Just because both sides support drought relief, doesn’t mean it’s right


Lin Crase, University of South Australia

The bipartisan parliamentary vote to transform the A$3.9 billion Building Australia Fund into a pot of cash to drought-proof Australia, the Future Drought Fund, should not be taken as universal endorsement.

Labor opposed the idea before caving in, saying it did not “want to be painted as a party that opposes support for farmers”.

Rather, it simply shows that Australian politicians coalesce on some things: few miss the opportunity to be photographed with an affectionate child, and even fewer are willing to be critical of public funds being handed to drought-stricken farmers.

But support something (or feeling too scared not to oppose something), doesn’t necessarily make it the right policy.




Read more:
Drought is inevitable, Mr Joyce


Australian governments have sought to drought-proof parts of inland Australia through publicly funded irrigation schemes for much of the past century.

Whenever dryland farmers experienced drought, they were viewed as having experienced a natural disaster, even though the variability of dryland rains was well understood.

Then, from the 1960s, things changed.

First there was a growing realisation that public monies spent on irrigation were not the best means of dealing with a variable climate.

We’ve moved away from thinking about drought as disaster

Second, governments started to describe drought differently, culminating in a 1992 National Drought Policy that required farmers to be more self-reliant and absorb the impacts of drought as something to be expected.

The decades that followed continued this trend with all states and the Commonwealth agreeing on national principles in 2013. Concessional loans and a farm management deposit scheme with taxation advantages were available to help farmers, but would only be useful to those that were viable in the long term.

A Farm Household Allowance, set at the level of Newstart and available for up to four years in return for setting out a plan to improve the farmer’s financial circumstances, was also introduced in 2015 and refined in 2018.

Part of the thinking was that climate change is expected to make droughts more common and severe, although there are good reasons for encouraging adaptation to the existing climate in any case.




Read more:
Helping farmers in distress doesn’t help them be the best: the drought relief dilemma


However, getting the balance right between “supporting” farm businesses and encouraging them to adapt and be self-reliant isn’t straightforward, especially when the climate and political cycles coincide.

It’s hard to imagine politicians being fiscally prudent when they know they have access to a drought slush fund and are heading into an election during a drying phase.

So, what’s wrong with the new drought fund?

First, there is mounting evidence that farm businesses can actually benefit from drought in the longer term. This seems to occur because businesses that go through a drought develop coping strategies that when invoked in good years produce much greater profits.

That is not to say that droughts are financially a good thing – but it does mean that shielding farm businesses from drought runs the risk that they will not adapt.

Second, an obsession with drought undoes much of the good work done in reclassifying it as something to be expected rather than a natural disaster. Nearly all of the natural disaster payments made in the decade leading up to 2012-13 – one of the driest on record – were spent on rebuilding after floods and storms rather than droughts.

Third, while repurposing the Building Australia Fund as the Future Drought Fund is designed to appeal to rural and regional voters, it is unlikely to help them. Agriculture simply does not generate the jobs that it once did and public pronouncements about drought-proofing will not change the underlying economics of farm businesses and regional communities.




Read more:
Droughts, extreme weather and empowered consumers mean tough choices for farmers


Farming is generally helped by scale, and that means bigger farms with bigger machines displacing smaller farms. The upshot is fewer jobs and the shutdown of small towns, allowing only the larger regional centres to survive. Finding ways to manage this social phenomenon should be the priority rather than shielding farms from drought.

But it’s hard to be optimistic. Politicians love handing cheques to farmers as much as they love photographs with adoring children.The Conversation

Lin Crase, Professor of Economics and Head of School, University of South Australia

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

This is why nuking a hurricane will not work, Mr Trump


Liz Ritchie-Tyo, UNSW

President Donald Trump has reportedly suggested on more than one occasion that the US military explode nuclear bombs inside hurricanes to disrupt them before they reach land.

As reported in National Geographic, this is not the first time a suggestion like this has been made – although Trump now denies having said it.

On the surface, it would seem like a simple solution to the devastation that occurs in the US each year during the hurricane season. However, there are several problems with this idea.




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The economic cost of devastating hurricanes and other extreme weather events is even worse than we thought


What is a hurricane?

Hurricanes are low-pressure weather systems covering an area of more than 500,000km². They form over warm tropical oceans, which are their primary energy source. The low pressure at the centre of the hurricane – the eye – draws in the surrounding warm, moist air. This air then rises and condenses into deep thunderstorm clouds surrounding the centre – the eyewall – and also in cloud bands spiralling out from the eye called rainbands.

