03/07/2021

(AU SMH) From Drying Rainforests To Heavier Downpours, Australia’s Climate Is Changing

Sydney Morning Herald - Peter Hannam

Australia’s tropical rainforests will dry out, marine and land heatwaves will become more frequent and intense, and thunderstorms will dump more rain and worsen floods as the globe heats up.

These are among the many impacts from climate change that will blight the nation further unless atmospheric levels of greenhouse gases stabilise, according to the final report of the federal government’s Earth Systems and Climate Change Hub.

’Hub research has shown a clear link between climate change and worsening bushfire weather conditions over the past 70 years,” the centre’s final report finds. Credit: Nick Moir

The work of more than 100 researchers, to be expanded in a new Climate Systems Hub that began operations on Thursday, made advances across fields ranging from bushfire prediction to the rapid identification of the role climate change rather than natural variability plays in an extreme weather.

“It’s clear that climate change is already happening and having impacts,” said David Karoly, the leader of the Earth Systems Hub that ended its work on June 30.

Hub achievements include the “massively successful” improvements to the main ACCESS climate model used by Australian governments and agencies to hone future predictions to a smaller scale than before, he said.

Ancient Gondwanan rainforests in Queensland and NSW, which get as much as 40 per cent of their moisture from being shrouded in clouds, face a drier and hotter future with climate change. Credit: Brian Cassey
The final report said there was “a clear link between climate change and worsening bushfire weather conditions over the past 70 years”, and singled out the World Heritage-listed Gondwana Rainforests as one area of concern.

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The forests, which stretch from north of Newcastle in NSW up to southern Queensland, were hard hit by the 2019-20 Black Summer bushfires and are likely to become drier as clouds and fog that provide as much as 40 per cent of moisture rise in a warmer climate.

“Higher cloud height, especially during the dry season, could lead to a dry climate that is beyond the tolerance of some species, resulting in rainforest community changes,” the report found, adding “even moderate increases in cloud height were found to have significant implications for cloud-water dependent species”.

Professor Karoly said that, while the lineage of the forests dates back many millions of years, changes were underway in a matter of a hundred years, far faster than species could adapt.

Similarly rapid changes were underway in the oceans around Australia although their remoteness from most people’s experiences meant they were not well known.

The Tasman Sea is warming at four times the global average, placing at risk giant kelp forests off the Tasmanian coast. Credit: Craig Sanderson

The Tasman Sea, for instance, is warming four times faster than the global average in part because the East Australian Current is strengthening and dragging tropical water much further south.

Key ecosystems, such as the giant kelp forests off Tasmania, are at risk from more frequent heatwaves.

“A marine heatwave [in the Tasman Sea] similar in intensity to those in 2015–16 and 2017–18 is currently expected to occur approximately once every 20 years,” the report said.

“Under [a global] low-emissions scenario, it is expected to occur once every 15 years by the end of the century, and under the high-emissions scenario, a marine heatwave is projected to occur almost every year.”

Marine heatwave days per year
Source: The Earth Systems and Climate Change Hub

Thunderstorms were another area of interest, including how the number of danger so-called “pyrocumulonimbus” clouds formed out of bushfire plumes.

At least 35 of them were detected during Black Summer, increasing the risk of erratic winds on unpredictable fire behaviour and ignite new blazes ahead of the fire front, the report noted.

Cumulative observed number of fire-generated thunderstorms
Source: The Earth Systems and Climate Change Hub

East coast lows, another big weather event affecting coastal areas from Queensland to Victoria, were among phenomenon undergoing change.

The Hub developed new ways to analyse the complex storms and found the most extreme rainfall near eastern Australia was frequently caused by such low-pressure systems combining with a front and a thunderstorm.

The researchers found short-duration events produced by thunderstorms could potentially increase in intensity by about 15 per cent per degree of global warming.

A line of storms associated with an east coast low sweeping over the Hawkesbury River north of Sydney in July 2020. Credit: Nick Moir

Andy Pitman, head of the ARC Centre of Excellence for Climate Extremes and a Hub advisor, said east coast lows were “one of the least effectively studied phenomena in Australia” even though their impacts can be huge in terms of floods, storm surges and wind damage.

“I worry about how ill-prepared we are for any climate signal for east coast lows,” he said.

Drone vision of Lake Burrendong in the central-west region of NSW in January 2020 when water levels fell to a couple of per cent of capacity. Credit: Nick Moir

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At the other end of the weather spectrum was so-called flash droughts, another of the Hub’s research areas.

These are triggered by lower-than-average rainfall, accompanied by abnormally high temperatures, a dry atmosphere, clear skies and more sunshine, and can be perilous for crops.

The researchers showed the sudden dry spells could be forecast, and they can happen even in winter.

