You can leave water out for wildlife without attracting mosquitoes, if you take a few precautions



Leaving water out for wildlife is important during droughts and bushfires but if it’s not changed regularly it can be a breeding ground for mosquitoes.
Roger Smith/Flickr, CC BY-NC

Cameron Webb, University of Sydney

Australia is in for a long, hot summer. The recent bushfires have been devastating for communities and wildlife. Drought is also impacting many regions.

Understandably, people want to leave water out for thirsty birds and animals.

Health authorities generally warn against collecting and storing water in backyards as one measure to protect against mosquito bites and mosquito-borne diseases caused by, for example, dengue and Ross River viruses.




Read more:
How Australian wildlife spread and suppress Ross River virus


But it’s possible to leave water out for wildlife – and save water for your garden – without supplying a breeding ground for mosquitoes, if you take a few precautions.

For some mozzies, any water will do

Mosquitoes often look for wetlands and ponds to lay their eggs. But sometimes, anything that holds water – a bucket, bird bath, drain or rainwater tank – will do.

When the immature stages of mosquitoes hatch out of those eggs, they wriggle about in the water for a week or so before emerging to fly off in search of blood.

While there are many mosquitoes found in wetlands and bushland areas, Aedes notoscriptus and Culex quinquefasciatus are the mosquitoes most commonly found in our backyards and have been shown to transmit pathogens that cause mosquito-borne disease.

The Australian backyard mosquito (Aedes notoscriptus) is quick to take advantage of water-filled containers around the home.
Cameron Webb (NSW Health Pathology)

In central and north Queensland, mosquitoes such as Aedes aegypti can bring more serious health threats, such as dengue, to some towns.




Read more:
After decades away, dengue returns to central Queensland


Mosquitoes can also impact our quality of life through bites as well as the nuisance of simply buzzing about our bedrooms and backyards.

So how can you stop mozzies making a home in your backyard?

Empty water containers once a week

Mosquitoes need access to standing water for about a week or so. Reduce the number of water-filled containers available or how long that water is available to mosquitoes.

Emptying a water-filled container once a week will stop the immature mosquitoes from completing their development and emerging as adults.

If you’re leaving water out for pets or wildlife, use smaller volume containers that will allow for easy emptying once a week. You can tip any remaining water into the garden, as mosquito larvae won’t survive if they’re “stranded” on soil.

For larger or heavier items, such as bird baths, flushing them out once a week with the hose will knock out most of the wrigglers and stop the mosquitoes completing their life cycle.

Make sure garden water doesn’t slosh about

Be careful with self-watering planter boxes. These often have a reservoir of water in their base and, while it may seem like a water-wise idea, these can turn into tiny mozzie hotels!

A simple trick to keep water available to plants, but not mosquitoes, is to fill your potted plant saucers with sand. The sand traps and stores some moisture but there is no water sloshing about for mosquitoes.

If you’re collecting water from showers, baths, or washing machines (commonly known as grey water), use it immediately on the garden, don’t store it outside in buckets or other containers.




Read more:
How drought is affecting water supply in Australia’s capital cities


Gutters, ponds, tanks and pools

Make sure your roof gutters and drains are free of leaves and other debris that will trap water and provide opportunities for mosquitoes.

Ensure rainwater tanks (and other large water-storage containers) are appropriately screened to prevent access by mosquitoes.

Rainwater tanks can be a useful way to conserve water in our cities but they can also be a source of mosquitoes.
Cameron Webb (NSW Health Pathology)

A well maintained swimming pool won’t be a source of mosquitoes. But if it’s turning “green”, through neglect and not intent, it may become a problem. Mosquitoes don’t like the chlorine or salt treatments typically used for swimming pools but when there is a build up of leaves and other detritus, as well as algae, the mosquitoes will move in.




Read more:
As heat strikes, here’s one way to help fight disease-carrying and nuisance mosquitoes


For backyard ponds, introducing native fish can help keep mosquito numbers down.

But if you want your pond to be a home for frogs, avoid fish as they may eat the tadpoles. Instead, try to encourage other wildlife that may help keep mosquito numbers down by creating habitats for spiders and other predatory insects, reptiles, frogs, birds, and bats.

Avoiding excessive use of insecticides around the backyard will help encourage and protect that wildlife too.

Mozzies can still come

There isn’t much that can be done about those mosquitoes flying in from over the back fences from local bushland or wetland areas.

