02/11/2019

The Science Of Drought Is Complex But The Message On Climate Change Is Clear

The Conversation - Ben Henley | Andrew King | Anna Ukkola | Murray Peel | Q J Wang | Rory Nathan


Detecting human fingerprints on complex events like droughts is not straightforward. AAP Image/Dan Peled
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.

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.
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.
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.

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Six Biggest Coalminers In Australia Produce More Emissions Than Entire Economy

The Guardian - 

Big emitting companies should be held responsible for the burning of their coal overseas, report says
The top six coal producers were linked to 551m tonnes of carbon dioxide released into the atmosphere in 2018. Total emissions from all activity in Australia were 534m tonnes. Photograph: Dave Hunt/AAP 
Coalmining in Australia by the nation’s six biggest coal producers ultimately results in more greenhouse gas emissions each year than the entire domestic economy.
In the latest report to estimate the role fossil fuel businesses play in driving the climate crisis, researchers from the University of New South Wales calculated the total emissions from the coal and gas produced by Australia’s top carbon companies, from extraction to the resources being burned for energy, mostly overseas.
They found the top six coal producers – BHP Billiton, Glencore, Yancoal, Peabody, Anglo American and Whitehaven – were in 2018 linked to 551m tonnes of carbon dioxide released into the atmosphere. Total emissions from all activity within Australia were 534m tonnes.
When the list was expanded to include Australia’s 10 biggest carbon producers, adding Chevron, Woodside, ExxonMobil and Santos, the combined emissions from their products was found to be 670m tonnes a year, equivalent to that from about 75% of global air traffic.
Australia's carbon majors and GHG emissions 2018
Coal in red, oil and gas in orange
Emissions in Mt CO2-e
Guardian graphic
The UNSW report follows the Guardian’s global series The Polluters, which revealed 20 fossil fuel companies including BHP could be directly linked to more than one-third of all greenhouse gas emissions in the modern era. In Australia, it found a wave of planned developments by major fossil fuel companies across the north would significantly increase the amount of coal and gas the country planned to sell into Asia and could push the Paris climate agreement goals further beyond reach.
The report’s lead author, Jeremy Moss from the UNSW Practical Justice Initiative and a professor of political philosophy, said there was a clear case that big emitting companies, which the report calls “carbon majors”, should be held responsible for the consequences of their products.
Global greenhouse accounting emphasises national emissions, rather than those connected to companies. There are no plans for that to change. But there is an increasing focus within companies in reporting and considering how to deal with “scope 3” emissions, including those that are released by a company’s customers when using their products.
BHP’s chief executive, Andrew Mackenzie, acknowledged this in July when, in a speech calling for drastic action to combat the climate crisis, he pledged US$400m to develop technologies to cut emissions from not only its own operations, but also the companies that buy its resources. BHP, Rio Tinto and South 32 are among those that report scope 3 emissions.
Moss said fossil fuel companies had a moral responsibility to rapidly phase out their operations in line with the evidence of the Intergovernmental Panel on Climate Change, which found global emissions need to fall 45% below 2010 levels by 2030. He said companies should retire assets, not sell them.
Emissions from carbon majors' Australian fossil fuel products
In 2018
Total emissions in Mt CO2-e
Guardian graphic | Source: Australia's Carbon Majors Report 2019
He said their products should be seen through a similar prism to goods that had been banned or had limitations placed on their use on moral grounds, giving the example of Scott Morrison’s announcement that Australia would ban the export of plastic waste, in part because it was ending up in the ocean. Moss said other industries where there were moral constraints included the live sheep trade, asbestos and uranium.
“The only reason we care about these things is the impact they have. That’s a moral argument,” he said. “There is a reason we sell uranium to France and not Pakistan. It’s because if we know something was to go wrong in Pakistan, a safety issue or a dirty bomb, we’re partly culpable.
“In the same way, to say you’re selling coal to a country just to stop someone worse from doing it, that’s just not true. We use supply-side constraints all the time. We should with fossil fuels.”
Coal companies were asked for their response to the emissions analysis.
Peabody said the company recognised climate change was occurring and that human use of fossil fuels contributed to greenhouse gas emissions. “We also recognise coal is essential to affordable, reliable energy and will continue to play a significant role in the global energy mix for the foreseeable future,” a Peabody spokesperson said, adding that technology would be vital in advancing climate change solutions.
Others, including BHP and Glencore, declined to respond. In his speech in July, Mackenzie said the company would limit its direct emissions to 2017 levels by 2022 and set a target of net zero emissions by 2050, but the company faces pressure from shareholders over its membership of lobby groups that promote coal use.
Chevron, listed in the report as the oil and gas company linked to the most pollution, said managing emissions was an integral part of its planning and it had announced goals to reduce emissions intensity (the amount emitted for each dollar earned) from upstream oil and natural gas projects (by 5-10% and 2-5% between 2016 and 2023 respectively).
The UNSW report cites research that global fossil fuel emissions more than doubled between 1988, when the UN’s Intergovernmental Panel on Climate Change was established, and 2016. Emissions were greater from burning fossil fuels in those 28 years than the previous 237.
Moss said big emitters should pay compensation for the harm caused by emissions released since 1990, if not earlier.
He said many of the major producers listed in the report had long histories of pollution and continued to hold vast reserves to be extracted in the future. The researchers give the example of Glencore, which last year reported it had 6,765m tonnes of measured coal resources and 1,565m tonnes of proved marketable reserves. Moss said extracting it all could lead to 15.6bn tonnes of carbon dioxide, about 29 times Australia’s annual emissions.

