Tag Archives for myths

Matt Canavan suggested the cold snap means global warming isn’t real. We bust this and 2 other climate myths


Steven Saphore/AAP

Nerilie Abram, Australian National University; Martin De Kauwe, UNSW, and Sarah Perkins-Kirkpatrick, UNSWSenator Matt Canavan sent many eyeballs rolling yesterday when he tweeted photos of snowy scenes in regional New South Wales with a sardonic two-word caption: “climate change”.

Canavan, a renowned opponent of climate action and proponent of the coal industry, appeared to be suggesting that the existence of an isolated cold snap means global warming isn’t real.

Prime Minister Scott Morrison has previously insisted there is “no dispute in this country about the issue of climate change, globally, and its effect on global weather patterns”. But Canavan’s tweet would suggest otherwise.

The reality is, as the climate warms, record-breaking cold weather is becoming less common. And one winter storm does not negate more than a century of human-caused global warming. Here, we take a closer look at the cold weather misconception and two other common climate change myths.

Myth #1: A cold snap means global warming isn’t happening

Canavan’s tweet is an example of a common tactic used by climate change deniers that deliberately conflates weather and climate.

Parts of Australia are currently in the grip of a cold snap as icy air from Antarctica is funnelled up over the eastern states. This is part of a normal weather system, and is temporary.

Climate, on the other hand, refers to weather conditions over a much longer period, such as several decades. And as our climate warms, the probability of such weather systems bringing record-breaking cold temperatures reduces dramatically.

Just as average temperatures in Australia have risen markedly over the past century, so too have winter temperatures. That doesn’t mean climate change is not happening. In a warming world, extremely cold winter temperatures can still occur, but less often than they used to.

In fact, human-caused climate change means extreme winter warmth now occurs more often, and across larger parts of the country. Record-breaking hot events in Australia now far outweigh record breaking cold events.

Extreme cold and warm winter temperatures in Australia
Percentage of Australia experiencing extreme cold (bottom 10%) and extreme warmth (top 10%) in winter since 1910. Data from the Bureau of Meteorology.

Myth #2: Global warming is good for us

Yes, climate change may bring isolated benefits. For example, warmer global temperatures may mean fewer people die from extreme cold weather, or that shorter shipping routes open up across the Arctic as sea ice melts.

But the perverse benefits that may flow from climate change will be far outweighed by the damage caused.

Extreme heat can be fatal for humans. And a global study found 37% of heat-related deaths are a direct consequence of human-caused climate change. That means nearly 3,000 deaths in Brisbane, Sydney and Melbourne between 1991 and 2018 were due to climate change.

Extreme heat and humidity may make some parts of the world, especially those near the Equator, essentially uninhabitable by the end of this century.

Global warming also kills plants, animals and ecosystems. In 2018, an estimated one-third of Australia’s spectacled flying foxes died when temperatures around Cairns reached 42℃. And there is evidence many Australian plants will not cope well in a warmer world – and are already nearing their tipping point.

Heatwaves also damage oceans. The Great Barrier Reef has suffered three mass bleaching events in just five years. Within decades the natural wonder is unlikely to exist in is current form – badly hurting employment and tourism.



Read more:
Climate change is making ocean waves more powerful, threatening to erode many coastlines

Myth #3: More CO₂ means Earth will definitely get greener

In January last year, News Corp columnist Andrew Bolt caused a stir with an article that suggested rising carbon dioxide (CO₂) emissions were “greening the planet” and were therefore “a good thing”.

During photosynthesis, plants absorb CO₂. So as the concentration of CO₂ in the atmosphere increases, some researchers predict the planet will become greener and crop yields will increase.

Consistent with this hypothesis, there is indirect evidence of increased global photosynthesis and satellite-observed greening. There is also indirect evidence of increased “carbon sinks”, whereby CO₂ is drawn down from the atmosphere by plants, then stored in soil.

Rising temperatures lead to an earlier onset of spring, as well as prolonged summer plant growth – particularly in the Northern Hemisphere. Researchers think this has triggered an increase in the land carbon sink.

However, there’s also widespread evidence some trees are not growing as might be expected given the increased CO₂ levels in our atmosphere. For example, a study of how Australian eucalypts might respond to future CO₂ concentrations has so far found no increase in growth.

