We were privileged to enjoy a very comprehensive, balanced and clear address from Dr. Geoff Duffy of the University of Auckland on the complex misunderstood subject of Climate Change.
Geoff took us on a measured and well marked trail, starting from the difference between weather and climate, past the make up of the atmosphere, skirting the relative importance of the various so called Green House Gasses (GHG) right to the door of the overwhelming influence of water vapour on climate.
His logical analysis outlined and supported his very clear hypothesis that, because water vapour, not carbon dioxide, is (by a country mile) the most significant and influential GHG, the emphasis placed by the popular media and IPCC is mistaken and misrepresents what is essentially a result of 4.5 billion years of naturally changing climate on earth.
He underlined how climate not only reacts to the changing composition of the atmosphere, but also a myriad of other factors. These include the strength of the sun which varies over time, volcanic activity, the elliptical nature of the earths orbit and the natural mitigation of these forces by the compensation of clouds, and yes water vapour!
Given the importance to the NZ economy of the Dairy Industry Geoff made special mention of the negligible effect of Methane on climate, another serious misrepresentation. 
Geoff's talk was enormously well received, he has kindly offered to accept questions and discussions and can be found at geoffduffy@lycos.com and 09 479 9383, and his talk can be viewed here.