Our government has great aspirations. It has committed to end extinctions and expand our protected areas to cover 30% of every Australian ecosystem by 2030. This is part of its Nature Positive Plan, aligned with the 2022 Kunming-Montreal global biodiversity pact. The goal is not just to conserve nature but to restore what is being lost.

But how can these goals be reconciled with a budget that allocated more public money to carbon capture and storage than biodiversity?

This week’s federal budget was a new low point for investment in nature. Environmental groups roundly criticised the “bad budget for nature”, which delivered next-to-no money to protect and recover Australia’s unique and threatened biodiversity.

Research has shown Australians want at least 2% of the federal budget spent on nature. Instead, less than 0.1% of the budget spend will support biodiversity in some way. Over the past decade, biodiversity funding has gone down 25% relative to GDP.

Let’s say the government decided it was finally time to roll up the sleeves and do something. How would they go about it? What would it take to actually reverse the decline, as the government says it wants to in its Nature Positive approach?

Our threatened species populations have been declining by about 2-3% a year over the past 20 years. The first step is to stop the fall. Then the challenge is to restore dwindling species and ecosystems.

The Dow Jones for threatened species goes down, down, down

Australia now has a Threatened Species Index. Think of it like the Dow Jones for wildlife. It uses trend data from bird, mammal and plant species collected from over 10,000 sites to measure progress for nature in Australia.

Last year, Treasurer Jim Chalmers talked up the index as part of the first national “wellbeing budget”, which aimed to measure Australia’s progress across a range of social, health and sustainability indicators.

What does the index tell us? You can see for yourself. The health of our threatened species has fallen by about 2-3% a year since the turn of the century.

If, as is likely, the trend continues, it will lead to the extinction of many more of our unique native animals and plant species. It will signal the failure of the government’s Nature Positive policy and a global biodiversity tragedy.

Given we have had decades of successive decline, what would be needed to reach the goal of nature positive?

Nature positive actually has a very specific meaning. It would:

halt and reverse nature loss measured from a baseline of 2020, through increasing the health, abundance, diversity and resilience of species, populations and ecosystems so that by 2030 nature is visibly and measurably on the path of recovery.

This definition gives us a clear, measurable timeline for action, often described as nature’s answer to net zero.

To reach nature positive means halting biodiversity loss by 2030 so that in the future there is much more biodiversity, relative to a 2020 baseline.

What would that look like using the Threatened Species Index? To get on track with nature positive, we would have to stop the index declining, stabilise, and then increase from 2030 onwards.

Of course, strong environmental laws and aligned policies are needed to effectively prevent further loss of habitat.

But we also need to invest in restoring what has been lost. Scientists think this is possible with $2 billion a year to recover our most threatened native plants and animals, and another $2 billion annually to drive ecosystem restoration across Australia.

The budget is not nature positive

In the budget papers, the government uses the Threatened Species Index as a performance measure for its nature positive goal. It expects the trajectory of the index to be “maintained or improved” out to 2027-28.

But given our species and ecosystems are steadily declining, year after year, to maintain a trajectory is simply to embrace the decline. It’s not nature positive at all. The government could make minor improvements, slowing the collapse, and claim it was improving the lot of nature.

Imagine if our GDP growth was negative and the government’s goal was merely to slow its decline over the next five years – there would be national uproar.

If the government is serious about nature positive – which is an excellent goal – it would be setting more ambitious targets. For instance, the goal could be for the index to climb back up to 2020 levels by the end of the decade.

Instead, Labor is planning for biodiversity decline to continue, while describing it as “nature positive”.

Watching over the steady decline of our species and calling it nature positive makes about as much sense as opening up new gas fields and calling it net zero.

Greenwashing Nature Positive

Unfortunately, this is not the first time the government has engaged in nature positive greenwash.

In coming weeks, the government will introduce bills to parliament to establish two new agencies, Environment Information Australia and Environmental Protection Australia. But there will be one bill missing – the reformed federal environment laws, intended to give teeth to the nature positive push.

The laws were pushed back indefinitely, to the shock of scientists and environmental groups.

But let’s be generous and say these laws finally make it to parliament after the next election. Would they be enough to stop our species losses and put the Threatened Species Index onto a nature positive trajectory?

It’s unlikely.

The consultation documents show the government is aiming to deliver “net positive outcomes”, whereby development impacts to threatened species and ecosystems are more than compensated for.

But we don’t know the detail. How much improvement is the government aiming for? In the draft laws, this figure is listed simply as “at least X%”.

Time to aim higher

It is hard not to feel dispirited over the government’s backtracking on its promise to:

not shy away from difficult problems or accept environmental decline and extinction as inevitable.

But we cannot give up. As the plight of nature worsens, even iconic species such as the koala and platypus are now at risk. As ecosystems collapse, our food security, health and wellbeing, communities and businesses will suffer.

Perhaps one day we will have a government able to grasp the nettle and actually tackle the nature crisis – for the sake of all of us.

Megan C Evans, Senior Lecturer, Public Sector Management, School of Business, UNSW Sydney; Brendan Wintle, Professor in Conservation Science, School of Ecosystem and Forest Science, The University of Melbourne, and Hugh Possingham, Professor of Conservation Biology, The University of Queensland

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

Last night’s budget is another missed opportunity to arrest the poor and deteriorating state of the Australian environment.

Subsidising green industry in Labor’s Future Made in Australia policy may offer economic advantages if implemented well, but there is nothing in this budget to help address the immediate environmental crisis facing Australia.

The story so far

After being elected in 2022, Labor made a number of good promises. The new government legislated an emissions reduction target – a 43% cut by 2030 on 2005 figures and net zero by 2050. Last year, Labor reformed the Coalition’s only emissions monitoring program, the safeguard mechanism, to help deliver these reductions. (Recent research has cast doubt on the integrity of the system’s carbon credits). And the government signed an international biodiversity pact, which commits us to protect 30% of our land (currently at 22%) and halt biodiversity loss by 2030.

But Labor also promised to rewrite Australia’s main environment laws, the Environmental Protection and Biodiversity Conservation Act, which governs the protection of places and species, and approvals for significant projects. This was motivated by the horrendous bushfires in 2019–20 and a damning review, which found the laws were not up to the task of stopping environmental decline.

In the lead-up to tonight’s budget, Labor announced that the stronger laws had been indefinitely delayed. Instead, Australia would get a national environmental protection agency, Environment Protection Australia. While a strong and independent agency would improve compliance and monitoring, it will be enforcing ineffective laws until reforms are passed. Labor also shocked environmental groups by supporting a future for fossil gas, including opening up new gas fields.

Made in Australia

So if we’re not getting new environment laws, what is in the budget for the environment?

A whole lot for green industries. The 2024 budget’s centrepiece is the Future Made in Australia policy, a series of initiatives costing A$23 billion over ten years that focuses on subsidies for manufacturing industries including solar panels and green hydrogen.

Here, the Government is actively intervening in the market to push the economy towards specific ends – boosting green industries and making supply chains more resilient. As the budget papers state, one goal is to make Australia “an indispensable part of global net zero supply chains.”

In recent years western governments have embraced industrial subsidies, most notably seen in the CHIPS and Science Act and Inflation Reduction Act in the United States.

So what’s the government planning? Included in the announced package is:

$3.2 billion over ten years in additional funding to the Australian Renewable Energy Agency. This includes $1.7 billion in grants for innovation in green metals, low carbon liquid fuels, and batteries.

$1.7 billion over 10 years for an additional round of Hydrogen Headstart. This will fund the difference between the cost to produce renewable hydrogen and the current market price for eligible firms. Also planned is an additional $2 a kilogram tax incentive for renewable hydrogen produced from 2027–28.

$7 billion over the medium term for tax incentives in critical mineral production. Firms will be eligible to rebate 10% of refining and processing costs of 31 critical minerals from 2027-28.

$1.5 billion over ten years for solar PV and battery manufacturing. This will fund grants to firms for manufacturing solar PV components at all stages of the supply chain and batteries.

Is this the right thing to do? Economists are usually pessimistic about government efforts to guide industry in this way, pointing to the difficulty of picking winners and the potential for funding to flow in the direction lobbyists want rather than on merit.

Nevertheless, there’s recent evidence industry policy can be effective in spurring long-term structural change to an economy – when done well. After all, targeted assistance and direction by government may have played a role in how East Asian nations such as Japan, Korea and China became manufacturing titans.

But what about the environmental outcomes of these subsidies? Will they turn Australia into a green export giant, shipping green hydrogen instead of LNG and make homegrown solar panels a reality? Will they help drive the green transition?

This is even less clear. Australia’s once-significant manufacturing sector began its sharp decline after we dropped tariffs and opened up to international competition from the 1980s.

Could Labor turn the tide? That will depend on whether the subsidies succeed in creating manufacturing sectors able to compete with international competition. It’s far from guaranteed. But it is possible.

And what about trade-offs between green industry and conservation? In the rush to secure lithium and critical minerals for the green transition, the government has invested $566 million to give mining companies free data and maps. This could do further damage to the environment, if new projects are built on land home to threatened species.

Where’s the “Conserved in Australia” policy?

Nothing is in the budget to tackle our biodiversity and extinction crisis.

This is another missed opportunity. The postponed environment laws aside, the government could have addressed the severe lack of funding for conservation.

What about the goal of protecting 30% of land and seas by 2030? This will take funding to expand protected areas – and to actually conserve species in existing protected areas. Invasive species from deer to blackberries run riot in many national parks.