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Scott Morrison Threatens Crackdown On Protesters Who Would 'Deny Liberty'

The Guardian - 

PM signals action on secondary boycotts of resources companies and says progressives want to tell Australians ‘what you can say, what you can think’
Scott Morrison says Australian mining is under threat and has pointed to ‘worrying development’ of environmental groups targeting businesses in secondary boycotts. Photograph: Dean Lewins/AAP
Scott Morrison has branded environmental protesters “anarchists” and threatened a radical crackdown on the right to protest in a speech claiming progressives are seeking to “deny the liberties of Australians”.
In a speech to the Queensland Resources Council on Friday, the prime minister said a threat to the future of mining was coming from a “new breed of radical activism” and signalled the government would seek to apply penalties to those targeting businesses who provide services to the resources industry.
Civil society groups, including the Human Rights Law Centre and Australian Conservation Foundation, and the Greens immediately attacked the proposal as undemocratic and a bid to stifle a social movement fighting for Australia to take action on climate change.
Morrison told Australian corporations to listen to the “quiet shareholders” and not environmental protesters, who he suggested could shift targets from coal companies to all carbon-intensive industries including power generation, gas projects, abattoirs and airlines.
In a speech proposing limits on free speech advocating boycotts against polluting companies, Morrison said progressives wanted to tell Australians “what you can say, what you can think and tax you more for the privilege of all of those instructions”.
He claimed that “progressivism” – which he labelled a “new-speak type term”, invoking George Orwell – intends “to get in under the radar, but at its heart would deny the liberties of Australians”.
“Apocalyptic in tone, it brooks no compromise,” Morrison said. “It’s all or nothing. Alternative views are not permitted.”
He pointed to the “worrying development” of environmental groups targeting businesses or firms involved in the mining sector with “secondary boycotts”, such as businesses refusing to provide banking, insurance or consultancy services.
“They are targeting businesses of all sizes, including small businesses, like contracting businesses in regional Queensland.”
“Let me assure you this is not something my government intends to allow to go unchecked.
“Together with the attorney general, we are working to identify mechanisms that can successfully outlaw these indulgent and selfish practices that threaten the livelihoods of fellow Australians.”
But Morrison admitted the government “can’t force one Australian company to provide a service to another”.
The Greens were quick to reverse the charge of intolerance and level it at Morrison, with acting leader Adam Bandt labelling him “a direct threat to Australian democracy and freedom of speech”.
“The prime minister’s commitment to outlaw the peaceful, legal protest of Australian individuals and community groups reads like a move straight from the totalitarian’s playbook,” he said.
“Instead of getting tough on the climate crisis, Scott Morrison is dismantling democracy.”
The executive director of the Human Rights Law Centre, Hugh de Kretser, said the plan to crack down on boycotts was “deeply concerning”.
“Protest is an essential part of our democracy,” he said. “To protect our democracy and help ensure a better future for all Australians, governments should be strengthening our rights to come together and protest, not weakening them.”
The Competition and Consumer Act already contains civil penalties for secondary boycotts, which target one business in order to prevent provision of goods or services to another, including if they cause “substantial loss or damage” or substantially lessen competition.
However, secondary boycotts for the “dominant purpose” of environmental protection or consumer protection are permitted.
In 2014 the Abbott government considered applying penalties to environmental boycotts. In 2015 the Harper competition review said in the absence of “compelling evidence” on the point it saw no need for change although the exception should be reassessed “if such evidence arises from future boycott activity”.
Earlier on Friday Morrison told 3AW Radio that there is “of course the right to protest in this country” but claimed recent environmental protests in Melbourne were “well beyond the pale” because protesters had allegedly spat at people in business shirts.
“If it’s not OK to have secondary boycotts being run by unions … it’s not OK for environmental, well, they’re anarchist groups … to be able to disrupt people’s jobs, their livelihoods, to harass people as we saw down in Melbourne,” he said.
The chief executive of the Australian Conservation Foundation, Kelly O’Shanassy, said community campaigning was a “legitimate response” voicing the concerns about global heating shared by millions of Australians.
“People protesting in the streets are not the only ones expressing alarm about climate change – the head of the Defence Force, the deputy governor of the Reserve Bank and the Australian Prudential Regulation Authority have all recently raised serious concerns,” she said.
“To paint this broad community concern as being about fringe-dwelling extremists is an insult to all Australians who want a better future for themselves and their children.
“Politicians have a responsibility to defend our democracy, not degrade it.”

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