Climate Change Lecture

Professor Janette Lindesay will answer this question, and related ones, in a free public lecture at Questacon on Tuesday 19 March at 1pm. The lecture is suitable for ages from 12 to adult. Aspects of climate change that Professor Lindesay will cover include; evidence of climate change, mechanisms of climate change, effects of climate change and the challenge of building a better future.Professor Lindesay will focus on global warming, and will present the evidence for it. She believes it is important to show people evidence based on careful and exact measurements, unrelated to theories or models.Professor Lindesay has worked in the areas of climate variability and climate change since the early 1980s and has a wealth of knowledge to share. She is a prominent Canberra scientist, based at the ANU. She will have a prepared handout available at the lecture which will list resources the audience can use to verify and investigate evidence for themselves.

Evidence for climate change

One of the pieces of evidence she spoke to me about is a graph which plots the distribution of temperature for each decade from the 1950s to the 2010s. What is interesting about the data she showed me is that average temperature is increasing each decade, but the data is also less clustered about the mean, meaning there are more temperatures further from the mean than in the past.

Another piece of evidence Professor Lindesay referred to relates to human activity and increasing carbon-dioxide levels in our air. While she acknowledges non-human and cyclical sources of warming exist, she points out that evidence shows that as we have used fossil fuels and changed the nature of our land coverage, not only have carbon dioxide levels gone up, but oxygen levels have gone down. She explains this is evidence that extra carbon is being created which is bonding with the oxygen. And the Professor says that while human beings are not the only factor in increasing carbon, “we are the thing that we can control.”

People who do not accept that humans have had a large impact on global warming often speak about the effects of natural climate variability, solar events, changes in earth’s orbit, and volcanic eruptions. Professor Lindesay will discuss climate change in context of climate history and consider the contributions of these other sources of warming.

If she has time, Professor Lindesay will also talk about extreme climate events- a consequence of global warming which is already starting to happen – more extremely hot days, more heat waves, more intense

storms, and the consequences of these.

Towards the future

Professor Lindesay will also talk about possible futures and courses of action we can take to improve things. She referred me to an interesting chart which shows predicted effects of temperature change on various aspects of our life. It refers to possible outcomes in 2025 and also possible outcomes towards the end of the century.
She is very concerned that both actions we take and claims made by climate scientists should be based on accurate and carefully interpreted data, gathered and analysed in the best scientific tradition.