BOM forecasts wet autumn for some as La Niña weather system declines


The much-discussed La Niña phenomenon has brought the best wet season for years in the Top End and a welcome change to rainier conditions for most of the country, but some still missed out this summer.

And the Bureau of Meteorology [BOM] autumn outlook is for wetter-than-average conditions in the east.

According to BOM climatologist Naomi Benger, La Niña will continue to wield influence into autumn even though it is weakening.

“The typical lifecycle of La Niña is that it decays through autumn,” she said.

“We are expecting it to decay through early autumn, but we are still seeing quite strong signals in the atmosphere, even though some of the oceanic measurements are hinting towards the decay.”

Hence, encouraging signs of rain in areas that need it.

“We are expecting above average rainfall in eastern and some northern parts, including those parts of Queensland that have missed out so far this year,” Dr Benger said.

And cyclone season isn’t over until the end of April.

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Above-average minimum temperatures are expected to continue across most of the country, with the exception of central and western South Australia and south-eastern Western Australia.

Daytime temperatures are expected to be above average for the far north and south as well as the far west.

Bring on the wet

So far, La Niña’s impact has fallen well short of infamous flood years like 2011 and 1974.

Summer still has a few days to go and, according to Dr Benger, rain has been above average for the nation as a whole and the highest seen since the summer of 2016-17.

The Top End is finally enjoying a wet season worthy of the name after the last two failed. The Red Centre is tinged with green and Uluru’s valleys have become waterfalls several times this summer.

It has rained on the rock several times this wet season.(ABC Weather: Kate Doyle)

Trevor Durling, senior planning engineer at the Northern Territory Power and Water Corporation, said its water supply security is currently well placed thanks to the above average rains they have had so far across the Territory.

“The Darwin River Dam is currently at approximately 80% capacity, the highest it has been since 2018, when it last overflowed,” he said.

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The level dipped as low as 50% capacity prior to this wet season’s rains.

“With the ground saturated, we are expecting further runoff into the reservoir from the catchment regardless of how much additional rain there may be,” according to Mr Durling.

“There are still two months of the wet season ahead, so we anticipate further good rainfall in the Top End region.”

Fiery in the south-west

For Western Australia, the biggest impacts of the La Niña weather pattern have been felt in the water.

For most of January WA’s vast coastline was under marine heatwave conditions, 2-3 degrees above average in Geraldton and Broome.

Like the Northern Territory, pastoralists in WA’s north are also hailing it “the best start to the wet season” in years.

But as in the years preceding it, La Niña has brought little rain for southern Western Australia, with little reprieve for firefighters facing challenging conditions.

A map that shows average to low rainfall in south west WA and parts of QLD.
The map shows rainfall anomalies for Australia in December 2020 and January 2021. Average to below areas can be seen around southern WA and Queensland.(Bureau of Meteorology)

A rainfall deficit in the winter and spring made southern WA one of the few places with “above normal” fire severity for December to February. Inner New South Wales and the ACT were also rated above normal.

Department of Fire and Emergency Service (DFES) WA rural fire division executive director Murray Carter said crews had battled several fires this year, the worst of them the Wooroloo bushfires, in Perth’s east, which destroyed 86 homes this month.

A plume of red smoke in the distance, taken from a hill in Bullsbrook.
Flames and smoke rise from the massive Wooroloo bushfire, as seen from a property in Bullsbrook.(Supplied: Rachael Harpley)

Mr Carter said a slow-moving tropical low that inundated the Gascoyne region at the start of this month had provided some benefit to the southern part of the state.

In the space of two days in February, Perth received almost three times its monthly average of rain.

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“It’s taken us from above average and worrying conditions to average,” Mr Carter said.

But he warned the bushfire season was far from over.

“Western Australia will be on an average outlook but I don’t want to sell that short because average for us is still serious fire conditions,” he said.

Bushfire outlook

That was a sentiment echoed by John Bates, research director at the Bushfire and Natural Hazards Cooperative Research Centre.

The official autumn bushfire outlook, also released today, suggests most of the country can expect average fire conditions this autumn.

map of Aus showing above average fire potential in parts of Qld but below normal for northern Qld and parts of Vic
Fire conditions are expected to be normal for most of the country.(Bushfire and natural hazards CRC)

But according to Dr Bates the risk of grass and crop fires continues in the coming months, particularly where rain has created good growing conditions.

“Autumn will still see hot and windy days that raise the fire risk in some locations,” he said.

Areas that have missed out on rain so far in Queensland are at above average risk.

