Published in Science, the 2017 report notes the effects of climate change on diverse populations from reindeer farmers in the Arctic to tourism operators and fishers in the Mediterranean, whose businesses have floundered as invasive jellyfish take over the lagoons.
“Effects like these have already happened, are continuing to happen, and they are accelerating,” Stephen says.
As tropical climates spread towards the poles, we’re seeing the range of disease-bearing Anopheles mosquitoes rapidly increase. Diseases like dengue, Ross River fever, and malaria are now spreading into areas that they’ve never accessed before.
“For example, Brisbane will become more and more suitable for the Anopheles mosquito, putting the whole population of Brisbane at risk,” Stephen says. “This happened in Mexico City – all of a sudden, you have a population of 20 million people exposed to malaria. Tropical diseases pose a real threat to some Australian cities, such as Brisbane and Sydney, over coming decades.”
Increased water shortages are also a real possibility as the climate changes over the next 30 years – and not just because of shifts in rainfall.
“Most of our water in north-eastern Queensland comes off the mountains,” Stephen says. “With climate change, the cloud base gets higher, so clouds don’t hit the top of the mountains like they used to.”
When clouds hit the top of a mountain, water is transferred from air to ground as droplets condense on leaves and trunks. “So, regardless of whether rainfall changes, with that slightly higher cloud, one-third to a half of all the water going into the streams is lost,” Stephen says.
“In 10 years’ time, a city like Cairns could have a growing population and a shrinking water supply.”
“It’s not all doom and gloom. It’s possible to stop the worst of this, but only if everyone got together and worked on it now.”
Adjunct Professor Stephen Williams; TESS, JCU
The future of food
Agriculture could change rapidly over the next 50 years or so, as rainfall and temperature patterns shift. This will lead to major population movement, and changes in the careers, livelihoods, and economic conditions of entire communities.
“There will be winners and losers in agriculture,” Stephen says.
“Any crop that depends on natural rainfall and natural sunshine will shift, meaning places that are not suitable might become suitable – for example, Sydney and southern Australia could grow tropical fruits.”
Of course, the opposite scenario will also play out – farming regions in places that already have high temperatures, such as in Africa and central and northern Australia, could become much drier and experience more severe droughts, preventing them from sustaining crops as they have been for centuries.
A rise in pests will also have a major impact on agricultural commodities around the world, due to both shifts in climate and a decline in pest-eating species. “Pest species by their very nature are able to take advantage of changing situations,” Stephen says. “They usually tolerate a much wider variety of environments, and they’re able to breed fast.”
Sea level rises are often the focus of fears regarding the impact of climate change on humans, and although such rises have so far been minimal, the effects are substantial. In January 2018, a new $24.5 million seawall on Saibai Island in the Torres Strait failed to prevent serious flooding during a king tide, and the tiny Pacific nation of Kiribati is planning to physically raise up its islands to escape the encroaching seas.
And that’s not even the half of it.
“There’s a real chance of a catastrophic event in the next 50 years. In Antarctica and Greenland there are huge ice sheets, and there’s a chance that, with warming, these ice sheets will slip off into the ocean,” Stephen says.
“If that sort of thing happened, you don’t get a slight rise in sea level – you can get a catastrophic rise in sea level over a very short period of time. Roughly 90 per cent of the world’s population lives within 10 metres of sea level, so we’re talking about a complete global meltdown.
“No one really knows how likely that is to happen, but it’s a total game-changer.”
The human effect
While there’s no easy fix for these problems, life on Earth has proved time and again that it’s able to adapt to some pretty extreme shifts in circumstances.
But if we humans want to continue living comfortably on the only viable planet in the known universe, we can’t just sit back and watch global temperatures rise – we actually have to commit to taking action.
Every few years, the Intergovernmental Panel on Climate Change (IPCC) publishes a set of scenarios based on research from thousands of scientists around the world, to predict what the planet will look like depending on the level of action the global community takes to mitigate the effects of climate change.
At one end of the scale, we see what the world would look like if we did everything humanly possible to address climate change. At the other end, we see what would happen if we continue ‘business as usual’ – that is, not taking climate change seriously enough do much about it.
The two scenarios in the middle predict what would happen if we stepped up and did more than we’re currently doing to combat the effects of climate change.
“If things continue as they are, it will indeed be bad. But it’s completely feasible – technically and economically – for the world to follow one of the medium scenarios,” Stephen says.
“It’s actually possible that, without sending the world into depression, we can follow a reasonable middle ground that will still have adaptation benefits. It’s not all doom and gloom, it’s possible to stop the worst of this, but only if everyone got together and worked on it now. It requires the willpower of politicians and the public to do it.”
As the former director of the Natural Ecosystems Network within the National Climate Change Adaptation Research Facility (NCCARF) in Queensland, Stephen has spent decades working on solutions to the problems created by climate change. And according to a recent report by the organisation, the biggest hurdle to overcome isn’t a lack of innovative solutions that will make a serious impact. The biggest challenge is us.
“The biggest barriers to getting things done were the social barriers,” Stephen says. “It’s obviously very complex – there are economic considerations, and human psychology is incredibly complicated.”
“For example, there have been lots of studies looking at why certain people can adapt their businesses and lives to climate change quite well, while others find it incredibly challenging, and it comes down to factors such as their social networks, their age, and their psychology.”
On top of wrestling with our own preconceptions when it comes to adaptive measures, Stephen says the other big change in mindset that needs to happen relates to how we protect our most precious, unique, and threatened wildlife.
For decades, designated national parks have served as a good protective measure, but they can’t address the major challenges of a warming planet, Stephen says.
That’s why he’s spearheading research into more flexible national parks of the future, which can shift in response to a changing climate.
“We need to take a more dynamic, proactive approach. We should be looking forward to where we can protect species in the future and establish corridors for them to travel to more suitable habitats elsewhere as the climate warms,” he says.
“It’s one of the biggest paradigm shifts that we need to get our heads around, because it changes almost everything, especially in how we design policy and management actions around climate change.”