How much should the government be spending and for what? To give some examples:

– $5 billion would fund the purchase of private land for conservation and long-term management. Australia previously had a fund like this, which is why our protected area estate has grown so much.

– $1.7 billion a year is the expert estimate for how much it would cost to bring all of Australia’s threatened species under active management and recover their numbers.

– $2 billion a year for 30 years would restore 13 million hectares of degraded land, without touching farms or urban areas – about twice the size of Tasmania.

Our natural environment affects our national identity, our mental health, and even our future economic prosperity.

Yes, conservation costs money. But the costs may turn out to be very small relative to the benefits, not only for the diverse species we share Australia with but for its people too. People don’t just need manufacturing jobs – they need nature, too.

Timothy Neal, Senior lecturer in Economics / Institute for Climate Risk and Response, UNSW Sydney

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

Australians have more pet cats than ever before – more than 5 million in total. With the growing number, expectations on pet owners are shifting.

Many cat owners are now voluntarily keeping their cats indoors or in secure runs, and local governments mandate it in some areas. But most pet cats in Australia still roam local streets and gardens.

Broader adoption of keeping cats safe at home would have large benefits for cat welfare, human health, local wildlife and even the economy. So, should pet owners be required to keep their pets contained to their property, as dogs are?

We put that question to thousands of people in a national survey in late 2023, and recently published the results.

We found most people support requiring owners to contain cats. Just one in 12 people (8%) are opposed. The time might be right for nationwide change in how we manage our pet cats.

Local councils are embracing cat containment

From November 1, Geelong City Council will join a fast-growing group of local governments in urban and regional areas that require pet cats to be securely contained 24 hours a day.

More than a third of local councils in Australia now require cats to be contained overnight or 24 hours a day. Most are in the ACT and Victoria.

Given how good cats are at climbing and jumping, containing cats usually requires keeping them indoors or in secure runs.

The main reasons cited by local govenments for these regulations are:

• improving pet welfare: contained cats live longer and healthier lives with fewer vet bills because they are protected from traumatic injuries from car accidents, dog attacks and cat fights, infections, diseases and other misadventures.

• saving wildlife: four out of five cats allowed outside will hunt and kill an average of two to three animals per week. With millions of pet cats in Australia, each year this adds up to 6,000–11,000 animals killed in our suburbs per square kilometre and 323 million native animals killed nationally. Night curfews only protect nocturnal species such as possums.

• reducing nuisance to neighbours: containment results in less disturbance from cat fights and prevents the neighbour’s cat killing the birds and lizards living in your backyard or nearby park, which many community members value.

The public health toll of roaming cats

Another major benefit is less talked about. Stopping pet cats from roaming would greatly reduce rates of cat-borne diseases.

Several diseases which could not exist without cats can be passed to humans. These cost Australia more than $6 billion a year based on costs of medical care, lost income and other related expenses.

The most widespread of these diseases is toxoplasmosis, a parasitic infection that can be passed to humans but must complete its life cycle in cats. Australian studies have reported human infection rates between 22% and 66% of the community.

Cat-borne diseases cause considerable community harm, with an estimated 8,500 hospitalisations and 550 deaths from acute infections and also from increased rates of car accidents, suicides and mental health issues in infected people.

Pet cats are crucial to the rates of these diseases in the community. In suburbs that do not require containment, you’ll find up to 100 roaming pet cats per square kilometre.

Eliminating stray cats from our suburbs is also important to reduce disease rates – just one of the reasons why people should not feed stray cats.

Most of us support containment

A policy requiring all cats to be contained has clear benefits. But would it have support? Rules only produce benefits if people follow them.

This is why colleagues at Monash University and I surveyed more than 3,400 people on whether they would support policies that “require cat owners to keep their cat contained to their property”.

We found a clear majority (66%) of people support cat containment. A strikingly small proportion of people, about one in 12 people (8%), are opposed. The remaining 26% were ambivalent, selecting “neither support nor oppose”.

Other surveys have found almost half (42% or 2.2 million) of Australia’s pet cats are already kept contained by their owners.

Some councils can’t legally require cat containment

Our findings suggest communities would broadly support their local councils if they moved to require cats to be contained.

While councils are responsible for pet issues, state and territory laws greatly influence what councils can and can’t do.

In New South Wales and Western Australia, state laws actually prevent local councils from requiring cat containment (except for in specific circumstances, such as in declared food preparation areas in NSW).

Rules are just the start

To boost compliance, councils need to invest in communicating new rules and the reasons for them. After a grace period, council officers will also need to monitor and enforce the rules.

Communities may need support too, especially if there are costs involved. Councils could, for example, offer rebates for flyscreens to stop cats slipping out of open windows.

Working with other colleagues in 2020, we surveyed Australia’s local governments about their approaches to cat management. Most reported tiny budgets for cat management.

Local governments should not be left to shoulder the cost alone. Federal, state and territory governments are also responsible for Australia’s wildlife (and human health). These governments have a range of projects covering both feral and pet cats.

The Australian government collects A$3 billion a year in GST from spending on pets. Diverting a small proportion into responsible pet ownership programs would make an enormous difference.

Containment has wide backing

Our research shows the community is ready for widespread reform of how we manage all these cats.

Requiring pet cats to be contained is a sound policy choice. But to realise the full benefits, we also need to invest in effective communication for communities, provide rebates to help contain cats, and make sure the rules are followed.

This research was a team effort, involving Kim Borg, Melissa Hatty and Emily Gregg for the national survey, and Sarah Legge, John Woinarski and Tida Nou for the research on cat impacts and management.

Jaana Dielenberg, University Fellow, Charles Darwin University

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

From around 1996 to 2010, Australia was gripped by the millennium drought. As water shortages bit hard, most of Australia’s capital cities built large seawater desalination plants – Sydney, Adelaide, Brisbane, Melbourne and Perth. Remote towns have also built smaller desalination plants.

Most cities didn’t actually use them much. The drought broke in 2010, and desalinated water is expensive. The exception is Perth, which has been hit by declining rainfall, a drying climate and overuse of groundwater. The city will soon open its third desal plant.

As climate change intensifies, other states are also looking to build more desal plants. In South Australia, for instance, there are plans to build one urgently in response to looming water shortages. The Eyre Peninsula, for instance, is expected to run out of drinking water within two years as groundwater runs dry.

But beyond the expense, many of these plants bring environmental problems of their own.

How does desal work?

A desalination plant pipes in seawater, filters out the salt (usually using a process called “reverse osmosis”), and then flushes the salt back out to sea. This creates plumes of hyper-salty brine.

If you position a desal plant near a strong current, this isn’t a big issue – the salt is quickly diluted. But if you pump brine into a gulf or bay without much natural turnover of water, it can lay waste to entire ecosystems. And unfortunately, South Australia has two large gulfs – and two planned desal plants that could kill off giant cuttlefish or decimate mussel farms.

When BHP Billiton was looking to expand its lucrative Olympic Dam uranium and copper mine in the mid-2000s, it had a problem: not enough water. To solve it, the mining giant announced plans to build a desal plant at Point Lowly, in the upper Spencer Gulf.

This was immediately controversial. Point Lowly is very close to the breeding grounds of the famous giant Australian cuttlefish (Sepia apama), a tourist drawcard.

My research suggested the brine outflow from the desal plant would cause environmental harm to these spectacular breeding grounds.

Despite environmental concerns, the Olympic Dam expansion was eventually approved in 2011, and the approval for the Point Lowly desal plant carried forward to the new Northern Water partnership between the state government and the private sector, which involves BHP as a key player.

This, the government states, is designed to:

provide a new, climate independent water source for the Far North, Upper Spencer Gulf and Eastern Eyre Peninsula regions of South Australia, to enable the growth of industries crucial to achieving net-zero goals, including the emerging green energy and hydrogen industries

The government recently changed the preferred location to Cape Hardy, much further down the Spencer Gulf. From as early as 2028, it will produce up to 260 million litres (megalitres) of desalinated water a day for use in mining and green industries.

A separate smaller desal plant (24 megalitres a day) is also planned for Billy Lights Point near Port Lincoln, to provide water for the lower Eyre Peninsula.

If the government was hoping to avoid controversy by moving away from the cuttlefish, it did not succeed. Opposition has come from the local council, First Nations groups, and fishing and aquaculture industries.

The problem with the location at Billy Lights Point is, once again, what happens to the brine. Salty outflows could damage mussel farms, fisheries and ecosystems.

Super-salty brine is pollution

My research suggests these concerns are well founded.

While we might think brine is harmless – it’s salty, like the sea – this is not correct. Desalination produces brine that is twice as salty as seawater. When you pump it back into the sea, it can form a layer of heavier water that creeps along the seafloor as a so-called brine underflow.

Desal brine can be dangerous, especially in waters that don’t mix rapidly. Without sufficient mixing, the oxygen content of the brine underflow falls over time. Eventually, the brine underflow can turn into a dead zone where very little can survive.

Desalination plants also pump out harmful chemicals with the brine, including pre-treatment chemicals, anti-fouling agents, heavy metals, nutrients, organics, chlorine and acids.

This means we should think very carefully about where to build desalination plants. The Spencer Gulf is full of seagrass meadows, the nurseries of the sea, home to leafy seadragons, giant cuttlefish, king prawns and millions of larval and juvenile fish.

The brine can degrade or even destroy marine ecosystems. In the Arabian Gulf, where about half the world’s desal plants are located, researchers have found the pulses of brine “greatly threatens sensitive species”.

Given this marine pollution, any move to discharge desal brine into calm seas that have high ecological significance and do not flush rapidly is extremely risky.

At present, South Australia’s two planned desal projects do not seem to properly value environmental principles.