“But when the weather conditions allow, the March to May period is a good time of year for prescribed burning,” according to Dr Bates.

Map of Aus mainly white but red for the coasts and for Tas
Maximum temperatures are expected to be average for much of continental Australia but above average around the coasts and for Tasmania.(Bureau of Meteorology)

“However, in northern Australia, the good wet season means that prescribed burning will be difficult in the coming months.”

We hope you enjoyed checking out this story involving Northern Territory and Australian news called “BOM forecasts wet autumn for some as La Niña weather system declines”. This news update was shared by MyLocalPages Australia as part of our news aggregator services.

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Novak Djokovic v Frances Tiafoe, Nick Kyrgios v Ugo Humbert, Serena Williams v Nina Stojanovic results, schedule, draw, scores, odds, order of play, dates, start time


Novak Djokovic (1) v Frances Tiafoe

Night session from 7pm AEDT:

Caroline Garcia v Naomi Osaka (3)

Maxime Creesy v Alexander Zverev (6)

MCA

Aryna Sabalenka (7) v Daria Kasatkina

Sorana Cirstea v Petra Kvitova (9)

Dominic Thiem (3) v Dominik Koepfer

Night session from 7pm AEDT:

Ajla Mljanovic v Simona Halep (2)

Grigor Dimitrov (18) v Alex Bolt

John Cain Arena (from midday AEDT)

Stan Wawrinka (17) v Marton Fucsovics

Venus Williams v Sara Errani

Iga Wiatek (15) v Camila Giorgi

Night session from 7pm AEDT:

Nick Kyrgios v Ugo Humbert (29)

1573 Arena

Marketa Vondrousova (19) v Rebecca Marino

Alexandre Muller v Diego Schwartzman (8)

Garbine Muguruza (14) v Liudmila Samsonova

Reilly Opelka v Taylor Fritz (27)

Thank you for stopping by and checking this article involving current Queensland News called “Novak Djokovic v Frances Tiafoe, Nick Kyrgios v Ugo Humbert, Serena Williams v Nina Stojanovic results, schedule, draw, scores, odds, order of play, dates, start time”. This news article was presented by My Local Pages Australia as part of our local news services.

#Novak #Djokovic #Frances #Tiafoe #Nick #Kyrgios #Ugo #Humbert #Serena #Williams #Nina #Stojanovic #results #schedule #draw #scores #odds #order #play #dates #start #time



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La Nina points to a cooler and damper summer for Victoria


While final figures will be released next week, Victoria’s 2020 was the mildest year for daytime temperatures in nine years. Average daily temperatures were about 0.39 degrees above the 1961-90 yardstick used by the bureau.

For Australia as a whole, 2020 was the fourth hottest on record for mean temperatures and fifth hottest for maximums. Both measures trailed the scorcher in 2019 that smashed many records.

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Victoria’s annual rainfall last year of 671 millimetres was back above the long-run average for the first time since 2016, and for only the second time since 2011.

As it happens, 2011 was also the last time Australia was under the influence of a strong La Nina pattern in the Pacific. During La Ninas, rainfall tends to shift westwards along the equator, pushing rainfall totals above normal levels for most of eastern Australia, including Victoria.

The bureau declared such an event to be under way in late September and “we’re seeing a fairly typical La Nina signal” now, Dr Trewin said.

That means, according to the Bureau of Meteorology’s longer-term outlook, Victoria can expect odds of about 70 per cent of higher-than-normal rainfall for the first quarter of 2021.

“A few areas will miss out” but for most of the state that means rain gauges will probably be fuller than usual for these months, Dr Trewin said.

With all the cloud around, the odds favour temperatures during the days being average to even cooler than normal, except for areas close to the coast. That’s true for most of the rest of Australia.

One risk, as in 2011, is for some of the extra tropical moisture around to make its way all the way south. Under the right conditions, Victoria could experience some flooding.

The relative lack of clear skies, though, will also keep overnight temperatures from dropping as much as usual.

That prediction is strong for almost the whole country too, with the exception of a portion of inland Western Australia, where few holidaymakers would venture even if borders were open.

Another feature of La Nina years is that while extra rainfall tends to keep a lid on daytime temperatures at least, heatwaves can still happen across southern Australia but without packing days of extreme heat.

Instead, “you can get more prolonged spells of moderate heat”, Dr Trewin said, adding “there’s no indication of any significant heat in the near future for south-east Australia”.

Even though La Nina tend to be on the cooler end of the natural variation, the background warming from climate change means that even the cool years remain relatively warm on a local and global scale.