As the air is pulled into the eye, Earth’s rotation causes it to spin cyclonically – anticlockwise in the northern hemisphere and clockwise in the southern hemisphere. The continuous supply of air into the deep thunderstorms surrounding the eye allows the hurricane to intensify until it reaches a steady state of equilibrium with the oceans and the environment.

Would a nuclear bomb put a dent in a hurricane?

The average hurricane can be likened to a very inefficient heat engine. As the warm moist air rises, it releases heat energy through the formation of clouds and rain at a rate of about 5.2 x 10¹⁹ joules per day. Less than 10% of this heat is then converted into the mechanical energy of the wind.

To give some perspective of this energy, the heat released in a hurricane is equivalent to a 10-megatonne nuclear bomb exploding every hour. This energy is also on the order of the global energy consumption in 2016, according to the United States Energy Information Agency.

It seems unlikely that exploding a bomb in the hurricane would make much impact on such a powerful weather system, and it is impossible to run controlled experiments to determine whether it would.

Not to mention that there could be shocking effects from the fallout of radioactive material from such an explosion. These materials would be transported widely via the trade winds through the lower levels of the atmosphere, and potentially around the entire planet in the stratosphere – similar to the effects from the volcanic fallout from Mount Pinatubo in the Philippines in 1991.

Have people tried to stop hurricanes before?

There have been previous attempts to modify the impacts of hurricanes. Between 1962 and 1983 the US government funded experimental research on hurricane modification known as Project STORMFURY. The fundamental premise was, because the potential of damage from hurricanes increases rapidly with the hurricane’s wind speed, a reduction in wind speed of as little as 10% could make a large difference in the impacts when hurricanes reach land. By seeding the air outside the eyewall with silver iodide, a chemical used to seed clouds, it was thought a new ring of thunderstorms may develop outside the eyewall – robbing it of energy and weakening the hurricane.




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Getting ready for hurricane season: 4 essential reads


Modification was attempted in four hurricanes on eight different days. On four of those days, a 10-30% reduction in wind speed was measured. The lack of response on the other fours days was initially interpreted to be the result of faulty execution of the experiment, but was later attributed to an imperfect understanding of the microphysics of clouds in hurricanes.

Successful cloud seeding using silver iodide requires that supercooled water droplets freeze onto the silver iodide seeds.

Recent observations show hurricanes have too many naturally occurring ice crystals and too few supercooled water droplets for cloud seeding to be effective. So any change in hurricane wind speed observed during the STORMFURY experiments was almost certainly due to the natural behaviour of hurricanes rather than human intervention.

Although Project STORMFURY was abandoned, the hurricane observation program is still run under the Hurricane Research Division of the National Oceanic and Atmospheric Administration (NOAA). The original aircraft used in Project STORMFURY were replaced in the 1970s by WP-3D aircraft, which still reside under NOAA and are operated by its officers.




Read more:
Hurricanes to deliver a bigger punch to coasts


The observations collected by these aircraft continuously over a period of more than 60 years has helped improve hurricane forecasting. Furthermore, these observations have allowed researchers to develop vital insights into the structure, intensity, and physical processes of this most destructive of natural phenomena.The Conversation

Liz Ritchie-Tyo, Associate Professor, School of Physical, Environmental, and Mathematical Sciences, UNSW

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

Online tools can help people in disasters, but do they represent everyone?



Social media helped some people cope with the Townsville floods earlier this year.
AAP Image/Andrew Rankin

Billy Tusker Haworth, University of Manchester; Christine Eriksen, University of Wollongong, and Scott McKinnon, University of Wollongong

With natural hazard and climate-related disasters on the rise, online tools such as crowdsourced mapping and social media can help people understand and respond to a crisis. They enable people to share their location and contribute information.

But are these tools useful for everyone, or are some people marginalised? It is vital these tools include information provided from all sections of a community at risk.

Current evidence suggests that is not always the case.




Read more:
‘Natural disasters’ and people on the margins – the hidden story


Online tools let people help in disasters

Social media played an important role in coordinating response to the 2019 Queensland floods and the 2013 Tasmania bushfires. Community members used Facebook to coordinate sharing of resources such as food and water.

Crowdsourced mapping helped in response to the humanitarian crisis after the 2010 Haiti earthquake. Some of the most useful information came from public contributions.

Twitter provided similar critical insights during Hurricane Irma in South Florida in 2017.

Research shows these public contributions can help in disaster risk reduction, but they also have limitations.

