Extreme weather leads to public health crises – so health and climate experts must work together

Aparna Lal, Australian National University and Rebecca Colvin, Australian National University

This year has seen a number of extreme weather events around the globe, from hurricanes in the Americas to devastating flooding in South Asia. The loss of lives, homes and livelihoods are made worse by subsequent disease outbreaks: after the South Asian floods, more than 12,000 cases of watery diarrhoea were reported in Bangladesh. Presumably, many more cases are unreported.

As our climate changes, severe weather events (especially intense rainfall) will become the “new normal”. The connection between climate and disease is well established, even in less extreme situations.

Read more: Irma and Harvey: very different storms, but both affected by climate change

This makes it vital that our meteorologists, climate scientists and health systems work closely together. Particularly, health professionals should make better use of weather forecasts to proactively manage disease risk. Climate outlooks – with a longer-term perspective than weather forecasts – can also help with long-range tactical and strategic planning.

The link between climate change and disease

Climate change projections consistently indicate increased climate variability. A more variable climate creates conditions for the spread and control of infectious disease. In particular, changes in the intensity and duration of rain can help spread pathogens through water.

Both floods and droughts can increase waterborne infections, either when clean and dirty water mix during floods, or through inadequate storage and concentration of toxic organisms when water is scarce.

Read more: Flooding from Hurricane Harvey causes a host of public health concerns

These risks are not restricted to countries with limited resources. In Australia, fluctuations in the sea surface temperatures in the Indian Ocean (a phenomenon shown by the “Indian Ocean Dipole”) are linked to spikes in rates of waterborne diseases like cryptosporidiosis, which cause gastrointestinal illness.

NSW Health documents, obtained earlier this year by the ABC, reveal that more than 100,000 NSW residents were issued protective boil-water alerts in the past five years. These residents lived in areas where pathogens like cryptosporidium were found in unfiltered drinking water pumped from rivers, lakes and dams. A more variable climate can increase these risks.

Research suggests we can improve public health outcomes by integrating both climate dynamics and the impact on human health into our management of natural water resources.

We need integrated climate and health systems

Traditional disease surveillance systems rely on early detection of illnesses as they occur, not predicting them before they happen. But outbreaks that follow extreme events are already underway before authorities are notified.

The close relationship between climate signals and some waterborne diseases suggest that advances in numerical weather forecasting and climate science present new opportunities for public health officials.

Read more: How satellites can help control the spread of diseases such as Zika

Forecasting based on climate variables is well established in crop disease management and ecosystem conservation.

Recent technological advancements, such as real-time predictions of disease outbreaks, highlight great potential for forecasting to be used for human health benefit ahead of extreme weather events.

Collaboration is key

At present, health professionals and climate forecasters generally operate separately from each other, as very distinct professions. This can make it very difficult for researchers, public servants and service providers to work effectively together.

Our experience at the ANU Climate Change Institute has taught us that an important early step to fostering cooperation is helping individuals build relationships.

Read more: We’ve got to stop meeting like this

It’s important to create opportunities for people from different sectors to come together so they can exchange knowledge and make personal connections. Emphasising that health and climate experts have many shared goals can help encourage new cross-sector networks and a sense of a shared professional identity. (And realistically, one of the most important things you can do to promote productive exchanges is feed people well.)

There’s a real opportunity to integrate health and climate knowledge bases. This could be what’s known as a “boundary object”: something that can be meaningfully interpreted by people with different training and backgrounds, which helps to span the “boundary” between these sectors or disciplines.

We stand to gain from integration across climate and health

As our understanding of climate patterns grows, there are more opportunities for the health sector to take advantage of sophisticated modelling and prediction.

This is particularly true if disease surveillance and climate and weather forecasting can be combined to assess health risks ahead of extreme weather events, rather than during or after the fact.

The ConversationBy fostering collaboration and the integration of the health and climate sectors, we can improve our capacity to respond to the health risks posed by climate change.

Aparna Lal, Research Fellow, Australian National University and Rebecca Colvin, Knowledge Exchange Specialist, Australian National University

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


How climate change affects the building blocks for health

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More intense rainfalls have caused flooding throughout New Zealand, as seen here in Northland.
from http://www.shutterstock.com, CC BY-ND

Alistair Woodward

In August last year, a third of the residents of the North Island township Havelock North fell acutely ill with gastroenteritis after their water was contaminated with campylobacter.