For Melbourne, the coming week’s forecast is for most days to be partly cloudy with a temperature range of 14 to 27 degrees over the period. Sunday’s chance of storms could bring the wettest of those days.

The damper conditions also mean fire-danger ratings are suppressed. By Saturday, all but the Wimmera, Mallee and East Gippsland will be at the lowest end of the scale for fire risk.

Still, it doesn’t take a lot of heat, particularly in the state’s north-west, for conditions to be dry enough to support bushfires, as shown during the burst of warmth last month, Dr Trewin said.

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Canberra faces increased grass fire risk, power outages and allergic reactions this summer thanks to La Niña


The wet spring season might have eased the threat of serious bushfires over coming weeks for Canberra, but La Niña is throwing up different challenges for the Territory.

Just a few months ago, the ACT Government was working to rescue trees that were suffering under record-breaking heat and low rainfall, threatening Canberra’s urban forest.

This spring is the opposite.

The arrival of La Niña brings with it higher rainfalls (133.6mm was recorded at Ainslie in October alone, the highest rainfall for the month since 1983), and with that increased risk of flood.

But there are also less obvious consequences: the wet spring is causing rapid growth with trees and grass, and accredited arborists have been inundated with requests to trim trees growing near power lines.

“Since spring we have just got busier and busier to the point where we are notifying clients that we have got 16-week waits on work at the moment,” senior arborist Kieran Wallace said.

Emily Dibden says rain is complicating matters.(ABC News: Isaac Nowroozi)

Mr Wallace said it was important that power lines were clear of vegetation to prevent power outages and fires, something fellow arborist Emily Dibden said rain had complicated.

“The rain brings more work but it is also harder to do work around power lines,” she said.

“There is a huge danger aspect to this work so sometimes we have just been totally rained out, so it is great for growth but hard to work in.”

The risks posed by tree growth is just one of several unexpected challenges Canberrans face this summer due to the La Niña weather event.

Tall grass obscures the Canberra tower.
The Emergency Services Agency is warning people to be wary of grass fires.

Wild growth leading to grass fire concerns

Peter Sullivan from the City Services directorate said heavy rainfall over the past few weeks had made it difficult to keep up with mowing long grass across the city ahead of summer.

“Our staff are working seven days a week, 12-hour days because of the excessive growth from the La Niña event,” Mr Sullivan said.

This week, the ACT Government invested an extra $6 million for grass cutting across Canberra.

The concern is that the risk of grass fires is growing, as high rainfall grows and re-grows grasses faster.

Longs grasses grow over a narrow path.
Rapid grass growth is overwhelming maintenance teams and causing high pollen loads.(ABC News: Jordan Hayne)

The Emergency Services Agency has warned Canberrans to be wary of grass fires.

“It has been difficult due to the wet conditions and we have had mowers getting bogged at times,” Mr Sullivan said.

City Services say they will do whatever it takes to get on top of it all to minimise the risk.

More plant growth equals more pollen

The wet spring has also led to record levels of grass pollen, and the worst hayfever season in more than five years, according to the Australian National University.

“We have seen (pollen) numbers that we have actually never recorded before in the region,” said Professor Simon Haberle, from the ANU’s pollen monitoring program.

It has led to ACT Health issuing a warning last week and pharmacists have reported a rush on strong allergy medicine this spring.

“People start to feel the effects of grass pollen in the air when it is at moderate levels,” Professor Haberle said.

That is about 20 grains per cubic metre.

“When it goes above 50 grains per cubic metre is when it becomes much more severe,” he said.

“We have been recording quite a number of those.”



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La Niña has storm chasers ready for thrilling season of weather events


The storm-chasing world has changed dramatically from pre-internet days to today’s modern technology, including a recently used 3D radar that may revolutionise the study of weather.

But one thing remains the same — the desire to capture the perfect storm.

And with the Bureau of Meteorology advising that Australia is experiencing a La Niña event — meaning increased rainfall and the potential for more tropical lows and cyclones affecting the east coast — there will likely be plenty of opportunities for storm chasers in the near future.

But what drives these storm enthusiasts to chase the perfect storm?

‘That first cumulus cloud’

Higgins Storm Chasing’s Thomas Hinterdorfer says it is part adrenalin and part the desire to understand a natural phenomenon.

“Seeing that first cumulus cloud, watching it evolve into this amazing photogenic beast and then watching it diminish.”

But Mr Hinterdorfer says the ability to stream weather events to social media and relay information live without delay has created a generation of amateur weather enthusiasts.

“There are a lot of storm chasers that simply don’t go into the storm,” he said.