In the rush to develop new disaster mitigation tools, it is important to consider whether they will help or harm the people most vulnerable in a disaster.

Who is vulnerable?

Extreme natural events, such as earthquakes and bushfires, are not considered disasters until vulnerable people are exposed to the hazard.




Read more:
Understanding the root causes of natural disasters


To determine people’s level of vulnerability we need to know:

  1. the level of individual and community exposure to a physical threat
  2. their access to resources that affect their capacity to cope when threats materialise.

Some groups in society will be more vulnerable to disaster than others. This includes people with immobility issues, caring roles, or limited access to resources such as money, information or support networks.

When disaster strikes, the pressure on some groups is often magnified.

The devastating scenes in New Orleans after Hurricane Katrina in 2005 and in Puerto Rico after Hurricane Maria in 2017 revealed the vulnerability of children in such disasters.

Unfortunately, emergency management can exacerbate the vulnerability of marginalised groups. For example, a US study last year showed that in the years after disasters, wealth increased for white people and declined for people of colour. The authors suggest this is linked to inequitable distribution of emergency and redevelopment aid.

Policies and practice have until recently mainly been written by, and for, the most predominant groups in our society, especially heterosexual white men.

Research shows how this can create gender inequities or exclude the needs of LGBTIQ communities, former refugees and migrants or domestic violence victims.




Read more:
More men die in bushfires: how gender affects how we plan and respond


We need to ask: do new forms of disaster response help everyone in a community, or do they reproduce existing power imbalances?

Unequal access to digital technologies

Research has assessed the “techno-optimism” – a belief that technologies will solve our problems – associated with people using online tools to share information for disaster management.

These technologies inherently discriminate if access to them discriminates.

In Australia, the digital divide remains largely unchanged in recent years. In 2016-17 nearly 1.3 million households had no internet connection.

Lower digital inclusion is seen in already vulnerable groups, including the unemployed, migrants and the elderly.

Global internet penetration rates show uneven access between economically poorer parts of the world, such as Africa and Asia, and wealthier Western regions.

Representations of communities are skewed on the internet. Particular groups participate with varying degrees on social media and in crowdsourcing activities. For example, some ethnic minorities have poorer internet access than other groups even in the same country.

For crowdsourced mapping on platforms such as OpenStreetMap, studies find participation biases relating to gender. Men map far more than women at local and global scales.

Research shows participation biases in community mapping activities towards older, more affluent men.

Protect the vulnerable

Persecuted minorities, including LGBTIQ communities and religious minorities, are often more vulnerable in disasters. Digital technologies, which expose people’s identities and fail to protect privacy, might increase that vulnerability.

Unequal participation means those who can participate may become further empowered, with more access to information and resources. As a result, gaps between privileged and marginalised people grow wider.

For example, local Kreyòl-speaking Haitians from poorer neighbourhoods contributed information via SMS for use on crowdsourced maps during the 2010 Haiti earthquake response.

But the information was translated and mapped in English for Western humanitarians. As they didn’t speak English, vulnerable Haitians were further marginalised by being unable to directly use and benefit from maps resulting from their own contributions.

Participation patterns in mapping do not reflect the true makeup of our diverse societies. But they do reflect where power lies – usually with dominant groups.

Any power imbalances that come from unequal online participation are pertinent to disaster risk reduction. They can amplify community tensions, social divides and marginalisation, and exacerbate vulnerability and risk.

With greater access to the benefits of online tools, and improved representation of diverse and marginalised people, we can better understand societies and reduce disaster impacts.

We must remain acutely aware of digital divides and participation biases. We must continually consider how these technologies can better include, value and elevate marginalised groups.The Conversation

Billy Tusker Haworth, Lecturer in GIS and Disaster Management, University of Manchester; Christine Eriksen, Senior Lecturer in Geography and Sustainable Communities, University of Wollongong, and Scott McKinnon, Vice-Chancellor’s Postdoctoral Research Fellow, University of Wollongong

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

After the floods come the mosquitoes – but the disease risk is more difficult to predict


Cameron Webb, University of Sydney

We’re often warned to avoid mosquito bites after major flooding events. With more water around, there are likely to be more mosquitoes.

As flood waters recede around Townsville and clean-up efforts continue, the local population will be faced with this prospect over the coming weeks.

But whether a greater number of mosquitoes is likely to lead to an outbreak of mosquito-borne disease is tricky to predict. It depends on a number of factors, including the fate of other wildlife following a disaster of this kind.