For instance, while the large Northern Waters project lists Cape Hardy as the preferred site, Point Lowly is still on the list of options. This ignores previous evidence showing the Spencer Gulf flushes slowly, which means a higher risk of environmental damage. And Cape Hardy is still within valuable and vulnerable marine habitats.

The smaller Port Lincoln desalination plant is expected to be operational by 2026 on Billy Lights Point, which borders Proper Bay and Boston Bay in the lower Spencer Gulf.

These bays are ecologically important, as they provide safe havens to marine larvae. They’re also part of the region’s coastal upwelling, a vital source of nutrients for whales and tuna.

The proposed intake and discharge locations of the Port Lincoln plant are within a few kilometres of valuable mussel and tuna farming operations.

Looking forward

While Cape Hardy is environmentally more suitable for desal discharge than Point Lowly, it is still within the sheltered waters of Spencer Gulf. Hence, some environmental degradation is likely to occur here as well.

If authorities are determined to stick with brine-releasing desal, they should urgently look at sites outside Spencer Gulf, such as Ceduna or Elliston. Here, brine would be quickly diluted by the currents.

But there are other options not yet considered.

It is likely we will need more desalination plants as climate change intensifies. The best solution is a desal plant fully powered by renewables – and without brine discharge. How? By cleaning the brine and turning it into a valuable product: salt.

Jochen Kaempf, Associate Professor of Natural Sciences (Oceanography), Flinders University

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

The southern pygmy perch hadn’t been seen in Bendigo Creek since the mid-19th-century goldrush, when a booming town sprang up around the central Victorian waterway. This attractive small fish, which displays bright colours when breeding, is no more than 6–8cm long. Once widespread, the species eventually became locally extinct across the Loddon River catchment, which includes the creek.

But today, thanks to the efforts of community volunteers, scientists and local authorities, there are several thriving local populations of this small fish.

Reintroducing species to their old habitat is complicated. For animal species, we need good information about where to source them from and how many to move. It’s essential to have good habitat ready for the newly restored population.

We should also know how genetically diverse the population is because that can affect its long-term success.

A successful reintroduction depends on researchers, environmental managers and local communities working together. That’s exactly what happened in Bendigo.

Pygmy perch range has shrunk

The southern pygmy perch (Nannoperca australis) was once found in many rivers and streams across New South Wales, Victoria and South Australia. However, the combined pressures of habitat loss and degradation, invasive species such as redfin perch, carp and eastern gambusia, drought and drawing too much water for farming drove many populations to local extinction.

In 2015, recognising the importance of collaboration across management groups and communities, six regional bodies formed the Tri-State Murray NRM Alliance. They developed the “Magnificent Six” project to reintroduce six native freshwater fish species – all small and endangered – in the Murray-Darling Basin, which includes the Loddon River. The southern pygmy perch was first in line.

In 2018, through the tri-state alliance, a partnership between local government, environmental managers, an aquarium business, local community and fish hobbyists was formed. The Molecular Ecology Lab at Flinders University was brought in to provide guidance and genetics expertise. The lab had experience of successful captive breeding and reintroduction of southern pygmy perch in South Australia.

Everyone came together to plan the most effective course of action. We consulted local community members. We discussed where best to collect fish from and to move them. We planned planting efforts to restore suitable habitat.

Building up new populations

In September 2018, local volunteers – guided by environmental managers – collected more than 100 wild fish. These came from three creeks in two nearby river systems: the Campaspe and Avoca Rivers.

They took these fish to the Middle Creek Farm, a private aquarium business in Stratford, Victoria, to set up a captive breeding program. The aim was to make sure we had enough fish to sustain new populations. Over the next year, volunteers helped to breed and raise more than 600 fish for release.

At the same time, volunteers created new homes for these fish in three local wetlands by planting aquatic vegetation and building woody habitat. The combination of woody debris and dense reeds provides refuge from predators like aquatic birds and are particularly important nurseries for juvenile fish.

In January 2020, 800 fish from all three creeks were released across four wetlands, including restored urban wetlands and national parks. The team came back in September that year to monitor how they were doing.

A triumph for community action based on expert advice

Local communities can play an integral role in programs like this. To date, relatively few conservation programs include active public participation. Even fewer consider genetic information.

At every stage of the Bendigo reintroduction, we collected DNA from the fish by taking a small clipping of the tail fin. Our aim was to see how well the program had maintained genetic diversity. This is important for populations to persist in the long term.

We showed the genetic diversity of the parents was maintained. This diversity has helped the new populations to thrive.

Interestingly, we found the different source populations had unique genetic variation and the breeding program had caused some fish to become “mixed” (like hybrids). When we monitored the populations after release, we found more of these mixed fish surviving. That suggests genetic mixing might be important for southern pygmy perch.

This information helped us to make recommendations for future reintroductions elsewhere.

Everyone benefits

The program was a huge success. All three populations are thriving – so much so that 2,800 fish were taken from our release sites to start a new population in another site within the Gunbower Forest along the Murray River last September. The species was last recorded there in 1997.

With their voracious appetite for mosquito larvae, these populations of pygmy perch may offer a natural solution for pest management. They are also a key food source for many native freshwater fish and waterbird species.

The community benefited too. Seven new landcare groups and more than 20 landholders are now part of reintroduction programs for other fish species. Volunteer organisations increased their social media and public footprint. Pygmy perch have also become popular fish in dams and backyard ponds.

Aquariums of southern pygmy perch are being used in high schools to teach students about fish conservation, pest management and water chemistry.

How can you get involved?

Communities are working tirelessly to restore lost biodiversity across Australia. To help bring back a lost local species you can:

• get involved with your local community “Friends of” conservation groups as well as regional groups, which are great for driving change in your area

• approach local councils and government to provide support and contact relevant stakeholders

• call in university researchers, of course. Many of us would love to provide our expertise and skills to conservation efforts.

Together, we can improve the conservation status of threatened species and restore our declining biodiversity.

Sean Buckley, Lecturer in Molecular Ecology and Environmental Management, Edith Cowan University and Luciano Beheregaray, Matthew Flinders Professor of Biodiversity Genomics, Flinders University

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

For years, the electricity sector has been the poster child for emissions cuts in Australia. The sector achieved a stunning 26% drop in emissions over the past 15 years, while other sectors have hardly budged. The share of renewable energy has gone from 7.5% to more than 30% in that time.

But unfortunately, this impressive pace is not fast enough.

Investments in renewable energy plants slowed in 2023 – financial approvals for new solar farms shrank more than a third and no new wind farms won backing. By the end of that year, Australia had 56 renewable energy projects under construction, down from 72 a year earlier.

For Australia to achieve the federal government’s 43% emissions cut target by 2030, and the deeper and swifter cuts required after that, we need to accelerate. The federal government wants the electricity sector to be generating at least 82% from renewable sources by 2030. The electricity sector needs to be clean enough by that year to make electrification the better choice for sectors heavily dependent on fossil fuels, from transport to heavy industry to household gas.

And it won’t end there. After 2030, when other sectors start to electrify en masse, the electricity sector will need to keep building more and more new renewable capacity to keep up.

If it doesn’t, it simply won’t be possible to eliminate the remaining 56% of our emissions that come from producing and burning fossil fuels. And that’s before Australia even starts looking at expanding its industrial base to become a so-called “renewable superpower”.

There are three reasons the electricity sector isn’t achieving the required pace at the moment.

Not enough poles and wires

New wind and solar farms need new transmission lines to get their electricity to users. That’s because the good sources of wind and sunshine aren’t in the same places as the existing transmission network. And even if they were, we’d still need to upgrade and build transmission because of the growth in demand.

The Australian Energy Market Operator estimates 50% of the transmission needed to deliver a clean, reliable, affordable energy supply in 2050 needs to be constructed in the next six years.

But most of these transmission lines are yet to be built.

Instead, renewable generators have had to connect to existing lines, which have become congested. So even when new renewable installations get approvals for construction, their output can be curtailed because they can’t get it to consumers. This has hit developer finances hard.

And many rural communities aren’t happy with the new transmission lines planned for their regions. While many of the required lines have been known about in the energy sector for years, the communities that will host them are only finding out about them now. Understandably, many object.

As well, bottlenecks in the planning approval bureaucracy mean things are slow to get built. This isn’t just about transmission lines: it also applies to new renewable generators and even upgrading roads so equipment and machinery can be used safely.

Coal hanging on

There’s still uncertainty about when coal generators will leave the market.

We need to build replacement capacity for ageing coal generators before they retire but no one wants to build new generators to replace the coal if they aren’t sure when demand for their electricity will emerge.

Generators are required to declare their earliest exit date if that date is less than three-and-a-half years away, but there’s nothing to stop them pushing that date out. That’s what Delta Electricity did last year, when it changed the closure date for the Vales Point power station in New South Wales from 2029 to 2033.

On top of this, nervous state governments have started making opaque deals to pay coal power stations to stay open, as insurance against the slow pace of the renewables build.

Governments aren’t coordinating well

Every state government on the east coast has a renewable energy target. So does the federal government. But these targets were set as arbitrary percentages linked to arbitrary dates, not chosen to deliver the cleanest, most reliable, cheapest energy system for consumers.

State and federal governments choose their targets in isolation, which drives up overall costs. To give just one example: both New South Wales and Queensland have established “renewable energy zones” in New England shire, located right across the border from each other. Developing these areas as a single zone should cost less overall, but no such interstate efficiency has emerged. Each state has gone its own way.

Is there a way out?

All of the above has led to a policy quagmire that has bogged down Australia’s energy transition.

