change
Executive summary: Climate change impacts on NZ
IPCC Summary: Climate Change 2001