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.




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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.




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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.




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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.




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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.

Don’t blame the Murray-Darling Basin Plan. It’s climate and economic change driving farmers out


Sarah Ann Wheeler, University of Adelaide

For the thousand or so farmers in Canberra in the past week venting their anger at the federal government, it’s the Murray-Darling Basin Plan to blame for destroying their livelihoods and forcing them off the land.

We can’t comment directly on their claims about the basin plan. But our research, looking at the years 1991 to 2011, suggests little association between the amount of water extracted from the Murray-Darling river system for irrigation and total farmer numbers.

That’s not to say there aren’t fewer farms in the basin now than a decade ago – there are – but our analysis points to the more important drivers being the longer-term influences of changing climate, economics and demographics.

Indeed our study predicts another 0.5℃ increase in temperature by 2041 will halve the current number of farmers in the basin.

Hostility to water recovery

The waters of the northern basin run to the Darling River and the waters of the southern basin run to the Murray River.
MDBA

Over many decades state governments in Queensland, New South Wales, Victoria and South Australia licensed to farmers more entitlements to water than the river system could sustain. The basis of the Murray-Darling Basin Plan, enacted in 2012, was to rectify this through buying back about a quarter of all water licences to ensure an environmental flow.

A water entitlement, despite its name, does not guarantee a licence holder a certain amount of water. That depends on the water available, and that is determined by the states, which make allocations to each type of licence based on its type of security and current conditions.

With drought, farmers have seen their allocations severely cut back, sometimes to nothing. And partly because they see there’s still water in the River Murray, some are very angry.




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Hostility to water recovery in fact predates the plan’s enactment, to when the federal government began buying back water entitlements in 2008. The Commonwealth now holds about 20% of water entitlements across the basin. More than two-thirds of these licences were recovered between 2008 and 2012.

Lack of correlation

Our research thus covers the period of most significant water buybacks. It also covers the period of the Millennium Drought, from 2001 to 2009, when the amount of water extracted from the river system dropped by about 70%.

Yet we see little evidence reduced water extractions led to more farmers exiting the industry.

As a very broad overview of the situation, the following graph illustrates the lack of correlation between measured water extraction in the Murray-Darling Basin and decreasing farmer numbers.



Water extractions have varied significantly between years, with a big decline over the decade of the 2000s even while farmers’ need for irrigated water increased due to lack of rain. La Niña brought record rains in 2010-11. The current drought across the basin took grip from about 2017.

Yet farmer numbers have declined at a relative steady rate. Within the basin in the time-period we modelled, they fell from about 90,000 in 1991 to 70,000 in 2011. This can be seen as part of a wider trend, with total farmer numbers in the four basin states falling from more than 230,000 in 1976 to barely 100,000 in 2016.

It might be argued that because irrigated farms make up only a quarter of all farms, the overall numbers might mask a greater correlation between water extractions and decline in irrigated farms. While the specific impacts on irrigation farming in recent years warrant further study, there’s no signal in our data pointing to extractions making a discernible contribution to farmer numbers throughout the basin.

Modelling farmer movement

Our findings are based on a specialised data set of population and agricultural census information from statistical local areas from 1991 to 2011. We used climate risk measures from 1961 onwards.

The following infographic shows the exit pattern of farmers by local area between 1991 and 2011.



We included as many climate, economic, farming, water and socio-demographic characteristics as possible to capture historical farmer movements and create a model able to predict movements based on variables such as average temperature.

Need for a multifaceted response

Overall our modelling results suggests the most significant and largest influences on farmer exit are rising temperatures and increased drought risk, followed by the economic factors that have have been reducing the proportion of the population engaged in farming for more than a century.

Declining commodity prices, higher unemployment and urbanisation are strongly associated with farmer exit. Urbanisation, for example, has made it attractive for farmers on city fringes to sell their land to property developers and exit the industry.

Research suggests irrigators in psychological distress are more likely to want the basin plan suspended. Our research suggests their distress is probably not primarily driven by the federal government buying water entitlements from licence holders who sold them willingly. Water recovery and the basin plan is simply an easier focal point of blame than the longer-term trends making the farming lifestyle less viable.




Read more:
Scarcity drives water prices, not government water recovery: new research


Nothing will be gained by focusing on short-term “fixes” at the cost of longer-term environmental harm. The problems facing all farmers cannot be addressed in isolation from longer-term global climate and economic trends.

