Lethal Heating: 01/18/17

18/01/2017

More Rain On The Horizon As Climate Change Affects Australia, Study Finds

Fairfax - Rachel Browne

Australians will need to batten down the hatches with more intense rain storms predicted as a result of higher humidity driven by a rise in global temperatures.
New findings from the ARC Centre of Excellence for Climate System Science, published in Nature Climate Change on Tuesday, reveal that a two-degree rise in average global temperatures would lead to a 10-30 per cent increase in extreme downpours.

The state of our climate in 2016
Australia is already experiencing an increase in extreme conditions from climate change - and it's projected to get worse.

The study's authors predict that while some parts of the continent will become wetter, others will experience increasing drought.
Steve Sherwood, a professor at the Climate Change Research Centre at the University of NSW who contributed to the research, said global warming would have a clear impact on rainfall.

More heavy rainstorms are on the horizon, according to climate scientists. Photo: Dominic Lorrimer

"There is no chance that rainfall in Australia will remain the same as the climate warms," he said.
"With two degrees of global warming, Australia is stuck with either more aridity, much heavier extreme rains, or some combination of the two."
The findings come as Sydney prepares for two days of above average temperatures with a maximum of 31 degrees forecast for Tuesday and 36 degrees forecast for Wednesday. The Bureau of Meteorology is forecasting rain towards the end of the week.
The scientists examined the heaviest rainstorms across Australia, focusing on the different climates of Sydney, Melbourne and Darwin.
They found greater average humidity led to an increase in heavy downpours. Even in areas where humidity and rainfall was lower, a two degree increase in global temperature led to an 11 per cent increase in total rainfall.
The study's lead author Jiawei Bao said most parts of Australia would be affected by an increase in global temperatures.
"Extreme precipitation is projected to increase almost everywhere in Australia from tropical regions in the north to mid-latitudes in the south and from dry deserts in the centre to wet places along the coast," he said.
"Rising air temperature is the primary reason for this change. Australia's infrastructure will need to be prepared to adapt to these more extreme rainfall events even if we act to moderate the global temperature rise to within two degrees."
Australia is a signatory to the 2015 Paris Agreement, a global aim to keep average temperature increases to well below two degrees.
Professor Sherwood warned that current policies worldwide are not enough to meet the Paris targets.
The study found that a four per cent rise in global temperature, possible based on current increases in the rate of carbon emissions, would lead to a 22-60 per cent increase in extreme rain storms.
"It is likely we face even greater changes unless policies are strengthened," Professor Sherwood said. "Australia can not use past observations alone to develop rainfall infrastructure. This research tells us we need to be prepared to adapt to a world of far more intense rainfall extremes, if we can."

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Epic Antarctic Voyage Maps Seafloor To Predict Ocean Rise As Glacier The Size Of California Melts

The Guardian - Calla Wahlquist

Global research group will trace Totten glacier’s history back to last ice age, in hope of predicting future melting patterns

The Totten glacier is under threat from warming ocean temperatures, scientists say, and a team has left for the Antarctic region on a research voyage. Photograph: Department of Environment/AAP

In East Antarctica, 3,000km south of the West Australian town of Albany, an ice shelf the size of California is melting from below.
The concerning trend was confirmed by Australian scientists in December, who reported that warming ocean temperatures were causing the rapid melt of the end of the Totten glacier, which is holding back enough ice to create a global sea rise of between 3.5 metres and six metres.
On Saturday, a team of international scientists left Hobart aboard the Australian research ship Investigator to map the seafloor ahead of the glacier to trace its history back to the last ice age, in the hopes of predicting its future melting patterns.
The 51-day mission is one of the longest ever voyages by Australian scientists to Antarctica and will involve mapping the unexplored Sabrina Coast seafloor and taking samples of piles of glacial sediment left behind by the retreating ice sheet.
It has been four years in the planning for the chief scientist Dr Leanne Armand, an associate professor with Sydney’s Macquarie University.
The focus will be the area around the base of the Totten glacier, which is usually surrounded by ice. Reports from researchers aboard the Aurora Australis, which was in the area in December, show that fast ice has melted back.
“If that goes, then we’ll be able to get in and provide the very first seafloor maps on the continental shelf itself and that will be really critical to a whole bunch of different sciences,” Armand said.
She will head a team of 22 researchers from Australia, Italy, Spain and the United States. They will be assisted by 12 support staff from the Marine National Facility, a subdivision of the CSIRO, which operates the Investigator; a Tasmanian high school science teacher; and 20 crew.
Also on board is Dr Tara Martin, a CSIRO scientist who helped design the Investigator and will act on this mission as the ship’s geophysicist, monitoring the sonar and seismic equipment used to map the seafloor.
Martin said the seismic equipment, borrowed from the Istituto Nazionale di Oceanografia in Italy, would be used to examine the composition of the sediment layers to help researchers pinpoint the best locations for extracting rock cores, which will in turn be used to map past glacial melting patterns.
“One of the things we’re trying to understand here is, is this [glacial] retreat normal, has this kind of retreat happened before, and has this speed of retreat happened before,” Martin said. “If it’s not normal, how much of what we’re observing today can we isolate from what is normal, and therefore maybe see what could be an anthropogenic effect.”
The worst scenario, Martin said, was that the ice tongue of the glacier could disappear.
“If you remove that ice tongue, in theory you’re releasing the break on the rate of flow of the glacier,” she said. “So the concern is ... if the whole ice tongue melts away, potentially the whole glacier could rush out to sea over a geological timescale, and we don’t know what that timescale is. Losing an ice tongue and having it break off – it’s already in the water, that doesn’t add to sea level rise very much. But losing a glacier the size of California that’s currently on land and dumping that in the water – that’s going to change sea level rise estimates.”
The expedition is authorised to take a maximum of 15 cores, measuring 10cm in diameter and up to 24 metres long.
The cores will be cut into one metre lengths in an area known as the “wet and dirty lab”, capped at both ends, and placed in cold storage until they can be transported to Geoscience Australia, where interested researchers will hold a party to divide up the samples.
It is Armand’s ninth voyage to the Antarctic, and Martin’s 14th. Both have refined their list of items to bring to stave off boredom on the lengthy voyage, in the little downtime provided at the end of a 12-hour shift.
The ship is kitted out with a gym, a video and games room, and twin bunk rooms with en suites, as well as sophisticated scientific equipment and laboratories.
The bunk beds have curtains to help roommates on opposite shifts.
But even in those comparatively comfortable environments, Armand says, most people bring some form of creature comfort.
Armand’s must-have is natural raspberry cordial, followed by a box of her favourite muesli and her own mug. Martin’s is more extensive: a “a seriously embarrassing amount of books,” as well as a camera, binoculars and field guide for spotting wildlife. She also brings knitting.
Her list of books is eclectic: Dickens, Austen, a few popular science geology books recommended to her by a “geeked out” pack of geoscientists on her last sub-Antarctic voyage, the memoirs of Philip Law, who directed the Australian Antarctic Division in the 1950s, and a “standard range of fiction”.
On top of personal luxuries, and Martin’s small library, everyone on board is required to bring, at minimum: two pairs of gloves (one waterproof, one woollen); one beanie; two pairs of woollen or thermal pants, two woollen or thermal tops, three pairs of woollen socks; one polar fleece jacket; one pair of polar fleece pants; one pair of steel-toe boots; and one pair of polarised sunglasses.
A strap for said sunglasses, a balaclava, a snood, an insulated down jacket, and steel-toe gumboots are highly recommended.
Other safety gear, such as hard hats and high-visibility jackets, is provided.

