More than 90 people braved the elements last Thursday to hear Professor James Renwick's address on climate change.
His talk was wide-ranging and stimulated numerous questions. from the floor. He discussed all the basic science and past trends and then discussed future scenarios and explained why not exceeding a world average temperature of 2 degrees C since industrialisation about 250 years ago, and ideally 1.5 degrees, is important. CO2 once emitted remains for a very long time.
Countries at the Paris agreement of 2014 put forward their voluntary targets but he said at present the world is tracking at a likely temperature increase much greater than 2 degrees.
He expressed disappointment at N.Z’s uninspiring target of reducing green house gas emissions by 11% by 2030, mostly by buying credits from overseas, which while within the framework of the Paris agreement was not morally defensible. He, and other individuals and groups, had argued for 40% and he explained how this could be achieved fairly readily. The argument that N.Z’s population and impact in world terms is tiny and that we should be followers and not leaders is not the way that we play Rugby.
The difference between observed changes between the northern hemisphere and the southern hemisphere with a smaller land mass and a large circumpolar oceanic current was explained. In summary he said that climate changes will be globally uneven but as warm air holds more moisture, on the whole wet areas will tend to become wetter and dry areas drier. In short, we will experience more extremes and these will have costly impacts. Droughts affect food supply and can cause tensions leading to warfare probably already a contributor to the blood shed in Syria.
The science is now well established, we should be concerned and, need to make our views known at a political level as that is where policy decisions are made..
James Renwick is a professor in the School of Geography, Environment and Earth Sciences, Victoria University of Wellington.