Mozzies need water

Mosquitoes lay their eggs in and around water bodies. In the initial stages, baby mosquitoes (or “wrigglers”) need the water to complete their development. During the warmer months, it doesn’t take much longer than a week before they are grown and fly off looking for blood.

So the more water, the more mosquito eggs are laid, and the more mosquitoes end up buzzing about.

But outbreaks of disease carried by mosquitoes are dependent on more than just their presence. Mosquitoes rarely emerge from wetlands infected with pathogens. They typically need to pick them up from biting local wildlife, such as birds or mammals, before they can spread disease to people.




Read more:
The worst year for mosquitoes ever? Here’s how we find out


Mosquitoes and extreme weather events

Historically, major inland flooding events have triggered significant outbreaks of mosquito-borne disease in Australia. These outbreaks have included epidemics of the potentially fatal Murray Valley encephalitis virus. In recent decades, Ross River virus has more commonly been the culprit.

A focal point of the current floods is the Ross River, which runs through Townsville. The Ross River virus was first identified from mosquitoes collected along this waterway. The disease it causes, known as Ross River fever, is diagnosed in around 5,000 Australians every year. The disease isn’t fatal but it can be seriously debilitating.

Following substantial rainfall, mosquito populations can dramatically increase. Carbon dioxide baited light traps are used by local authorities to monitor changes in mosquito populations.
Cameron Webb (NSW Health Pathology)

In recent years, major outbreaks of Ross River virus have occurred throughout the country. Above average rainfall is likely a driving factor as it boosts both the abundance and diversity of local mosquitoes.

Flooding across Victoria over the 2016-2017 summer produced exceptional increases in mosquitoes and resulted in the state’s largest outbreak of Ross River virus. There were almost 1,700 cases of Ross River virus disease reported there in 2017 compared to an average of around 300 cases annually over the previous 20 years.




Read more:
Explainer: what is Ross River virus?


Despite plagues of mosquitoes taking advantage of flood waters, outbreaks of disease don’t always follow.

Flooding resulting from hurricanes in North America has been associated with increased mosquito populations. After Hurricane Katrina hit Louisiana and Mississippi in 2005, there was no evidence of increased mosquito-borne disease. The impact of wind and rain is likely to have adversely impacted local mosquitoes and wildlife, subsequently reducing disease outbreak risk.

Applying insect repellent is worthwhile even if the risk of mosquito-borne disease isn’t known.
From shutterstock.com

Australian studies suggest there’s not always an association between flooding and Ross River virus outbreaks. Outbreaks can be triggered by flooding, but this is not always the case. Where and when the flooding occurs probably plays a major role in determining the likelihood of an outbreak.

The difficulty in predicting outbreaks of Ross River virus disease is that there can be complex biological, environmental and climatic drivers at work. Conditions may be conducive for large mosquito populations, but if the extreme weather events have displaced (or decimated) local wildlife populations, there may be a decreased chance of outbreak.

This may be why historically significant outbreaks of mosquito-borne disease have occurred in inland regions. Water can persist in these regions for longer than coastal areas. This provides opportunities not only for multiple mosquito generations, but also for increasing populations of water birds. These birds can be important carriers of pathogens such as the Murray Valley encephalitis virus.




Read more:
Giant mosquitoes flourish in floodwaters that hurricanes leave behind


In coastal regions like Townsville, where the main concern would be Ross River virus, flood waters may displace the wildlife that carry the virus, such as kangaroos and wallabies. For that reason, the flood waters may actually reduce the initial risk of outbreak.

Protect yourself

There is still much to learn about the ecology of wildlife and their role in driving outbreaks of disease. And with a fear of more frequent and severe extreme weather events in the future, it’s an important area of research.

Although it remains difficult to predict the likelihood of a disease outbreak, there are steps that can be taken to avoid mosquito bites. This will be useful even if just to reduce the nuisance of sustaining bites.

Cover up with long-sleeved shirts and long pants for a physical barrier against mosquito bites and use topical insect repellents containing DEET, picaridin, or oil of lemon eucalyptus. Be sure to apply an even coat on all exposed areas of skin for the longest lasting protection.The Conversation

Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of Sydney

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

Here’s what you need to know about melioidosis, the deadly infection that can spread after floods



File 20190214 1721 1pkznl1.jpg?ixlib=rb 1.1
People typically become sick between one and 21 days after being infected.
Goran Jakus/Shutterstock

Sanjaya Senanayake, Australian National University

The devastating Townsville floods have receded but the clean up is being complicated by the appearance of a serious bacterial infection known as melioidosis. One person has died from melioidosis and nine others have been diagnosed with the disease over the past week.