Increased plant growth may also cause them to use more water, causing significant reductions in streamflow that will compound water availability issues in dry regions.

Overall, attempts to reconcile the various lines of evidence of how climate change will alter Earth’s land vegetation have proved challenging.

So, are we doomed?

After all this bad news, you might be feeling a bit dejected. And true, the current outlook isn’t great.

Earth has already warmed by about 1℃, and current policies have the world on track for at least 3℃ warming this century. But there is still reason for hope. While every extra bit of warming matters, so too does every action to reduce greenhouse gas emissions.

And there are promising signs of increasing ambition to reduce greenhouse gas emissions on the global front – from the United States, the United Kingdom, the European Union, Japan and others.

Unfortunately, Australia is far behind our international peers, instead pushing the burden of action onto future generations. We now need the political leadership to set our country, and the world, on a safer and more secure path. Ill-informed tweets by senior members of the government only set back the cause.



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Spot the difference: as world leaders rose to the occasion at the Biden climate summit, Morrison faltered


The Conversation

Nerilie Abram, Professor; ARC Future Fellow; Chief Investigator for the ARC Centre of Excellence for Climate Extremes; Deputy Director for the Australian Centre for Excellence in Antarctic Science, Australian National University; Martin De Kauwe, Senior lecturer, UNSW, and Sarah Perkins-Kirkpatrick, ARC Future Fellow, UNSW

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

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Does Australia really have the deadliest snakes? We debunk 6 common myths



A red-bellied black snake
Damian Michael, Author provided

Damian R. Michael, Charles Sturt University; Dale Nimmo, Charles Sturt University, and Skye Wassens, Charles Sturt University

As we settle into spring and temperatures rise, snakes are emerging from their winter hideouts to bask in the sun. But don’t be alarmed if you spot one, it’s hard to imagine a more misunderstood group of animals than snakes.

Our interactions with snakes are conversation starters, with yarns told and retold. But knowing what’s fact and fiction gets harder with each retelling.



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I’ve always wondered: who would win in a fight between the Black Mamba and the Inland Taipan?

As is so often the case with wildlife, the myths pale in comparison to what science has shown us about these incredible creatures. So let’s debunk six misconceptions we, as wildlife ecologists, often hear.

A snake warning sign
With snakes on the move this season, people and pets are more likely to spot them.
Shutterstock

1. Black snakes and blue tongue lizards keep brown snakes away

This is a common old wives’ tale in southern Australia. The myth goes that if you see a red-bellied black snake or a blue-tongue lizard on your property, you’re unlikely to see the highly venomous brown snake, because black snakes keep brown snakes at bay.

This myth probably originates from observations of black snakes eating brown snakes (which they do).

But it’s not one-way traffic. There are many reported examples of brown snakes killing black snakes, too. Overall, no scientific evidence suggests one suppresses the other.

There is also no evidence blue-tongue lizards prey upon or scare brown snakes. In fact, many snakes feed on lizards, including brown snakes which, despite a preference for mammal prey as adults, won’t hesitate to have a blue tongue for lunch.

2. Snakes are poisonous

While the term poisonous and venomous are often used interchangeably, they mean quite different things. If you eat or ingest a toxic plant or animal, it’s said to be poisonous, whereas if an animal stings or bites you and you get sick, it’s venomous.



Read more:
Why are some snakes so venomous?

Venom is a specialised type of poison that has evolved for a specific purpose. For venom to work, it needs a wound to enter the body and into the bloodstream. Snakes, therefore, are generally venomous, not poisonous.

But there are exceptions. For example, the American garter snake preys on the rough-skinned newt which contains a powerful toxin.

A black and red garter snake.
The toxins from the rough-skinned newt can stay in a garter snake’s liver for up to a month.
Steve Jurvetson/Wikimedia, CC BY

The newt’s toxin accumulates in the snake’s liver, and effectively makes this non-venomous snake species poisonous if another animal or human eats it. Remarkably, these snakes can also assess whether a given newt is too toxic for them to handle, and so will avoid it.

