Researchers found that the season's smoke-related health costs totalled almost $2 billion, more than three times the expense of our next-costliest bushfire season.

As I read the news, my mind skipped over the dollar figure and went to a more personal, devastating loss: my mother was likely one of these casualties.

My mum lived in Canberra, which had been shrouded in smoke from the east coast's unprecedented bushfires all summer, and was at one point home to the worst air quality in the world.

A few weeks after the fires began, I was picking up my kids from the final assembly of their school year when my brother called. Mum was in hospital, suffering from breathing difficulties.

I travelled from Melbourne to Canberra to see her. Mum was released from the hospital on Christmas eve. We shared a hasty celebratory lunch before I joined other family in Adelaide.

It never occurred to me that it would be our last Christmas together. A few weeks later, my brother called again - Mum was back in hospital, having a hard time breathing again.

He called again a few hours later, his voice cracking with grief. Mum had suffered a major heart attack. They had revived her, but "it didn't look good".

After an anxious night, I arrived the next morning to see her on life support and to quietly say goodbye. She was surrounded by family and love as she took her last breath.

I had to go home a few days later. My dad was grieving; but to my surprise, as I said goodbye, he quietly said: "I think climate change played a role in her death."

Hospital records would state that my mum died of a heart attack, but they have no way to account for the heat, smoke and anxiety that Mum endured in the lead-up to her death.

In Canberra, temperatures soared above 40 degrees on several days in December and January, and it was 4.3 degrees hotter than average this summer. My parents were already vulnerable due to their age, and Mum had pre-existing heart and respiratory conditions.

Mum and Dad stayed home for most of the summer, trying to escape the hazardous smoke pollution. They turned off the evaporative cooling as experts suggested - this kept out the smoke, but worsened the heat indoors.

The constant oppressive heat, smoke and dark skies were stressful for everyone, but Mum was vulnerable to the mental health impacts of the fires, too.

She grew up during World War II in Germany. She told her friend that the oppressive red sky brought back anxious memories of fire, violence, evacuation and hunger. She talked about the feeling that something would be "hit", but not knowing when, where or whom.

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The compounding mental and physical health impacts of this past summer might not be reflected on my late Mum's hospital records - but we know that extreme heat and air pollution heighten mortality risk.

In the future, should health professionals, as a group of ANU academics recently suggested, add environmental factors to our death certificates and hospitalisation data, to more accurately reflect the deadly nature of the climate crisis?

It is clear that if our society keeps burning fossil fuels like coal, oil, and gas, which worsen climate change, this crisis will take more lives. Everyone is potentially at risk and much of the damage has already been locked in.

But all crises create opportunity. We jumped into dealing with COVID-19 straight after summer, and the reality is that both the fires and pandemic have demonstrated the strong collaborative values of our communities and brought people closer together.

There are diverse voices calling for a recovery that can address both issues simultaneously. Climate solutions have multiple benefits, from clean new jobs to cost savings and better mental health outcomes for people who can deepen connections with their local community.

Australia can reap the many, many rewards of a renewably powered zero-carbon future. One where bushfires, smoke and heat aren't supercharged to unprecedented extremes, and where science, smart economic decision-making and community power have triumphed over the greatest threat to the health and safety of future generations.