In our report released last month, my colleagues and I argue the best way forward is to temporarily put aside a desire for neat, market-driven policies. Instead, we think governments and industry need to accept an approach that could feel ad hoc or disorganised at times in the next decade while coal exits are taking place.

During this time, governments will probably need to intervene regularly to coordinate new transmission, new generation, and coal exits, so the lights stay on.

Once coal is a no longer a substantial part of the market, it will be time for governments to step back. Beyond 2030, electricity demand is expected to keep growing, and the renewables building task will continue.

Governments need to start designing the rules that will govern this new electricity system. It requires asking a fundamental question: what will the respective roles, rights, and responsibilities of energy consumers, industry, and governments be in the future?

Keeping the system reliable will be a fundamentally different task when the amount of electricity generated depends on the weather. Market rules must change to ensure there is always sufficient generation available to meet demand in this new electricity system.

And carbon pricing – a political taboo for so long – will need to be discussed again. Even when the coal generators have closed, a vital share of our electricity will come from gas. The electricity sector needs a clear and enduring carbon price for the energy sector to guide gas-plant entries and exits, and ensure they pay for their emissions.

Governments will need to better integrate and orchestrate all forms of distributed energy resources, from rooftop solar panels to electric vehicles, particularly as electric vehicles become able to use their batteries to help power the grid.

Australia may be able to muddle through the next few years, but voters will not forgive their political leaders if they mess up the post-coal era and fail to deliver the trifecta of clean, affordable, and reliable energy. The hard work starts now.

Alison Reeve, Deputy Program Director, Energy and Climate Change, Grattan Institute

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

Australia’s unprecedented Black Summer bushfires in 2019–20 created ideal conditions for misinformation to spread, from the insidious to the absurd.

It was within this context that a bizarre story went viral on social media.

This was a tale of heroic wombats herding other animals into their fireproof burrows to save them from the flames. At the time, we explained this story was largely inaccurate. But now we’ve investigated in more detail, and confirmed it may contain a kernel of truth.

The burrows of common wombats are deep and complex. They can be over 15 metres long with multiple entrances and chambers. So, even if wombats don’t shepherd wildlife into their homes, their burrows might act as “fire refuges” – providing vital shelter, food, and even drinking water during and after a bushfire.

Wombat burrows are not just for wombats

We set up 56 cameras in forests north of Albury, New South Wales, which burned during the Black Summer bushfires. Some areas suffered more than others, so we were careful to select sites that varied in how severely they burned.

Half of the cameras were pointed at wombat burrows and the other half were set up nearby – in areas with the same types of plants, but no burrows. Then we monitored the burrows from June 2021 to April 2022 to see which animals used them, and how.

We found 56 animal species at wombat burrow sites (19 mammal species, 33 bird and four reptile).

Native species such as bush rats, agile antechinus, lace monitors and birds such as the painted button-quail, were more abundant in and around burrows than nearby control sites. Even a threatened species, the heath monitor, was seen emerging from a burrow.

Wombat expert Barbara Triggs, who literally wrote the book on wombats, had seen several of these species “scurrying away from burrow entrances” and emerging “from small crevices in the the walls” of wombat burrows. So our results are supported by her, and others’, observations.

Overall, burrows were hotspots of mammal activity, with more mammal species recorded at burrows than control sites. These tended to be smaller mammals, presumably because they can use the burrows without bothering the wombats.

Bigger animals such as kangaroos and wallabies tended to avoid the burrows. They may have been wary of a encountering a cantankerous wombat. Wombats are known to defend their territories.

We observed some fascinating behaviour at wombat burrows. In total, 31 species were found interacting with the burrows. This included 30 species inspecting the entrance, 11 foraging (feeding in or directly around the lip of the burrow), and ten entering or emerging from burrows.

We also saw animals drinking and even bathing in pools at burrow entrances that temporarily filled with water after rain.

While water was not scarce during our study period, this suggests wombat burrows are providing a valuable ecosystem function that might help other wildlife. It’s an interesting observation that warrants further investigation.

Burrow use by several native wildlife species was highest in areas that burned most severely. This supports the idea that wombat burrows act as a kind of refuge for native wildlife after fire.

Underground networks

Our results are just the tip of the iceberg. Globally, many burrowing species provide habitat for others. From the American badger to the giant armadillo, burrows provide shelter and resources for species across many ecosystems.

Closer to home, sand goanna burrows provide shelter for at least 28 animal species. And bilby burrows have been described as an “outback oasis” for their role in supporting birds, reptiles and mammals.

We’re not the first to find animal burrows offer refuge after fire. A US study published in 2018 found gopher tortoise burrows in burned areas had 8.5 times more wildlife species than burrows in nearby unburned areas.

Help wombats help others

The star of our research is the bare-nosed wombat. While not listed as threatened with extinction, their numbers have declined markedly since European colonisation.

Our research adds to a growing body of evidence that suggests protecting wombats will benefit various species across many Australian ecosystems.

As large and severe fires become more common in forests across southeastern Australia, our wildlife will need all the help they can get – including the humble wombat burrow.

Grant Linley, PhD Candidate in Ecology, Charles Sturt University and Dale Nimmo, Professor in Ecology, Charles Sturt University

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

The Southern Ocean, a region critical to Earth’s climate, hosts vast blooms of microscopic ocean plants known as phytoplankton. They form the very basis of the Antarctic food web.

Using a fleet of robotic floats, our study published in Nature today reveals that windblown dust delivers enough iron to support a third of the Southern Ocean’s phytoplankton growth. Knowing this will help us understand how global warming will affect key climate processes phytoplankton are involved in.

The Southern Ocean acts as a climate “shock absorber”. Its cold waters and vast area capture up to 40% of human-generated carbon dioxide (CO₂) absorbed by the planet’s oceans each year.

Human-generated CO₂ mainly enters the ocean as it dissolves at the surface. However, biological processes that transfer vast quantities of CO₂ from the surface to the deep ocean play a critical role in the ocean’s natural carbon cycle.

Even slight changes to these processes in the Southern Ocean could weaken or strengthen the climate shock absorber. This is where phytoplankton play a key role.

Phytoplankton: tiny but mighty

Like plants on land, phytoplankton convert CO₂ into biomass through photosynthesis. When phytoplankton die, they sink into the deep ocean. This effectively locks away the carbon for decades, or even hundreds of years. This is known as the biological carbon pump, and it helps to regulate Earth’s climate.

Phytoplankton need nutrients and light to flourish. Nitrogen, in the form of nitrate, is one of these essential nutrients and is plentiful in the Southern Ocean. During the bloom period in spring and summer, phytoplankton consume nitrate.

This offers scientists a unique opportunity – by measuring how much nitrate disappears seasonally, they can calculate the growth of phytoplankton and the carbon sequestered in their biomass.

But there’s a twist. Iron, another essential nutrient, is in short supply in the Southern Ocean. This shortage stunts phytoplankton growth, lowering the efficiency of the biological carbon pump.

Dust boosts life in the Southern Ocean

Iron is commonly found in soil. Winds carry iron-rich dust from the continents to the oceans. This supply of dust-derived iron can trigger phytoplankton blooms, greening stretches of the ocean and strengthening the carbon pump.

Historically, to study the effects of iron fertilisation on phytoplankton – whether the iron came from dust, other natural sources, or was deliberately added – scientists had to embark on expensive research voyages to the remote Southern Ocean.

However, insights from such experiments were restricted to small regions and short periods during certain seasons. Little was known about the impact of dust on phytoplankton all year round across the whole of the Southern Ocean.

To address this gap, we turned to robots.

Ocean robots follow the trail of dust

Over the past decade, research organisations have deployed a fleet of robotic ocean floats worldwide. These robots tirelessly track ocean properties, including the nitrate concentration.

In our study, we analysed nitrate measurements at 13,600 locations in the Southern Ocean. We calculated phytoplankton growth from nitrate disappearance and combined these growth estimates with computer models of dust deposition.

With this new approach, we uncovered a direct link between the supply of dust-derived iron and phytoplankton growth. Importantly, we also found the dust doesn’t just coincide with phytoplankton growth – it actually fuels it by supplying iron.

We used this relationship to build productivity maps of the Southern Ocean — past, present or future. These maps suggest that dust supports roughly a third of the phytoplankton growth in the Southern Ocean today.

During ice ages, a combination of drier conditions, lower sea levels and stronger winds meant dust deposition on the Southern Ocean was up to 40 times greater than today.

When we apply dust simulations of the last ice age to our newfound relationship, we estimate that phytoplankton growth was two times higher during these dustier times than it is today.

So, by fuelling phytoplankton growth, dust likely played an important role in keeping atmospheric CO₂ concentrations low during ice ages.

Why does it matter?

Global warming and land use changes could rapidly change dust delivery to the ocean in the future.

These shifts would have important consequences for ocean ecosystems and fisheries, and our research provides the tools to help forecast these changes.

To keep global warming below 1.5˚C, it is imperative that we find safe and effective methods for actively removing CO₂ from the atmosphere. One proposed and controversial strategy involves fertilising the Southern Ocean with iron, mimicking the natural processes that decreased CO₂ during ice ages.

Our results suggest such a strategy could boost productivity in the least dusty parts of the Southern Ocean, but uncertainties remain around the ecological consequences of this intervention and its long term effectiveness in capturing carbon.

By studying how nature has done this in the past, we can learn more about the possible outcomes and practicality of fertilising the ocean to mitigate climate change.