3. Australia has the deadliest snakes in the world

Approximately 20% of the world’s 3,800-plus snake species are venomous. Based on the median lethal dose — the standard measurement for how deadly a toxin is — the Australian inland taipan is ranked number one in the world. Several other Australian snakes feature in the top 10. But does that make them the deadliest?

It depends on how you define “deadly”. Death by snake bite in Australia is very uncommon, with just two per year, on average, compared to 81,000-138,000 deaths from snakes annually worldwide.



Read more:
Yes, Australian snakes will definitely kill you – if you’re a mouse

If we define “deadly snakes” as those responsible for killing many people, then the list would be topped by snakes such as the Indian cobra, common krait, Russell’s viper and the saw-scaled viper, which occur in densely populated parts of India and Asia.

A lack of access to antivenoms and health care contribute substantially to deaths from snake bites.

An Indian cobra upright on a log
Indian cobra’s are one of the deadliest snakes in the world.
Shutterstock

4. Snakes have poor eyesight

Compared to other reptiles, such as monitor lizards, most snakes have poor eyesight, especially species that are active at night or burrow in soil.

However, snakes that are active by day and feed on fast-moving prey have relatively good vision.

One study in 1999 showed people are less likely to encounter eastern brown snakes when wearing clothing that contrasted with the colour of the sky, such as dark clothing on a bright day. This suggests they can see you well before you see them.

Some snakes such as the American coachwhip can even improve their eyesight when presented with a threat by constricting blood vessels in the transparent scale covering the eye.

A sea snake dives underwater
An olive sea snake can actually detect light through their tail.
Shutterstock

And then there’s the olive sea snake, whose “phototactic tails” can sense light, allowing them to retract their tails under shelter to avoid predation.

5. Young snakes are more dangerous than adults

This myth is based on the idea juvenile snakes can’t control the amount of venom they inject. No evidence suggests this is true.



Read more:
Explainer: what should you do if you’re bitten by a snake?

However, research shows the venom of young and old snakes can differ. A 2017 study showed the venom of young brown snakes is different to adults, probably to facilitate the capture of different types of prey: young brown snakes feed on reptiles, whereas adult brown snakes predominantly feed on mammals.

But it’s not just age — venom toxicity can vary among individuals of the same population, or among populations of the same species.

A black snake with white stripes on a rock.
Bandy Bandy (Vermicella annulata). Defensive behaviours are often misinterpreted as aggression.
Damian Michael, Author provided

6. Snake are aggressive

Perhaps the most pervasive myth about snakes is they’re aggressive, probably because defensive behaviours are often misinterpreted.

But snakes don’t attack unprovoked. Stories of snakes chasing people are more likely cases where a snake was attempting to reach a retreat site behind the observer.

When threatened, many snakes give a postural warning such as neck flaring, raising their head off the ground, and opening their mouths, providing clear signals they feel threatened.

It’s fair to say this approach to dissuade an approaching person, or other animal, works pretty well.

Rhesus macaques display more fearful behaviour when confronted with snakes in a striking pose compared to a coiled or elongated posture. And showing Japanese macaques images of snakes in a striking posture sets of a flurry of brain activity that isn’t evoked when they’re shown images of snakes in nonthreatening postures.



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New research reveals these 20 Australian reptiles are set to disappear by 2040

The same is true for humans. Children and adults detect images of snakes in a striking posture more rapidly than a resting posture. And a study from earlier this year found human infants (aged seven to 10 months) have an innate ability to detect snakes.

Snakes are amazing, but shouldn’t be feared. If you encounter one on a sunny day, don’t make sudden movements, just back away slowly. Never pick them up (or attempt to kill them), as this is often when people are bitten.The Conversation

Damian R. Michael, Senior research fellow, Charles Sturt University; Dale Nimmo, Associate Professor in Ecology, Charles Sturt University, and Skye Wassens, Associate Professor in Ecology, Charles Sturt University

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

Why do brumbies evoke such passion? It’s all down to the high country’s cultural myth-makers


Pete Minard, La Trobe University

Brumby activists and environmentalists seem fundamentally unable to understand one another, despite having a lot in common. They share a love of the high country but are divided over the value or threat of wild horses.

Their mutual incomprehension has been fuelled by historically contested ideas about wildness, and the proper ways in which people should interact with and control the natural world.