Mosquitoes are generally most active at dusk and dawn so keep that in mind when planning time outdoors. But when mosquito populations are peaking, they’ll be active almost all day long.

Applying an insect repellent can be a safe and effective way to stop those bites.




Read more:
The best (and worst) ways to beat mosquito bites


Covering up with long pants, long-sleeved shirt and shoes will provide a physical barrier to mosquitoes. If you’re spending a lot of time outdoors, perhaps even consider treating your clothing with insecticide to add that extra little bit of protection.

Make sure insect screens are installed, and in good condition, on windows and doors. Mosquitoes outdoors can be bad; you don’t want them inside as well.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.

Weather bureau says hottest, driest year on record led to extreme bushfire season



It’s the first time since overlapping records began that Australia experienced both its lowest rainfall and highest temperatures in the same year.
dan HIMBRECHTS/AAP

David Jones, Australian Bureau of Meteorology; Karl Braganza, Australian Bureau of Meteorology, and Skie Tobin, Australian Bureau of Meteorology

The Bureau of Meteorology’s annual climate statement released today confirms 2019 was the nation’s warmest and driest year on record. It’s the first time since overlapping records began that Australia experienced both its lowest rainfall and highest temperatures in the same year.

The national rainfall total was 37mm, or 11.7%, below the 314.5 mm recorded in the previous driest year in 1902. The national average temperature was nearly 0.2°C above the previous warmest year in 2013.

Globally, 2019 is likely to be the second-warmest year, with global temperatures about 0.8 °C above the 1961–1990 average. It has been the warmest year without the influence of El Niño.

Across the year, Australia experienced many extreme events including flooding in Queensland and large hail in New South Wales. However, due to prolonged heat and drought, the year began and ended with fires burning across the Australian landscape.




Read more:
‘This crisis has been unfolding for years’: 4 photos of Australia from space, before and after the bushfires


Part of Menindee Lakes on the Darling River, which is under pressure from low water flow as a result of the prolonged drought.
Dean Lewins/AAP

The effect of the long dry

Bushfire activity for the 2018–19 season began in late November 2018, when fires burned along a 600km stretch of the central Queensland coast. Widespread fires later followed across Victoria and Tasmania throughout the summer.

Persistent drought and record temperatures were a major driver of the fire activity, and the context for 2019 lies in the past three years of drought.

The dry conditions steadily worsened over 2019, resulting in Australia’s driest year on record, with area-average rainfall of just 277.6mm (the 1961–1990 average is 465.2 mm).



Almost the entire continent experienced rainfall in the lowest 10th percentile over the year.

Record low rainfall affected the central and southern inland regions of the continent and the north-eastern Murray–Darling Basin straddling the NSW and Queensland border. Many weather stations over central parts of Australia received less than 30mm of rainfall for the year.

Every capital city recorded below average annual rainfall. For the first time, national rainfall was below average in every month.



Record heat dominates the nation

2019 was Australia’s warmest year on record, with the annual mean temperature 1.52°C above the 1961–1990 average, surpassing the previous record of 1.33°C above average in 2013.

January, February, March, April, July, October, November, and December were all amongst the ten warmest on record for Australian mean temperature for their respective months, with January and December exceeding their previous records by 0.98°C and 1.08°C respectively.

Maximum temperatures recorded an even larger departure from average of +2.09°C for the year. This is the first time the nation has seen an anomaly of more than 2 °C, and about half a degree warmer than the previous record in 2013.



The year brought the nation’s six hottest days on record peaking at 41.9°C
(December 18), the hottest week 40.5 °C (week ending December 24), hottest month 38.6 °C (December 2019), and hottest season 36.9 °C (summer 2018–19).

The highest temperature for the year was 49.9 °C at Nullarbor (a new national December record) on December 19 and the coldest temperature was –12.0°C at Perisher Valley on June 20.

Keith West in southeast South Australia recorded a maximum 49.2°C on December 20, while Dover in far southern Tasmania saw 40.1°C on March 2, the furthest south such high temperatures have been observed in Australia.

Accumulating fire danger over 2019

The combination of prolonged record heat and drought led to record fire weather over large areas throughout the year, with destructive bushfires affecting all states, and multiple states at once in the final week of the year.

Many fires were difficult to contain in regions where drought has been severe, such as northern NSW and southeast Queensland, or where below average rainfall has been persistent, such as southeast Australia.