Jakob Weis, Postdoctoral research associate, University of Tasmania; Andrew Bowie, Senior Research Scientist in Marine Biogeochemistry, University of Tasmania; Christina Schallenberg, Research Scientist, CSIRO; Peter Strutton, Professor, Institute for Marine and Antarctic Studies, University of Tasmania, and Zanna Chase, Professor, University of Tasmania

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

The past decade has seen an explosion of new research into some of the most fascinating sounds in the sea: the vocalisations of whales and dolphins.

Scientists have uncovered how humpback whales learn songs from neighbouring populations, so that these songs travel from western Australia to South America. They discovered bowhead whales singing 184 different songs over three years, and learned how bottlenose dolphins use signature whistles to shore up alliances.

Researchers have also showed that sperm whale vocal dialects are more different the more they are in contact with each other across the entire Pacific, suggesting these dialects function as ethnic markers. Advancing technology in the form of drones, acoustic tags and recorders mean such insights are accumulating rapidly.

Much of what whales and dolphins signal seems to relate to identity within social contexts. This can include identifying alliance members, or members of long-term social units and clans, or a particular population or species. Vocal communication also builds and reinforces social bonds and coordinates cooperative foraging.

We have also seen the resurrection of an old idea: that hiding behind all these findings is really a human-like language. If we can just find the right tools, the thinking goes, we can decode it and start talking to whales like we talk to our neighbours.

The hottest new tool is AI. Reading some of the press around the topic, you could be forgiven for thinking such conversations are imminent.

Two recent studies stand out for the dramatic claims they make about whale language. One details a humpback responding to the playback of a call with a similar one (but then ultimately losing interest).

This study’s importance was to demonstrate that such playback studies are possible, because playing back an animal’s calls and observing their reaction is a tested method for uncovering the meanings and functions of signals.

It’s not, however, the first playback to whales or dolphins, and neither, as the scientists claimed, were they “conversing” with the whale. If this was a “conversation”, then we’ve been having more insightful “conversations” with other species for decades – there have been over 600 such playback studies on birds.

The second study is a detailed analysis of patterns of clicks, called codas, produced by sperm whales. It shows that the whales appear to synchronously change the tempo of their codas when using them in exchanges with each other.

Such synchronous chorusing is not unique to whales. It happens across the animal kingdom, from fireflies to primates. Few animal displays are as breathtakingly synchronised as the four-part chorusing of plain-tailed wrens, while happy wrens use pair-specific duets to signal commitment to mates.

Nonetheless, the sperm whale findings are exciting, and fit in with our general understanding of codas having a social bonding function. But the scientists also tried to force these tempo changes into a “phonetic alphabet”, “like the International Phonetic Alphabet for human languages”, and it is this latter claim that has grabbed headlines.

There is, however, no evidence that sperm whales use these different tempos in anything like the complex sequences that characterise human language. We find better evidence for complex sequencing rules in Bengal finches. I wonder why we don’t see headlines about phonetic alphabets or imminent conversations with these birds?

Don’t believe the hype

We’ve been closely studying cetacean vocal behaviour in the wild and in captivity for several decades now. Compare that to how quickly you or I can start exchanging ideas with another person we don’t share a language with – because we use our theory of mind to understand each other as communicative agents.

If language was there, I think we would have found it by now. The most powerful language detector we know of sits between our ears, and we used it to effortlessly learn the language of our childhood as toddlers. As the story of Helen Keller shows, language finds a way.

Persuading the BBC not to describe sperm whale clicks as “language” in their Blue Planet II series was the highlight of my science communication career. Why?

A lot of complex communication is going on in cetaceans, much of which we still don’t understand. However, I am convinced that we should drop the stifling and anthropocentric focus on language. It crowds out other perspectives on what is going on – for example, the relationship between rhythm-based communication and music might be a better way to understand the bonding function of coda synchrony in sperm whales.

We should be wary of ranking species on a single dimension relative to humans, as if all evolution is a path to something like us (much like early anthropologists ranked societies by their progress toward western “perfection”). Instead, let’s take ourselves off the top of the ladder and see other animals as distinct branches of an evolutionary tree.

Both of the research groups promoting talking to whales are linked to, or name themselves after, the Search for Extra-Terrestrial Intelligence (Seti). The leaders of one group, Project Ceti, argue that understanding whale “language” will help us when we meet ET.

We’ve been here before. John Lilly also leaned into Seti, promoting the idea that dolphins were an alien intelligence with a complex language. His weak evidence ultimately evaporated in a cloud of hype and hallucinogens.

Unfortunately, his claims kept the important discovery of bottlenose dolphin signature whistles in the shadows for far too long, and cast a cloud of disrepute over the entire field of cetacean communication that took decades to disperse. It would be tragic if today’s important insights suffered the same fate because of irresponsible claims and a narrow focus on language.

We should strive to understand and value these awesome creatures for what they are, not for how they might sooth our cosmic loneliness.

Luke Rendell, Reader in Biology, University of St Andrews

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

Swimming through the crystal clear waters of the Maldives, a nation renowned for its marine life, it could be easy to forget that these delicate ecosystems stand on the frontline of climate change and that seagrass habitats are in crisis globally.

Now, my research, which combined hundreds of hours of fieldwork with thousands of satellite images, has uncovered something unexpected: Maldivian seagrasses have expanded three-fold over the last two decades – and island populations could be playing a part.

I also discovered that seagrass is surprisingly three times more likely to be found next to inhabited islands, rather than uninhabited. So this flowering plant seems to benefit from living in seas close to humans.

Seagrasses grow along coasts all around the world. They can help guard against climate change yet they are frequently underappreciated. In the Maldives, seagrass meadows are dug up to maintain the iconic white beaches that are a frequent feature of honeymoon photos.

Important marine habitats have declined in the Maldives. Amid this backdrop of environmental uncertainty, I have spent more than three years studying seagrasses here alongside a team of scientists. We found that seagrasses are faring remarkably well and one of the most plausible drivers could be the supply of nutrients from densely populated areas, such as tourist resorts.

Every day, human activities could provide valuable nutrients for seagrass habitats in an otherwise nutrient limited environment. Food waste is traditionally discarded into the sea from the beach and rain can wash excess fertilisers from farmland into the ocean. As human populations and fertiliser use have both increased, we suspect that seagrass meadows have started to thrive and expand as a result of this increased nutrient supply.

Additionally, building work around islands may create more suitable habitats for seagrass. Land reclamation is widespread across the country as the population has expanded by 474% since 1960.

During this development, sand is dug up from the seabed and some inevitably spills into the water. The structure of seagrass meadows can slow down local water currents, promoting suspended sand grains to sink and creating more sediment for future generations of seagrass to grow into.

Currently, nutrient inputs seem to be creating just the right conditions for seagrasses. But if nutrients continue to increase, there is a risk that the seagrasses will be outcompeted by seaweeds and smothered. Continued land reclamation works that disregard seagrass may also remove this important habitat. So the future of this Maldivian success story may therefore largely lie in our hands.

The ecotourism paradox

Although seagrass removal has done little to curb habitat expansion, it highlights a troubled relationship with the tourism industry upon which so many jobs in the Maldives depend. Because it can ultimately make water depths shallower, seagrass can limit boat access and mooring, and therefore interfere with daily life. The proliferation of seagrass in areas of domestic refuse has understandably damaged its image in the eyes of the public.

But, by making coastal waters shallower, seagrasses reinforce coastal protection. And by growing close to refuse sites, they absorb excess nutrients and clean the water of pathogens. Despite being a vital tool in the fight against climate change, seagrass clearly has an image problem on the islands.

As a marine ecologist, I firmly believe that conservation scientists - and ecotourists - have an important role to play in conveying the value of seagrasses. Conservationists must also fully appreciate the challenges that meadow expansion can bring to local communities, and understand how the needs of conservation and tourism may differ.

There is hope. A campaign called #ProtectMaldivesSeagrass, recently launched by Blue Marine Foundation and Maldives Underwater Initiative, led to 37 resorts (out of a total of 168) pledging to protect their seagrass meadows. Additionally, the data from my research can be used to protect seagrass habitats and quantify their value to people and nature.

Hopefully, the unexpected – yet welcome – success of seagrass in the Maldives is a cause for conservation optimism. And perhaps tourist resorts can learn to love their newly expanding neighbours.

Matthew Floyd, PhD Candidate, Marine Ecology, Northumbria University, Newcastle

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

A mighty river is flowing out of the Amazon rainforest, and it’s not the one you’re thinking of. In the first kilometre above the forest canopy, a “flying river” is transporting moisture evaporated from Amazonian trees southwards along the Andes mountains towards Rio Grande do Sul, the southernmost state in Brazil.

Almost the entire state – an area larger than the UK – is currently affected by unprecedented floods. The flying river has acted like a firehose, fuelling five months of rainfall in just two weeks, further enhanced by a strong jetstream located in just the wrong position above the region. And, based on future projections of climate change, this situation will likely get worse as the temperature rises.

Since the beginning of May, those massive floods in Rio Grande do Sul have made world headlines. In the state’s capital, Porto Alegre, the Guaíba river is more than five metres above its normal level, breaking a record set in 1941. The death toll is 149 and growing, with 108 still missing. The floods have displaced more than 600,000 people and directly or indirectly affected more than 2 million, in 446 of the 497 municipalities in the state.

In various municipalities, the water and energy systems collapsed, leaving hundreds of thousands of homes with no power or drinking water. Schools suspended classes and the state’s main roads and airport are closed.

While the southern part of the country is under water, a heatwave caused record-breaking temperatures in the states of São Paulo, Rio de Janeiro and Minas Gerais. For scale, this is similar to all of northern France being flooded while Barcelona swelters in 40°C heat.