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The grim story of the Snowy Mountains’ cannibal horses

Wild horses first appeared in Australia soon after colonisation, as horses escaped or were abandoned. According to historian Eric Rolls, brumbies may have originally got their name from the horses that Private James Brumby abandoned in 1804 when he was transferred from New South Wales to Tasmania. Alternatively, the 19th-century pastoralist E. M. Curr suggested that “brumby” may be a corruption of booramby, a Bidjara word for “wild”.

Whatever the origin of the word, pastoral expansion spread brumbies to all corners of Australia during the 19th century.

Settled colonial farmers hated brumbies, viewing them as symbols of the waste and destruction caused by the pastoral industry that the settlers were rapidly displacing. Brumbies also destroyed fences and competed with stock for grass.

Brumbies were destroyed en masse as pests, which also allowed farmers to make a profit from their hides and manes. Sometimes brumbies were even rendered for hog feed. In 1870, the Queanbeyan Age reported that wild horses were “hated and shot by all”. Five years later, it predicted that as Australia’s population increased, pastoralists would lose control of the fine country “where now the wild horse holds almost undisputed sway” to industrious settled farmers.

By the turn of the 20th century, when Banjo Paterson was writing about his pastoralist friends in the Snowy Mountains, the decline of both pastoralism and wild horses was well underway. Paterson’s work is full of a self-conscious nostalgia for a wilder, freer Australia that he knew was under threat.

In Images of Australia, Paterson wrote of remembering the transition from free-roaming pastoralism to fenced farming as the moment when “the few remaining mobs of wild horses were run down and impounded”. His idea of the Snowy Mountains as a special place reflecting a disappearing Australia, and of brumbies embodying this specialness, has become culturally important for high country locals.

Brumbies and war

The high country bush legend has been used to argue that the mountain country produced excellent mounted fighting forces during the first world war. Snowy Mountain men certainly enlisted in the Australian Light Horse Regiment and some of them may have supplied their own horses, which could conceivably have come from brumby stock.

But there was no wholesale supply of brumbies for war service. Australia did provide many horses during WWI, but they were Walers, a distinctive Australian breed that was well suited to carrying troops in hot and dry conditions. Australian breeders tasked with supplying horses for the war effort regarded brumby stallions as mongrels that should not be allowed to pollute their bloodlines. The president of the National Agricultural Association of Queensland, Ernest Baynes, went as far as to say that the only way to make brumbies useful for the war effort would be to slaughter and export them “to the countries in which people eat horse, and are glad to get it”.

After the second world war, the historian, children’s novelist and high country local Elynne Mitchell further popularised brumbies through her series of Silver Brumby novels. Her work, along with the resurgence of Paterson’s popularity and the inaccurate memorialisation of the Light Horse Brigade, led to the further romanticisation of brumbies and the forgetting of farmers’ earlier antagonistic and utilitarian views of wild horses.

The romantic brumby became a symbol of local identity, of the high country’s way of life and of resistance to state control.



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Hold your horses – brumby fertility control isn’t that easy

Gradually increasing government control of the high country led to a decline in cattle grazing in alpine areas, more tourism, scientific study, and the end of licensed brumby running in 1982. This process alienated locals who could no longer experience nature as a working landscape. Instead, state control privileged visitors who passively admired the landscape and scientists who rightly worried about the environmental degradation caused by horses.

The ConversationSuccessive governments centralised the control of land, and could not see the local brumby culture. This blindness has led people such as fifth-generation local Leisa Caldwell to feel that the “mountain community has been kicked in the guts over and over. They’ve had their cattle taken, their towns flooded for the Snowy Mountains Hydro Scheme and their history destroyed. The last bit of history to show they even existed is the brumbies. If they go, what’s left?”

Pete Minard, Honorary Research Fellow, Centre for the Study of the Inland, La Trobe University., La Trobe University

This article was originally published on The Conversation. Read the original article.