The Forest Fire Danger Index, a measure of fire weather severity, accumulated over the month of December was the highest on record for that month, and the highest for any month when averaged over the whole of Australia.



Record-high daily index values for December were recorded at the very end of December around Adelaide and the Yorke Peninsula in South Australia, East Gippsland in Victoria and the Monaro in NSW. These regions which experienced significant fire activity.

Don’t forget the floods

Amidst the dry, 2019 also included significant flooding across Queensland and the eastern Top End.

Heavy rain fell from January into early February, with damaging floods around Townsville and parts of the western Peninsula and Gulf Country.

Tropical cyclone Trevor brought further heavy rainfall in April in the eastern Northern Territory and Queensland. Floodwaters eventually reached Lake Eyre/Kati Thanda which, amidst severe local rainfall deficiencies in South Australia, experienced its most significant filling since 2010–11.

There was a notable absence of rainfall on Australia’s snow fields during winter and spring which meant less snow melt. Snow cover was generous, particularly at higher elevations.

A Townsville resident removes damaged items from a house after the Townsville floods in early 2019.
Dan Peled/AAP

What role did climate change play in 2019?

The climate each year reflects random variations in weather, slowly evolving natural climate drivers such as El Niño, and long-term trends through the influence of climate change.

A strong and long-lived positive Indian Ocean Dipole – another natural climate driver – affected Australia from May until the end of the year, and played a major role in suppressing rainfall and raising temperatures for much of the year.

Spring brought an unusual breakdown of the southern polar vortex which allowed westerly winds to affect mainland Australia. This reduced rainfall, raising temperature and contributing to the increased fire risk.

Climate change continues to cause long-term changes to Australia’s climate. Conditions in 2019 were consistent with trends of declining rainfall in parts of the south, worsening fire seasons and rising temperatures.




Read more:
Australia can expect far more fire catastrophes. A proper disaster plan is worth paying for


The Conversation


David Jones, Climate Scientist, Australian Bureau of Meteorology; Karl Braganza, Climate Scientist, Australian Bureau of Meteorology, and Skie Tobin, Climatologist, Australian Bureau of Meteorology

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

The bushfires are horrendous, but expect cyclones, floods and heatwaves too



Bushfires are not the only weather and climate events set to ravage Australia in coming months.
Dave Hunt/AAP

Neville Nicholls, Monash University

Public attention on the disastrous bushfire crisis in Australia will rightly continue for weeks to come. But as we direct resources to coping and recovery, we should not forget other weather and climate challenges looming this summer.

The peak time for heatwaves in southern Australia has not yet arrived. Many parts of Australia can expect heavy rains and flooding. And northern Australia’s cyclone season is just gearing up.

The events will stretch the ability of emergency services and the broader community to cope. The best way to prepare for these events is to keep an eye on Bureau of Meteorology forecasts.

Fires and other extreme events will test emergency services this summer.
Darren Pateman/AAP

Let it rain

2019 was Australia’s driest year on record. Since early winter the Bureau of Meteorology has correctly predicted the development of these widespread dry conditions.

But relief may be coming. The latest bureau outlooks suggest more normal summer conditions from February to April. If it eventuates, this would include more rain.




Read more:
How to monitor the bushfires raging across Australia


The arrival of drought-breaking rains is notoriously hard to predict – in the past, they have come any time between January and May. Global warming is also complicating seasonal climate predictions.

We all hope the rain arrives sooner rather than later, and eases the fire situation. But rain will bring other risks.

Continental-scale droughts such as that experienced over the past few years are often broken by widespread heavy rains, leading to an increased risk of flooding including potentially lethal flash floods. The decade-long Millenium drought that ended in 2009 was followed by two extremely wet years with serious flooding.

A similar situation was seen in Indonesia in recent days when very heavy rains after a prolonged drought produced disastrous floods and landslides.

Indonesian rescuers searching for missing people after a landslide in West Java, Indonesia, triggered by heavy rain.
EPA

The flood risk is exacerbated by the bare soil and lack of vegetation caused by drought, and by bushfires that destroy forest and grassland.

Australia’s north may be particularly hard hit. The onset of the tropical wet season has been very much delayed, as the bureau predicted. Over the last three months, some parts of the Australian tropics had their lowest ever October-December rainfall. But there are some suggestions widespread rain may be on its way.