Following a long dry spell, the heaviest daily rainfall in more than ten years had washed the pathogenic organism from sheep faeces into the aquifer that supplies the town’s drinking water. The Havelock North supply, like many in rain-rich New Zealand, was not treated with chlorine or other disinfectants, and this was the country’s largest ever reported outbreak of waterborne disease.

This is just one example of how climate change may affect our health, according to a report released by the Royal Society of New Zealand today.

Prerequisites for good health

It turns out that the Goldilocks rule – “not too hot, not too cold” – applies to more than porridge. There have been many reports, such as those published by the Intergovernmental Panel on Climate Change and the Lancet Commission on Climate Change, that detail how aspects of human physical and mental are effected by a changing climate.

There is an optimum climate, related usually to what is most common or familiar. Deviations, especially if substantial and rapid, are risky.

Read more: Climate change set to increase air pollution deaths by hundreds of thousands by 2100

The RSNZ report is organised around eight prerequisites for good health, including community, shelter, water and food – all of which are threatened by climate change.

Building Blocks of Health Disrupted by Climate Change.
Royal Society of New Zealand

The building block metaphor is apt. It is unlikely that climate change will undermine health in new and unexpected ways. Instead we expect it to act as a threat multiplier. Where there are weaknesses in the foundations of public health, rapid changes in temperatures, rainfall and sea levels will magnify damaging effects.

Direct and indirect effects

The impacts will include direct effects. More intense rainfall, especially on the western side of the country, will test health protection systems, as in the case of Havelock North.

But the impacts may also be indirect. The RSNZ report points out that changes in the climate may disrupt ecosystems, with knock-on effects for human health. As water temperatures rise, algal blooms occur more frequently, and human pathogens such as the vibrio species are found in higher concentrations.

There may be more intense exposure to pollen and other allergens, a particular concern given the relatively high rates of asthma that apply in New Zealand.

Read more: Can we blame climate change for thunderstorm asthma?

A reliable supply of food is one of the most important ecosystem services. The global food system is simultaneously more productive than ever before, and also exquisitely vulnerable. We depend more and more on a small number of crops, grown in mono cultures on larger scale and in fewer locations, dependent on longer supply chains and frequently requiring irrigation and heavy use of artificial fertilisers.

Climate change threatens the production and distribution of food in many ways. For instance, the rice crop in southern China currently fails due to high temperature stress once every century or longer, but this will be a once-in-10-year event with 2–3°C global warming, and once every four years if average temperatures rise by 5–6°C.

Effects on mental health

Climate change also acts through social stressors. Rising sea levels, combined with heavy rainfall, threaten many settlements around the New Zealand coast and elsewhere. The community of South Dunedin is one of the most vulnerable.

On a broader scale, internationally, it is projected climate change will displace very large numbers of people. The recent flood of refugees to Europe (sparked, in part, by climate extremes) illustrates the detrimental effects to security, community cohesion and health that may result.

The RSNZ report acknowledges that it is not just physical health that is important. Depression, anxiety, grief and other manifestations of loss and conflict may occur when familiar environments are damaged and social connections threatened. This is most evident following disasters such as droughts and floods.

The report refers to the particular threat climate change poses to Māori. Not only are Māori over-represented amongst those with low incomes, and at greater risk therefore of poor health from hazardous environments. Māori culture also embodies a strongly developed sense of relationship with place that carries with it responsibility and obligations. Climate change challenges this guardianship role.

Transition risks and opportunities

There is another dimension to health impacts that is not discussed in the RSNZ report. I refer to the damage that may be caused by the way we respond to climate change. Mark Carney, governor of the Bank of England, calls them “transition risks”. These are not trivial concerns, Carney says, because managing climate change successfully will require radical change, and the implications may be far reaching.

Expanded use of biofuels might compete with food crops, for instance. Carbon- pricing regimes may also aggravate food insecurity in the poorest populations. In low-income countries, reducing numbers of livestock to control methane emissions might be detrimental unless there are alternative sources of protein, energy and nutrients.