The bacteria that causes the disease, Burkholderia pseudomallei, is a hardy bug that lives around 30cm deep in clay soil. Events that disturb the soil, such as heavy rains and floods, bring B. pseudomallei to the surface, where it can enter the body through through a small break in the skin (that a person may not even be aware of), or by other means.

Melioidosis may cause an ulcer at that site, and from there, spread to multiple sites in the body via the bloodstream. Alternatively, the bacterium can be inhaled, after which it travels to the lungs, and again may spread via the bloodstream. Less commonly, it’s ingested.




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(At least) five reasons you should wear gardening gloves


Melioidosis was first identified in the early 20th century among drug users in Myanmar. These days, cases tend to concentrate in Southeast Asia and the top end of northern Australia.

What are the symptoms?

Melioidosis can cause a variety of symptoms, but often presents as a non-specific flu-like illness with fever, headache, cough, shortness of breath, disorientation, and pain in the stomach, muscles or joints.

People with underlying conditions that impair their immune system – such as diabetes, chronic kidney or lung disease, and alcohol use disorder – are more likely to become sick from the infection.

The majority of healthy people infected by melioidosis won’t have any symptoms, but just because you’re healthy, doesn’t mean you’re immune: around 20% of people who become acutely ill with melioidosis have no identifiable risk factors.

People typically become sick between one and 21 days after being infected. But in a minority of cases, this incubation period can be much longer, with one case occurring after 62 years.

How does it make you sick?

While most people who are sick with melioidosis will have an acute illness, lasting a short time, a small number can have a grumbling infection persisting for months.

One of the most common manifestations of melioidosis is infection of the lungs (pneumonia), which can occur either via infection through the skin, or inhalation of B. pseudomallei.

The challenges in treating this organism, though, arise from its ability to form large pockets of pus (abscesses) in virtually any part of the body. Abscesses can be harder to treat with antibiotics alone and may also require drainage by a surgeon or radiologist.

How is it treated?

Thankfully, a number of antibiotics can kill B. pseudomallei. Those recovering from the infection will need to take antibiotics for at least three months to cure it completely.

If you think you might have melioidosis, seek medical attention immediately. A prompt clinical assessment will determine the level of care you need, and allow antibiotic therapy to be started in a timely manner.

Your blood and any obviously infected body fluids (sputum, pus, and so on) will also be tested for B. pseudomallei or other pathogens that may be causing the illness.

While cleaning up after these floods, make sure you wear gloves and boots to minimise the risk of infection through breaks in the skin. This especially applies to people at highest risk of developing melioidosis, namely those with diabetes, alcohol use disorder, chronic kidney disease, and lung disease.




Read more:
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The Conversation


Sanjaya Senanayake, Associate Professor of Medicine, Infectious Diseases Physician, Australian National University

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

Queensland’s floods are so huge the only way to track them is from space


Linlin Ge, UNSW

Many parts of Queensland have been declared disaster zones and thousands of residents evacuated due to a 1-in-100-year flood. Townsville is at the epicentre of the “unprecedented” monsoonal downpour that brought more than a year’s worth of rain in just a few days, and the emergency is far from over with yet more torrential rain expected.

Such monumental disruption calls for emergency work to safeguard crucial infrastructure such as bridges, dams, motorways, railways, power substations, power lines and telecommunications cables. In turn, that requires accurate, timely mapping of flood waters.

For the first time in Australia, our research team has been monitoring the floods closely using a new technique involving European satellites, which allows us to “see” beneath the cloud cover and map developments on the ground.




Read more:
Floods don’t occur randomly, so why do we still plan as if they do?


Given that the flooding currently covers a 700km stretch of coast from Cairns to Mackay, it would take days to piece together the big picture of the flood using airborne mapping. What’s more, conventional optical imaging satellites are easily “blinded” by cloud cover.

But a radar satellite can fly over the entire state in a matter of
seconds, and an accurate and comprehensive flood map can be produced in less than an hour.

Eyes above the skies

Our new method uses an imaging technology called “synthetic aperture radar” (SAR), which can observe the ground day or night, through cloud cover or smoke. By combining and comparing SAR images, we can determine the progress of an unfolding disaster such as a flood.

In simple terms, if an area is not flooded on the first image but is inundated on the second image, the resulting discrepancy between the two images can help to reveal the flood’s extent and identify the advancing flood front.