The outgoing Hub cost $23.4 million, with matching contributions from CSIRO, the Bureau of Meteorology and five universities including the University of Melbourne and the University of NSW.

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Its successor has been allocated federal funding of $38 million over six years.       

While welcomed, “we are not investing remotely enough given the scale of the risk”, Professor Pitman said, adding the new funding was “not even one year’s salary of a top soccer player”.

Simon Marsland, a CSIRO senior scientist who will lead the new Climate Systems Hub, said how communities could adapt to the warming impacts still to come will be one priority as will efforts to work closely with Indigenous populations that are often particularly exposed to extreme weather.

Dr Marsland noted the current record-shattering heatwave in Canada, with near 50-degree temperatures recorded even at a latitude as far as 50 degrees north, were “a good reminder that climate change is here now and not something in the far future”.

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(CA CBC) Western Canada's Heat Wave Is 'Unprecedented.' Scientists Say It Will Become More Common With Climate Change

CBC News - Alex Migdal

'There's going to continue being new normals until we stop emitting greenhouse gases,' says climate scientist

A woman wipes her face after cooling off in the water at a temporary misting station in Vancouver's Downtown Eastside on Monday. (Darryl Dyck/The Canadian Press)

Smoky skies. Polluted air. Sweltering heat. 

During three of the past five summers, British Columbians have endured extreme weather events, rewriting a season long known for its mild, sunny forecasts. 

This week's historic heat wave, which unleashed punishing temperatures on the Pacific Northwest and is now moving eastward to Alberta, has brought the realities of climate change into even sharper relief.

Climate scientists are cautious about citing climate change as the cause of any specific weather event. But some say evidence suggests extreme events are intensifying and becoming more common because of global warming.

"I'm shocked by this," said Simon Donner, a professor of climatology at the University of British Columbia. 

"As a climate scientist, we expect to see more extreme heat waves going forward into the future because we're adding greenhouse gases to the atmosphere. But this is even beyond my expectations. To have a heat wave last this long and be this hot in Canada is completely unprecedented in history."

'It really feels like dangerous heat'

The village of Lytton in B.C.'s Interior shattered Canada's all-time weather record over three consecutive days, surpassing an eye-popping 49 C on Tuesday. B.C.s Fraser Valley recorded temperatures in the mid 40s. Vancouver, which usually benefits from cool ocean air, recorded an overnight low of 24 C on Monday night, the type of heat often felt in the tropics. 

"There's something that feels a bit different about this one and I can't quite put my finger on it," said Joseph Shea, a professor of environmental geomatics at the University of Northern British Columbia.

"I was trying to come up with a word on the weekend and I think the word is menacing. It really feels like dangerous heat."

The 'heat dome' explained
David Phillips, senior climatologist for Environment Canada, says the high-pressure heat dome over parts of Western Canada creates an effect that's like 'putting a lid on boiling water.' 3:52

The global temperature has increased by 1.2 C since industrialization, according to the World Meteorological Organization.

A 2019 report commissioned by Environment and Climate Change Canada found Canada is warming twice as fast, with the highest rates occurring in the North, the Prairies and northern British Columbia. And temperatures in the Arctic are increasing three times the global rate. 

"That doesn't sound like very much, but it shifts the whole system. And so when you get big spikes, they get higher," said Deborah Harford, executive director of Adaptation to Climate Change, a policy planning initiative at Simon Fraser University. 

CBC metereologist Johanna Wagstaffe said jet streams — which essentially move weather patterns — are stalling much longer due to the shrinking temperature difference between the Arctic and mid-latitudes. 

"You get great waves, like what's happening over B.C., that stick around for longer," she said.
 
B.C. vulnerable to extreme weather

 The heat wave has also underscored how British Columbians have yet to adapt to the changing climate conditions and are vulnerable to its impacts.

Roughly one-third of B.C. residents use air conditioning, according to a B.C. Hydro survey from last year, with the number jumping to 72 per cent in the southern Interior. 

The heat wave, which came with only days of warning, saw stores in B.C. sell out of air conditioners and fans. Hotels in Vancouver were fully booked Monday, drawing locals desperate for escape. Police in Metro Vancouver said Tuesday they had responded to more than 100 sudden deaths since the heat wave took hold. 
  
Vancouver doctor explains what he's seeing during the heat wave
Vancouver emergency room physician Dr. Daniel Kalla on the precautions, warning signs and potential remedies for heat-related illnesses as temperatures reach record highs, and how to cool down. 2:26

Record overnight temperatures made matters worse, with a low of 22 C in Victoria on Monday — close to the typical daytime high for that time of year. 

"We need those evenings to recover from the hot days that we experience," said Faron Anslow, a climatologist with the Pacific Climate Impacts Consortium in Victoria. 