“They love to sit back, and at the end of the day they can take some of the best photos.”

Tornado ‘the holy grail’

Michael Bath says the 1987 Lismore floods triggered his obsession with storm chasing.(Supplied: Michael Bath)

Michael Bath’s fascination with weather was sparked by the 1987 Mother’s Day flood in Lismore.

“There’s a group of obsessed ones, and I’d class myself as one of those,” he said.

In 2013, Mr Bath was setting up a camera on a tripod hoping to catch a few lightning bolts when a tornado ripped through the northern tablelands of New South Wales, between Glencoe and Guyra.

Northern Tablelands NSW tornado 2013
Michael Bath has witnessed the 2013 tornado that ripped through the northern tablelands of NSW.(Supplied: Michael Bath)

“We could tell that there was rotation there even though the storm was 10 to 15 kilometres away at that point,” he said.

It is the structure and beauty of the thunderstorms, the lightning, the hail and the wind that Mr Bath finds so captivating to photograph.

“Ideally with lightning, you want to be a couple of kilometres from where it is happening, so that when you’re taking photographs, the lightning is going to fill the entire frame of your camera,” he said.

“It’s just that extra beauty with all of those spectacular colours that are occurring around that time.”

McLeans Ridges NSW sunset storm
Weather watcher Michael Bath captured this unusual sunset in McLean’s Ridges with a sun pillar.(Supplied: Michael Bath)

It is the bigger storms with amazing structures and colours that gives Mr Bath “a goosebump-type feeling”.

“It’s the fear of missing out and a buzz when you do cop some severe weather,” Mr Bath said.

However, Mr Bath says he knows not everyone was fascinated by the spectacle.

“A large percentage of the population loves looking at a thunderstorm — unless they’ve had some horrible experience and are scared by them. I can certainly appreciate that too,” he said.

Mr Bath says there are different groups of storm chasers, and not all are “the type of people who will travel to the United States or travel for hundreds and hundreds of kilometres a day just to find storms in another area”.

‘A truly incredible spectacle’

Nine Media photographer Nick Moir has travelled to the United States to chase and photograph storms.

He says while Australia may not be able to compete with America when it comes to tornadoes, Australia can get some “pretty big hail”.

The recent hail event that hit south-east Queensland, the Northern Rivers and Mid North Coast of New South Wales between October 29 and 31 produced giant hail in some areas.

Bonville 31 October hail stone
Giant hail hit Bonville on the Mid North Coast on October 31, 2020.(Supplied: Dionne Arthur)

“Some of those hail stones were monsters and you would have seen some strange shapes,” Mr Moir said.

Mr Moir said when a storm turned into a long-lived supercell they become “very organised”.

“You can see all these inflows and outflows,” he said.

“It is a truly incredible spectacle it does make you feel small.”

Tornado Alley in the United States is a popular destination for Australian chasers wanting their next challenge.

“Many Australians go over each year and test their skills out in the United States, it really is a proving ground for forecasters” Mr Moir said.

No longer the “private little weird group”, Mr Moir says it is a lot easier to become a storm chaser because there is a lot of information now about how to start storm chasing. And he is happy to part with his own secrets.

“You need to have plenty of moisture to really get that storm down low to really see the amazing structure, so that is why this year is good for storm chasers.”

‘A very big beast’

For Mr Hinterdorfer storms provide an opportunity to see the sheer power and might of Mother Nature.

“Weather is a very, very big beast.

“It’s the ability to see something so raw, nothing is going to stop it, and so when you see those perfect elements come into play it honestly can make your jaw drop and speechless.”

Largest recorded hail stone

Bureau of Meteorology researcher Joshua Soderholm says the largest recorded hailstone in the Australian severe storms archive had a diameter of 14 centimetres and fell at Kempsey in New South Wales in 1991.

The largest reported hailstone from the weather event of October 31 in south-east Queensland was also 14cm in diameter, falling in the Brisbane suburb of Forestdale.

Giant hail stone
A 13.5cm hail stone that fell in Forestdale, south-east Queensland on October 31, 2020.(Supplied: Simon Filipowicz)

“The hail that was observed at Forestdale of 14cm in diameter was actually the largest recorded hailstone in Queensland,” Mr Soderholm said.

“It’s always important to point out that it might have occurred before further inland away from heavily populated areas of Queensland, it just hasn’t been measured before.”

However, he says, an extreme hail event such as that of October 31 is not a regular occurrence.

“These extreme hail events might only occur every 10, 20, 30 years, so we actually don’t have the historical record or the data to build up a robust understanding yet.”