However, there are opportunities, too. The co-benefits agenda gets only a brief mention in the RSNZ report, which is a pity, since win-win interventions may provide a politically palatable route to substantial cuts in greenhouse emissions. For example well designed, comprehensive taxes on food could avoid a billion tons of greenhouse gas emissions and also prevent half a million premature deaths each year.

This is particularly relevant to New Zealand and Australia as most of the gains would be made by cutting the consumption of red meat in rich countries.

The Royal Society report concludes that more research is needed to better quantify the health impacts of climate change. This is true, of course. But we know enough already about risks to pay close attention to potential solutions. The big question, in my view, is how we take carbon out of the New Zealand economy, rapidly, and in an equitable fashion, without disrupting the building blocks of health.

The ConversationMaybe we can do better than avoiding harm. Transport, agriculture, urban form, food systems – in these areas, and others, there are substantial opportunities as well as serious risks.

Alistair Woodward, Professor

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

What whales and dolphins can tell us about the health of our oceans

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Dolphins contribute important knowledge about ocean health.

Stephanie Plön, Nelson Mandela University

From the poles to the equator, marine mammals such as seals, dolphins and whales, play an important role in global ecosystems as apex predators, ecosystem engineers and even organic ocean fertilisers. The ocean off the coast of South Africa is home to a high diversity of these mammals and is recognised as a global marine biodiversity hotspot.

Marine mammals are often referred to as “sentinels” of ocean health. Numerous studies have explored the effects of both noise and chemical pollution, habitat degradation, changes in climate and food webs on these marine apex predators. Yet the interplay of these factors isn’t well understood.

Our research on the unfortunate dolphins incidentally caught in shark nets off South Africa’s KwaZulu-Natal coast has helped fill in some of the gaps. By assessing the health of these dolphins we have provided valuable baseline information on conditions affecting coastal dolphin populations in South Africa. This is the first systematic health assessment in incidentally caught dolphins in the Southern Hemisphere.

But to gain a fuller picture of the health of marine mammals in these waters I am now combining this contemporary field research with historical data, like the collection at the Port Elizabeth Museum Bayworld.

The combination of data on diet, reproduction, population structure and health helps us gain a better understanding of the pressures and changes these apex predator populations face. And it helps us understand it in relation to global change, including both climate change and pressures brought about by human behaviour.

My research sheds light on multiple factors: pollutant levels, parasites, and availability of prey, all have an impact on individuals as well as populations.

Understanding the health of these animals also gives us insight into the state of the world’s oceans. This is relevant because oceans affect the entire ecosystem including food security, climate and people’s health. This degree of connectedness is highlighted by recent discoveries about how whales act as ecosystem engineers.

The accumulation of this knowledge is important because the planet’s oceans aren’t being protected. Recent popular documentaries such as “Sonic Sea” and “Plastic Ocean” have highlighted their exploitation and pollution.

What’s missing

Without baseline knowledge it’s challenging to establish the potential effects that new anthropogenic developments (those caused by human behaviour) have on local whale and dolphin populations.

For example, we know that whales are sensitive to shipping noise, so what potential impact could a new deep water port have on mothers and their calves? Could it drive them away from these nursery areas, or could it lead to an increased risk of whales and ships colliding? To answer this and monitor the change that a new port brings with it, we are investigating the soundscape of two bays in the Eastern Cape (one with a new port, one without) in parallel with baleen whale mother-calf behaviour.

Another example is understanding how changes in the Sardine run over the past 15 years have affected the diets of these mammals. The Sardine run is an annual phenomenon when large shoals of Sardine migrate northwards along the coast into KwaZulu-Natal waters to spawn. Using long-term data and samples from the Port Elizabeth Museum research collection, we have been able to establish that over the the past 20 or so years the main predator in the Sardine run – the long-beaked common dolphin – has shifted its diet to mackerel. Although such changes in diet can have potential impacts on the health of the dolphins, parallel investigations on the trophic level these animals feed at (using isotope data from teeth) and the body condition of the dolphins (using long-term data on blubber thickness), indicated no adverse effects to the dolphins.

Our analysis highlights how marine mammals may be used as indicators of environmental change and why research is important.

