The first time Heidi Edmonds felt this type of anxiety creep up, she became teary and had to go into the bathroom for a cry.

"I was looking at my nieces ... and worrying about their future," she says, "not feeling like everything was going to be OK."

Dr Edmonds — who holds a PhD from Griffith University's Australian Rivers Institute — is a co-founder of Australian Parents for Climate Action, a national volunteer campaign group.

She has two young daughters and like many young parents, manages sleep deprivation and parenting stress with all of her other responsibilities at work and with friends.

Over the last year she's noticed another kind of pressure weighing on her — climate anxiety.

Dr Edmonds takes her role as a climate advocate seriously. ( Supplied: Heidi Edmonds )

This week the Australian Medical Association declared climate change a health emergency, referencing a higher incidence of mortality rates from heat stress and more mental ill health.

Ros Knight, the president of the country's peak body for psychologists, the Australian Psychological Society, says many Australians report some level of concern about climate change.

She points to a 2012 study that found 20 per cent of those surveyed felt climate-related distress at times.

"It's hard to be specific about exact numbers for climate anxiety with a capital 'A'," she says. "We would call it climate change distress — we wouldn't necessarily label it one particular response."

Her organisation has an online resource dedicated to coping with this distress and lists fear, anger, guilt, shame, grief, loss and helplessness as associated emotions.

When the tearful episode happened, Dr Edmonds says she still wasn't sure how to talk to her children about climate change.

"You talk to them about nature and caring for nature, and I said to them: 'Mummy's working very, very hard to protect the frogs and the fish and nature.'"

Balancing concern and positivity is part of a long-term strategy for Dr Edmonds, who says that with the support of family and her community, she focuses on solutions.

Another element in her arsenal of hope is the philosophical idea of eternalism.

A salve for a social affliction

Dr Edmonds first came across a passage in a self-help book that incorporated eternalism over a decade ago — and says it has stuck with her since then.

"If we think about time as a tapestry, it allows us to focus on giving our children bright moments now ... so that no matter what the future holds, they'll have had these wonderful moments," she says.

This reference to a tapestry of time resonates with eternalism — a theory that joins the past, present and future in a single block of time.

Kristie Miller, the joint director of the Centre for Time at Sydney University, uses the idea of a Persian rug to explain the concept.

Eternalism compares time to a tapestry, in which the past, present and future are all situated together. ( Getty: Dan Kitwood )

When you look down at a rug, she says, "you can see the whole thing".

"None of the rug is any more special than any other bit of the rug. The whole thing creates the entire picture, which is the universe."

So a person's life in 2019 doesn't take precedence over another person's life in 1519 — because there is no objective present moment.

Empowering or disempowering?

Dr Miller explains that eternalism can be a comfort when it comes to grief.

"It's true, of course, that your life comes to an end — in the sense that there will be later times when you don't exist," she says.

But from an eternalist perspective, she says, "all of your life is still out there in space time, so all the things that you did still exist. And some people find that quite consoling."

Dr Miller says eternalism can be either empowering or disempowering for people suffering climate anxiety. ( Supplied: Kristie Miller )

The situation becomes more complex in relation to climate change, because this grief is for a future that hasn't happened yet.

On the other hand, eternalism can also exacerbate climate grief — because people can "feel fairly sure that the future that's out there is suboptimal", Dr Miller says.

So does that mean the future is already set and there's no point in taking climate action now?

Not exactly, says Dr Miller, who uses the metaphor of a Rubik's cube to explain cause and effect in eternalism. "When you twist one bit around, other bits automatically twist in response," she says.

If the past, present and future of our world were a single Rubik's cube, and we wiggled certain elements like carbon emissions now, "what you'll do is you'll wiggle the way the future is".

"The later states depend in various ways on the earliest states," Dr Miller says.

This is where optimism comes into the equation.

Change takes time

Dr Edmonds says 90 per cent of the time she feels quite hopeful. "I remain focused on hoping that I can be part of the solution to give [my children] a healthy, happy future."

To maintain perspective, she separates the sources of her anxiety, asking which parts are climate anxiety, which are "just general parenting anxiety", and which are caused by a lack of sleep.

Ms Knight says this cognitive strategy is helpful because it prevents catastrophising.

"It's about being aware of what you can and can't contribute. So you can't change everything yourself," she says.

Psychologists recommend being mindful that changes in attitudes take time, and one person can't do everything. ( Getty: picture alliance )

She says maintaining positivity requires long-term thinking and relying on your community to help shoulder the effort of climate change advocacy.

And she recommends "keeping things in measure" and "realising that change does take time. And that, if we look around, we can see that change is slowly escalating."

Dr Edmonds says she's also taking action to get her work-life balance under control.

For her, that's all part of maintaining the pattern in the collective tapestry of time.