13/04/2017

Northern NSW Is No Stranger To Floods, But This One Was Different

The Conversation - 

Lismore received a drenching from the tail end of Tropical Cyclone Debbie. AAP Image/Dave Hunt
The devastating flood damage wreaked by Tropical Cyclone Debbie has left many residents in northern New South Wales facing an enormous cleanup that could take months.
Any Lismore local will tell you that flooding is a fact of life in the Northern Rivers. In the floods of 1954 and 1974, the Wilsons River rose to a record 12.17 metres. This time around, the river peaked at 11.59m, breaching the flood levee built in 2005 for the first time.
So what are the conditions that caused those historic floods? And are they any different to the conditions of 2017?
Like the current flood, cyclonic rains also caused the 1954 and 1974 events. But unlike those past events, both of which were preceded by prolonged wet weather, almost all of the extreme rainfall from ex-Tropical Cyclone Debbie fell within 24 hours.
More interesting still is the fact that we are not currently experiencing La Niña conditions, which have historically formed the backdrop to severe flooding in eastern Australia.
The 1974 mark still stands as Lismore’s record. Ricky Lewis, Author provided
The 1954 flood was preceded by an east coast low from February 9-11, followed by a decaying tropical cyclone from February 19-22. Thirty people were killed as flood records were set in Lismore, Kyogle, Casino, Nimbin and Murwillumbah. Some places received more than 1,000mm of rain in 14 days.
In 1974, former Tropical Cyclone Zoe unleashed torrential rain over Lismore, Wyrallah and Coraki. From March 10-13, some stations received almost 1,000mm in just four days. One analysis described the flood as a once-in-70-year event.
This time around, the remains of Tropical Cyclone Debbie delivered extreme rainfall to northern NSW towns including Murwillumbah, Chinderah and Lismore, despite having crossed the coast several days earlier and more than 1,200km to the north. Floods as far apart as Rockhampton in central Queensland and northern New Zealand show the storm’s colossal area of influence.
During the event, 20 rainfall stations in Queensland and 11 sites in NSW recorded their wettest March day on record. Mullumbimby, in the Brunswick River catchment, received a staggering 925mm during March – over half the annual average in a single month – causing major flooding in the region.
The heaviest rainfall in the Wilsons River catchment was at Terania Creek, which received 627mm over March 30-31, 99% of it in the 24 hours from 3am on March 30. Lismore recorded 324.8mm of rain in the 18 hours to 3am on March 31, its wettest March day in more than 100 years. A little further out of town, floodwaters submerged the gauge at Lismore Airport, so unfortunately we do not have reliable figures for that site.
March 2017 rainfall across Australia. Tropical Cyclone Debbie’s track down the east coast is visible in the trail of above-average falls. Bureau of Meteorology
 The main difference between the current flooding and the 1954 and 1974 floods is that the previous events both occurred against a background of sustained La Niña conditions. These tend to deliver above-average tropical cyclone activity and high rainfall totals, which increase flood risk.
During the early 1970s, Australia experienced the longest period of La Niña conditions in the instrumental record. This unleashed phenomenal deluges across virtually the entire country. By the end of 1973, many catchments were already saturated as the wet season started early, culminating in the wettest January in Australia’s rainfall records.
In 1974 the Indian Ocean was also unusually warm (what meteorologists call a “negative Indian Ocean Dipole (IOD) phase”), further enhancing rainfall in the region. When negative IOD events coincide with La Niña conditions in the tropical Pacific, the warm sea temperatures reinforce one another, resulting in more evaporation and increased rainfall. This double whammy resulted in the exceptionally wet conditions experienced across the country during 1974.
In January 1974, the Northern Territory, Queensland and Australia as a whole recorded their wettest month on record, while South Australia and New South Wales recorded their second-wettest January on record. Torrential monsoon rains in the gulf country of Queensland transformed the normally dry interior into vast inland seas, flooding all the way to Lake Eyre in the arid zone of South Australia.
Vast swathes of Australia were much wetter than average during the mid-1970s. Bureau of Meteorology
In contrast, Tropical Cyclone Debbie formed under neutral conditions, rather than during a La Niña. In fact, the Bureau of Meteorology is currently on El Niño watch, meaning that there is double the normal risk of an El Niño event bringing low rainfall and high temperatures to Australia by mid-2017.
So, unlike the 1950s and 1970s, the current flooding happened despite the absence of conditions that have driven major flooding in the past. It seems extraordinary that such a damaging cyclone could develop under these circumstances, and deliver such high rainfall over such a short time. This suggests that other factors may be at play.
A rapidly warming climate means that storms are now occurring in a “super-charged” atmosphere. As temperatures increase, so does the water-holding capacity of the lower atmosphere. The oceans are also warming, especially at the surface, driving up evaporation rates. Global average surface temperature has already risen by about 1℃ above pre-industrial levels, leading to an increase of 7% in the amount of water vapour in the atmosphere.
Ocean evaporation, before and after ocean warming. Climate Council
Of course, it is hard to determine the exact impact of climate change on individual storms. However, climate scientists are confident about the overall trends.
Australia’s land and oceans have warmed by 1℃ since 1910, with much of this warming occurring since 1970. This influences the background conditions under which both extremes of the rainfall cycle will operate as the planet continues to warm. We have high confidence that the warming trend will increase the intensity of extreme rainfall experienced in eastern Australia, including southeast Queensland and northern NSW.
While it will take more time to determine the exact factors that led to the extreme flooding witnessed in March 2017, we cannot rule out the role of climate change as a possible contributing factor.
CSIRO’s latest climate change projections predict that in a hotter climate we will experience intense dry spells interspersed with periods of increasingly extreme rainfall over much of Australia. Tropical cyclones are projected to be less frequent but more intense on average.
That potentially means longer and more severe droughts, followed by deluges capable of washing away houses, roads and crops. Tropical Cyclone Debbie’s formation after the exceptionally hot summer of 2016-2017 may well be a perfect case in point, and an ominous sign of things to come.