Further south, drought-breaking rains can also be heavy and widespread, leading to increased flood risk. So even when the drought breaks and rains quell the fires, there will likely still be bouts of extreme weather, and high demand for emergency services.

Cyclones and heatwaves

The tropical cyclone season has been much delayed, as predicted by the bureau, although there are now signs of cyclonic activity in the near future.

Cyclones often bring welcome rains to drought-affected communities. But we should not overlook the serious damage these systems may bring such as coastal flooding and wind damage – again requiring intervention from emergency services.




Read more:
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And we are still a month away from the riskiest time for heatwaves in southern Australia. We’ve already had some severe heatwaves this summer. However they usually peak in the middle and end of summer, so the worst may be yet to come.

Lives have undoubtedly been saved this summer by improved forecasting of high temperatures and better dissemination of heatwave information by state and local governments. But after an already devastating early summer of fires and heat, warning fatigue may set in amongst both warning providers and the public. We must ensure heatwave warnings continue to be disseminated to populations at risk, and are acted on.

Shop staff clean up storm waters after Cyclone Debbie hit iQueensland in 2017.
AAP

Be thankful for weather forecasters

The recent experience of farmers, fire fighters, water resource managers and communities illustrate the value of the service provided by the Bureau of Meteorology. Greatly improved weather and climate forecasting developed over the past few decades means communities can plan for and deal with our highly variable weather and climate far better than in the past.




Read more:
It’s only October, so what’s with all these bushfires? New research explains it


Recent drought, fires and heatwaves – exacerbated by global warming – have been devastating. But imagine if we only had the limited weather forecast capabilities of even a few decades ago, without today’s high-speed computers to run weather forecast models, and satellites to feed in enormous amounts of data. How much worse would the impacts have been?

These forecasts have allowed heat alerts to be disseminated to vulnerable communities. Detailed information on weather conducive to fire spread has helped fire agencies provide more targeted warnings and direct resources appropriately.

An air tanker makes a pass to drop fire retardant on a bushfire in North Nowra, NSW, as fires spread rapidly.
Mick Tsikas/AAP

Never before have weather forecasts been so readily available to the public. Here are ways you can use them to reduce risks to life and property during an extreme event:

  • Listen to ABC local radio for emergency updates and detailed Bureau of Meteorology forecasts
  • load your state fire service emergency app onto your phone and check it regularly. Or check out the information online, such as at the NSW Rural Fire Service’s Fires Near Me website
  • check the bureau’s website for climate and weather forecasts
  • download a short-range rainfall forecast app such as Rain Parrot onto your phone. These apps use the bureau’s radar data to make short-range forecasts of rainfall for your location, and notify you if rain is coming.

Global warming is already lengthening the fire season and making heatwaves more intense, more frequent, and longer. It is also increasing the likelihood of heavy rains, and making droughts worse.

We must keep adapting to these changing threats, and further improve our ability to forecast them. And the community must stay aware of the many weather and climate extremes that threaten lives and property.The Conversation

Neville Nicholls, Professor emeritus, School of Earth, Atmosphere and Environment, Monash University

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

Firestorms and flaming tornadoes: how bushfires create their own ferocious weather systems



A firestorm on Mirror Plateaun Yellowstone Park, 1988.
Jim Peaco/US National Park Service

Rachel Badlan, UNSW

As the east coast bushfire crisis unfolds, New South Wales Premier Gladys Berejiklian and Rural Fire Service operational officer Brett Taylor have each warned residents bushfires can create their own weather systems.

This is not just a figure of speech or a general warning about the unpredictability of intense fires. Bushfires genuinely can create their own weather systems: a phenomenon known variously as firestorms, pyroclouds or, in meteorology-speak, pyrocumulonimbus.




Read more:
Firestorms: the bushfire/thunderstorm hybrids we urgently need to understand


The occurrence of firestorms is increasing in Australia; there have been more than 50 in the period 2001-18. During a six-week period earlier this year, 18 confirmed pyrocumulonimbus formed, mainly over the Victorian High Country.

A pyrocumulonimbus cloud generated by a bushfire in Licola,Victoria, on March 2, 2019.
Elliot Leventhal, Author provided

Its not clear whether the current bushfires will spawn any firestorms. But with the frequency of extreme fires set to increase due to hotter and drier conditions, it’s worth taking a closer look at how firestorms happen, and what effects they produce.

What is a firestorm?