As a society we have to decide what we value: do we want to see such a mass exodus of farmers from the land in the face of a drying climate? If not, future policy for the Basin must consider the real long-term drivers of farm exit and take a multi-faceted approach to climate change, water, land, drought and rural development.The Conversation

Sarah Ann Wheeler, Professor in Water Economics, University of Adelaide

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

Drought and climate change were the kindling, and now the east coast is ablaze



Multiple large, intense fires are stretching from Australia’s coast to the tablelands and parts of the interior.
AAP Image/Supplied, JPSS

Ross Bradstock, University of Wollongong and Rachael Helene Nolan, Western Sydney University

Last week saw an unprecedented outbreak of large, intense fires stretching from the mid-north coast of New South Wales into central Queensland.

The most tragic losses are concentrated in northern NSW, where 970,000 hectares have been burned, three people have died, and at least 150 homes have been destroyed.

A catastrophic fire warning for Tuesday has been issued for the Greater Sydney, Greater Hunter, Shoalhaven and Illawarra areas. It is the first time Sydney has received a catastrophic rating since the rating system was developed in 2009.

No relief is in sight from this extremely hot, dry and windy weather, and the extraordinary magnitude of these fires is likely to increase in the coming week. Alarmingly, as Australians increasingly seek a sea-change or tree-change, more people are living in the path of these destructive fires.




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Unprecedented state of emergency

Large fires have happened before in northern NSW and southern Queensland during spring and early summer (for example in 1994, 1997, 2000, 2002, and 2018 in northern NSW). But this latest extraordinary situation raises many questions.

It is as if many of the major fires in the past are now being rerun concurrently. What is unprecedented is the size and number of fires rather than the seasonal timing.

The potential for large, intense fires is determined by four fundamental ingredients: a continuous expanse of fuel; extensive and continuous dryness of that fuel; weather conditions conducive to the rapid spread of fire; and ignitions, either human or lightning. These act as a set of switches, in series: all must be “on” for major fires to occur.

Live fuel moisture content in late October 2019. The ‘dry’ and ‘transitional’ moisture categories correspond to conditions associated with over 95% of historical area burned by bushfire.
Estimated from MODIS satellite imagery for the Sydney basin Bioregion.

The NSW north coast and tablelands, along with much of the southern coastal regions of Queensland are famous for their diverse range of eucalypt forest, heathlands and rainforests, which flourish in the warm temperate to subtropical climate.




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These forests and shrublands can rapidly accumulate bushfire fuels such as leaf litter, twigs and grasses. The unprecedented drought across much of Australia has created exceptional dryness, including high-altitude areas and places like gullies, water courses, swamps and steep south-facing slopes that are normally too wet to burn.

These typically wet parts of the landscape have literally evaporated, allowing fire to spread unimpeded. The drought has been particularly acute in northern NSW where record low rainfall has led to widespread defoliation and tree death. It is no coincidence current fires correspond directly with hotspots of record low rainfall and above-average temperatures.

Annual trends in live fuel moisture. The horizontal line represents the threshold for the critical ‘dry’ fuel category, which corresponds to the historical occurrence of most major wildfires in the Bioregion.
Estimated from MODIS imagery for the Sydney basin Bioregion

Thus, the North Coast and northern ranges of NSW as well as much of southern and central Queensland have been primed for major fires. A continuous swathe of critically dry fuels across these diverse landscapes existed well before last week, as shown by damaging fires in September and October.

High temperatures and wind speeds, low humidity, and a wave of new ignitions on top of pre-existing fires has created an unprecedented situation of multiple large, intense fires stretching from the coast to the tablelands and parts of the interior.

More people in harm’s way

Many parts of the NSW north coast, southern Queensland and adjacent hinterlands have seen population growth around major towns and cities, as people look for pleasant coastal and rural homes away from the capital cities.

The extraordinary number and ferocity of these fires, plus the increased exposure of people and property, have contributed to the tragic results of the past few days.




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Communities flanked by forests along the coast and ranges are highly vulnerable because of the way fires spread under the influence of strong westerly winds. Coastal communities wedged between highly flammable forests and heathlands and the sea, are particularly at risk.

As a full picture of the extent and location of losses and damage becomes available, we will see the extent to which planning, building regulations, and fire preparation has mitigated losses and damage.

These unprecedented fires are an indication that a much-feared future under climate change may have arrived earlier than predicted. The week ahead will present high-stakes new challenges.

The most heavily populated region of the nation is now at critically dry levels of fuel moisture, below those at the time of the disastrous Christmas fires of 2001 and 2013. Climate change has been predicted to strongly increase the chance of large fires across this region. The conditions for Tuesday are a real and more extreme manifestation of these longstanding predictions.




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Whatever the successes and failures in this crisis, it is likely that we will have to rethink the way we plan and prepare for wildfires in a hotter, drier and more flammable world.The Conversation

Ross Bradstock, Professor, Centre for Environmental Risk Management of Bushfires, University of Wollongong and Rachael Helene Nolan, Postdoctoral research fellow, Western Sydney University

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.




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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.




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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:
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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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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.