What The Paris Conference On Climate Change Can Do For Planet Earth

Los Angeles Times Op-Ed - Bill Mckibben*

Demonstrators make their way down Sixth Avenue in New York during the People's Climate March on Sept. 21, 2014. (Jason DeCrow / Associated Press)

Starting Monday, diplomats and scientists, activists and heads of state at the 2015 U.N. climate change conference in Paris will scramble to reach the first truly global agreement on the greatest problem the planet has ever faced. It will make for compelling headlines, but it's not the real story. Because that already happened.
Think back to Copenhagen in 2009 and the last of the great U.N. climate gatherings. There too the world watched expectantly, only to see negotiations break down. No firm targets, timetables or enforcement mechanisms for cutting carbon emissions were put into place. Copenhagen failed because no real pressure was put on the world's leaders to make a deal. President Obama and Secretary of State Hillary Clinton — and other national leaders — could come home empty-handed and pay almost no political price. It was easier to disappoint a nascent climate movement than it was to stand up to the fossil fuel industry.

The Paris climate conference represents a possible turning point in the fight between the fossil fuel industry and the rest of us.

In the six years since, the power equation has changed, and that's the real story of the Paris conference.
The shift was clear in New York last fall, when 300,000 to 400,000 people marched through the streets demanding action on global warming, the largest demonstration in this country in years. Two days later, Obama told the United Nations: "Our citizens keep marching. We cannot pretend we do not hear them. We have to answer the call."
And a few weeks after that, the United States and China announced a joint pledge to meet specific emissions goals, a first for China and an increased commitment from the U.S. That agreement from the world's largest greenhouse gas emitters has helped push other nations into the fold in Paris.
There have been other victories as well: Obama's rejection of the Keystone XL pipeline, New York state's ban on fracking, Shell's retreat from Arctic drilling. In Australia, plans for the world's largest coal mines have been blocked. Australian Prime Minister Tony Abbott and Canada's Prime Minister Stephen Harper, the Western world's most outspoken advocates for increased carbon extraction, lost their jobs in recent elections. Exxon Mobil, the world's most powerful fossil fuel company, is in the dock for climate deceit that was exposed by the Los Angeles Times, Columbia University's Energy & Environmental Reporting Project and Inside Climate News.
A resurgent environmental movement isn't the only thing that's changed since Copenhagen. Engineers, scientists and technologists have played their part. The price of a solar panel had dropped 80% since 2009. Wind power is now so efficient that countries such as Denmark can supply their power needs from the breeze on many days and send a surplus into the European grid. In the developing world, it's possible to skip the coal age in favor of clean energy. China will use less coal this year than last, and it's building renewable energy infrastructure at a breakneck pace.
If the coal, gas and oil industries no longer enjoy a chokehold on the outcome of climate talks, their power hasn't disappeared. There will be no formal treaty in Paris; everyone knows there aren't enough votes in the Senate to ratify an international treaty based on a rational climate policy. But neither will Paris be a failure: The pledges that governments plan to finalize there should suffice to hold warming to 3 or 3.5 degrees Celsius over the course of the century. Right now, the planet is heading for a 5-degree increase, so that's an improvement.
Still, even 3 degrees means Earth is on a path to destruction. There is wide agreement that any temperature increase greater than 2 degrees Celsius threatens civilization; we passed the 1-degree mark this fall and already the Arctic is melting, the West is confronting epic drought and the ocean is 30% more acidic.
All of this means that Paris should be both a scoreboard and a springboard. It will show how far we've come, and it could launch more progress. Two issues in the negotiations will signal how much more. First, how much aid will go to the poorest nations to help them leapfrog the fossil fuel age and deal with the effects of global warming that are now unavoidable. It will take real money — ongoing, steady support — to substitute alternative energy sources for coal in the developing world. Republicans aren't helping here: 11 days ago , they voted down even $500 million in funding from the United States, one of many explicit efforts to torpedo the negotiations.
The second clue is whether the conference will set a clear goal for not just reducing but ending the use of fossil fuels. Will it establish an efficient way to ratchet up emission pledges, as science and technology evolve? Having wasted the last quarter-century, the world can't afford to keep gearing up for once-a-decade grand gatherings; it needs to move smoothly forward into a 100% renewable energy future.
The Paris climate conference represents a possible turning point in the fight between the fossil fuel industry and the rest of us, but the great murky unknown remains: How much of a margin do physics and chemistry allow a warming Earth? The recent news that October was the hottest month ever recorded on our planet, and that the atmosphere's CO2 level has topped 400 parts per million, sobers any optimism.
Whatever happens in the next two weeks, it almost certainly won't be sufficient. Physics and chemistry don't negotiate. After Paris, we will have to maintain the pressure on our leaders, and hope for a bit of luck.

