Before and after: see how bushfire and rain turned the Macquarie perch’s home to sludge



Mannus Creek in NSW during the 2020 bushfire period.
Luke Pearce, Author provided

Lee Baumgartner, Charles Sturt University; Katie Doyle, Charles Sturt University; Luiz G M Silva, Charles Sturt University; Luke Pearce, and Nathan Ning, Charles Sturt University

This article is a preview of Flora, Fauna, Fire, a multimedia project launching on Monday July 13. The project tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Sign up to The Conversation’s newsletter for updates.


The unprecedented intensity and scale of Australia’s recent bushfires left a trail of destruction across Australia. Millions of hectares burned and more than a billion animals were affected or died. When the rains finally arrived, the situation for many fish species went from dangerous to catastrophic.

A slurry of ash and mud washed into waterways, turning freshwater systems brown and sludgy. Oxygen levels plummeted and water quality deteriorated rapidly.

Hundreds of thousands of fish suffocated. It was akin to filling your fish tank with mud and expecting your goldfish to survive.

Take, for example, the plight of the endangered Macquarie perch (Macquaria australasica), an Australian native freshwater fish of the Murray-Darling river system.

A Macquarie perch.
Luke Pearce, Author provided



Read more:
Fish kills and undrinkable water: here’s what to expect for the Murray Darling this summer


A special fish

Macquarie perch were once one of the most abundant fish in the Murray-Darling Basin. Revered by the community and once responsible for supporting extensive Indigenous, recreational, commercial and subsistence fisheries, they are an iconic species found nowhere else in the world. However, they have very specific needs.

Macquarie perch like rocky river sections with clear, fast-flowing water, shaded by trees and bushes on the banks.

Massive change wrought on our rivers over the past century means Macquarie perch are now only found at a handful of locations in the Murray-Darling Basin.

One habitat – Mannus Creek near the NSW Snowy Mountains – is particularly special because it was relatively pristine before the fires. In fact, this creek contained the last population of the threatened Macquarie perch in the NSW Murray catchment. A study in 2017 found a Macquarie perch population that was restricted to a 9km section of the creek but was doing quite well.

That was until bushfire rapidly swept through the catchment in January this year.

Some of us visited the creek three weeks after the fires. The intensity, ferocity and speed of the fires meant nothing was spared. The former forest floor was literally a trail of death and destruction – dead and charred kangaroos, wallabies, deer, possums and birds were everywhere.

All that remained of Mannus Creek was green pools in a blackened landscape, still smouldering days after the fire front passed. We immediately feared for the Macquarie perch we’d sampled, which were quite healthy less than a year before.

To our surprise, some Macquarie perch had survived. But with most of the catchment fully burnt, and no vegetation to stop runoff, we knew it was a ticking time bomb.

A desperate rescue attempt

With little time, we had to remove as many fish as possible from Mannus Creek before the rains arrived. The plan was to create an “insurance population” in case rain caused the water conditions to deteriorate.

We rescued ten fish. Days later, rain washed ash and silt into the channel. Within hours, the once-pristine creek became flowing mud with the consistency of cake mix.

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A government rescue team arrived a few days later to rescue more fish, and despaired at the “wall of ash and mud”.

An ark across Australia

Those ten individual Macquarie perch now live in an “ark” of at-risk species, spanning government and private hatchery facilities.

The ark is housing not only the Macquarie perch but other threatened species too. The rescued individuals, and perhaps their entire species, would have almost certainly perished during runoff events without these interventions.

Now a waiting game begins.

What next for the Macquarie perch?

Nobody knows for sure how many fish survived in Mannus Creek, nor how long it will take for the creek to recover. It could be years.

Ash and mud flow into Lake Macquarie after the fires.
Luke Pearce, Author provided

The challenge now is to support the rescued fish until it’s safe to either return them to the creek, or breed offspring and introduce them to their natural habitat.

Fish must be kept healthy and disease-free in captivity, and enough genetic diversity must be maintained for the population to remain viable.

If these rescued fish are held in captivity for too long, they might die. But equally worrying is that affected waterways may not recover in time to allow reintroduction.




Read more:
Sure, save furry animals after the bushfires – but our river creatures are suffering too


While maintaining the rescued populations, we must redouble our efforts to improve their natural habitats.

Burnt areas can allow pest plant and animal species to take hold and change habitats, so these threats need to be controlled. Finding similar, unburnt refuge areas is also crucial to prepare for future events and protect ecosystem resilience.

Working through these considerations – and quickly – is essential to giving these species the best hope of survival.

Funding, equipment and human resources are desperately needed to help our rivers recover. But we know that without an effective on-ground intervention, recovery could take decades.

For the iconic Macquarie perch, that would be too late.




Read more:
The sweet relief of rain after bushfires threatens disaster for our rivers


The Conversation


Lee Baumgartner, Professor of Fisheries and River Management, Institute for Land, Water, and Society, Charles Sturt University; Katie Doyle, Freshwater Ecologist, Charles Sturt University; Luiz G M Silva, Freshwater Fish Scientist, Charles Sturt University; Luke Pearce, Fisheries Manager, and Nathan Ning, Freshwater Ecologist, Charles Sturt University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Birdwatching increased tenfold last lockdown. Don’t stop, it’s a huge help for bushfire recovery



Shutterstock

Ayesha Tulloch, University of Sydney; April Reside, The University of Queensland; Georgia Garrard, RMIT University; Michelle Ward, The University of Queensland, and Monica Awasthy, Griffith University

Many Victorians returning to stage three lockdown will be looking for ways to pass the hours at home. And some will be turning to birdwatching.

When Australians first went into lockdown in March, the combination of border closures, lockdowns and the closure of burnt areas from last summer’s bushfires meant those who would have travelled far and wide to watch their favourite birds, instead stayed home.

Yet, Australians are reporting bird sightings at record rates – they’ve just changed where and how they do it.

In fact, Australian citizen scientists submitted ten times the number of backyard bird surveys to BirdLife Australia’s Birdata app in April compared with the same time last year, according to BirdLife Australia’s Dr Holly Parsons.

But it’s not just a joyful hobby. Australia’s growing fascination with birds is vital for conservation after last summer’s devastating bushfires reduced many habitats to ash.