Finding answers to intricate questions on environmental change is not always easy. But a better understanding and knowledge of the environment these animals live in has to be incorporated into studies contributing to their conservation and management. Such studies are becoming increasingly relevant as they highlight the fast degradation of the marine environment.

For example, a recent study identified antibiotic resistant bacteria in both sea water samples and exhaled breath samples from killer whales. This suggests that the marine environment has been contaminated with human waste which in turn has significant medical implications for humans.

Gaining such information is particularly important given the rapid changes taking place in the oceans, such as those on South Africa’s southern and eastern coastline. This includes increasing coastal development, new deep water ports being built or expanded, and parts of the deep sea being explored for oil and gas.

To assess these changes and what they mean for the environment, baseline studies need to be carried out so that potential effects can be assessed. Whales and dolphins are increasingly being recognised as indicators of ocean health in this endeavour.

And a continuation of the research we did on dolphins caught in nets will help document the cyclic changes that can be seen as normal variation in a population. This could prove important for assessing future catastrophic events, such as the Deep Horizon oil spill.

What next

The oceans absorb over 25% of the world’s carbon pollution as well as heat generated by global warming. They also produce at least 50% of the planet’s oxygen, and are home to 80% of all life on earth. Yet only 5% of this vital component of our planet has been explored.

The ConversationResearch on whales and dolphins contributes important knowledge about ocean health. Historical data increasingly provides a guideline to teasing out natural variations in populations and assessing the contribution that multiple factors have on these animals. In time, this will ensure that policy makers are being given sound scientific information. It will also provide us with a good barometer of the overall health of our oceans.

Stephanie Plön, Researcher, Earth Stewardship Science Research Institute, Nelson Mandela University

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

Drones help scientists check the health of Antarctic mosses, revealing climate change clues

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Mosses are sensitive to even minor changes in their living conditions.
Sharon Robinson, Author provided

Zbyněk Malenovský, University of Tasmania and Arko Lucieer, University of Tasmania

Drones are helping scientists check the health of Antarctic mosses, revealing clues on the pace of climate change.

The scientists say their method could be used for similar research in other harsh environments like desert or alpine regions.

Mosses are sensitive to even minor changes in their living conditions, and scientists traditionally tramped through difficult terrain to collect data on them.

Using the specially-designed drones is faster, kinder to the environment and delivers detailed images that satellite imagery cannot match.

Drones also allow to map much larger areas than previously possible, showing how the moss health responds to meltwater in real time.

The ConversationThese methods could be used for similar research in other harsh environments like desert or alpine regions.

Zbyněk Malenovský, Researcher in Remote Sensing of Vegetation, University of Tasmania and Arko Lucieer, Associate Professor in Remote Sensing, University of Tasmania

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

Tweet streams: how social media can help keep tabs on ecosystems’ health

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Social media posts, such as this image uploaded to Flickr, can be repurposed for reef health monitoring.
Sarah Ackerman/Flickr/Wikimedia Commons, CC BY

Susanne Becken, Griffith University; Bela Stantic, Griffith University, and Rod Connolly, Griffith University

Social media platforms such as Twitter and Instagram could be a rich source of free information for scientists tasked with monitoring the health of coral reefs and other environmental assets, our new research suggests.

Ecosystems are under pressure all over the world, and monitoring their health is crucial. But scientific monitoring is very expensive, requiring a great deal of expertise, sophisticated instruments, and detailed analysis, often in specialised laboratories.

This expense – and the need to educate and engage the public – have helped to fuel the rise of citizen science, in which non-specialist members of the public help to make observations and compile data.

Our research suggests that the wealth of information posted on social media could be tapped in a similar way. Think of it as citizen science by people who don’t even realise they’re citizen scientists.

Read more: Feeling helpless about the Great Barrier Reef? Here’s one way you can help.

Smartphones and mobile internet connections have made it much easier for citizens to help gather scientific information. Examples of environmental monitoring apps include WilddogScan, Marine Debris Tracker, OakMapper and Journey North, which monitors the movements of Monarch butterflies.

Meanwhile, social media platforms such as Facebook, Twitter, Instagram and Flickr host vast amounts of information. While not posted explicitly for environmental monitoring, social media posts from a place like the Great Barrier Reef can contain useful information about the health (or otherwise) of the environment there.