This is not the first time the southernmost part of Brazil has been affected by such large-scale disasters. Similar weather systems, featuring moisture from the Amazon near the surface and the jetstream crossing the Andes high above, were associated with floods between September and November 2023, as well as major floods in 1997 and 1983.

A combination of factors makes these floods more likely. For instance, warm ocean temperatures in the tropical Pacific (still currently the case, even as El Niño starts to decay) is associated with these weather systems, as are abnormally warm tropical Atlantic temperatures, which add more moisture to the air brought south in the flying river.

Things to come

Is this event a sign of things to come for southern Brazil? As the atmosphere warms, it can carry more water, which means there is the potential to form massive clouds and heavy rains. This is a bit like buying a more absorbent sponge: it can hold more water but when you squeeze, more water falls out.

In fact, we are already observing this. Compared with the floods in 1941, this time the excessive rainfall was concentrated in a much shorter period, meaning the water rose much faster. Future climate projections already indicate that a warmer atmosphere results in an intensification of the flying rivers from the Amazon into south Brazil and adjacent regions, and more precipitation.

We have analysed results from state-of-the-art climate models that are able to simulate storms across South America in detail, just a few kilometres across. These indicate that extreme rainfall like that happening now is likely to become more frequent in the future, and such risks may in fact be underestimated by the previous generation of climate models.

These simulations, run under UK-Brazil and South America-US partnerships, are being used to assess such risks in southern Brazil and right across South America. Early results suggest that, as in Africa, parts of Europe, North America, India and elsewhere, short but very intense rainfall is likely to happen more often as the planet warms, irrespective of the unique weather systems that may affect particular regions.

Marcia Zilli, Postdoctoral Researcher in Climate Dynamics, University of Oxford; Caio Coelho, Senior Research Scientist, Center for Weather Forecast and Climatic Studies (CPTEC), National Institute for Space Research (INPE), Instituto Nacional de Pesquisas Espaciais (Inpe), and Neil Hart, UKRI Future Leaders Fellow, University of Oxford

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

Thirty years ago, while counting barnacles, limpets and seaweeds along rocky shores, I started noticing a daily tide of litter, mostly plastic. As a marine biology PhD student at Liverpool University, I kept removing it, but the next day, there’d be more.

I’m now a leading international expert on microplastics, a term I coined on May 7 2004 to describe fragments of plastic measuring as small as a millionth of a metre. As I work to help reduce the grip of plastic pollution on our planet, the solutions are clear to me.

Regulators, governments and citizens all urgently need to turn off the tide of plastic pollution at its source by reducing the production of plastics. But having just returned from the UN global plastics treaty negotiations in Ottawa, Canada, it’s frustrating to see the lack of consensus among nations about how to address this global problem.

Disturbed by the scale of the plastic contamination I first noticed on that beach in 1993, I felt compelled to act. I recruited students and the local community to help with the annual Marine Conservation Society’s beach clean. We recorded what we found on printed templates.

Back then, a new tool was just becoming available for data compilation: the Excel spreadsheet. The budding scientist within drove me to tabulate what we removed, based on the categories on the printed templates that included bottles, bags, rope and netting. Suddenly, it struck me that the most numerous items had no category. Fragments of larger plastic items, which appeared by far the most numerous were not being recorded. I got curious and wondered what the smallest plastic pieces on the shore were.

When I began teaching a few years later, I challenged my students to find the smallest pieces of plastic on the beach. Looking amongst the sand grains, there they were – tiny blue and red fibres and fragments.

An almost forensic journey ensued to confirm their identity. In collaboration with a polymer chemist, we confirmed the tiny fragments were common plastic polymers – polyethylene, polypropylene, polyvinyl chloride (PVC) – that presumably formed via mechanical degradation and were accumulating as fragments smaller than the grains of sand themselves.

I was hooked on discovering more about this new form of contamination. Working initially with postgraduate students at the University of Plymouth where I was lecturing, we found that these pieces were common on the shore and in seabed mud and we showed they were eaten by marine life. Most alarmingly, we used archived samples of plankton that had been collected decades previously to demonstrate that the abundance of microplastics had increased significantly since the 1960s and 1970s.

I pulled together nearly a decade of this research into a one-page summary entitled “Lost at sea: where is all the plastic?” That paper, published in the journal Science 20 years ago, was the first to use the term microplastics in this context. Within a couple of weeks, this became a worldwide news story.

Everyone wanted to know whether microplastics were harmful. I set out to establish the wider distribution and determine whether they might be harmful to humans and wildlife.

Despite huge media and policy interest, funding was a challenge. One anonymous reviewer commented that there will never be enough plastic in the oceans to cause the sort of harm Thompson wants to investigate.

Over the years that followed, my team and I showed that microplastics were common on shorelines worldwide, they were abundant in the deep sea, in Arctic sea ice and in multiple species of fish. They weren’t just polluting marine environments. They were present in rivers and snow from near the summit of Mount Everest. Everywhere we looked, we found evidence of microplastics.

By 2008, the term microplastic was highlighted by the EU’s flagship marine strategy framework directive, a policy introduced to maintain clean, healthy, productive and resilient marine ecosystems. It stipulated that “the quantities of plastic and microplastic should not cause harm in the marine environment”.

We demonstrated that, if ingested, microplastics could transfer from the gut to the circulatory system of mussels and that nanoparticles could pass through the bodies of scallops within a matter of hours. We demonstrated the potential for chemical transfer to wildlife and confirmed that the presence of microplastics could have negative consequences, reducing the ability of organisms to put on weight.

A UK parliamentary environmental audit committee requested a special report on microplastics in 2016. I was called to give evidence, and perhaps prompted by comments from my colleagues, MP Mary Creagh referred to me as the “godfather of microplastics” and so it entered the public record.

There are now thousands of studies on microplastics published by researchers worldwide. Policy interventions resulting from this work include the UK ban on plastic microbeads in rinse-off cosmetics, and EU legislation to prohibit intentional addition of microplastics to products which could prevent hundreds of thousands of tonnes of microplastics entering the environment.

However, the largest source of microplastics is the fragmentation of larger items in the environment. So ultimately, we need to take action to reduce the production of a wider range of plastic products than just those containing microplastics.

Without action, plastic production could triple by 2060. Yet, some nations seem set on a path to increase production rather than reduce it.

Treaty negotiations

Last week, I was in Ottawa where 180 nations debated the content of the global plastic pollution treaty, a text that contains more than 60 references to microplastics.

What can be done to halt this accumulation? Microplastics are almost impossible to remove. Even for larger items, clean up won’t solve the problem. Novel materials such as biodegradable plastics may offer benefits in specific circumstances but won’t solve plastic pollution.

I left the negotiations with mixed emotions. Pleased that the scientific community had delivered sufficient hard evidence – including some of my own research – on plastic pollution to initiate the need for this global treaty. Saddened that 180 nations found it so hard to reach a consensus on the way forward. Negotiations failed to stipulate that independent scientists should even be included in formal expert working groups.

Like many scientists who helped deliver the evidence of harm, it’s immensely frustrating to potentially be sidelined from an international process that hopes to deliver solutions. It may be hard for some to swallow – I saw one delegate holding a single-use plastic water bottle behind his back during negotiations. Contrary to the outcome of those midnight discussions in Ottawa, the focus must be on prevention by reducing global production of plastic polymers and ensuring any plastic items we do produce are essential, safe and sustainable.

Richard Thompson, Professor of Marine Biology, University of Plymouth

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

Every spring, hundreds of thousands of birds leave their winter habitat on Poyang, the largest freshwater lake in China, and fly north over the most densely populated region on Earth to reach their breeding grounds in Siberia. As with any long-distance journey you might take, these birds need to make stops where they can find a good meal and a chance to refuel.

Migratory birds must make use of food that is only available seasonally. Grass-eating birds like geese follow fresh, green shoots that appear as the season unfolds and the geese move northwards. The brief window when this young, spring grass is at its most nutritious and abundant can last as little as three weeks.

Such a fine-tuned strategy can become a liability. Geese can only eat when they arrive in the right place at the right time, but climate change has disrupted when and how long this seasonal food source is available. Migratory birds may arrive too late in one area if rising temperatures have ushered spring in earlier, for example. If birds cannot replenish their energy stores during migration they risk their ability to breed successfully when they reach their destination – and could even starve.

Along with colleagues, I have investigated the impact of climate change on 16 migratory waterfowl in Asia over the past 21 years. We compared how well a series of stopover sites on their migration route would fare as food sources as the climate changes and found that it is challenging for birds to solely rely on eating enough tasty grass to make the journey safely.

Fortunately, in other research which involved attaching satellite tracking devices to migratory geese and swans, we discovered other food sources on their route from Lake Poyang to Siberia.

Leftover seeds can help birds breed

I tagged 246 birds in total: 102 greater white-fronted geese, 74 tundra bean geese, 58 swan geese (an endangered species) and ten tundra swans which stopped over in the Northeast China plain before heading to their breeding grounds in Siberia.

Do the seasons feel increasingly weird to you? You’re not alone. Climate change is distorting nature’s calendar, causing plants to flower early and animals to emerge at the wrong time.

This article is part of a series, Wild Seasons, on how the seasons are changing – and what they may eventually look like.

Some birds can stay over a month in this region. Vast wetlands were once common here, offering important foraging and roosting areas for east Asian waterbirds preparing for the next leg of their journey to the high Arctic. Most have since been converted to cropland growing soybeans, corn, and rice.