Birds threatened with extinction

Australia’s native plants and animals are on the slow path to recovery after the devastating fires last summer. In our research that’s soon to be published, we found the fires razed forests, grasslands and woodlands considered habitat for 832 species of native vertebrate fauna. Of these, 45% are birds.

Some birds with the largest areas of burnt habitat are threatened with extinction, such as the southern rufous scrub-bird and the Kangaroo Island glossy black-cockatoo.

Government agencies and conservation NGOs are rolling out critical recovery actions.

But citizen scientists play an important role in recovery too, in the form of monitoring. This provides important data to inform biodiversity disaster research and management.

Record rates of birdwatching

Birdwatchers have recorded numerous iconic birds affected by the fires while observing COVID-19 restrictions. They’ve been recorded in urban parks and city edges, as well as in gardens and on farms.

In April 2020, survey numbers in BirdLife Australia’s Birds in Backyards program jumped to 2,242 – a tenfold increase from 241 in April 2019.

Change in the number of area-based surveys by Australian citizen scientists over the first six months of 2019 compared with 2020. Data sourced from BirdLife Australia’s Birdata database.

Similarly, reporting of iconic birds impacted by the recent bushfires has increased.

Between January and June, photos and records of gang-gang cockatoos in the global amateur citizen science app iNaturalist increased by 60% from 2019 to 2020. And the number of different people submitting these records doubled from 26 in 2019 to 53 in 2020.




Read more:
Want to help save wildlife after the fires? You can do it in your own backyard


What’s more, reporting of gang-gangs almost doubled in birding-focused apps, such as Birdlife Australia’s Birdata, which recently added a bushfire assessment tool .

The huge rise in birdwatching at home has even given rise to new hashtags you can follow, such as #BirdingatHome on Twitter, and #CuppaWithTheBirds on Instagram.

A gang-gang effort: why we’re desperate for citizen scientists

The increased reporting rates of fire-affected birds is good news, as it means many birds are surviving despite losing their home. But they’re not out of the woods yet.

Their presence in marginal habitats within and at the edge of urban and severely burnt areas puts them more at risk. This includes threats from domestic cat and dog predation, starvation due to inadequate food supply, and stress-induced nest failure.

That’s why consolidating positive behaviour change, such as the rise in public engagement with birdwatching and reporting, is so important.

A female superb lyrebird calling to her reflection in a parked car in suburbia. Her nest was later discovered 100 meters from the carpark.

Citizen science programs help increase environmental awareness and concern. They also improve the data used to inform conservation management decisions, and inform biodiversity disaster management.

For example, improved knowledge about where birds go after fire destroys their preferred habitat will help conservation groups and state governments prioritise locations for recovery efforts. Such efforts include control of invasive predators, supplementary feeding and installation of nest boxes.

Gang gang Cockatoo hanging out on a street sign in Canberra.
Athena Georgiou/Birdlife Photography

Better understanding of how bushfire-affected birds use urban and peri-urban habitats will help governments with long-term planning that identifies and protects critical refuges from being cleared or degraded.

And new data on where birds retreat to after fires is invaluable for helping us understand and plan for future bushfire emergencies.

So what can you do to help?

If you have submitted a bird sighting or survey during lockdown, keep at it! If you have never done a bird survey before, but you see one of the priority birds earmarked for special recovery efforts, please report them.




Read more:
Six million hectares of threatened species habitat up in smoke


There are several tools available to the public for reporting and learning about birds.

iNaturalist asks you to share a photo or video or sound recording, and a community of experts identifies it for you.

BirdLife’s Birds in Backyards program includes a “Bird Finder” tool to help novice birders identify that bird sitting on the back verandah. Once you’ve figured out what you’re seeing, you can log your bird sightings to help out research and management.

The majority of habitat for Kangaroo Island glossy black cockatoos burnt last summer.
Bowerbirdaus/Wikimedia, CC BY-SA

For more advanced birders who can identify birds without guidance, options include eBird and BirdLife’s Birdata app. This will help direct conservation groups to places where help is most needed.

Finally, if there are fire-affected birds, such as lyrebirds and gang-gang cockatoos, in your area, it’s especially important to keep domestic dogs and cats indoors, and encourage neighbours to do the same. Report fox sightings to your local council.




Read more:
Lots of people want to help nature after the bushfires – we must seize the moment


If you come across a bird that’s injured or in distress, it’s best to contact a wildlife rescue organisation, such as Wildcare Australia (south-east Queensland), WIRES (NSW) or Wildlife Victoria.

By ensuring their homes are safe and by building a better bank of knowledge about where they seek refuge in times of need, we can all help Australia’s unique wildlife.The Conversation

Ayesha Tulloch, DECRA Research Fellow, University of Sydney; April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland; Georgia Garrard, Senior Research Fellow, Interdisciplinary Conservation Science Research Group, RMIT University; Michelle Ward, PhD Candidate, The University of Queensland, and Monica Awasthy, Visiting Research Scientist, Environmental Futures Research Institute, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Our field cameras melted in the bushfires. When we opened them, the results were startling



Taronga Zoo

Benjamin Scheele, Australian National University; David Newell, Southern Cross University; Jodi Rowley, Australian Museum, and Michael McFadden, University of Wollongong

This article is a preview of Flora, Fauna, Fire, a multimedia project launching on Monday July 13. The project tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Sign up to The Conversation’s newsletter for updates.


In late summer, male northern corroboree frogs call for a female mate. It’s a good time to survey their numbers: simply call out “Hey, frog!” in a low, deep voice and the males call back.

This year, the survey was vital. Bushfires had torn through the habitat of the critically endangered species. We urgently needed to know how many survived.

In late February we trekked into Kosciuszko National Park, through a landscape left charred by the ferocious Dunns Road fire.

We surveyed the scene, calling out: “Hey, frog!”. At ponds not severely burnt, reasonable numbers of northern corroboree frogs responded. At badly burnt sites where frogs had been found for 20 years, we were met with silence. The adults there had likely died.

After completing our surveys we collected melted cameras we’d deployed eight months earlier to monitor water levels in the ponds. Some weeks later, these would reveal just what the frogs had endured.

Northern corroboree frog on burnt moss after the fires.
Ben Scheele

A tiny frog with a big problem

Northern corroboree frogs are tiny – no longer than three centimetres long – and feature distinctive yellow and black stripes. They are listed as critically endangered, but are more abundant than their close relative, the southern corroboree frog.