Picture of health? You can learn a lot from holiday snaps posted online.
Paul Holloway/Wikimedia Commons, CC BY-SA

Twitter is a good resource for this type of “human sensing”, because data are freely available and the short posts are relatively easy to process. This approach could be particularly promising for popular places that are visited by many people.

In our research project, we downloaded almost 300,000 tweets posted from the Great Barrier Reef between July 1, 2016 and March 17, 2017.

After filtering for relevant keywords such as “fish”, “coral”, “turtle” or “bleach”, we cut this down to 13,344 potentially useful tweets. Some 61% of these tweets had geographic coordinates that allow spatial analysis. The heat map below shows the distribution of our tweets across the region.

Tweet heat map for the Great Barrier Reef.
Author provided

Twitter is known as place for sharing instantaneous opinions, perceptions and experiences. It is therefore reasonable to assume that if someone posts a tweet about the Great Barrier Reef from Cairns they are talking about a nearby part of the reef, so we can use the tweet’s geocoordinates as indicators of the broad geographic area to which the post is referring. Images associated with such tweets would help to verify this assumption.

Our analysis provides several interesting insights. First, keyword frequencies highlight what aspects of the Great Barrier Reef are most talked about, including activities such as diving (876 mentions of “dive” or “diving”, and 300 of “scuba”), features such as “beaches” (2,909 times), and favoured species such as “coral” (434) and “turtles” (378).

The tweets also reveal what is not talked about. For example, the word “bleach” appeared in only 94 of our sampled tweets. Furthermore, our results highlighted what aspects of the Great Barrier Reef people are most happy with, for example sailing and snorkelling, and which elements had negative connotations (such as the number of tweets expressing concern about dugong populations).

Casting the net wider

Clearly, this pool of data was large enough to undertake some interesting analysis. But generally speaking, the findings are more reflective of people’s experiences than of specific aspects of the environment’s health.

The quality of tweet information with regard to relevant incidents or changes could, however, be improved over time, for example with the help of a designated hashtag system that invites people to post their specific observations.

Read more: Survey: two-thirds of Great Barrier Reef tourists want to ‘see it before it’s gone’.

Similar alert systems and hashtags have been developed for extreme events and emergency situations, for example by the New South Wales Fire Service.

Tweets also often contain photographs – as do Instagram and Flickr posts – which can carry useful information. An image-based system, particularly in cases where photos carry time and location stamps, would help to address the lack of expertise of the person posting the image, because scientists can analyse and interpret the raw images themselves.

The Great Barrier Reef is, of course, already extensively monitored. But social media monitoring could be particularly beneficial in countries where more professional monitoring is unaffordable. Popular destinations in the Pacific or Southeast Asia, for example, could tap into social media to establish systems that simultaneously track visitors’ experiences as well as the health of the environment.

The ConversationWhile it is early days and more proof-of-concept research is needed, the technological possibilities of Big Data, machine learning and Artificial Intelligence will almost certainly make socially shared content a useful data source for a wide range of environmental monitoring in the future.

Susanne Becken, Professor of Sustainable Tourism and Director, Griffith Institute for Tourism, Griffith University; Bela Stantic, Professor, Director of Big data and smart analytics lab, Griffith University, and Rod Connolly, Professor in Marine Science, Griffith University

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

Explainer: what is tularemia and can I catch it from a possum?

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Researchers have found Australia’s first confirmed case of tularemia in a ringtail possum.
Andrew Mercer/flickr, CC BY-NC-SA

John-Sebastian Eden, University of Sydney

Tularemia is a disease that affects humans and other animals. It is caused by infection with the bacterium Francisella tularensis and is commonly spread by biting insects or by direct contact with an infected animal.

Human infection is less common than infection in small animals like rabbits and rodents. But it is important human cases are recognised and diagnosed quickly because without appropriate treatment the disease can be life-threatening.

Our team has recently confirmed its presence in Australia in samples taken from ringtail possums who died in two outbreaks in early 2000.

While this is clearly a newly identified risk to public health, it’s important to recognise how rare the disease is and how well the infection responds to treatment.