The term “firestorm” is a contraction of “fire thunderstorm”. In simple terms, they are thunderstorms generated by the heat from a bushfire.

In stark contrast to typical bushfires, which are relatively easy to predict and are driven by the prevailing wind, firestorms tend to form above unusually large and intense fires.

If a fire encompasses a large enough area (called “deep flaming”), the upward movement of hot air can cause the fire to interact with the atmosphere above it, potentially forming a pyrocloud. This consists of smoke and ash in the smoke plume, and water vapour in the cloud above.

If the conditions are not too severe, the fire may produce a cloud called a pyrocumulus, which is simply a cloud that forms over the fire. These are typically benign and do not affect conditions on the ground.

But if the fire is particularly large or intense, or if the atmosphere above it is unstable, this process can give birth to a pyrocumulonimbus – and that is an entirely more malevolent beast.

What effects do firestorms produce?

A pyrocumulonibus cloud is much like a normal thunderstorm that forms on a hot summer’s day. The crucial difference here is that this upward movement is caused by the heat from the fire, rather than simply heat radiating from the ground.

Conventional thunderclouds and pyrocumulonimbus share similar characteristics. Both form an anvil-shaped cloud that extends high into the troposphere (the lower 10-15km of the atmosphere) and may even reach into the stratosphere beyond.

NASA image of pyrocumulonimbus formation in Argentina, January 2018.
NASA

The weather underneath these clouds can be fierce. As the cloud forms, the circulating air creates strong winds with dangerous, erratic “downbursts” – vertical blasts of air that hit the ground and scatter in all directions.

In the case of a pyrocumulonimbus, these downbursts have the added effect of bringing dry air down to the surface beneath the fire. The swirling winds can also carry embers over huge distances. Ember attack has been identified as the main cause of property loss in bushfires, and the unpredictable downbursts make it impossible to determine which direction the wind will blow across the ground. The wind direction may suddenly change, catching people off guard.

Firestorms also produce dry lightning, potentially sparking new fires, which may then merge or coalesce into a larger flaming zone.

In rare cases, a firestorm can even morph into a “fire tornado”. This is formed from the rotating winds in the convective column of a pyrocumulonimbus. They are attached to the firestorm and can therefore lift off the ground.




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


This happened during the infamous January 2003 Canberra bushfires, when a pyrotornado tore a path near Mount Arawang in the suburb of Kambah.

A fire tornado in Kambah, Canberra, 2003 (contains strong language).

Understandably, firestorms are the most dangerous and unpredictable manifestations of a bushfire, and are impossible to suppress or control. As such, it is vital to evacuate these areas early, to avoid sending fire personnel into extremely dangerous areas.

The challenge is to identify the triggers that cause fires to develop into firestorms. Our research at UNSW, in collaboration with fire agencies, has made considerable progress in identifying these factors. They include “eruptive fire behaviour”, where instead of a steady rate of fire spread, once a fire interacts with a slope, the plume may attach to the ground and rapidly accelerate up the hill.

Another process, called “vorticity-driven lateral spread”, has also been recognised as a good indicator of potential fire blow-up. This occurs when a fire spreads laterally along a ridge line instead of following the direction of the wind.

Although further refinement is still needed, this kind of knowledge could greatly improve decision-making processes on when and where to deploy on-ground fire crews, and when to evacuate before the situation turns deadly.The Conversation

Rachel Badlan, Postdoctoral Researcher, Atmospheric Dynamics, UNSW

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

The science of drought is complex but the message on climate change is clear



Detecting human fingerprints on complex events like droughts is not straightforward.
AAP Image/Dan Peled

Ben Henley, University of Melbourne; Andrew King, University of Melbourne; Anna Ukkola, Australian National University; Murray Peel, University of Melbourne; Q J Wang, University of Melbourne, and Rory Nathan, University of Melbourne

The issue of whether Australia’s current drought is caused by climate change has been seized on by some media commentators, with debate raging over a remark from eminent scientist Andy Pitman that “there is no link between climate change and drought”. Professor Pitman has since qualified, he meant to say “there is no direct link between climate change and drought”.

A highly politicised debate that tries to corner scientists will not do much to help rural communities struggling with the ongoing dry. But it is still worthwhile understanding the complexity of how climate change relates to drought.




Read more:
Is Australia’s current drought caused by climate change? It’s complicated


So, why the contention?