*Bill McKibben is the founder of the global climate campaign 350.org and a professor of environmental studies at Middlebury College.

Scientists Say Paris Climate Pledges Aren’t Enough To Save The Planet’s Ice

Washington Post - Chris Mooney

The Large Ice Fall of Glacier 1 is seen at the base of the 7,556 m (24,790 ft) Mount Gongga, known in Tibetan as Minya Konka on November 12, 2015 in Hailuogou, Garze Tibetan Autonomous Prefecture, Sichuan province, China. (Photo by Kevin Frayer/Getty Images)

It has been heralded as an unprecedented achievement. This year the vast majority of the world’s nations have issued pledges, or “intended nationally determined contributions” (INDCs), promising a range of emissions cuts as a foundation for an agreement at the Paris climate conference that opens Monday.
But there’s a problem. These commitments, on their own, only have the potential to forge a path that would limit warming to 2.7 degrees Celsius above pre-industrial levels at best, according to the U.N. And other assessments have been even more pessimistic than that, producing higher estimates like 3.5 degrees Celsius by 2100.
That’s well above the 2 degrees C that has been dubbed the final marker of a climatic “safe” zone. And now, a group of scientists who study the “cryosphere” — all the ice and snow in the Earth’s system, at the poles but also in frozen permafrost and mountain glaciers — have unleashed a stark assessment of just how inadequate these currently pledged emissions cuts are (barring a major enhancement of ambitions in Paris). Indeed, they say that if the INDCs are the end of the story, often irreversible changes will usher in that, unfolding over vast time periods, will dramatically raise seas and pour dangerous additional amounts of carbon into the atmosphere.

[The Great Thaw: As temperatures rise, the melting of glaciers is accelerating]

“Reacting with ‘too little, too late’ may lock in the gradual but unavoidable transformation of our Earth, its ecosystems and human communities, in a terrible legacy that may last a thousand years or more,” says the document, issued by the International Cryosphere Climate Initiative (ICCI) and reviewed by a number of leading ice scientists focusing on Greenland, Antarctica, permafrost, Arctic sea ice, and more.
At the core of the report is the fundamental observation that while overall global average temperatures may have only risen about 1 degree Celsius so far, that rise has already been magnified greatly in the Arctic region, the Antarctic peninsula, and also in many high altitude areas where there is a large volume of vulnerable ice.
As a result, the experts say, many of these regions are now close to (or even in some cases past) major thresholds that, once crossed, we can’t reverse without the arrival of a new ice age. In many cases, in just the past few years the situation has become considerably more dire for key elements of the cryosphere — especially for the ice sheet of West Antarctica, where many scientists think a threshold leading to irreversible loss may have already been crossed.

Heimdal Glacier in southern Greenland is seen in a NASA image captured by Langley Research Center’s Falcon 20 aircraft October 13, 2015 and released November 24, 2015. NASA’s Operation IceBridge North is an airborne survey of polar ice aimed at learning how much snow and ice disappeared over the summer, according to a NASA news release. REUTERS/NASA/John Sonntag/Handout via Reuters

So if warming really occurs at the level implied by the INDCs — without dramatic additional steps to cut emissions — the report suggests we can look forward to the following: almost total loss of mountain glaciers around the world; major ice loss from West Antarctica and Greenland; a sea ice-free Arctic in the summer; and a major new source of greenhouse gases wafting out of thawing Arctic permafrost. The latter would be particularly damaging because at a time when human-caused emission levels are still far too high, it would require even steeper cuts to fossil fuel use and deforestation than currently contemplated.
Let’s take some of these problem areas in sequence, starting with the planet’s great ice sheets. West Antarctica may already be destabilized at current levels of warming, but the problems don’t stop there. There’s also Greenland, with its 20 feet worth of potential sea level rise in the form of ice. “The best estimate for the viability threshold of the Greenland ice sheet is around 1.6 degrees above pre-industrial,” said Jonathan Bamber, a glaciologist at the University of Bristol in Britain, on a press call to discuss the ICCI report. “If we go above that, the whole ice sheet becomes a relict of the last interglacial, it is no longer viable.”
The concern is not that this would happen all at once or even in this century, but rather, that it would become locked in to occurring. So the researchers are worried that with the current climate ambitions, we could be committing to many meters of long-term sea level rise. And that’s just the beginning of the consequences of melting a lot of planetary ice.
The report also forecasts that with the levels of warming implied by the INDCs, mountain glaciers around the world — which are often a key source of freshwater to communities — will face a severe threat. “We’re on track at the moment to have most of our mountain glaciers cross the threshold beyond which they’re doomed,” said Graham Cogley, a research with Trent University, on the press call.
And then, well, there’s permafrost — frozen soil spread across vast parts of the northern hemisphere Arctic. In a very troubling finding, the report states that even if global average temperatures are held to just 1.5 degrees Celsius — not a target that’s currently on the table — 30 percent of permafrost today could be thawed at least up through the top several meters of soil. And that would translate, by 2100, into about 50 gigatons of carbon emissions — or more than 180 gigatons of carbon dioxide.