How is it transmitted to humans?

Tularemia is a “zoonotic disease”, an animal disease that can be transmitted to humans. The most common way someone might be infected is by being directly exposed to an infected animal through a bite or scratch, or even handling infected tissue, like when hunters skin animals.

Further reading: First Hendra, now bat lyssavirus, so what are zoonotic diseases?

Human infections can also occur indirectly from an animal through a biting insect vector, like ticks or deer flies. So, a fly might feed on an infected animal then also bite a human, transferring the bacterium via its mouth parts.

Humans can also catch the disease from animals by coming into contact with environmental sources such as water or soil that have been contaminated by an infected carcass. The bacteria might then infect humans through the eye, or an open wound, or even if digested from contaminated food.

How rare is tularemia in humans?

Fortunately, human cases of tularemia are relatively rare and appear to be limited to the Northern Hemisphere. Yet, even in the US, where the disease is well described, human cases rarely exceed 100-200 a year.

Australia has long been considered tularemia-free. So, it was surprising when, in 2011, two human cases were reported in Tasmania after exposure to ringtail possums.

While diagnostic tests on the patients’ samples suggested an infection with the bacterium, no samples were obtained from the offending possums to corroborate the unusual infection.

More importantly, researchers couldn’t grow and isolate the bacteria from any of the patients’ samples. Follow-up surveys of native animals in the area failed to detect the organism. So, the story of tularemia in Australia had, until recently, remained somewhat of a mystery.

How can I protect myself?

While our study has confirmed the presence of tularemia in Australia and identified ringtail possums as a reservoir for the disease, no-one knows if it’s present in other wildlife along the east coast.

Further reading: Bites and parasites: vector-borne diseases and the bugs spreading them

So, to minimise the chances of infection, take care when handling sick, distressed or dead animals. Similarly, when travelling in an area with ticks or other biting insects, wear protective clothing and repellents.

How do I know if I’m infected?

In humans, tularaemia symptoms can vary but typically depend on how someone was exposed.

An ulcer forms at the site of infection, like this one on someone’s hand.
CDC Public Health Image Library/Wikimedia

The most common form of disease in humans is known as ulceroglandular tularemia, which develops after an infected animal or insect bites or wounds you. As the name suggests, you develop a sudden fever, an ulcer forms at the site of infection, and the lymph glands near the wound swell.

Another and perhaps more serious form of the disease is pneumonic tularemia. This can occur when you breathe in bacteria from contaminated dust or aerosols, and your lungs become infected. Symptoms include cough, chest pain and difficulty breathing, and can be difficult to treat.

Yes, it can be treated

While infection can potentially cause severe disease and can kill, timely treatment with commonly available antibiotics should clear the infection. However, it is important the disease is correctly diagnosed as the most effective antibiotics (such as streptomycin) are often different to those used to treat other bacterial skin or wound infections.

There have been no reported cases of humans infecting other humans. While being exposed to someone infected with tularemia might pose some risk, the rarity of the cases and the effectiveness of antibiotic treatments to control the infection minimise this.

Looking to the future

What our study highlights more than anything is the need to investigate wildlife disease to understand potential risks to our environment and our own health.

So, we plan to conduct further surveys of animal and tick-borne diseases to explore undiscovered pathogens that may affect public health or impact our native animal populations.

We are also applying the same technology used to confirm the presence of tularemia in Australian wildlife for the first time to investigate other cold cases of the animal disease world – neglected and undiagnosed animal diseases.

We do this using a powerful technique called “RNA-Seq”, short for RNA sequencing, to analyse samples. With RNA-Seq, there’s no need to know what diseases might be present; researchers sequence all the genetic material in the sample, whether it has come from a host such as a human or animal, or from an infecting organism such as a virus, bacteria, or parasite.

This “metagenome” data is then pieced together and compared to databases containing genome data from previously sequenced pathogens.

The ConversationThrough these studies, we hope to reveal the full diversity of pathogens present in our native wildlife, and particularly, those that sit at the human-animal interface, a fault line that allows microbes to flow from one host to another. Most novel emerging diseases are spill-overs from zoonotic sources, so this research is critical for human health.