Bigfoot, the Kraken and night parrots: searching for the mythical or mysterious



File 20170421 12655 110r77u
In 2012 scientists succeeded in filming for the first time ever a giant squid in its natural habitat.
EPA/NHK/NEP/DISCOVERY CHANNEL/AAP

Euan Ritchie, Deakin University

It’s remarkable how little we know about Earth. How many species do we share this planet with? We don’t know, but estimates vary from millions to a trillion. In some respects we know more about the Moon, Mars and Venus than we do about the ocean’s depths and the vast sea floors. The Conversation

But humans are inquisitive creatures, and we’re driven to explore. Chasing mythical or mysterious animals grabs media headlines and spurs debates, but it can also lead to remarkable discoveries.

The recent photographing of a live night parrot in Western Australia brought much joy. These enigmatic nocturnal birds have been only sporadically sighted over decades.

Another Australian species that inspires dedicated searchers is the Tasmanian tiger, or thylacine. A new hunt is under way, not in Tasmania but in Queensland’s vast wilderness region of Cape York.

This is the first photograph of a live night parrot, taken in Western Australia in March 2017.
Bruce Greatwitch

Other plans are afoot to search for the long-beaked echidna in Western Australia’s Kimberley region.

In the case of the thylacine, old accounts from the region that sound very much like descriptions of the species raise the prospect that perhaps Cape York isn’t such a bad place to look after all.

But in reality, and tragically, it’s very unlikely that either of these species still survives in Australia. For some species there is scientific research that estimates just how improbable such an event would be; in the case of thylacines, one model suggests the odds are 1 in 1.6 trillion.

Chasing myths

The study and pursuit of “hidden” animals, thought to be extinct or fictitious, is often called cryptozoology. The word itself invites scorn – notorious examples include the search for Bigfoot, the Loch Ness Monster or Victoria’s legendary black panthers.

The search for Bigfoot is an extreme case of cryptozoology.

Granted, it’s probably apt to describe those searches as wild goose chases, but we must also acknowledge that genuine species – often quite sizeable ones – have been discovered.

Remarkable discoveries of animals thought to be fantasies or long extinct include giant squid, mountain gorillas, okapi, Komodo dragons and coelacanths.

In some cases, like the giant squid, these animals have been dismissed as legends. The reclusive oarfish, for example, are thought to be the inspiration for centuries of stories about sea serpents.

Oarfish can grow up to 8 metres long and swim vertically through the water. Commonly inhabiting the deep ocean, they occasionally come to shallow water for unknown reasons.
AAP Image/ Coastal Otago District Office

Technology to the rescue

Finding rare and cryptic species is self-evidently challenging, but rapid advances in technology open up amazing possibilities. Camera traps now provide us with regular selfies of once highly elusive snow leopards, and could equally be used with other difficult-to-find animals.

Candid camera, snow leopards in the Himalayas.

Environmental DNA is allowing us to detect species otherwise difficult to observe. Animal DNA found in the blood of leeches has uncovered rare and endangered mammals, meaning these and other much maligned blood-sucking parasites could be powerful biodiversity survey tools.

Acoustic recording devices can be left in areas for extended time periods, allowing us to eavesdrop on ecosystems and look out for sounds that might indicate otherwise hidden biological treasures. And coupling drones with thermal sensors and high resolution cameras means we can now take an eagle eye to remote and challenging environments.

Drones are opening up amazing possibilities for biological survey and wildlife conservation.

The benefits of exploration and lessons learned

It’s easy to criticise the pursuit of the unlikely, but “miracles” can and do occur, sometimes on our doorstep. The discovery of the ancient Wollemi pine is a case in point. Even if we don’t find what we’re after, we may still benefit from what we learn along the way.

I’ve often wondered how many more species might be revealed to us if scientists invested more time in carefully listening to, recording and following up on the knowledge of Indigenous, farming, and other communities who have long and intimate associations with the land and sea.

Such an approach, combined with the deployment of new technologies, could create a boom of biological discovery.

Euan Ritchie, Senior Lecturer in Ecology, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University

This article was originally published on The Conversation. Read the original article.

How much does wind energy cost? Debunking the myths


Dylan McConnell, University of Melbourne

Are renewables pushing up the cost of electricity? That’s the claim made by Alan Moran in an opinion piece for the Australian Financial Review this week.

Moran, executive director of Regulation Economics and a former director at the Institute of Public Affairs, argues that increasing investment in renewables and particularly wind energy will cost consumers billions of dollars. The high operating costs and requirements for backup when the wind isn’t blowing are the problem, he argues.