They’re found only in the high country of southern New South Wales and the ACT. Before last summer’s bushfires, just a few thousand northern corroboree frogs were thought to remain in the wild. Our preliminary post-fire assessment indicates a substantial number might have died where fires were severe.

Caught on camera

Of the frogs’ two key habitat areas in NSW, one was burnt by the fires and one was left untouched. Over the border in the ACT, the fire damage was relatively slight, but the worst came later.

Heavy rain after the fires filled ponds with ash and sediment.
Ben Scheele

After the fires, heavy rain in denuded burnt catchments produced water runoff laden with sediment. Some frog breeding habitat was eroded and filled with silt and ash. Once-mossy ponds were now gravel and ash.

In March 2019, we’d set up cameras to take one photograph a day, to monitor water levels in ponds. The fires melted the cameras, and some were also waterlogged. One of the authors, Ben Scheele, took them home and left them in his garage, assuming the footage was lost.

But several weeks later, bored during the COVID-19 lockdowns, he chiselled open the warped casing and removed the memory cards. Amazingly, most still worked.

They contained a fascinating series of photos. Some revealed how a number of ponds largely escaped the fires, only to be destroyed afterwards by flooding.

The series below shows a pond in Kosciuszko National Park. Watch the transition from autumn to deep winter snow, then to dry earth before the fire and its smoky aftermath (when the camera had fallen to the ground):

A frog emergency

Australia is home to around 240 frog species, most found nowhere else in the world.

The expert panel advising the federal government on bushfire recovery has identified 16 frog species likely to be severely affected by last summer’s fires.

All but one was listed as threatened by the IUCN prior to the fires. Importantly, the panel noted not much is known about how Australian frogs respond to fire.

Many Australian frog species have adapted to survive fire. But last summer, fires tore through areas where such events are extremely rare.




Read more:
After the bushfires, we helped choose the animals and plants in most need. Here’s how we did it


This includes World Heritage rainforests in northern NSW, home to the mountain frog, found nowhere else on Earth. How these frogs will respond to the fires remains to be seen.

For species associated with streams, such as the Barred River frogs, the impacts of fire may not be immediately apparent. Males typically stay near streams and may have escaped the flames, but females spend much time away from streams and may have died. These frogs are long-lived, so it may be many years before population declines are detected.

A stuttering frog after a fire in Gibraltar Range National Park last summer.
Jodi Rowley

A shared fate

The effects of last summer’s fires on frogs are likely to be felt for years to come. For example, regrowing forests use lots of water, which will affect species in forested areas such as the northern corroboree frogs. This compounds a trend towards less rainfall under climate change, which is already driving their decline.

Annual northern corroboree frog monitoring conducted under the NSW government’s Saving Our Species program has been in place since 1998. This, coupled with the fact about half the known sites were fire-affected, puts us in a good position to better understand the species’ responses to fire by comparing burnt and unburnt sites in coming years.




Read more:
Yes, the Australian bush is recovering from bushfires – but it may never be the same


The NSW government’s Saving Our Species program, and Taronga Conservation Society Australia, have started work on a captive “assurance” population for the species. The project, supported by Commonwealth funding, involves collecting eggs from the wild to safeguard the species’ unique genetic diversity.

Ongoing monitoring of other frog species is also critical. Importantly, anyone can get involved in helping understand frog responses to fire through the FrogID app.

Habitat degradation, climate change and disease threaten frogs globally. In this, they have much in common with humans. Last summer’s severe fires were a direct result of climate change. And of course, COVID-19 has killed more than 500,000 people in recent months.

Perhaps humanity should reflect on the fate we share with wildlife, and act.

David Hunter of the NSW Department of Planning, Industry and Environment contributed to this article.The Conversation

Benjamin Scheele, Research Fellow in Ecology, Australian National University; David Newell, Senior Lecturer, School of Environment, Science & Engineering, Southern Cross University; Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum, and Michael McFadden, PhD Candidate, University of Wollongong

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why going camping could be the answer to your lockdown holiday woes



Pexels

Carol Southall, Staffordshire University

For many of us, the forced confinement of lockdown has reiterated the importance of being out and about in nature – along with the benefits it can bring.

So as the UK begins to reopen, it’s likely that many people will be craving space away from crowds and busy, built-up areas. And given that, one in eight British households has no garden, there is likely to be a surge in people heading off to enjoy the great outdoors and British countryside.

Indeed, outdoor areas and activities – think gardens, national parks and coastal areas – are likely to be busier than usual. Predominantly indoor activities and venues, meanwhile – such as restaurants, museums and galleries – are likely to face lengthier periods of subdued demand.

As a result, the tourism industry is anticipating a surge in people taking active outdoor breaks close to home. In the US for example, a national marketing campaign from the National Park Foundation will promote lesser-known parks as destinations. While Airbnb’s recent Go Near initiative aims to support the “growing desire for domestic travel”.

In the UK, VisitBritain’s weekly UK COVID-19 Consumer Tracker Report shows that 20% of adults in the UK plan to take a short break or holiday within the UK by September. Coastal areas (both urban and rural) are emerging as top destinations.

Heading outdoors

Spending time outdoors, can improve your blood pressure and digestion and boost the immune system. Spending time in green space, near trees, also means that we take in more oxygen, which in turn leads to release of the feelgood hormone serotonin.

Spending time outdoors can give you that natural boost.
DisobeyArt/Shutterstock

Many families incorporate outdoor activity in green space into their holiday plans as a way of improving wellbeing and mental health. Active pursuits in the outdoors can also bring families together to enjoy themselves.

Camping, more than most forms of holiday, involves family members doing more together and encourages a more active, back-to-nature lifestyle. And, according to research from the University of Plymouth, children who go camping do better at school and are healthier and happier. So it’s a win-win.

The children who took part in the research were asked what they love about camping and the most common themes were making and meeting new friends, having fun, playing outside and learning various camping skills. Children also recognised camping’s value for problem solving and working together – out in the fresh air, away from the TV and computers.

Quality family time

The make-up of family units has changed massively over the past two decades. And many families now live spread out – no longer in one place, town or city. So for many families, holidays offer the offer the chance to spend time and reconnect with different generations of their family – along with quality time together that is so fundamental to family life.