To automate this process and make it more accurate, we use two pairs of images: a “pre-event pair” taken before the flood, and a “co-event pair” made up of one image before the flood, and another later image during the flooding.

The European satellites have been operated strategically to collect images globally once every 12 days, making it possible for us to test this new technique in Townsville as soon as flooding occurs.

To monitor the current floods in Townsville, we took the pre-event images on January 6 and January 18, 2019. The co-event pair was collected on January 18 and January 30. These sets of images were then used to generate the accurate and detailed flood map shown below.

The image comparisons can all be done algorithmically, without a human having to scrutinise the images themselves. Then we can just look out for image pairs with significant discrepancies, and then concentrate our attention on those.

Satellite flood mapping along the Queensland coast, compiled using images from the European radar satellite Sentinel-1A.
European Space Agency/Smart Spatial Technology Development Laborator (SSTD), UNSW, Author provided



Read more:
Planning for a rainy day: there’s still lots to learn about Australia’s flood patterns


Our technique potentially avoids the need to monitor floods from airborne reconnaissance planes – a dangerous or even impossible task amid heavy rains, strong wind, thick cloud and lightning.

This timely flood intelligence from satellites can be used to switch off critical infrastructure such as power substations before flood water reaches them.The Conversation

Linlin Ge, Professor, UNSW

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

Sydney storms could be making the Queensland fires worse


Claire Yeo, Australian Bureau of Meteorology

A strong low-pressure system has meant severe thunderstorm and hail warnings are in effect for much of the New South Wales South Coast. At the same time, very dry conditions, strong winds and high temperatures are fuelling dozens of bushfires across Queensland.

The two events are actually influencing each other. As the low-pressure system moves over the Greater Sydney area, a connected wind change is pushing warm air (and stronger winds) to Queensland, worsening the fire conditions.




Read more:
Drought, wind and heat: when fire seasons start earlier and last longer


These lows over NSW are the kind we might see a couple of times a year – they’re not just regular weather systems, but neither are they massively out of the ordinary.

However, when combined with the current record-breaking heat in Queensland, the extra wind is creating exceptionally dangerous fire conditions. Queensland’s emergency services minister, Craig Crawford, has warned Queenslanders:

We are expecting a firestorm. We are expecting it to be so severe that it won’t even be safe on the beach […] The only thing to do is to go now.

Conditions in Queensland

At least 80 bushfires were burning in Queensland on Wednesday, with more than a dozen fire warnings issued to communities near the Deepwater blaze. Queensland Police Deputy Commissioner Bob Gee said that “people will burn to death” unless they evacuate the area.

These fires have come during a record-breaking heatwave. On Tuesday Cooktown recorded 43.9℃, beating the previous November high set 70 years ago by more than two degrees. Cairns has broken its November heatwave record by five whole degrees.

Grasslands and forests are very dry after very little rain over the past two years. Adding to these conditions are strong winds, which make the fires hotter, faster and harder to predict. This is where the storm conditions in NSW come in: they are affecting air movements across both states.

NSW low is driving winds over Queensland

A large low-pressure system, currently over the Hunter Valley area, is causing the NSW storms. As it moves, it’s pushing a mass of warm air ahead of it, bringing both higher temperatures and stronger winds across the Queensland border.

Once the low-pressure system moves across the Hunter area to the Tasman Sea east of Sydney, it will drag what we call a “wind change” across Queensland. This will increase wind speeds through Queensland and temperatures, making the fire situation even worse.

This is why emergency services are keeping watch for “fire tornado” conditions. When very hot air from large fires rises rapidly into a turbulent atmosphere, it can create fire storms – thunderstorms containing lightning or burning embers. Strong wind changes can also mean fire tornadoes form, sucking up burning material. Both of these events spread fires quickly and unpredictably.




Read more:
Turn and burn: the strange world of fire tornadoes


What does this mean for the drought

Unfortunately, it’s not likely the heavy rains over NSW will have a long-term effect on the drought gripping much of the state. While very heavy rains have fallen over 24 hours, the drought conditions have persisted for years.




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Trust Me, I’m An Expert: Australia’s extreme weather


The wet weather may bring some temporary relief, but NSW will need much more rain over a longer period to truly alleviate the drought.

In the meantime, the Bureau of Meteorology will be monitoring the Queensland situation closely. You can check weather warnings for your area on the bureau’s website.The Conversation

Claire Yeo, Supervising Meteorologist, Australian Bureau of Meteorology

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