Is climate change to blame for the Australian bushfire disaster?

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Rain eventually returned to parts of the fire-affected provinces in Australia’s East last week, bringing some much-needed relief to a country shrouded by the persistent threat of a natural force stronger than their ability to fight it. Today heat and wind returned, fuelling blazes that forced a partial evacuation in parts of Australia's capital, Canberra. The damage already caused by bushfires is being widely described as ‘totally unprecedented’ which is a sterile way of saying that, all things considered, these wildfires are the most devastating that humankind has ever witnessed. So why now? What’s created this perfect firestorm? The answer to that question is multifaceted and complicated, but first here’s what you need to know.

For weeks the eastern territories of Australia have been engulfed in a fiery inferno that’s so massive and intense it’s difficult to really wrap your head around it. 24 million acres have been burnt. That’s an area bigger than the entire state of Indiana. That figure represents the combined damage of hundreds of separately burning fires. The largest blaze, called the Gospers Mountain Fire, burnt through an area bigger than the whole of Rhode Island. As the fires rage, they’ve produce enough smoke to blanket the entirety of Russia and a third of Europe: 20 million square kilometres of smoky skies.

Locations of Australian bushfires, as represented by NASA's Fire Information for Resource Management System.

29 people have died, while thousands more have been displaced, their homes and towns burnt to the ground as they look helplessly on, crowded on beaches to await evacuation by the navy. The cost to animal life and Australia’s unique ecosystems has been far higher. More than a billion animals have died according to expert estimates. In this instance, ‘animals’ refers to mammals, birds, reptiles, insects, bats and frogs. But the deaths of just the first three categories are estimated to total more than 800 million. That’s the equivalent of 1522 mammals, birds and reptiles being killed every minute, of every hour, of every day, for a full year. Many of these belong to species that are threatened or endangered, and exist nowhere else on earth. It’s a horrifying amount of loss.

The countrywide average daytime maximum temperature in 2019 was 30.7°C / 87.2°F . The hottest recorded temperature for the year was 49.9°C / 121.8°F

So why has this happened? What is it about this moment in time that sets it apart from the rest of human history? The answer is complicated and different explanations have been widely oversimplified and politicized to fit people’s ideological predispositions. Many are saying, ‘this is the result of climate change, clear and simple’ while others have responded that the fires were intentionally started by arsonists amid an ‘arson emergency’. While both claims hold elements of truth (one less than the other) neither gives a thorough or clear explanation of what has caused this disaster.

Let’s start with the latter explanation: the arsonists. 

Claims have circulated online that hundreds of people have been arrested for arson since the fires started. This is simply untrue. It is true that a handful of people have been arrested for intentionally starting bushfires, but the figures being thrown around the twitterverse were greatly inflated by irresponsible reporting and what one study has described as a deliberate misinformation campaign. While arsonists may have started a number of fires, their actions can’t explain what has led to these being the most devastating wildfires in human history.

So here we are at last: is climate change to blame?

2019 was both the hottest and driest year in Australia since people started recording measures of things like rainfall and temperature, way back in 1900. The countrywide average daytime maximum temperature in 2019 was 30.7°C / 87.2°F. The hottest recorded temperature for the year was 49.9°C / 121.8°F with January 16 reaching an incredible continent-wide average temperature of 40.9°C / 105.6°F. Australia is also in the grips of a three year drought, with large areas experiencing the lowest-ever recorded rainfall over the last three years. You don’t have to be a campfire aficionado to know that hot and dry burns faster than cool and wet. As temperatures continue to rise with a warming climate, fire seasons around the world have increased by roughly 20% in duration. It makes sense that unprecedented heat and dryness would lead to unprecedented fires. But to truly accurately describe the situation in Australia you have to take consideration of specific weather patterns as well as the general trend of a steadily warming climate. Two weather patterns are particularly relevant: the Indian Ocean Dipole and the Southern Annular Mode.

The heat across the continent on the day Australia's average temperature was almost 41°C, as shown by the Australian Bureau of Meteorology.

 The Indian Ocean Dipole refers to cycles of water temperatures in the Indian Ocean which resulted in more cold water closer to Australia in 2019, meaning less evaporation and therefore less rain. The Southern Annular Mode refers to wind patterns around Antarctica which also resulted in a drying effect over Australia in 2019. These two phenomena had a direct impact on the Australian weather that created the conditions for the wildfires to erupt on such a massive scale. They’re also phenomena that exist independently of human-caused climate change. Whether the earth was warming or not, there would still be cycles of changing ocean temperatures and wind patterns around Antarctica. 

To say that climate change alone was the cause of the disaster wouldn’t be a scientifically thorough way to describe the situation. The combination of weather phenomena taking place within the context of a steadily warming climate is a better way to describe it. No matter how we describe it though, one thing remains scientifically established and certain: the more the global climate warms, the more damage and destruction we are going to see from wildfires. The scary thought is that these ‘unprecedented’ fires will, in time, be remembered as just the first of their kind.