Time outdoors can give families the chance to reconnect.
Shutterstock/Maksym Gorpenyuk

For families with busy lives, where parents are often working long hours, the chance to be together on holiday can feel key to the survival of the family unit. And many working parents – mums in particular – have found that the struggle to balance work and childcare has been exacerbated during lockdown.

But of course, families struggling to spend time together is not a new phenomenon. In 2011 a Thomson Holiday report found that, more than one-quarter of working parents spent less than an hour a day with their children. This is despite wanting more time together.

Time for a break

The benefits of family holidays are numerous. They can give all members of the family time to regain balance, reconnect and restore equilibrium. Holidays are also often an opportunity for people to try new skills, sports or activities – which can help to boost confidence and self-esteem.

So don’t despair if you’re no longer heading abroad this summer. Instead, head for the great outdoors and enjoy some quality family time – away from the house and daily lockdown routine.

This will not only give you a chance to relax and unwind in a new environment but will also encourage children and other family members to try something new – whether it’s toasting marshmallows and singing campfire songs, swimming in rivers, stargazing – or simply just being close to nature.The Conversation

Carol Southall, Course Leader and Senior Lecturer at Staffordshire Business School, Staffordshire University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

After last summer’s fires, the bell tolls for Australia’s endangered mountain bells



Darwinia nubigena also known as the Success Bell or Red Mountain Bell.
A.T Morphet, Author provided

Kingsley Dixon, Curtin University

This article is a preview from Flora, Fauna, Fire, a multimedia project launching on Monday July 13. The project tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Sign up to The Conversation’s newsletter for updates.


Hidden in the Stirling Range national park in Western Australia – an area so diverse, so ecologically important, I’ve described it as a “coral reef out of water” – are Australia’s spectacular mountain bells.

When Western botanists encountered these predominantly bird-pollinated plants, they found them so intriguing and so unlike anything they knew (Britain has no bird pollination), they named them Darwinia after Charles Darwin’s grandfather, Erasmus Darwin.

These breathtaking native Australian flowers are now at grave risk from recent fires, with many species listed on the government’s provisional list of plants requiring urgent management intervention. The Stirling Ranges were ravaged by this summer’s fires, and three-quarters of this WA national park now experience fire cycles twice as frequent as species recovery rates.

If it sounds grim, that’s because it is. There’s hope yet for the mountain bell, though, thanks largely to the efforts of concerned community members.

Darwinia collina, the yellow mountain bell, is listed as endangered.
A. T. Morphet, Author provided

Why are mountain bells so special?

With an astonishing range of colours, the Stirling Range mountain bells are the glamour plants in WA’s floral bouquet.

Standing up to 60cm tall, these glorious shrubs are a gardener’s dream. They have neat foliage and pendulous, bell-like flowers in colours ranging from yellow, to greens, to striking reds and multicoloured variegated blooms.

Darwinia has just 70 species – a modest number compared with some plant genera in Australia.

They occur in southeastern and southwestern Australia. Darwinia split from their ancestral lineage 16 million years ago with the southwest, including the Stirling Ranges – a cradle of the genus. The chance dispersal of seed to southeastern Australia meant the two nodes of diversity were separated by the Nullarbor and central desert, and evolved in splendid isolation. How these heavy-seeded plants managed such an epic journey across the Australian deserts remains a mystery.




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The phoenix factor: what home gardeners can learn from nature’s rebirth after fire


Nectar-hungry Australian birds found the rewards in the rain-protected, bell-like flowers irresistible.

In what was a blink of evolutionary time, mountain bells capitalised on birds as a better system for pollination than offered by insects, and new species appeared across the peaks of the Stirlings.

Today, there are ten species of mountain bells. All but one are only found in the Stirling Ranges, often on single peaks or in highly restricted locations. And many feature on the provisional list of plants requiring urgent management.

Virtually each peak could have its very own mountain bell. I recall my first encounter with the mountain bells years ago. I’d spotted the delicate cherry-coloured blooms of Wittwer’s bell nestled in a small wooded hollow, midway along the main drive through the Stirlings. I eagerly sought out other mountain bell species and, soon enough, realised I had an untreatable case of “bell fever”.

A _Darwinia macrostegia or Mondurup Bell on Mondurup Peak.
A.T Morphet, Author provided

A biodiversity hotspot at a crossroads

Traditional owners revered the Stirling Ranges as sacred land that had endured countless ice ages and climate ravages. But today, the Stirling Ranges are at a crossroads.

The discovery of dieback disease (Phytophthora cinnamomi) in 1974, as well as fires both prescribed and natural, have taken a heavy toll on the plants and animals in the park.

Last summer’s cataclysmic fires scorched half of the Stirling Ranges national park, and the danger the mountain bells now face is emblematic of the broader problem of biodiversity loss.

Many plants and animal species here may never recover. Yes, many Australian plants evolved to cope with bushfire – but not with how frequently these fires are reoccurring.

The Stirling Ranges national park is like no other, with an astonishing 1,500 plant species, eclipsing the flora of the British Isles.

Threats abound

Contemporary fire is now one of the single greatest threats to what remains of this extraordinary ecosystem.

The mountain bells need more than 15 years or more to rebuild their soil seed bank, as these plants are killed by even the mildest of fire.

We knew this was coming. Dire predictions by conservation scientists as early as 2015 warned the Stirling Ranges faced a biodiversity meltdown, and that mountain bells were particularly at risk of extinction.




Read more:
After the bushfires, we helped choose the animals and plants in most need. Here’s how we did it


Though the fires have retreated, the once thriving populations of mountain bells are reduced to blackened stems. It is indescribably sad to see.

For some species, the 2020 bushfires came hot on the heels of an out-of-control prescribed burn in 2018, and few species can survive such short interval fire. Scientists are surveying the damage, to see if parts of the soil seed bank survived to grow the next generation of mountain bells. But it may be too late for some species. Time will tell.

The endemic grass tree Kingia australis absorbs ethylene gas from bushfire to initiate flowering within months.
Keith Bradbury, Author provided

Community action

Is there a future for mountain bells? I like to think so. I have grown them in wildflower gardens from cuttings handed down from wildflower gardeners over decades. Through temperamental and often unpredictable to grow, mountain bells are remarkably easy to propagate.

A key part of saving our mountain bells is, I believe, intimately linked to the community of wildflower enthusiasts. These passionate, committed community members stand ready to help save the last bells.