It may seem like splitting hairs to focus on single words, but the reality is drought is complex, and broad definitive statements are difficult to make. Nevertheless, aspects of drought are linked with climate change. Let us try to give you a taste of the complexity.

First, it’s important to understand that drought is a manifestation of interactions between the atmosphere, ocean, and land. In Australia, the Bureau of Meteorology uses rainfall deficiencies to identify regions that are under drought conditions. Anyone on the land doesn’t need to be reminded, but the current drought is seriously bad. These maps show the patterns of rainfall deficiency over the past 36 and 18 months, highlighting the severity and extent of what we call meteorological drought.

Widespread rainfall deficiencies over the last 36 months (left) and 18 months (right)
Australian Bureau of Meteorology

But along with the main driver – low rainfall – droughts can also be exacerbated by water loss through evaporation. This depends not only on temperature but also humidity, wind speeds, and sunshine. Temperature will clearly continue to rise steadily almost everywhere. For the other factors, the future is not quite as clear.

Water loss also varies according to vegetation cover. Plants respond to higher carbon dioxide levels and drought by closing the tiny holes in their leaves (the stomata) and this can actually reduce water loss in wet environments. However, in water-stressed environments, projected long-term declines in rain may be compounded by plants using more water, further reducing streamflow. Actually, we can glean a lot from studying hydrological drought, which is measured by a period of low flow in rivers.

The point here is droughts are multidimensional, and can affect water supply on a wide range of spatial and temporal scales. A seasonal-scale drought that reduces soil moisture on a farm, and a decade-long drought that depletes reservoirs and groundwater supplies, can each be devastating, but in different ways.

Is climate change affecting Australian droughts?

Climate change may affect drought metrics and types of drought differently, so it can be hard to make general statements about the links between human-induced climate change and all types of drought, in all locations, on all timescales.

Southern Australia, and in particular the southwest, has seen a rapid decline in winter rainfall and runoff that has been linked to climate change. In the southeast there has also been a substantial decline in winter rainfall and total runoff in recent decades. Although the reductions are consistent with climate change projections, the trend so far is harder to distinguish from the year-to-year variability.

There is some evidence to suggest that widespread and prolonged droughts, like the Millennium Drought, are worse than other droughts in past centuries, and may have been exacerbated by climate change.




Read more:
Recent Australian droughts may be the worst in 800 years


But the role of climate change in extended drought periods is difficult to discern from normal variations in weather and climate. This is particularly true in Australia, which has a much more variable climate than many other parts of the world.

What does the future hold?

Climate models project increasing temperature across Australia and a continuing decline in cool-season rainfall over southern Australia over the next century. This will lead to more pressure on water supplies for agriculture, the environment, and cities such as Melbourne at the Paris Agreement’s target of 2℃, relative to the more ambitious target of 1.5℃ of global warming.




Read more:
2℃ of global warming would put pressure on Melbourne’s water supply


Rainfall is projected to become more extreme, with more intense rain events and fewer light rain days. Declining overall rainfall is predicted to reduce river flows in southeastern Australia. While we can expect the largest floods to increase with climate change, smaller floods are decreasing due to drier soils, and it is these smaller floods that top up our water supply systems.

Action needed

We might not know enough about droughts to be certain about exactly how they will behave in the future, but this does not affect the message from the science community on climate change, which remains crystal clear.

Rainfall intensification, sea level rise, ocean acidification, hotter days, and longer and more intense heatwaves all point to the fact that climate change presents a major threat to Australia and the world.

In response to these threats, we need deep and sustained greenhouse gas emissions cuts and proactive adaptation to the inevitable effects of climate change. This includes a focus right now on the practical measures to help our rural communities who continue to feel the pinch of a dry landscape.




Read more:
Why 2℃ of global warming is much worse for Australia than 1.5℃


The Conversation


Ben Henley, Research Fellow in Climate and Water Resources, University of Melbourne; Andrew King, ARC DECRA fellow, University of Melbourne; Anna Ukkola, Research Fellow, Australian National University; Murray Peel, Senior lecturer, University of Melbourne; Q J Wang, Professor, University of Melbourne, and Rory Nathan, Associate Professor Hydrology and Water Resources, University of Melbourne

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

We can’t drought-proof Australia, and trying is a fool’s errand



The push to ‘drought-proof’ Australia is dangerous nonsense.
AAP Image/Mick Tsikas

Emma Kathryn White, University of Melbourne

There is a phrase in the novel East of Eden that springs to mind every time politicians speak of “drought-proofing” Australia:

And it never failed that during the dry years the people forgot about the rich years, and during the wet years they lost all memory of the dry years. It was always that way.