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Adani Firms On $1bn Loan As Turnbull Promises To 'Fix' Native Title Problems

AFR - Phillip Coorey


Turnbull to fix native title for Adani

Indian billionaire Gautam Adani has told Malcolm Turnbull his company will seek a taxpayer-funded concessional loan of up to $1 billion to support his proposed $21.7 billion coal mine in Queensland.
And the Prime Minister has assured him the native title hurdles threatening the project will be "fixed".
Following a meeting with Mr Adani and his executives in New Delhi on Monday night, Mr Turnbull cautioned the loan – to help build a $2 billion railway line to link the mine to the coast – would have to be approved on its commercial merits by the independent board which administers the $5 billion Northern Australia Infrastructure Fund.
"They are enthusiastic to make an application to the NAIF," Mr Turnbull said. "It will be assessed scrupulously independently." He said the loan may not be enough to guarantee the whole project and it was up to Mr Adani to satisfy the project's commercial challenges.
But Deputy Prime Minister and Nationals leader Barnaby Joyce argued the loan should be approved, saying it was "a tipping point issue" as to whether the mine went ahead.
"I know the greenies will go off their heads … but I can deal with that," Mr Joyce said.
Labor leader Bill Shorten re-emphasised his opposition to giving the company a loan, saying the entire project should rest on its commercial merits. He also said it would be unfair to other companies in Australia. "Other mining companies are not getting billion-dollar railways built for them. I'm not convinced that the taxpayer of Australia should underwrite the risk of the project," Mr Shorten said.

Stuck in Senate
During the meeting on Monday, Mr Adani expressed concern at a Federal Court decision in February on native title which has threatened the giant coal mine as well as 125 other developments.
The government moved swiftly by introducing legislation – with the initial support of Labor – to overturn the decision, but it has become stuck in the Senate. Mr Turnbull said "the issue needs to be fixed and will be fixed" when Parliament resumes in May.
The legislation seeks to overturn the McGlade decision that upheld the Native Title Act requirement that all traditional owners are needed to sign an Indigenous land use agreement or the agreement is invalid.
The decision related to a claim in Western Australia but put in doubt 126 projects nationwide, including Adani's Carmichael mine. Soon after, members of the Wangan and Jagalingou clans lodged documents in the Federal Court in Brisbane challenging claims Adani had the consent of all traditional owners to proceed with the mine.
The legislation never passed Parliament because it would make permanent the changes to the Native Title Act whereas Labor wanted it only to specifically address the 126 projects affected. Mr Turnbull said he would adjust the legislation to satisfy Labor and protect the Adani project.
But over time, the government would press the Senate crossbench to support the broader changes.
"It's a decision that can't be allowed in practical terms to let stand," Mr Turnbull said. "We can advance the other amendments at a later date."
The Adani proposal is enormously controversial with environmental groups but Mr Turnbull said it was economically vital. "Plainly there's a huge economic benefit from a project of this kind," he said. "This project, if it's built, will create tens of thousands of jobs."
Mr Turnbull left for Mumbai on Tuesday night where the focus switched to trade and energy.