The Stirling Ranges national park in Western Australia.
Trevor Dobson, CC BY-NC-ND

The way we’ve done conservation in the past needs a reboot. For the mountain bells and many other threatened species to have a future, we need to embrace a new way of engaging with community volunteers and particularly our traditional owners.

Everyone I have spoken to is ready to roll up their sleeves and help our plants, and animals struggling to come out of the fires. Such an approach will need trust, training and support – but it may be our only hope.




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The Conversation


Kingsley Dixon, John Curtin Distinguished Professor, Curtin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Intensive farming is eating up the Australian continent – but there’s another way



Sue McIntyre, Author provided

Sue McIntyre, Australian National University

Last week we learned woody vegetation in New South Wales is being cleared at more than double the rate of the previous decade – and agriculture was responsible for more than half the destruction.

Farming now covers 58% of Australia, or 385 million hectares, and accounts for 59% of water extracted.

It’s painfully clear nature is buckling under the weight of farming’s demands. In the past decade, the federal government has listed ten ecological communities as endangered, or critically endangered, as a result of farming development and practices.

So how can we accommodate the needs of both farming and nature? Research shows us how – but it means accepting land as a finite resource, and operating within its limits. In doing so, farmers will also reap benefits.

Grassy eucalypt woodlands used for cattle farming in subtropical Queensland.
Tara Martin. Author provided.

Healthy grazing landscapes

In the 1990s, I worked as a research ecologist in the cattle country of sub-tropical Queensland. The prevailing culture valued agricultural development over conservation. Yet many of these producers lived on viable farms that supported a wealth of native plants and animals.

They made a living from the native grassy eucalypt woodlands, an ecosystem that extends from Cape York to Tasmania. In these healthy landscapes, vigorous pastures of tall perennial grasses protected the soil, enriched it with carbon and fed the cattle.




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IPCC’s land report shows the problem with farming based around oil, not soil


NSW and Victoria have similar eucalypt grassy vegetation, but farming here has taken a very different path.

Fertilised legumes and grasses grown for livestock fodder have replaced hundreds of native grassland plants. Over time, native trees and shrubs stopped regenerating and remaining trees became unhealthy, destroying wildlife habitat. The transformation was hastened by aerial applications of fertiliser and herbicide.

By 2006, 4.5 million hectares of box-gum grassy woodland – or 90% – in temperate Australia had been destroyed.

Aerial delivery of fertiliser, seed and herbicide transformed grassy woodlands in NSW.
F. G. Swain. Author provided.

A template for sustainability

Back in Queensland in the 1990s, my colleagues and I devised a template for sustainable land use. Funded by the livestock industry and a now-defunct federal corporation, we worked with producers and government agencies to find the right balance between farm production and conserving natural resources.

Our research concluded that for farming to be sustainable, intensive land uses must be limited. Such intensive uses include crops and non-native pastures. They are “high input”, typically requiring fertilisers, herbicides and pesticides, and some form of cultivation. They return greater yields but kill native plants, and are prone to soil and nutrient runoff into waterways.

But our template was not adopted as conventional farming practice. In the past 20 years, Australia’s cropping area has increased by 18,200 square kilometres.

By 2019, 38,000 square kilometres of poplar box grassy woodland in Australia had been cleared – more than half the size of Tasmania. The ecosystem was listed as endangered in 2019. Until that point, it had been considered invasive native scrub in NSW – exempting it from clearing regulations – and was systematically cleared for agriculture in Queensland.

Farmers should conserve sufficient areas of landscape to support native plants and animals.
Sue McIntyre, Author provided

Regenerating the land

Hearteningly, our research was recently revived in a multidisciplinary study of regenerative grazing on the grassy woodlands of NSW. The template was used to assess the ecological condition of participating farms.

The study examined differences in profitability between graziers who had adopted regenerative techniques such as low-input pasture management, and all other sheep, sheep-beef and mixed cropping-grazing farmers in their region.




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It found regenerative grazing was often more profitable than other types of farming, especially in dry years. Regenerative farmers also experienced significantly higher than average well-being compared with other NSW farmers.

So what does our template involve? First, it identifies four types of land use relevant to farmed grassy woodland regions.

Second, it specifies the proportion of land that should be allocated to each use, in order to achieve landscape health (see pie chart below). The proportions can be applied to single farm, or entire districts or regions.

How to sustain production, natural resources and native flora and fauna on a landscape or farm.
Sue McIntyre

Intensive land use involves activities that replace nearly all native species. If these activities occupy more than 30% of the landscape, there’s insufficient habitat to maintain many native species, especially plants.

At least 10% of land must be devoted to nature conservation. The remaining 60% of the land should involve low-intensity activity such as grazed native pasture and timber production. If managed well, these land uses can support human livelihoods and a diversity of native species.

Within that split of land use, total native woodland should be no less than 30%. This guarantees connected habitats for native plants and animals, enabling movement and breeding opportunities.

Retaining grassy woodland ensures habitat for native animals.
Duncan McCaskill/Flickr

Respect the land’s limits

Australians ask a lot of our land. It must make space for our houses, businesses, and roads. It should support all species to prevent extinctions. And it must produce our food and fibre.

Global population growth demands a rapid rise in food production. But relying on intensive agriculture to achieve this is unsustainable. Aside from damaging the land, it increases greenhouse gas emissions though mechanisation, fertilisation, chemical use and tree clearing.




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Australian farmers are adapting to climate change


To meet the challenges of the future we must ensure farmed landscapes retain their ecological functions. In particular, maintaining biodiversity is key to climate adaptation. And as many of Australia’s plants and animals march towards extinction, the need to reverse biodiversity loss has never been greater.

Farmers can be profitable while maintaining and improving the ecological health of their land. It’s time to look harder at farming models that respect the limits of nature, and recognise that less can be more.The Conversation

Sue McIntyre, Honorary Professor, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Extreme heat and rain: thousands of weather stations show there’s now more of both, for longer



ChameleonsEye/Shutterstock

Jim Salinger, University of Tasmania and Lisa Alexander, UNSW

A major global update based on data from more than 36,000 weather stations around the world confirms that, as the planet continues to warm, extreme weather events such as heatwaves and heavy rainfall are now more frequent, more intense, and longer.