New 3D weather radar technology

Weatherwatch meteorologist Anthony Cornelius said they used a new 3D weather-watching tool during the October 31 hail event to estimate the hail’s diameter in south-east Queensland.

He said the tool also identified every severe hail storm that was occurring in the region on the day as well as predicted the storms that would produce giant hail.

3D radar technology
Weatherwatch meteorologist Anthony Cornelius says they used a new 3D radar technology during the October 31, 2020 hail storm.(Supplied: Anthony Cornelius)

Mr Cornelius said hail could be catastrophic and costly, and the new technology would hopefully lead to a better prediction of the weather event.

“The recent hail storm we’ve just had, the Sydney hail storm of 1999, Brisbane 2014 and 1985. [They were] all billion-dollar [damage] hail storms,” he said.

Safety first, storm chasers warned

Mr Moir warns newbie enthusiasts to be always careful of lightning in storms.

“Even the smallest storm can produce lightning, and it really is a bit random where it will hit,” he said.



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La Niña: What it will mean for Tasmania


Australia’s climate is highly variable from year to year.

Much of this variability relates to the oscillation between El Niño and La Niña events, known as the El Niño — Southern Oscillation (ENSO).

The ENSO is a major seesaw in ocean temperature, air pressure and rainfall patterns between the Australian/Indonesian region and the eastern Pacific Ocean.

El Niño was first recognized by fishermen off the coast of South America in the 1600s when unusually warm water appeared at the surface in the eastern tropical Pacific Ocean.

The name El Niño means The Little Boy, or Christ Child in Spanish, and was chosen based on the time of year (around December) when these warm water events often reached their peak.

La Niña is El Niño’s opposite phase, when the eastern tropical Pacific Ocean is much cooler than normal.

La Niña means The Little Girl in Spanish.

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What is La Niña?

Under normal or ‘neutral ENSO’ conditions, the surface of the western tropical Pacific Ocean to the northeast of Australia is typically around 28 to 30 degrees Celsius, making it a source of cloudiness and rainfall.

This is considerably warmer than the surface of the eastern tropical Pacific, which is around 20C near South America.

Easterly trade winds (flowing from east to west) along the equator cause the ocean currents in the eastern Pacific to draw water from the deeper ocean, helping to keep the surface cool.

This means the waters in the western tropical Pacific can warm more than those in the east under the influence of the sun.

During La Niña events, these easterly trade winds strengthen, which causes the central and eastern tropical Pacific to become even cooler than normal, and the western tropical Pacific to become warmer than normal.

La Niña episodes typically last nine to 12 months, but some prolonged events may last for years.(Instagram: ryan_shanz)

Cloudiness and rainfall are enhanced to the north of Australia, which typically leads to above average rainfall for northern, central, and eastern parts of the country, and below-average daytime temperatures south of the tropics.

With more cloud and rain than normal, La Niña can also bring widespread flooding to Australia.

La Niña events occur about every three to seven years.

Blue tongue lizard with fire in the distant background.
A wet spring also means more vegetation growth and possible increased risk of grass fires during summer.(Supplied: Alice Reddington)

An event usually begins to develop in autumn or winter, strengthens through winter-spring, and reaches its peak late in the year before finishing the following autumn.

La Niña episodes typically last nine to 12 months, but some prolonged events may last for years.

The previous La Niña event lasted from 2010 to 2012 and was one of the strongest La Niña events on record.

It produced Australia’s second wettest two-year period on record and caused significant flooding in many parts of Australia, including eastern Tasmania.

When there is a La Nina the Walker Circulation intensifies bringing wet and warm conditions to Australia(Supplied: Bureau of Meteorology)

What does La Niña mean for Tasmania?

The effects of La Niña on the climate of Australia, including Tasmania, vary from event to event.

The typical springtime impact shows above-average rainfall in Tasmania, particularly over the northeast, while La Niña’s impact during summer is typically less than during spring.

The rainfall responses to La Niña are shown in the map below.

It should not be expected that rainfall in any given La Niña year will follow the typical patterns in each map.

Two maps of Australia showing rainfall levels across spring and summer in La Niña years.
Composite rainfall in spring and summer across La Niña years.(Supplied: BOM)

The other impact upon Tasmania can be in our surrounding oceans.

When La Niña builds up warmer water in the western Pacific Ocean, it often pushes this warm water between the islands of Indonesia and down the Western Australian coast.

Several months later this warm water can reach Tasmania, increasing the ocean temperatures.

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What can Tasmania expect this summer?