While the heat wave was unusual in its intensity, Wagstaffe anticipates B.C.'s baseline will shift in the coming years. 

"We'll see more days, over 30 degrees. We'll see way more days, over 20 degrees," she said.

"And we'll really start to notice a change in our seasons. We'll see the extreme weather events l

ike fires and severe storms and flooding start earlier and last later." 

Mountaintops that never melt are thawing as a result of the heat wave, Wagstaffe said, raising questions about flood risk and the impact on water reserves through the summer and into the early fall. 

The wildfire risk also looms large. Forests are drying out and are rapidly turning into tinder for when a lightning storm strikes or a cigarette is tossed. 

"I think we've all learned in the past few years, the forest fire doesn't have to be anywhere near your home for you to be affected by it," Donner said.

What next?

While British Columbians have grown accustomed to wildfires, the severity of the heat wave has renewed awareness around the climate emergency. 

"I've covered a lot of weather events that have been connected to climate change," Wagstaffe said. 

"And I've got to be honest, I think this one is the one that really made me consider my future and my two-year-old's future. We were literally trying to think of an emergency plan for the forecast that had heat that would be too dangerous for my family to be in our own home." 

Shea said the only way to stop climate change is to stop pumping emissions into the atmosphere. 

"It's simple to say that but very hard to do because of the systems we have in place," he said. "At this point, there's nothing else we can do except really make that push." 

The Paris climate agreement aims to keep the global temperature increases this century below 2 C — and ideally 1.5 C — to stave off the worst effects of climate change.

A construction worker uses a misting fan to cool down at a work site in Vancouver on Monday. Vancouver police say they have responded to more than 100 sudden deaths since the heat wave took hold. (Ben Nelms/CBC)
Anslow said change on a personal level can mean reducing your emissions by curtailing vehicle use, reconsidering what you eat and cutting down on energy use at home. 

"These all will seem like pretty small drops in the bucket when you're doing them, but they do add up," he said. 

Donner said people need to push their politicians for stronger action, such as regulations around electric vehicles and energy-efficient homes and buildings.

"This is not the new normal," Donner said.

"There's going to continue being new normals until we stop emitting greenhouse gases because the baseline, or what we think of as normal, is constantly moving upwards now." 

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(AU The Guardian) Australia Ranks Last For Climate Action Among UN Member Countries

The Guardian - 

Nation scores just 10 out of 100 on tackling fossil fuel emissions in new report on sustainable development goals
The Loy Yang Power Station in Traralgon, Victoria. A UN-backed report has ranked Australia last on climate action. Photograph: David Gray/Getty Images
Australia has been ranked last for climate action out of nearly 200 countries in a report assessing progress towards global sustainable development goals. The Sustainable Development Report 2021, first reported by Renew Economy, scored Australia last out of 193 United Nations member countries for action taken to reduce global greenhouse gas emissions.

A database shows Australia received a score of just 10 out of 100 in an assessment of fossil fuel emissions, emissions associated with imports and exports, and policies for pricing carbon.

Second last was Brunei, which was ranked behind Qatar and Norway.

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Richie Merzian, a climate expert at the Australia Institute, said the result was unsurprising.

“Australia has received similar rankings from other comparable studies, including the Climate Change Performance Index, which last year ranked Australia second last behind only Trump’s America,” he said.

“The federal government has no climate and energy policy and instead has cherry-picked technologies, many of which support the fossil fuel industry.”

The report noted Australia had not committed to achieving netzero carbon emissions by 2050. Scott Morrison has instead signalled Australia wants to achieve carbon neutrality as soon as possible and “preferably” by 2050.

The most recent emissions data, released by the government in late May, showed Australia’s greenhouse gas emissions were at the lowest levels in 30 years as the coronavirus pandemic put a handbrake on fossil fuel burning in the transport sector and slowed economic activity.

In a statement at the time, the energy minister, Angus Taylor, said those levels were despite “upward pressure from growth in exports and industry”.

The Sustainable Development Report tracks countries’ progress towards the UN’s 17 sustainable development goals, which include quality education, gender equality, wiping out poverty, creating sustainable cities and communities, and affordable and clean energy.

Australia ranked 35th overall, performing strongly on health and wellbeing, economic growth, education and clean water and sanitation.

For clean energy, Australia was listed as having “major challenges” but recorded a moderate improvement over the past 12 months.

The report says countries should not allow the Covid-19 pandemic to lead to a prolonged reversal in progress towards the goals.

“International commitments, for instance towards climate neutrality, must be rapidly accompanied by transformative actions and investments,” the report says.

“Large fiscal packages of major economies present an opportunity to foster a green, digital, and inclusive recovery.”

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