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Koalas Are At The Centre Of A Perfect Storm. The Species Is Slipping Away

The Guardian - Kevin Evans

Australia is one of the worst performing countries in terms of protecting its ecoregions. Koalas are a litmus test for conservation of a habitat in crisis

‘As you may expect from a species inhabiting a crisis ecoregion, the koala is not faring so well.’ Photograph: Alamy Stock Photo

In 2016 koalas were sighted for the first time in decades at Mount Kembla, Wollongong and in Kosciuszko national park in New South Wales. Although these sightings are a source of hope, it’s important we don’t get lulled into a false sense of security about the extent to which nature, including koalas, is threatened in Australia. We have serious work to do to protect our unique plants and animals.
Most environment news these days focuses on climate change. In many ways this isn’t surprising. Climate change threatens to alter our entire environment as rainfall patterns change, temperatures rise and extremes become more common. Many species are already finding their habitats shrinking – just look at polar bears and the rapidly vanishing Arctic sea ice.
Yet amid this climate emergency “mere” species extinctions have largely been pushed out of mind. Of course the issues are intertwined as climate change can cause extinctions: in July the Bramble Cay melomys (a rodent) was reported as the first animal to have been made extinct primarily due to climate change. In its case, its single-island habitat had been repeatedly inundated by rising sea levels destroying the native vegetation and ultimately the species itself. And of course climate change threatens to exacerbate and amplify other threats to species like bushfires and heatwaves.
But human destruction of habitat is, at least in the short term, a much greater threat to species than climate change. In mid-December, scientists from the University of Queensland were part of a team that found, of all developed countries on Earth, Australia was performing worst in protecting its ecoregions (areas containing broadly similar habitat). The researchers identified “crisis ecoregions” where habitat loss is greatest. A crisis ecoregion in Australia? Temperate forests.
Enter the koala. Undoubtedly the most famous inhabitant of Australian temperate forest ecosystems, and arguably the world’s favourite species. But as you may expect from a species inhabiting a crisis ecoregion, it’s not faring so well. Historical accounts describe large numbers of koalas being seen regularly in the late 1800s in NSW. In 1921, 200,000 koala pelts passed through Sydney and in 1924 two million pelts were exported from eastern Australia.
Yet now all koala populations, bar a few in eastern Australia, are in decline. Some sharply so. So whether or not you find, as we do, the most recent estimate of 329,000 in Australia (36,000 koalas in NSW) to be optimistic one thing is clear: koala numbers are a fraction of what they once were and the species is slipping away.
In NSW, koalas are in the centre of a perfect storm largely of the government’s own making: changes to land clearing laws have already devastated bushland in Queensland and history threatens to repeat itself in NSW with the Baird government recently passing its land-clearing legislation.
Much remaining high-quality koala habitat is either on private land, thus at risk of clearing, or in state forests and thus subject to ever more intense state-sanctioned logging. Urban development is eating into koala habitat up and down the coast. And following this habitat destruction, koalas are vulnerable to dog attacks and vehicle strike as they spend more time on the ground.
If this were happening to a snail, or even a frog, it would probably be ignored. But koalas are one of the few animals whose plight the government finds it hard to ignore. That’s why the NSW government is currently beginning the development of a whole of government koala strategy and asking for community feedback on planning issues and its Saving Our Species conservation strategy. At a federal level, the National Koala Conservation and Management Strategy expired in 2014. Word is that a new strategy is in the pipeline but at the moment we’re flying blind.
The best way to protect koalas is a tried and tested one. The scientists that identified the crisis ecoregion problem also identified the solution: large, well-connected protected areas. Only by protecting and connecting remaining koala habitat can the government enact meaningful conservation. Everything else is tinkering round the edges.
And only by demonstrating that it can effectively protect koalas can we have any confidence that the government can protect the rest of Australia’s extraordinary wildlife that doesn’t share the koala’s high profile.

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