A La Niña event is now underway in the tropical Pacific.

This event started relatively late in the year — September 2020 — and international climate models we survey indicate it will persist through the summer 2020-21.

It is not likely to reach the same intensity as the 2010-12 La Niña event.

Current climate outlooks indicate that November 2020 to February 2021 is likely to be wetter than average across Tasmania, except for the west coast.

Temperatures are likely to be above average as well.

Sunset over Hobart's Mount Wellington/kunanyi with sailboats on the Derwent.
The temperatures of the ocean around Tasmania are also forecast to be above average during spring and into summer.(Supplied: Flight Risk Photography)

Ocean temperatures around Tasmania are also forecast to be above average during spring and into summer, which may be partly influencing the temperature outlook for Tasmania.

The north and north east of Tasmania are particularly likely to be impacted by the above-average rainfall during spring and into summer.

More rainfall, wetter soils, and higher rivers brings an increased risk of flooding to Tasmania.

A wet spring also means more vegetation growth, meaning there could be an increased risk of grass fires during summer.

A La Niña typically means fewer extreme heat days, but heatwaves may last longer and be more humid.

Dr Andrew Marshall is a senior research scientist at the Bureau of Meteorology



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NSW farmers welcome ‘unbelievable’ rain as BOM warns La Niña could ‘swing from drought to flood’


After four punishing years, the drought has finally broken at Rick Bennett’s farm in central-west New South Wales.

His paddocks have been transformed from brown to a lush green and he’s about to harvest his first crops since the start of the big dry.

“You sort of got to pinch yourself every now and then to see crops doing so well after the drought,” he told 7.30.

“It’ll be unbelievable in November, sitting in a [harvesting] header, watching the crops come in the front. Financially and emotionally, it’ll probably be one of the best things I’ve felt for a long time.”

This time last year 99 per cent of New South Wales was drought affected or in drought. Now, that’s down to just over 20 per cent.

About 65 per cent of the state is drought free and the rest is classed as recovering.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume.
Rick Bennett’s nearly-naked dance was seen by thousands of people after last year’s rain.

Mr Bennett’s fortunes began to change in November, when he received his first decent rainfall in months.

He celebrated with a run in the rain, in a video that went viral.

Since then he’s had another 450 millimetres and will harvest wheat, oats and barley in about a month’s time.

“Harvesting a good crop would … definitely start to claw our way back into normal life again, put some money in our bank account, get out of overdraft and just completely turn our world around,” he said.

La Niña poses risk of swinging ‘from drought to flood’

Karl Braganza from the Bureau of Meteorology (BOM) said it appeared the long dry spell was finally over in New South Wales after a La Niña weather event was declared last month.

But that could spell disaster for grain growers at harvest time.

“What that [La Niña] typically means for Australia almost always is we get at least average to above average spring rainfall,” Dr Braganza told 7.30.

“It would be nice if we got just the right amount of rainfall and it didn’t swing from drought to flood, but that typically is what happens at the end of the prolonged drought period in Australia.”

Farmer Martin Honner, wearing a high-vis work top, stands with his arms folded near machinery in a shed.
Martin Honner says farmers have been noticeably happier after a good winter rainfall.(ABC News: Rosie King)

Martin Honner runs a sheep, cattle and cropping property near Junee in south-west New South Wales.

He’s expecting a bumper crop this year after the prolonged drought, but is worried about La Niña.

“Too much rain could probably downgrade the value of the grain through the harvest,” he told 7.30.

“We’ve been very blessed this year but we just need things to fall right for the rest of the year.

A dry, brown landscape dotted with brown trees.
Martin Honner’s farm was left brown and dry during years of drought.(Supplied)

Mr Honner said the drought had taken a huge toll on the farming community but spirits had been lifted by this year’s good winter rainfall.

“The last four, five years, the toughest I’ve seen in my life,” he said.

“All your bad years will disappear if you have a couple of good years.

“Everyone’s a lot happier and you notice it when blokes get together and there is a zest in their step.

Despite predictions of above average spring rainfall, the BOM warned southern Australia would likely spend more time in drought in the future.

“When we look back at the federation drought, the World War II drought and the millennium drought and this drought, certainly the last two droughts have been the hottest on record,” Dr Braganza said.

“So that’s why we think there’s an influence of climate change on those [droughts].”

‘Elixir of life’ brings nature back

Brendan Cullen, a farmer in a blue shirt and hat, smiles happily at the camera.
Brendan Cullen is focusing on the good news of increased rainfall.(ABC News: Carl Saville)

Brendan Cullen manages Kars Station, about an hour south of Broken Hill.