The research is based on a dataset known as HadEX and analyses 29 indices of weather extremes, including the number of days above 25℃ or below 0℃, and consecutive dry days with less than 1mm of rain. This latest update compares the three decades between 1981 and 2010 to the 30 years prior, between 1951 and 1980.

Globally, the clearest index shows an increase in the number of above-average warm days.


Author provided

For Australia, the team found a country-wide increase in warm temperature extremes and heatwaves and a decrease in cold temperature extremes such as the coldest nights. Broadly speaking, rainfall extremes have increased in the west and decreased in the east, but trends vary by season.

In New Zealand, temperate regions experience significantly more summer days and northern parts of the country are now frost-free.




Read more:
The world endured 2 extra heatwave days per decade since 1950 – but the worst is yet to come


Extreme temperatures

Unusually warm days are becoming more common throughout Australia. When we compare 1981-2010 with 1951-80, the increase is substantial: more than 20 days per year in the far north of Australia, and at least 10 days per year in most areas apart from the south coast. The increase occurs in all seasons but is largest in spring.

This increase in temperature extremes can have devastating impacts for human health, particularly for older people and those with pre-existing medical conditions. Excessive heat is not only an issue for people living in cities but also for rural communities that have already been exposed to days with temperatures above 50℃.

New Zealanders are also experiencing more days with temperatures of 25℃ or more. The climate stations show the frequency of unusually warm days has increased from 8% to 12% from 1950 to 2018, with an average of 19 to 24 days a year above 25℃ across the country. Unusually warm days, defined as days in the top 10% of historic records for the time of year, are also becoming more common in both countries.

During the summers of 2017-18 and 2018-19, marine heatwaves delivered 32 and 26 (respectively) days above 25℃ nationwide in New Zealand, well above the average of 20 days. This led to accelerated glacial melting in the Southern Alps and major disruption to marine ecosystems, with die-offs of bull kelp around the South Island coast and salmon in aquaculture farms in the Marlborough Sounds.




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Farmed fish dying, grape harvest weeks early – just some of the effects of last summer’s heatwave in NZ


More heat, more rain, less frost

In many parts of New Zealand, cold extremes are changing faster than warm extremes.

Between 1950 and 2018, frost days (days below 0℃) have declined across New Zealand, particularly in northern parts of the country which has now become frost-free, enabling farmers to grow subtropical pasture grasses. At the same time, crops that require winter frosts to set fruit are no longer successful, or can only be grown with chemical treatments (currently under review) that simulate winter chilling.

Across New Zealand, the heat available for crop growth during the growing season is increasing, which means wine growers have to shift varieties further south.

In Australia, the situation is more complicated. In many parts of northern and eastern Australia, there has also been a large decrease in the number of cold nights. But in parts of southeast and southwest Australia, frost frequency has stabilised, or even increased in places, since the 1980s.

These areas have seen a large decrease in winter rainfall in recent decades. The higher number of dry, clear nights in winter, favourable for frost formation, has cancelled out the broader warming trend.




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Droughts & flooding rains: what is due to climate change?


In Australia, extreme rainfall has become more frequent in many parts of northern and western Australia, especially the northwest, which has become wetter since the 1960s. In eastern and southern Australia the picture is more mixed, with little change in the number of days with 10mm or more of rain, even in those regions where total rainfall has declined.

In New Zealand, more extremely wet days contribute towards the annual rainfall total in the east of the North Island, with a smaller increase in the west and south of the South Island. For Australia, there are significant drying trends in parts of the southwest and northeast, but little change elsewhere.

Extremes of temperature and precipitation can have dramatic effects, as seen during two marine heatwaves in New Zealand and the hottest, driest year in Australia during 2019.The Conversation

Jim Salinger, Honorary Associate, Tasmanian Institute for Agriculture, University of Tasmania and Lisa Alexander, Chief Investigator ARC Centre of Excellence for Climate System Science and Associate Professor Climate Change Research Centre, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Waste not, want not: Morrison government’s $1b recycling plan must include avoiding waste in the first place



Mick Tsikas/AAP

Trevor Thornton, Deakin University

The federal government today announced A$190 million in funding for new recycling infrastructure, as it seeks to divert more than ten million tonnes of waste from landfill and create 10,000 jobs.

The plan, dubbed the Recycling Modernisation Fund, requires matching funding from the states and territories. The federal government hopes it will attract A$600 million in private investment, bringing the total plan to about A$1 billion.

The policy is a welcome step to addressing Australia’s waste crisis. In 2016-17, Australians generated 67 million tonnes of waste, and the volume is growing.

Australia’s domestic recycling industry cannot sort the types and volumes of materials we generate, and recent waste import bans in other countries mean our waste often has nowhere to go.

But recycling infrastructure alone is not enough to solve Australia’s waste problem. We must also focus on waste avoidance, reducing contamination and creating markets for recycled materials.

Waste avoidance is even more important than recycling.
Mick Tsikas/AAP

A home-grown problem

In early 2018, China began restricting the import of recyclables from many countries, including Australia, arguing it was too contaminated to recycle. Several other countries including India and Taiwan soon followed.

The move sent the Australian waste management industry into a spin. Recyclable material such as plastic, paper, glass and tyres was stockpiled in warehouses or worse, dumped in landfill.




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It was clear Australia needed to start processing more of its waste onshore, and pressure was on governments to find a solution. In 2019, state and federal governments announced a waste export ban.

Then came today’s announcement. In addition to the A$190 million for recycling infrastructure announced, the federal government will:

  • spend A$35 million on meeting its commitments under the National Waste Policy Action Plan

  • spend A$24.6 million on Commonwealth commitments to improve national waste data and determine if we’re meeting recycling targets

  • introduce new federal waste legislation to formalise the waste export ban and encourage companies to take responsibility for the waste they create.

But key questions remain: will the full funding package be delivered, and will it be spent where it’s needed?

Overseas bans on foreign waste pose a problem for Australia.
Fully Handoko/EPA

Clarity is needed

The Commonwealth says its funding is contingent on contributions from industry, states and territories. It’s not clear what happens to the plan if this co-funding does not eventuate.

Figures from the Australian Council of Recyclers shows state governments have not always been willing to spend on waste management. Of about A$2.6 billion in waste levies collected from businesses and households over the past two years, only 16.7% has been spent on waste, recycling and resource recovery.

