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Understanding the science behind our climate crisis

PHOTOGRAPHY @mattabbottphoto.

As the Australia continues to reckon with the devastation of the bushfires, the conversation of the climate emergency we are facing becomes difficult to turn a blind eye to. Our skies transitioned from blue to brown, our cities are experiencing unprecedented temperatures, and our native species, namely the Koala, are facing extinction. In the midst of the horror, loss and pain the bushfires are causing for so many across the country, we are prompted to look at the bigger picture, particularly the facets which have caused such unprecedented, catastrophic burns, and pose the question: is this the new normal? And if not, how can we prevent it from being so?

For those of us who are doing all the things: attending climate rallies (before coronavirus made this impossible), signing petitions, swearing off plastic straws, treating our keep cups as extensions of ourselves, it can still feel as though we aren't living as footprint-free as we would like (particularly when waking up in the morning in January came with the consideration of whether or not you’ll be wearing your smoke mask into the office that day). Here, we asked Professor Nerilie Abram of the ANU Research School of Earth Sciences to help us comprehend what the bushfires really mean for the state of the planet right now, and how we can positively action change to combat the worst of it.

Can you explain to us, for those who aren’t sure, what impacts global warming will have on the earth and why it’s so important the temperature doesn’t rise?
So global warming has a whole range of impact on the climate. The bushfire crisis that we’re seeing at the moment is one of many aspects, and climate change affects these bushfires in a number of different ways. We’ve also got ice being lost form the Antarctic ice sheet and the ice being lost from the Arctic Sea levels rising, and world heritage areas such as the Great Barrier Reef suffering. So, the bushfires are a just one example of what we can expect with climate change, and definitely a wakeup call that says this is something that’s going to get worse unless we take urgent action to reduce future climate warming.

In the wake of the bushfires still  blazing across Australia, the phrase ‘the new normal’ is being thrown around a lot. Can you talk a bit about whether or not this is realistic, and what the ‘new normal’ might actually look like if we continue at the rate we’re going?
I think that it’s a phrase that can be misinterpreted, it conjures this image that we’ve arrived at climate change and then this is what it’s like. When really this is the impact that we can see with global warming of just a bit over one degree, relative to the pre-industrial time, and it’s a worsening trajectory. We’re currently on a trajectory where at the end of this century we can expect warming levels of three degrees or more. So, the type of summer that [we're seeing] in Australia, we can expect these kind of extreme events to worsen in the future. I think that we need to be aware that this isn’t it – this is a glimpse into how things will continue to get worse if we don’t turn around some climate warming.

If the planet does warm by approximately three degrees in the next century, will the planet be uninhabitable for human life?
That’s not something that we can say, it will depend very much on local responses and also on the capability of local communities to be able to respond to the kind of challenges that climate change is going to bring. For example, with the bushfires, one of the things that is being talked about is that we need to improve our ability to fight these fires and improve our resources in order to tackle the worsening conditions. So that’s something we can put resources towards to make the situation more manageable and adapt to these changes. But overall it doesn’t take away the need to mitigate global warming and reduce greenhouse gas emissions so that we can actually start to slow and stop climate warming, then we have the best chance at these adaptations to be able to cope with the kind of challenges we will be facing in the future.

"I think that we need to be aware that this isn’t it – this is a glimpse into how things will continue to get worse if we don’t turn around some climate warming."

"This is something that’s going to get worse unless we take urgent action to reduce future climate warming."

What are some of the biggest contributors to the rising global temperature?
So the scientific assessment is that the warming that we are now seeing is 100 per cent caused by human activity. The biggest factor in those human activities is the greenhouse gasses in the atmosphere through the burning of fossil fuels. What happens when we burn fossil fuels is we take carbon that is stored very safely in the earth in coal, oil and gas, and we burn that and release it into the atmosphere putting carbon dioxide and other greenhouse gases into the atmosphere. Once these greenhouse gasses are in the atmosphere, they prevent heat from escaping the earth, and that’s when we see the warming. Since we started burning fossil fuels in the industrial revolution and since then, we’ve increased carbon dioxide levels in the atmosphere. It used to be 280 particles per million, we’ve now pushed that over 400 parts per million of CO2 in the atmosphere and that’s trapping heat in the climate system.

The one degree of warming we feel in the atmosphere is actually only a fraction of the heat in that’s been trapped in the climate system. New science has actually come out today showing the extra heat that’s being trapped by the ocean. So 90 per cent of the extra heat that we’ve caused to be kept in the earth's system has actually gone into the ocean, so what we feel is only a small part of the actual problem.

Does that heat affect the ecosystems of marine and plant life in our oceans?
It certainly is putting ecosystems under stress. The CO2 that gets absorbed into the ocean is making it more acidic too which affecting the organisms and ecosystems living there, and then another trickle affect that we are starting to see with the heat being trapped in the ocean is that the ocean isn’t able to circulate as well so it’s also losing oxygen. So we have this triple whammy affect of what’s happening in the ocean as well as what’s happening on the land.

What are some tangible things we can be doing to reduce our emissions?
This is a big problem but it’s a problem where the action that we take to reduce greenhouse gas emissions helps to avoid the problem getting worse. We do have climate change ahead of us and we will have these kinds of impacts that we will have to adapt and live with, but we can also avoid some of the worst-case scenarios. There isn’t one single solution and we probably need to pinpoint all of the solutions that we have to hand. We can be looking at our own lives and the things that we do that lead to increases in greenhouse gases in the atmosphere. We can be taking public transport or riding a bike instead of driving the car, looking at ways to reduce your energy use in your own house etc. These are the kinds of things we can do individually, but individually we have a really important role to play in making sure that we hold our leaders accountable and make sure that they know that this is important to the people that vote them into office. So that’s something that I think we’ve seen with the bushfire crisis in Australia, the discussion of climate change in the general public has become more open and more informed and so we can actually play a huge part in driving the momentum to challenge the leadership levels in the country as well.

The bushfires have affected a huge amount of the population. People have lost their homes; people have lost loved ones. People who haven’t been directly affected by the fires are experiencing the hazardous smoke conditions, even people who are just seeing images of places they know and love that have been damaged or destroyed. What we’re seeing is this real crystallisation of what climate change impacts actually mean in a way that is very tangible for people. We can talk about the impacts in the ocean, but these are a lot harder for people to actually see. The bushfires are a way for a lot more people to relate to what this actually means.

Are there any actions we should be taking politically to get our desire for greener policies over the line?
Using your vote. But also remembering that our elected representatives are there to represent us. Write to your local representatives and let them know that this is an important issue to you, so that message becomes very clear that this is a situation you do not want them to ignore and also taking a role in leading the world in where we need to go.