The loss of wetlands as farmland has expanded and is a worrying trend globally. It has forced waterbirds to turn from natural vegetation to agricultural land as a source of food.

In the Northeast China Plain, migrating birds eat seeds left over after harvesting. As soon as the snow melts, these seeds are ready for hungry beaks to dig out. Leftover seeds mean that birds which do arrive before spring has started can still find sufficient food.

What’s good for the goose…

In fact, we found that birds tend to forage on seeds first and then shift their diets to spring vegetation as it emerges, taking advantage of both wetland and farmland habitats. Farmland seeds will become more and more important as natural habitats decline.

Mechanised harvests, which tend to leave more seeds in the field, could provide more food for birds. But protecting wetlands from destruction is still critical, and that will require limiting how much farmland is reclaimed and the intensity of cattle grazing. Lowering these forms of disturbance and encouraging bird-friendly tourism would help swans and geese use both types of habitat during their stopover.

If healthy wetlands accompany farmland, birds can eat natural vegetation when farmers sow their crops and so minimise their impact on crop yields. Seeing birds as part of the landscape, and not as intruders on farmland, can help preserve this biodiversity on the wing.

Yali Si, Assistant Professor of Ecology, Leiden University

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

The weather is warmer and the nights are lighter. What are those black, curved silhouettes looping in the sky?

Assuming you are looking at birds and not attending the World Boomerang Championships, those shapes will likely be the UK’s only breeding member of the Apodiformes (a grouping that includes the hummingbirds): the common swift (Apus apus), harbinger of summer.

People in the UK tend to think of these birds as theirs, but really, they are tropical African species that spend a few months of the year at temperate latitudes. Competition for food, shelter and mates is intense in the tropics, so swifts evolved migration to take advantage of the seasonal boom in plant growth at temperate latitudes. Their breeding range stretches from Ireland to China and birds from the eastern edge of their range make epic annual round trips of 30,000km.

For swifts, migration to temperate latitudes should mean access to lots of flying insects to feed their young and much less competition from other species to eat them. Like other aerial insect feeders, swifts can’t stay through the winter as there is nothing to eat and so nothing to keep them here.

Do the seasons feel increasingly weird to you? You’re not alone. Climate change is distorting nature’s calendar, causing plants to flower early and animals to emerge at the wrong time.

This article is part of a series, Wild Seasons, on how the seasons are changing – and what they may eventually look like.

These birds are much-loved symbols of the changing seasons. So how are they faring as rising temperatures change when seasons arrive and what form they take?

Swifts getting swifter

Swifts are arriving on average about five days earlier in the UK than they were in the 1960s, but they are also leaving significantly earlier too – the only common migrant bird to do so in the UK. Many other species are deciding to extend their summer residency and have multiple broods.

There is still variation between years, but the swifts were very late this year. In this wet, cold spring, I saw my first here in the Longdendale Valley of Derbyshire in England on May 3; by way of comparison, in the unseasonably sunny weather of spring 2020, I saw my first Longdendale swift as early as April 19.

Cold and wet weather is bad for anything that eats flying insects, which aren’t active in these conditions and are more difficult to catch even if they were. One way swifts can weather these challenges is by going on very long foraging trips far from their nest sites to avoid storms. Adults and nestlings can also lower their metabolic rate while sitting on the nest (a phenomenon called torpor) to save energy.

Swifts struggle with prolonged wet periods. A recent study linked an increase in rainfall in June and July from 1975 to 2015 with higher nest failure rates, smaller broods and lower survival of swifts in their first year of life, as they can’t find enough food to feed themselves or their chicks. This is likely to be compounded by potential declines in their invertebrate prey, which are very sensitive to weather conditions like temperature and rainfall.

Cold, inclement springs like this year’s may also kill large numbers of swifts as they migrate through the Mediterranean by preventing them refuelling, leading to starvation, although there have also been instances of heatwaves killing large numbers of swifts as they overheat in their nests in roof cavities in the same region, something which might become a problem in the UK in future.

The cues of birds to migrate come both from an internal clock and factors in their environment, like changes in the seasons. Evidence suggests that species which are not adjusting their migratory schedules in the face of global change are more likely to be in decline and swifts do not appear to be as flexible as some other species in arriving earlier.

Tailored swift bricks

Longer-distance migrants are then more likely to be declining than shorter ones, but scientists’ understanding of the role of climate change in driving declines is still limited and complicated by so many other facets of global change.

Beyond reducing the carbon emissions and habitat destruction associated with our diets and lifestyles (and voting for politicians who take these challenges seriously), providing swift nest boxes may be another way people can help.

A campaign by Hannah Bourne-Taylor, a nature writer, to mandate the installation of “swift bricks” in new UK housing stock, could make up for the loss of nest sites in the eaves of older buildings – if only the government would support it.

Given all the difficulties swifts face and the joy that so many people derive in watching and listening to them careering across our summer skies, then we really should be supporting any efforts that may make a difference.

Alexander C. Lees, Reader, Manchester Metropolitan University

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

From May 15-17, 2024, American leaders including California Gov. Gavin Newsom and Massachusetts Gov. Maura Healy will be attending a global conference on environmental issues. The host? The Vatican.

The summit, “From Climate Crisis to Climate Resilience,” will focus on human adaptation, not just trying to mitigate climate change. “We need to embark on building climate resilience so that people can bend the emissions curve and bounce back from the climate crisis safer, healthier, wealthier to a sustainable world,” the Pontifical Academy of Sciences said in a statement announcing the workshop.

The Catholic Church might seem a surprising institution to convene a climate change event. But many saints, activists and religious leaders have called on their faith to inspire care for the Earth. Pope Francis in particular has been vocal about the risks of climate change, especially its impact on the world’s poorest and most vulnerable people.

Here are five aspects about Francis’ views – and Catholicism’s broader relationship with the environment – that scholars have written about for The Conversation.

1. God’s creation

Care for the Earth has a long Catholic lineage, dating back centuries.

“One of the basic beliefs of Christianity is that the material world was created directly by God, and thus fundamentally connected with God’s goodness,” explained Joanne M. Pierce, a religious studies scholar at College of the Holy Cross.

One saint who took that teaching to heart was Hildegard of Bingen, who died in the 12th century. A German expert on herbal medicines and botany, she was also a writer, and she “espoused a kind of ‘green’ theology, called viriditas.”

Another Catholic saint famous for his love of nature is Francis of Assisi, the patron saint of ecology: an Italian friar described as treating animals “with the same dignity as human beings.”

2. Faith – and reason

In fact, when Pope Francis published an encyclical on the environment in 2015, he took its title from one of his namesake saint’s poems: “Laudato si.”

The encyclical links concern for climate change with Catholic teachings. But it is not just meant for Catholics; Francis also makes science-based arguments that people can appreciate with or without religious faith, noted Lawrence Torcello, a philosopher at the Rochester Institute of Technology.

“Laudato si” is a notable “example of how reason ought to be incorporated into public discourse,” Torcello wrote. In a time as polarized as our own, arguments need to be framed in a way that anyone can understand, even if they don’t agree, “regardless of private religious or parochial commitments.”

3. An influential messenger

Similarly, University of Michigan business scholars Andrew Hoffman and Jenna White zoomed in on the pope’s ability to speak to people beyond divides: Catholics and non-Catholics, Republicans and Democrats, people who care deeply about climate change and others that are skeptical about it.

In the United States, they pointed out, debates over climate change are often more about worldviews than about scientific proof. “Calling on people to protect the global climate because it is sacred … will create far more personal commitment than a government call for action on economic grounds or an activist’s call on environmental grounds,” the pair wrote.

4. Environmental front line

Francis has often highlighted climate change’s unequal impact on people across the globe. That was on display in 2019, when the Vatican hosted a “Synod of the Amazon” – a region especially threatened by environmental destruction.

“As a theologian who studies religious responses to the environmental crisis, I find the pope’s effort to learn from the indigenous people of the Amazon noteworthy,” wrote University of Dayton professor Vincent Miller.

“Some might dismiss this synod as just a meeting,” he acknowledged. But “the Synod of the Amazon marks a significant shift from high-minded papal exhortations about taking climate action to a global religious community that gives voice to those living on the front lines of ecological destruction.”

5. Warnings and wonder

In 2023, Francis released an addendum to “Laudato Si.” Like the original document, it linked environmental, social and technological challenges – such as by rebuking wealthy countries and individualistic attitudes for ignoring climate change’s impact.

In the pope’s eyes, “all life exists in relationships,” wrote Lisa Sideris, an environmental ethicist at UC Santa Barbara: nature, human beings and the divine. “Francis’ social critique, I believe, stems from his vision of life – one filled with awe for the depth of meaning and mystery to be found in an interconnected world.”

Part of the problem, as Francis presents it, is that people have forgotten just how deeply bound together we are – a theme likely to be front and center at this week’s summit.

This story is a roundup of articles from The Conversation’s archives.

Molly Jackson, Religion and Ethics Editor, The Conversation

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

In 2017, then-Prime Minister Malcolm Turnbull alighted from a helicopter to announce a grand plan: Snowy Hydro 2.0. It would turn the famous hydroelectric scheme into a giant battery, ready to power the green transition.

Turnbull no doubt expected his announcement would associate his leadership with the positive aura of the enormous post-war Snowy scheme, since mythologised as the foremost nation-building achievement of the 20th century.

But bad press has plagued Snowy 2.0. Recent news of a tunnel collapse is the latest episode in ongoing mechanical problems. There have been reports of environmental mismanagement, bogged tunnelling machines and cost blowouts. The constant stream of bad stories have outweighed any nation-building glow.