There’s been a recent increase in the volume and type of materials placed into recycling and waste streams. But a lack of funding to date meant the industry struggled to manage these changes.

Some state governments have recently made positive moves towards spending on waste management infrastructure, and it’s not clear what the federal plan means for these commitments. Victoria, for example, has a A$300 million plan to transform the recycling sector. Will it now be asked to spend more?

Recycling infrastructure is not enough

The federal announcement made no mention of the three other pillars in successful waste management: waste avoidance, reducing contamination and creating markets for recycled materials.

The 2018 National Waste Policy says waste “avoidance” is the first principle in waste management, stating:

Prioritise waste avoidance, encourage efficient use, reuse and repair. Design products so waste is minimised, they are made to last and we can more easily recover materials.

States have collected billions in waste levies, but spent little on the problem.
Dave Hunt/AAP

Avoiding the generation of waste in the first place reduces the need for recycling. Waste avoidance also means we consume less resources, which is good for the planet and our economy.

Addressing contamination in our recycling streams is also vital. Contaminants include soft plastics, disposable nappies and textiles. If these items end up in this stream, recyclers must remove and dispose of them, adding time and costs to the process.

Addressing the contamination issue would also reduce the amount of new infrastructure required.

Public education and enforcement is urgently needed to reduce recycling contamination and increase waste avoidance, yet government action has been lacking in this area.

Businesses have great potential to reduce costs associated with managing waste. This includes reducing the waste of raw materials as well as improving the segregation of wastes and recyclables. Funding is desperately needed to help businesses implement these changes.

The federal government says the new funding could be used for small, portable waste-sorting facilities. This is a great idea. They could be located in rural and regional areas, and even at large events so materials can be effectively sorted at the source. This would make sorting more efficient and may also reduce the need for waste transport.




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And of course, there’s no use producing recycled materials if no-one wants to buy them. Plenty of products could be produced using recycled glass, plastics, textiles and so on, but the practice in Australia is fairly limited. One promising example involves using glass and plastic in road bases.

Governments, business and even consumers can do more to demand that the products they buy contain a proportion of recycled materials, where its possible for a manufacturer to do so.

Why send material to landfill when it can be recycled?
AAP

A sustainable future

The government’s funding to improve waste data is welcome, and will allow improvements to the waste system to be accurately measured. Currently, many waste databases measure measure our recycling rate according to what goes into the recycling bins, rather than what actually ends up being recycled.

Spending to support actions under the National Waste Policy is also positive, as long as it spent primarily on reducing waste from being created in the first place.

Done right, better waste management can stimulate the economy and help improve the environment. Today’s announcement is a good step, but more detail is needed. Clearly though, it’s time for Australians to think more carefully about the materials we dispose of, and put them to better use.




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Recycling plastic bottles is good, but reusing them is better


The Conversation


Trevor Thornton, Lecturer, School of Life and Environmental Sciences, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

45,000 renewables jobs are Australia’s for the taking – but how many will go to coal workers?



Dan Himbrechts/AAP

Chris Briggs, University of Technology Sydney; Elsa Dominish, University of Technology Sydney, and Jay Rutovitz, University of Technology Sydney

As the global renewables transition accelerates, the future for coal regions has become a big worry. This raises an important question: can renewables create the right jobs in the right places to employ former coal workers?

According to our new research, the answer in many cases is “yes”. Renewable energy jobs provide a good match for existing coal jobs across a range of blue and white-collar occupations, including construction and project managers, engineers, electricians, site administrators and mechanical technicians.

But about one-third of coal workers, such as drillers and machine operators, cannot simply switch over to renewables jobs. So as our economy pivots to renewables, planning and investment is needed to help coal regions survive.

Some renewables jobs could be filled by coal workers.
Tim Wimbourne/AAP

Renewables jobs: a snapshot

Our research, commissioned by the Clean Energy Council, is the first large-scale survey of renewable energy employment in Australia.

We surveyed more than 450 Australian renewable energy businesses, covering large scale wind, solar and hydro, rooftop solar and batteries. We wanted to find out how many people were employed, and in what jobs.




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We then projected employment until 2035 using three scenarios for the future of the electricity market, developed by the Australian Energy Market Operator (AEMO).

Our results suggest renewable energy can be a major source of jobs in the next 15 years. But the trajectories are very different depending on government COVID-19 stimulus measures and wider energy policy.

Policy crossroads

We found the renewable energy sector currently employs about 26,000 people. Temporary construction and installation jobs now comprise 75% of the renewable energy labour market, but as the sector grows, this will change (more on that later).

Australia’s renewable energy target was reached last year, and has not been replaced. According to the Reserve Bank of Australia this caused renewables investment to fall by 50% last year compared to 2018. Under a “central” scenario where these policies continued, 11,000 renewable jobs would be lost by 2022.

Under the right policies, there could be an average of 35,000 renewables jobs annually in Australia until 2035.
Michael Buholzer/Reuters

We then examined a “step change” scenario where Australian policy settings were in line with meeting the Paris climate agreement. This would create a jobs boom: renewable energy employment would grow to 45,000 by 2025 and average around 35,000 jobs each year to 2035. Up to two-thirds are in regional areas.

Under all scenarios, job growth is strongest in rooftop solar and wind. Most are in the construction and installation phase, comprising both ongoing and project-based jobs in trades, as well as technicians and labourers. But by 2035, as many as half of renewable energy jobs could be ongoing jobs in operation and maintenance.




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Renewable energy jobs will be higher than our projections. We excluded employment areas such as building electricity transmission networks, bioenergy, professional services, renewable hydrogen, growth in minerals needed for renewable energy, and jobs in heavy industry such as “green” steel.

Renewables vs coal jobs

All up, coal mining in Australia employs about 40,000 people. As mentioned above, renewable energy jobs could grow to 45,000 by 2025 – and more once other sectors are included.

Australia’s renewable energy industry already employs considerably more people than the 10,500 working in the domestic coal sector – mostly thermal coal mining and power generation.

About 75% of coal mined in Australia is exported. About 24,000 people work in thermal coal mining for both domestic use and export – slightly fewer than the current renewable energy workforce.

Employment in renewable energy and coal.
Author supplied

New renewables jobs in coal regions

Around two-thirds of renewable energy jobs could be created in regional areas. These would be distributed more widely than coal sector jobs.