John-Sebastian Eden, NHMRC early career fellow, Faculty of Science, University of Sydney

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

Climate Council: climate, health and economics are against Carmichael mine

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Many banks are worried that coal investments could be left stranded on their asset books.

Will Steffen, Australian National University and Hilary Bambrick, Queensland University of Technology

Despite the overwhelming evidence that fossil fuels are killing the Great Barrier Reef and making many extreme weather events worse; despite the emphatic thumbs-down from the finance sector; and despite the growing awareness of the serious health impacts of coal, the proposed Carmichael coal mine staggers on, zombie-like, amid reports it has been offered a deferment of A$320 million in royalty payments. The Conversation

A new Climate Council report, Risky Business: Health, Climate and Economic Risks of the Carmichael Coalmine, makes an emphatic case against development of the proposed mine, or of any other coal deposits in Queensland’s Galilee Basin, or indeed elsewhere around the world.

Burning coal is a major contributor to climate change. Australia is already reeling from the escalating impacts of a warming climate. Heatwaves and other extreme weather events are worsening. The Great Barrier Reef has suffered consecutive mass bleaching events in 2016 and 2017. Climate change is likely making drought conditions worse in the agricultural belts of southwest and southeast Australia. Our coastal regions are increasingly exposed to erosion and flooding as sea level rises.

If we are to slow these disturbing trends and stabilise the climate at a level with which we might be able to cope, only a relatively small amount of the world’s remaining coal, oil and gas reserves can actually be used.

The majority must be left unburned in the ground, without developing vast new coal deposits such as those in the Galilee Basin.

On budget

The amount of fossil fuels we can burn for a given temperature target (such as the 1.5℃ and 2℃ targets of the Paris climate agreement) is known as the “carbon budget”.

To give ourselves just a 50% chance of staying within the 2℃ Paris target, we can burn only 38% of the world’s existing fossil fuel reserves. When this budget is apportioned among the various types of fossil fuels, coal is the big loser, because it is more emissions-intensive than other fuels. Nearly 90% of the world’s existing coal reserves must be left in the ground to stay within the 2℃ budget.

When the carbon budget is apportioned by region to maximise the economic benefit of the remaining budget, Australian coal in particular is a big loser. More than 95% of Australia’s existing coal reserves cannot be burned, and the development of new deposits, such as the Galilee Basin, is ruled out.

The health case

Exploiting coal is very harmful to human health, with serious impacts all the way through the process from mining to combustion. Recently the life-threatening “black lung” (coal workers’ pneumoconiosis) has re-emerged in Queensland, with 21 reported cases. Across Australia, the estimated costs of health damages associated with the combustion of coal amount to A$2.6 billion per year.

In India, the country to which coal from the proposed Carmichael mine would likely be exported, coal combustion already takes a heavy toll. An estimated 80,000-115,000 deaths, as well as 20 million cases of asthma, were attributed to pollutants emitted from coal-fired power stations in 2010-11. Up to 10,000 children under the age of five died because of coal pollution in 2012 alone.

Compared with the domestic coal resources in India, Carmichael coal will not reduce these health risks much at all. Galilee Basin coal is of poorer quality than that from other regions of Australia. Its estimated ash content of about 26% is double the Australian benchmark.

This is bad news for children in India or in any other country that ends up burning it.

The economics

The economic case for the Carmichael mine doesn’t stack up either. Converging global trends all point to rapidly reducing demand for coal.

The cost of renewable energy is plummeting, and efficient and increasingly affordable storage technologies are emerging. Coal demand in China is dropping as it ramps up the rollout of renewables. India is moving towards energy independence, and is eyeing its northern neighbour’s push towards renewables.

All of these trends greatly increase the risk that any new coal developments will become stranded assets. It’s little wonder that the financial sector has turned a cold shoulder to the Carmichael mine, and Galilee Basin coal development in general. Some 17 banks worldwide, including the “big four” in Australia, have ruled out any investment in the Carmichael mine.

From any perspective – climate, health, economy – the proposed mine is hard to justify. And yet the project keeps on keeping on.

Will Steffen, Emeritus professor, Fenner School of Environment and Society, Australian National University and Hilary Bambrick, Head of School, School of Public Health and Social Work, Queensland University of Technology

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