He’s not too worried about long-term predictions, he’s just happy the drought appears over.

“Last year, we had a bit over four inches or 100mm. This year we’re well over [the] 100mm mark now,” he said.

He said in just the past month and a half alone, the station had recorded 60mm of rain.

“The lambs are in very good condition, the ewes are in very good condition, this pastoral country is full of protein,” he said.

For the first time in more than three years, Sturt Desert Peas have sprung up on the property.

A close-up photograph of a Sturts Desert Pea, which is red with black spots.
The distinctive Sturt Desert Pea has made a comeback this year.(ABC News: Angelique Donnellan)

“I see life … three, four years of drought it’s a long wait… once you do get that rain, everything just shoots up beneath you, it’s amazing,” he said.

“I think it’s the elixir of life, ultimately if you’re in the rural industry your life is revolved around rain.”



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Bushfires, buffel, bombers and La Niña


By ERWIN CHLANDA

The impending bushfire season will be less dangerous because of the drought but fuel – mostly buffel, which in South Australia is declared a weed – is likely to build up again if La Niña is true to her reputation for bringing rain.

“Buffel grass in low-lying water drainage lines was the major driver” of fire that burnt about half of the West MacDonnell National Park in the summer of 2018/19, according to Josh Fischer, Assistant Director of Bushfires NT.

And he says bringing in water bombers was considered but rejected because of cost-benefit considerations.

It’s clear the landscape itself is not regarded as an asset worth saving, its prime value to the tourism industry notwithstanding.

Fire prevention and fighting is focussed on “life and property” such as rangers houses and buildings linked to the tourism industry.

Yet controlling buffel on the ground is near impossible because of the park’s sheer size.

Mr Fisher makes it clear that dealing with fires is the responsibility of the land’s owners: In the case of the park these are the Aboriginal people holding inalienable freehold title under land rights, leased to the NT government’s parks service for management and public use.

Gum burnt in West Macs blaze.

In the case of cattle stations the pastoral lessees are responsible.

He says “lots of lessons” have been learned from the massive fires in the 2018/19 summer and discussions are under way right now to formulate strategies for preventing a repeat of the disaster.

There have been 420 fires across the NT in 2020 so far.

What can be done about buffel?

Land owners need to “instal strategic fire breaks whether they be graded, slashed, sprayed or burnt, effectively breaking the landscape up so there are areas of low or no fuel to halt the spread of a wild fire if one is to start,” says Mr Fischer.

This year there was little need for this because of the low amount of fuel, and pastoral land holders needed to keep what little feed there was for their stock.

In the Alice Springs fire management zone during 2017 about 9.4% of the land was impacted by wild fires as well as planned burning.

The figures for 2018 were 4.1%, 2019 1.6% and this year, 0.1%.

A lot of “good work” was done by the Central Land Council with Aboriginal ranger groups in the “broader Tanami region”.

NEWS: Had there been not enough planned burning in the time leading up to the West Macs fires?

FISCHER: It’s reflective of the seasonal conditions. If we don’t have the successive rainfalls we don’t have the grass fuels to do that planned burning. A lot of the planned burning that Bushfires NT undertakes on behalf of land holders is within road corridors to prevent roadside ignitions or to be used as strategic lines in the case of broader fires.

NEWS: Should the buffel that drove the West Macs fires in early 2019 have been removed by planned burning six months earlier?

FISCHER: There are a few complexities with that. A lot was in these river and creek corridors with very old and well established river redgums and other native species. Buffel can burn hot year-round which adds some challenges to be able to adequately get in there and undertake that planned burning.

He says much has been learned about buffel control with work in the Todd and Charles Rivers: “A huge amount of work in a very small area.

“When we apply that to the West Macs … a massive amount of work needs to be done.”

NEWS: Can it be done? There are 600 prisoners in the Alice Springs gaol.

Aftermath of buffel fire in the West Macs.

FISCHER: It’s a good question. They have been utilised in the Todd River and the Charles and there have been good results.

NEWS: Why were they not used in the West Macs?

FISCHER: We are talking about a large difference in scale, a park that extends from Alice Springs all the way out to Mt Sonder, for people on the ground to remove grass from around these trees. That’s a longer term project. There are good outcomes from the collaboration in Alice Springs. If these opportunities [are to be] applied elsewhere, certainly we can have these conversations with Parks and Wildlife, us and the land owners.

NEWS: Are these conversations happening?

FISCHER: They are happening now and not just with Parks but with all land holders. This includes identifying critical infrastructure.

