The best questions from Stuff's climate change Q&A with Niwa scientist

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The best questions from Stuff's climate change Q&A with Niwa scientist

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A Niwa climate change expert joined Stuff for a live chat to answer questions from readers on Tuesday. The Q&A came after a report from Intergovernmental Panel on Climate Change was released. Niwa principal scientist of atmosphere and climate Dr Olaf Morgenstern said the report was a call to action, and efforts to cut out greenhouse gas emissions needed to be increased in order to keep global warming at 1.5 degrees. Here are some of best questions from Tuesdays Q&A. READ MORE: * IPCC report: It is time to respond and urgently adapt to the new climate realities * Looking ahead to Glasgow, let's not curb our enthusiasm * What the big climate report said about New Zealand * Climate Explained: Why is the Arctic warming faster than other parts of the world? Is it likely we'll see more flooding events, like Cyclone Gabrielle, or droughts, in the future? Yes, that is absolutely likely to happen. The report makes the point that for every additional warming there is an associated increase in extreme events such as flooding. I've noticed an increase in humidity this summer. What is the likely ongoing impact of the rise in humidity levels? Humidity in the air is a function of temperature. It increases by about 7% per degree of warming. The consequence is that pretty much all rain events are correspondingly more intense accordingly. This summer we are having a La Nina event in the tropical Pacific which means warm sea-surface temperatures in the Coral Sea region where the cyclones that affect us originate. Also, it's warmer than the "norm" to the north of here, causing the severe precipitation this summer. This is all natural variability on top of the general climate trend. What is the biggest misinformation around climate science that you regularly come across or are asked about? There is a lot of misinformation around. One standard line is that climate has always been variable and now is no different. The rate of change we are experiencing is, however, very fast even compared to transitions out of ice ages, for example. IPCC is regarded as being generally conservative due to policymakers influence toning down the risk statements. Do you regard the AR6 reporting as "under-baking" the true predicament? Indeed, IPCC is rightly conservative and strictly representing the scientific understanding. Given the general unemotional tone in the document however, I think its language is very straightforward. It basically says that unless action is taken to reign in global warming, we will be inhabiting a much less hospitable planet with many consequences of that. The report says that "deep, fast, and sustained reductions" are needed to keep 1.5 degrees within reach. I don't think this can be called "under-baking". Does planting pine trees help or hinder our response to the climate emergency? (There was some research in New Zealand that suggested Terpenes from pines make the climate emergency worse.) In the long term afforestation always makes sense provided the carbon remains bound in the tree or is harvested and used as construction material or other durable uses. The terpene emissions would increase ozone a bit, but this is a short-term problem. The issue with carbon is that its lifetime in the climate system is essentially infinite, whereas other climate forcers like terpene are there only for hours. So I don't think that argument holds any water. Are we doing enough climate science in Antarctica? I know there's quite a lot there, but does it hold the secret to how to deal with the problem? I can't comment on whether we are doing enough research in Antarctica. Antarctica is clearly a very interesting continent to study. For example, how much sea level rise we will experience depends on glaciers in Antarctica that we don't well understand. Also ice cores record several 100,000 years of climate history there. In this time however, there isn't a direct analogue to what we are going to experience in this century. I live in a town by the ocean. How worried should I be about the future with climate change? Not all towns are created equal. It depends on how high up you are. Sea level rise is highly uncertain in the long multi-centennial timescale, but in the short term we are dealing with millimetres per year of sea level rise. If you live very close to sea level, there may be reason to worry about storm tides in the near term. Some questions and answers have been edited slightly for clarity.