Or has it? Snowy 1.0 took 25 years to complete. It was a huge task to divert the Snowy River inland through tunnels, bolstering water supplies in the Murray and Murrumbidgee rivers and generating power through hydroelectricity. Workers died. Costs blew out. But the mythology of the project grew, partly driven by promotional films depicting the project as a source of national pride and power.

A tale of two projects

Snowy 2.0 is overseen by a government-owned corporation, Snowy Hydro. Its public relations program includes social media, an onsite Discovery Centre and a YouTube channel with monthly video updates narrated by Snowy 2.0 personnel.

To date, the biggest boon for the project has been the three-part SBS series, Building the Snowy, first broadcast in August 2023. While not formally a product of Snowy Hydro, the series has an upbeat tone. Extensive use of archival footage strongly links current works to the celebrated post-war scheme.

Despite these efforts, Snowy 2.0 is now nationally known for slow progress and cost blowouts. The negative perception is fair. Snowy Hydro bosses admit there have been unanticipated setbacks.

Is it too late to change these perceptions? Not necessarily. Energy projects can be powerfully reimagined and legitimated in the public sphere. The original Snowy Scheme of the 1950s offers a formidable template.

This wasn’t by accident. Sir William Hudson, an engineer tasked with managing the Snowy scheme, had witnessed the successful promotion of Roosevelt’s 1930s New Deal policies in the United States, including the construction of the monumental Hoover Dam.

Hudson decided to follow suit, investing heavily in promotion. This, it turned out, was wise. The scheme’s early years were fraught. Political wrangling meant the scheme was started under Commonwealth defence powers until it was formalised by state legislation in Victoria and NSW in 1959. It could easily have been cancelled or curtailed.

As the building progressed, workers began to die in accidents – a tally which would reach 121. States continued to disagree about the allocation of water for irrigation.

Hudson had to convince both the public and politicians of its merits. In addition to the usual press releases and newsreels, Hudson turned the works into a tourist attraction, taking people into the mountains by the busload.

Documentaries by the dozen

From the 1950s to the 1970s, the Snowy Mountain Authority sponsored a prolific photographic section, which put out huge volumes of photos – and around 130 documentaries.

Some of these weren’t aimed at a wide audience, such as safety training films or recruitment films to sustain the workforce.

But there were dozens which deliberately set out to create a favourable image of the scheme. The experienced cinematographer Harry Malcolm produced many of these films, which were shown at film festivals, schools and community group screenings.

The films made much of the spectacular alpine environment. Some showed the lives and accommodation of workers and their families in company towns such as Khancoban and Cabramurra. Only a few mentioned the multicultural workforce the scheme is known for.

Titles include Where Men and Mountains Meet (1963), Challenge of the Great Divide (1967) and Where the Hills Are Twice as Steep (1958). This last features a male narrator speaking from the perspective of Mt Kosciuszko, describing a chronology from deep time to colonisation to the problems of irrigation and electricity the scheme was meant to solve.

A high point was Conquest of the Rivers (1957), which won awards at film festivals and circulating internationally.

The semi-fictionalised documentary tells the story of Tom Carpenter who leaves his drought-affected home west of the Great Dividing Range with his small family and travels to Cooma to work on the Snowy.

Conquest of the Rivers emphasises a better future, created by the labour of male bodies as they carve paths inside mountains. The film draws on wartime tropes of capable masculinity.

Taken together, these documentaries offered a stabilising discourse for the nation against the massive social change brought by the large Baby Boomer generation.

By 1960, the films had done their work. There was widespread enthusiasm for the project and its future was guaranteed.

There’s a telling quote from Tom Mitchell, a critic of the scheme, in Margaret Unger’s Voices from the Snowy:

In 1960 Upper Murray people suffered from a strange disease known as ‘Snowyitis’ which consisted of an overwhelming enthusiasm for the Snowy Scheme, almost rising to the fervour of a Billy Graham crusade. And yet, if asked, no one could really define the benefits

These films were never meant to be even-handed. Instead, Harry Malcolm’s films were a potent mix of truth and illusion, distracting from real problems such as deficient safety standards, low worker morale, and alarmingly, no planning for floods until after devastating floods on the Murray in 1956.

Could history repeat?

Just like the original Snowy scheme, the future of Snowy 2.0 is not assured. Its original backer has left politics. Enormous engineering challenges have yet to be overcome.

Could Snowy 2.0 be reframed as 1.0 did? It is possible. But it would require a much more imaginative storytelling regime, beyond photos of large tunnelling machines or commentary from engineers.

To make it successful in the public eye, it should harness the new story of our time – the essential energy transition away from fossil fuels and the creation of a new grid. It should connect this project in the mountains to the needs of people around the nation, appealing to the senses and conjuring up the desired future.

And it cannot be only in the realm of PR – Snowy 2.0 must make our environmental plight better, not worse.

Belinda Smaill, Professor of Film and Screen Studies, Monash University and Kate Fitch, Senior Lecturer, Communications and Media, Monash University

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

The summer of 2023 was the warmest in the non-tropical areas of the northern hemisphere for 2,000 years, a new study has shown.

Across this vast area of land, encompassing Europe, Asia and North America, surface air temperatures were more than 2°C higher in June, July and August 2023 than the average summer temperature between AD1 and 1890, as reconstructed from tree ring records.

While climate change is a global phenomenon, warming on a regional scale is often stronger. And it is regional climate change, not the global average temperature, that people experience.

The Paris agreement aims to limit climate change to below 2°C and ideally 1.5°C of warming, but these figures refer to global temperature change, usually averaged over 20 years. The authors of the new research argue that these targets have already been breached at a regional scale in the northern hemisphere summer.

There were 2,295 deaths associated with five heatwaves in summer 2023 in the UK. The authors of the new study wanted to understand how unusually warm the summer of 2023 was in the northern hemisphere compared with the past.

To do that, they turned to one of the most useful tools for taking Earth’s temperature over thousands of years: rings that grow annually in tree trunks anywhere on the planet where the climate is seasonal.

Two millennia of tree rings

The extreme warmth of 2023 was caused by greenhouse gas emissions and amplified by El Niño, the warm phase of a natural climate cycle in the Pacific Ocean.

To find out what the climate was like in the recent past, scientists analyse weather station records to see if a particular year was warmer or cooler than previous ones. The longest instrumental record available is the Central England Temperature series and that only goes back to 1659, which is not long enough to place recent warming in context.

To find out how warm it is now compared with two millennia ago, scientists use climate proxies. These are natural archives like ice cores and sediments that store a record of the climate in the layers they accumulate over time.

Trees grow in lots of different places and sensitively record past climate information for much of the globe. Trees grow one ring a year in seasonal climates, so there is no doubt about the date a particular ring formed.

To study past climate, tree ring scientists analyse how wide or narrow a ring is in a particular year, how dense the wood is or its chemical composition.

Tree-ring growth is sensitive to many climate variables, but in conifer trees growing at northern hemisphere treelines (the point at which trees can no longer grow due to cold temperatures, high winds or low moisture) it is summer temperature that most strongly controls tree ring growth. In a warm summer, such trees will tend to produce wide, dense rings.

A period in which trees from a particular region all grew wide, or narrow, rings, if accurately cross-referenced with many trees, indicates an unusual phase in the climate which affected the trees’ growth.

The authors of the new study were looking for trees which faithfully recorded past summer temperatures. They combined records from thousands of these trees across hundreds of sites in North America and Canada, the UK and Europe, Scandinavia, Russia, Mongolia and Japan. The tree ring records were produced by scientists working laboriously to take tree core samples, measure the rings and share the data.

This huge tree ring archive revealed that the northern hemisphere summer of 2023 was warmer than the average of every year between AD1 and 1890 by 2.2°C. When compared to the very coldest year of the last two millennia, AD536, when a large volcano erupted and cooled the planet for several years, summer 2023 was found to be nearly 4°C warmer than that year.

What will future forests show?

As greenhouse gas emissions rise, enhancing Earth’s greenhouse effect, people can expect more frequent and severe climate events. In the past, very warm years globally generally happened during El Niño events, such as in 2016.

However, greenhouse gas levels are now so high that, for the first time in 2017, the planet experienced a very warm year during El Niño’s opposite, the La Niña phase, which has a cooling effect on global temperatures.

The new study found that 2023 even broke the 2016 record as it was 0.23°C warmer than the last El Niño-amplified summer. Greenhouse gas emissions are now so high that, when climate records are broken, they break in large step changes, rather than small increments.

The thousands of trees sampled for this study, from mountain forests around the northern hemisphere, face increasingly tough growing conditions. Were the scientists to revisit them they would find, in many places, trees stressed by heat and drought.

A single drought between 2012 and 2016 in California killed more than 200 million trees. Tree deaths in France have increased by over 80% in the last decade, a pattern seen around the globe as a result of hotter droughts.

Forests contain 80% of biodiversity living on land and sustain the livelihoods of 1.6 billion people. Trees also regulate the global climate and store carbon from the air, while slowly building up a record in their rings of our failure to halt dangerous climate change.

The extreme heat of 2023 highlights the need for urgent climate action. If the world rapidly decarbonises, future scientists will hopefully see the climate’s recovery quietly recorded in the tree ring records of Earth’s remaining forests.

Don’t have time to read about climate change as much as you’d like?
Get a weekly roundup in your inbox instead. Every Wednesday, The Conversation’s environment editor writes Imagine, a short email that goes a little deeper into just one climate issue. Join the 30,000+ readers who’ve subscribed so far.

Mary Gagen, Professor of Physical Geography, Swansea University

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