He says what drives fires is not just fuel load but also “connectivity” – one spinifex plant touching another.

Bushfire problems are caused when there are two consecutive above-average rain seasons.

NEWS: Could fire bombers have made a difference in fighting the 2019 fires?

FISCHER: We needed to make a cost-benefit analysis. What are we protecting? Where we use water bombers in the NT we have high value assets, maybe critical infrastructure, through to life and property. We use [water bombers] to give our ground crews the opportunity to get the upper hand.

NEWS: The country in the parks is a prime asset for our tourism industry. Or are we talking mostly about rangers’ houses and canteens and toilets at camping areas? 

FISCHER: We’re talking about where people are in terms of where they live, where they work. In Central Australia we don’t have water bombers that are on stand-by and ready through the fire season. The number of fire events does not warrant the contractual arrangements for water bombers on regular stand-by.

NEWS: They can be in Alice Springs in two hours.

FISCHER: If there was risk to life and we had catastrophic fire danger there would be consideration to request the utilisation of these resources. In the West Macs it was determined that it would not have provided any additional benefit in terms of protecting life and property.

NEWS: The airport in Alice Springs has high flow water supply that could fill a water bomber in about five minutes. And the airport has its own fire crew.

FISCHER: There is a huge logistical element. It’s not just putting water into a plane, a whole range of people who need to be qualified. We need rotary wing aircraft to determine where the targets are, as well as ground crews to support that, the foam and retardant supplies. Quoting two hours is not realistic in Central Australia. The closest water bombers are in Kununurra, Darwin and Adelaide.

PHOTO at top: West MacDonnells hill near Ormiston Gorge charred in West MacDonnells fire in January 2019.



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BOM declares La Nina alert, with 70pc chance of forming in 2020


The odds of a La Nina in the coming months have improved to a 70 per cent chance — roughly three times the normal likelihood — and it’s not the only climate driver that could potentially favour wet conditions heading into spring.

Bureau of Meteorology (BOM) climatologist Naomi Benger said La Nina could mean a few different things for the Australian region.

“One of them is enhanced rainfall for central, eastern and northern Australia,” she said.

“So while some areas might welcome that bit of extra rain if they’ve been in drought, it can lead to an elevated risk of flooding.”

La Nina events are also associated with heightened risk of cyclones as well as cool daytime temperatures.

“There is generally more cloud and more soil moisture, which means the daytime temperatures could be a little bit lower on average,” Dr Benger said.

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La Ninas are typically wet, but …

Weather nerds with good memories will recall a La Nina was declared in 2017 and, rather than bringing widespread rains, it was the beginning of the latest drought.

Dr Benger said that La Nina did not last long enough for the impacts to really manifest.

“The last significant La Nina event was in 2010-11, and that was Australia’s wettest two-year period on record,” she said.

When there is a La Nina, the Walker circulation intensifies, bringing wet and warm conditions to Australia.(Supplied: BOM)

Many will remember that summer for widespread flooding along the east coast, including the worst floods in Brisbane since 1974.

So are we looking at a 2017-18 or a 2010-11 kind of event?

Dr Benger said it was difficult to say at this stage, and the BOM’s announcement did not guarantee Australia will reach La Nina thresholds this year.

“At the moment there’s a 70 per cent chance of it developing, but really how it manifests will depend on the other climate drivers as well.”

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The other climate drivers

Over the past few years, the positive phase of the Indian Ocean Dipole (IOD) has been dominant, bringing dry conditions to eastern Australia.

This year, however, it looks like that could change.

“The IOD has been quite tricky this autumn-winter period to predict, but at the moment, three of the six models that the BOM surveys are indicating that a negative IOD could develop during spring,” Dr Benger said.

A negative IOD favours wetter-than-average conditions for Australia — but some of the models are indicating a more neutral IOD in the coming months.

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“We are certainly not as confident in that as we are with the La Nina,” Dr Benger said.

But at least it currently looks unlikely we will be facing another strong positive IOD.

Then, of course, there are other drivers, like the Southern Annular Mode (SAM).

Dr Benger said while the SAM operated on a shorter time period, it would affect how far north or south frontal systems to the south of Australia moved and how far south rain-bearing systems came along the east coast.

“So that will also play into when and where we get rainfall.”

Speaking of cold fronts, a series of fronts and troughs is expected to bring strong winds, rain, hail, snow and below-average temperatures for the south-east of the country over the coming days.

As usual, check the warnings with the BOM or your local ABC emergency broadcaster on Facebook or radio and heed the advice of your local emergency services.

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