Key areas of disagreement
In a business speech, he announced the formation of the India Economic Strategy, led by former senior diplomat Peter Varghese, to try to exploit the economic relationship with India as plans for a free trade deal falter.
Mr Turnbull and his Indian counterpart, Narendra Modi, have attempted to breathe life into the FTA by commissioning senior officials to hold talks and identify the key areas of disagreement. For India, that is agriculture, for Australia it is labour mobility.
But the India Economic Strategy is a different approach to the FTA.
"The strategy will look beyond the immediate horizon. It will provide a plan to unlock the opportunities that will help us grow together, with a map that will guide our partnership through to 2035," Mr Turnbull said.
"It is not about Australia 'discovering India' but cementing India as a priority economic partner. "It will explore how to strengthen existing economic collaboration, whilst identifying new ways to do business together.
"It will identify how Australia's extensive reform experience can best support India's economic reform agenda and modernisation."
And it will recommend new ways to maximise mutual benefits, including by engaging at the sub-national level – many Indian states have globally significant economies in their own right, Mr Turnbull said.

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Loss Of Coral Reefs Caused By Rising Sea Temperatures Could Cost $1tn Globally

The Guardian -  | 

Devastation of world's coral reefs could cost $1tn

The loss of coral reefs caused by rising sea temperatures could cost $1 trillion globally, a report from Australia’s Climate Council has projected, with the loss of Queensland’s Great Barrier Reef alone costing that region 1m visitors a year, imperilling 10,000 jobs and draining $1bn from the economy.
The longest global coral bleaching event on record, which began in 2014 and has affected some reefs in consecutive years, has given reefs little chance to recover, and should be a “wake-up call” to act to save the natural and economic assets, the Climate Council’s Lesley Hughes said.
“The extraordinary devastation being experienced on the Great Barrier Reef is due to the warming of our oceans, driven by the burning of coal, oil and gas,” Hughes said. “It would have been virtually impossible for this to have occurred without climate change.”
Hughes argued it was a false dichotomy in public debate “to pit the environment against the economy”.
“This isn’t just an environmental issue. The Great Barrier Reef is one of Australia’s greatest economic assets. It’s responsible for bringing in more than $7bn each year to our economy, while also supporting the livelihoods of around 70,000 people. A healthy Great Barrier Reef underpins the tourism industry and the jobs that it supports.”
The $1 trillion figure for the value of the world’s coral reefs is derived from a 2015 report led by Ove Hoegh-Guldberg, director of the University of Queensland’s Global Change Institute, which found that worldwide, reefs supported 500 million people across 50 nations.
The cooler water temperatures brought by Cyclone Debbie are expected to offer Queensland reefs some relief from the bleaching events of 2016 and 2017, though this is expected to be only temporary, and could be offset by the physical damage caused by the Category 4 tropical cyclone.
Professor Will Steffen, climate councillor and emeritus professor at the ANU, said bleaching events were likely to become more frequent and more severe in Australia over the next two to three decades, which could devastate the long-term health of the reef and its ability to regenerate.
“The only way to protect coral reefs in Australia and around the world is to stop greenhouse gas emissions. Australia is the caretaker of the Great Barrier Reef and we are lagging well behind the rest of the developed world when it comes to doing our part to effectively combat climate change.
“Emissions are flatlining in China and declining in the United States and in other OECD countries. In comparison, Australia’s emissions continue to grow. We’ve got to stop and then reverse this trend and we’ve got to do it now. There is no time to lose.”
Australian emissions grew by 0.8% in 2016, the council’s report says.
Steffen said the opening of new coalmines in Queensland’s Galilee Basin was inconsistent with protecting the Great Barrier reef, and reducing Australian – and global – carbon emissions.
This week the Australian Research Council’s centre of excellence for coral reef studies released the results of its latest aerial surveys, which assessed 800 individual reefs.
The surveys show the 2016 and 2017 mass bleaching events have now affected two-thirds of the reef. Only the reef’s southern third has emerged unscathed. This year’s bleaching event was most intense in the reef’s middle third, while last year’s was further north.
The federal and state governments’ efforts to save the reef have been laid out in a joint long-term plan through to 2050. Combined, they spend about $200m annually to protect and preserve the reef.
Announcing new measures last month – including offering financial incentives to farmers who reduce nitrogen and sediment run-off into the reef – environment minister Josh Frydenberg said the government was working with local communities to improve the reef’s health and maintain it for future generations.
“These new projects complement existing efforts and demonstrate how we can make private investment work effectively alongside public funding to maximise results for the reef from each dollar invested. Collaborative partnerships like the ones announced today are critical to address the threats and pressures faced by the reef.”
Both the federal and state governments support Indian conglomerate Adani’s proposed Carmichael coalmine in the Galilee Basin in central Queensland, which environmental groups and climate scientists have argued will cause massive carbon emissions, and endanger local species and groundwater supplies.

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