While author John Steinbeck was referring to California’s Salinas Valley, the phrase is particularly pertinent to Australia where the El Niño-Southern Oscillation exerts a profound influence. Water availability varies greatly across the country, both in space and time. El Niño conditions bring droughts and devastating bushfires, while La Niña is accompanied by violent rainfall, floods and cyclones.




Read more:
Recent Australian droughts may be the worst in 800 years


This variability is innate to the Australian environment. And now, climate change means that in some regions, the dry years are becoming drier and the wet years are becoming less frequent. Managing water resources under a changing climate and burgeoning population requires innovative and realistic solutions that are different to those that have worked in the past.

Drought-proofing is impossible

Planning for the dry years involves setting sustainable usage limits, using more than one source of water, efficiency improvements, managed aquifer recharge, water recycling and evaluation of the best usage of water resources. It does not involve misleading claims of drought-proofing that infer we can somehow tame the unruly nature of our arid environment instead of planning and preparing for reality.

Unlike managing for the wet and dry periods, drought-proofing seeks to negate dry periods through infrastructure schemes such as large dams (subject to huge evaporative losses) and dubious river diversions. It fails to acknowledge the intrinsic variability of water availability in Australia, and modify our behaviour accordingly.

The reality is that in many parts of the country, groundwater is the sole source of water and the climate is very dry. A cornerstone of the recently launched $100 million National Water Grid Authority is the construction of more dams. But dams need rain to fill them, because without rain, all we have is empty dams. And we have enough of those already.

A history of denial

Just because Dorothea Mackellar wrote of “droughts and flooding rains” over 100 years ago, it doesn’t mean water management should proceed in the same vein it always has.

Australia has always had a variable climate, which changes significantly from year to year and also decade to decade. This not the same as a long-term climatic trend, better known as climate change.




Read more:
“Weather” and “climate” are used interchangeably. They shouldn’t be


Climate change is making parts of Australia even drier. Rainfall in the south-eastern part of Australia is projected to keep declining. We cannot rely on blind faith that rains will fill dams once more because they have in the past.

Yet inevitably, during the dry years, claims that Australia can be “drought-proofed” are renewed. Deputy Prime Minister Michael McCormack recently praised the Bradfield scheme, an 80 year old infrastructure project intending to divert northern river flows inland. It has been so thoroughly debunked on all scales, it is better described as a pipe-dream than piping scheme. It has no place in reasonable water management discourse.

The concept of drought-proofing harks back to the days of European settlement. Early water management techniques were more appropriate for verdant English fields than the arid plains of Australia.

In the early twentieth century, water resources were vigorously developed, with government-sponsored irrigation schemes and large dams constructed. During this time, little thought was given to sustainability. Instead, the goal was to stimulate inland settlement, agriculture and industry. Development was pursued despite the cost and ill-advised nature of irrigation in particular areas.

Shifting long entrenched perceptions of water management

All this said, irrigation certainly has its place: it supports a quarter of Australia’s agricultural output. And there are substantial efforts underway to rebalance water usage between irrigation and the environment.

However, acknowledgement of the relative scarcity of water in certain parts of Australia has only really occurred in the last 30 years or so.

Widespread droughts in the late 1970s and early 1980s highlighted the importance of effective water management and shifted long-entrenched perceptions of irrigation and development. Water reforms were passed, mandating future water development be environmentally sustainable development, which meant, for the first time, water resource management sought a balance between economic, social and environmental needs.

Antiquated ideas about drought-proofing, pushed by politicians, promise much yet deliver little. They distract attention and siphon funds from realistic solutions, or actually re-evaluating where and how we use our limited water resources.




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The air above Antarctica is suddenly getting warmer – here’s what it means for Australia


We need practical, effective and well-considered management such as water recycling, efficiency measures and source-divestment that accounts for both shorter term climatic variability and long term changes in temperature and rainfall due to climate change. A big part of this is managing expectations through education.

Attempting to drought-proof Australia is not “managing for the dry periods”, as advocates claim. It is sticking our heads in the dry, salty sand and pretending the land is cool and green and wet.The Conversation

Emma Kathryn White, PhD Candidate, Infrastructure Engineering, University of Melbourne

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