But the evidence actually suggests the opposite: wind energy is already competitive with fossil fuels, will reduce electricity prices for consumers, and will play a large role in reducing Australia’s greenhouse gas emissions.

So, let’s go through Moran’s claims one by one.

Claim: [W]indfarms […] need three times the price at which Australian coal generators can supply electricity. Australia’s coal resources are so abundant that across the eastern states that they can profitably supply electricity at a cost of $40 a MWh. Windfarms require $120 a MWh.

It is true that black coal can supply electricity to the wholesale market at A$40 per megawatt hour (MWh). However, new wind farms require much less than A$120 per MWh to be financed. Recent experience shows that new wind farms require A$80-90 per MWh.

But this is comparing apples with oranges. The coal cost refers to what is essentially the cost of fuel. The wind cost is the cost over the lifetime of the project, including capital and return on investment.

If we compare apples with apples, the long-run cost of coal is A$85-$100 per MWh (without a carbon price), versus A$90 per MWh for wind. The short-run cost of wind is zero: flowing air costs nothing.

Claim: [B]ecause wind generated supply is intrinsically unreliable it needs back-up in the form of fast start generators […] Wind/solar generation in Australia currently has a 7% share of supply. That level requires 6 per cent in additional back-up, according to the estimates by the Australian Energy Market Operator.

This statement implies that additional capacity has had to be installed because of wind. This is demonstrably not true. The Australian Energy Market Operator has stated that there is no new capacity required in the next 10 years, despite the increase in wind and solar.

South Australia is a good example. More than 1,200 megawatts of wind power capacity has been installed, but virtually no new gas plants have been built as “backup”. In the chart below you can see that on the afternoon and evening of Sunday June 7, wind and gas met all electricity demand in South Australia.

Generation by fuel type in South Australia on Sunday the 7th of June 2015. Operations at the Northern Power Station were shut down after an explosion at around midday.

More broadly, redundant capacity is important in the entire electricity system (not just wind). All types of generation have planned and unplanned shortages.

Unplanned outages are more challenging. If a whole generator goes offline, the system must return to normal within five minutes. This is often achieved with a “fast start” generator such as a gas turbine or hydro plant. These contingency plans must equal the loss of the largest generator in the system, usually coal.

No technology is 100% reliable, as illustrated in the graph above. Wind is really quite predictable and reliable compared to coal.

Claim: Wind turbine development has been improved over the past 20 years but is now approaching its theoretical maximum efficiency. It will never be remotely price competitive with conventional generators notwithstanding wishful thinking.

As I’ve shown above, wind is already competitive with new-build coal (and gas) in Australia, and many other places around the world (including the United States). Carbon policy aside, some of the assets are seriously old and are going to be retired anyway.

A new study from UNSW Australia looked at the best energy mix for generation. Even without a carbon price, the research found that the lowest cost mix in 2050 sources only 30% of electricity from gas, with the rest supplied by renewables. About half of the gas capacity is Open Cycle Gas Turbines (for peak demand) that supply very small quantities of energy.

Claim: In aggregate terms, the annual impost on electricity consumers [of the Renewable Energy Target] is therefore from the 33,000GWh and means a cost to the customer of $3 billion a year […]

As I’ve written before on The Conversation, the government’s own modelling shows a net saving to consumers (and so does plenty of other analysis). The ACIL Allen analysis finds the target will cut power bills from 2021 onwards (by up to A$91 per year by 2030) and deliver a net saving to consumers.

Claim: Energy only comprises 25 to 30 per cent of emissions and Australia’s renewable target might therefore reduce emissions by 4 to 5 per cent.

According the Climate Change Authority’s review of the Renewable Energy Target (RET), the RET is projected to reduce Australia’s overall emissions by 58 million tonnes of CO2-equivalent.

The Government’s latest estimate of Australia’s emissions reduction task between 2015 and 2020 is 421 million tonnes. So between 2015 and 2020 alone, the RET achieves at least 13% of the reduction task.

The Conversation

Dylan McConnell is Research Fellow, Melbourne Energy Institute at University of Melbourne.

This article was originally published on The Conversation.
Read the original article.