The leading coal mining states, NSW and Queensland, have the biggest share of renewable energy jobs under all scenarios.

AEMO has identified “renewable energy zones” where most large-scale renewable energy is expected to be located. In both NSW and Queensland, some of these zones overlap with the coal workforce. In NSW, the Central West zone could also create employment in the Hunter region. In general, though, many renewable energy jobs will be located in other regions and the capital cities.




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In terms of occupations, there is overlap between coal and renewable energy. These include construction and project managers, engineers, electricians, mechanical trades, office managers and contract administrators and drivers.

The timing and location of these renewables jobs will influence whether they can be a source of alternative jobs for coal workers. Re-training of coal workers would also be required.

But there is no direct job overlap for the semi-skilled machine operators such as drillers, which account for more than one-third of the coal workforce.

Renewable Energy Zones and coal mining employment in Queensland.
Author supplied
Renewable energy zones and coal mining employment in NSW.
Author supplied

Planning for the decline

Renewable energy can meaningfully help in the transition for coal regions. But it won’t replace all lost coal jobs, and planning and investment is needed to avoid social and economic harm.

Coal regions need industry development plans and investment to diversify their economies to other industries, including renewables. Almost half our coal workers are aged under 40, so Australia will not be able to follow Germany and Spain’s lead by relying on early retirement schemes.

At some point, demand for our coal exports will collapse – be it due to the falling cost of renewables, or policies to address climate change. If we don’t start preparing now, the consequences for coal communities will be dire.The Conversation

Some coal workers can be retrained to work in renewables, but others cannot.
Dan Himbrechts/AAP

Chris Briggs, Research Principal, Institute for Sustainable Futures, University of Technology Sydney; Elsa Dominish, Senior Research Consultant, Institute for Sustainable Futures, University of Technology Sydney, and Jay Rutovitz, Research Director, Institute for Sustainable Futures, University of Technology Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The world endured 2 extra heatwave days per decade since 1950 – but the worst is yet to come



Shutterstock

Sarah Perkins-Kirkpatrick, UNSW

The term “heatwave” is no stranger to Australians. Defined as when conditions are excessively hot for at least three days in a row, these extreme temperature events have always punctuated our climate.

With many of us in the thick of winter dreaming of warmer days, it’s important to remember how damaging heatwaves can be.

In 2009, the heatwave that preceded Black Saturday killed 374 people. The economic impact on Australia’s workforce from heatwaves is US$6.2 billion a year (almost AU$9 billion). And just last summer, extreme temperature records tumbled, contributing to Australia’s unprecedented bushfire season.

What are heatwaves?

Our new study – the first worldwide assessment of heatwaves at the regional scale – found heatwaves have become longer and more frequent since 1950. And worryingly, we found this trend has accelerated.

We also examined a new metric: “cumulative heat”. This measures how much extra heat a heatwave can contribute, and the new perspective is eye-opening.

What is ‘extra heat’?

In southeast Australia’s worst heatwave season in 2009, we endured an extra heat of 80℃. Let’s explore what that means.

For a day to qualify as being part of a heatwave, a recorded temperature should exceed an officially declared “heatwave threshold”.

And cumulative heat is generally when the temperature above that threshold across all heatwave days are added up.

Let’s say, for example, a particular location had a heatwave threshold of around 30℃. The “extra heat” on a day where temperatures reach 35℃ would be 5℃. If the heatwave lasted for three days, and all days reached 35℃, then the cumulative heat for that event would be 15℃.

Another decade, another heatwave day

We found almost every global region has experienced a significant increase in heatwave frequency since 1950. For example, southern Australia has experienced, on average, one extra heatwave day per decade since 1950.




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However, other regions have experienced much more rapid increases. The Mediterranean has seen approximately 2.5 more heatwave days per decade, while the Amazon rainforest has seen an extra 5.5 more heatwave days per decade since 1950.

The global average sits at approximately two extra heatwave days per decade.

The last 20 years saw the worst heatwave seasons

Since the 1950s, almost all regions experienced significant increases in the extra heat generated by heatwaves.

Over northern and southern Australia, the excess heat from heatwaves has increased by 2-3℃ per decade. This is similar to other regions, such as western North America, the Amazon and the global average.

Alaska, Brazil and West Asia, however, have cumulative heat trends of a massive 4-5℃ per decade. And, for the vast majority of the world, the worst seasons occurred in the last 20 years.

In the heatwave before Black Saturday, 374 people died.
Shutterstock

We also examined whether heatwaves were changing at a constant rate, or were speeding up or slowing down. With the exception of average intensity, we found heatwave trends have not only increased, but have accelerated since the 1950s.

Don’t be fooled by the maths

Interestingly, average heatwave intensity showed little – if any – changes since 1950. But before we all breathe a sigh of relief, this is not because climate change has stopped, or because heatwaves aren’t getting any warmer. It’s the result of a mathematical quirk.




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Since we’re seeing more heatwaves – which we found are also generally getting longer – there are more days to underpin the average intensity. While all heatwave days must exceed a relative extreme threshold, some days will exceed this threshold to a lesser extent than others. This brings the overall average down.

When we look at changes in cumulative heat, however, there’s just no denying it. Extra heat – not the average – experienced in almost all regions, is what can have adverse impacts on our health, infrastructure and ecosystems.

The Amazon has endured 5.5 more heatwave days per decade since 1950.
Shutterstock

Like nothing we’ve experienced before

While the devastating impacts of heatwaves are clear, it has been difficult to consistently measure changes in heatwaves across the globe. Previous studies have assessed regional heatwave trends, but data constraints and the spectrum of different heatwave metrics available have made it hard to compare regional changes in heatwaves.

Our study has closed this gap, and clearly shows heatwaves are on the rise. We are seeing more of them and they are generating more heat at an increasing pace.




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We’ve learned a lot about heatwaves, but we’re still just warming up


While Australia may be no stranger to heatwaves in the past, those we see in the future under these accelerating trends will certainly be foreign.

For example, a 2014 study found that depending on where you are in Australia, anywhere between 15 and 50 extra heatwave days will occur by 2100 compared to the second half of the 20th century.

We can still abate those trends if we work collectively, effectively and urgently to reduce our greenhouse gas emissions.The Conversation

Sarah Perkins-Kirkpatrick, ARC Future Fellow, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.