In this Aug. 10, 2009, photo, a hill of permafrost “slumping” from global warming near the remote, boggy fringe of North America, 2,200 kilometers (1,400 miles) from the North Pole, where researchers are learning more about methane seeps in the 25,000 lakes of this vast Mackenzie River Delta, in the Northwest Territories, Canada. (AP Photo/Rick Bowmer)

Such numbers would severely restrict current emissions budgets that are at the center of current policymaking and, indeed, of assessments of the INDCs. “These carbon losses from thawing permafrost currently are not accounted for in our global climate models, and they need to be accounted for if we are going to hit our emissions targets,” said Susan Natali, a permafrost expert with the Woods Hole Research Center, who reviewed the permafrost section of the report.
To top it all off, the report also forecasts a continual decline of Arctic sea ice that, thanks to feedback processes, will further warm the region encompassing Greenland and many key mountain glaciers — and the large store of the world’s permafrost. For the northern hemisphere, in effect, the loss of Arctic sea ice further weakens the cryosphere across the board.
The upshot is that we could be on the verge, in just a matter of decades, of causing changes that will be irreversible at the scale of thousands of years.
“Cryosphere climate change is not like air or water pollution, where the impacts remain local and when addressed, allow ecosystems largely to recover,” the report states. “Cryosphere climate change, driven by the physical laws of water’s response to the freezing point, is different.”

The Guardian View On The Climate Change Summit: There Is No Planet B

The Guardian - Editorial

The world’s hopes for a sustainable future depend on what happens in Paris over the next two weeks

Environmentalist activists in Berlin on the eve of the climate change summit in Paris. Photograph: Stefan Boness/Ipon/SIPA

The current front-runner for best slogan for the Paris climate change summit has to be “there is no planet B”; as for images, it is hard to imagine one more potent than the thousands of pairs of shoes laid in tidy lines in the Place de la République that symbolise the march climate activists had scheduled for Sunday then banned for fear of a repeat of the terrorist attack of a fortnight ago. However equivocal some of the political leadership sometimes appears, the popular movement for greening the economy is in good heart.
This is the 21st UN conference of the parties on climate change, better known as COP, and there are signs of a new maturity that might be the best omen for the future. It is easy to forget that this is an unprecedented attempt at global cooperation, one which has not only moved from event to process, but from protest to movement. For Paris is not only about world leaders trying to find an agreement acceptable to nearly 200 countries for whom the consequences of global warming will be existentially different. It is now also about the place of non-state players, from the indigenous peoples of South America to the world’s most sophisticated cities, and from the individual decisions that each of us makes to the clean energy initiative being launched on Monday by one of the world’s richest men, Bill Gates. One sign of this maturity is the demand from Laurent Fabius, the French foreign affairs minister in charge of this COP, that a deal on a final text should be agreed by next weekend. That would mean the last week of the conference was spent discussing how to put the final communiqué into action.
But there remain highly contentious decisions still to be taken, key wording left in square brackets in the 20-page negotiating text: including the date when carbon emissions peak, the amount of money available to help vulnerable countries adjust to the impact of changing climate, and the assistance available for developing countries that are still heavily reliant on fossil fuels.
The EU has agreed a joint target backed by nationally agreed pledges. Otherwise, engaging countries individually in drawing up their own plans for the speed and scale at which they will cut carbon emissions allows political realities of the kind that have beset both President Obama and successive Australian governments to be accommodated. Critics argue that it risks legitimising foot-dragging, and that is another of the great challenges for the coming fortnight: agreeing a process for monitoring, evaluating and verifying the targets that countries are signing up to – and then putting in a place a system of review that will lead to the targets being ratcheted up until they are tight enough to limit warming to 2 degrees. That is this week’s jackpot, but there will be no individual winner – nor any wide-ranging legally-binding agreement. This is a prize for all, or for none.
The danger of the UN-backed annual negotiations is that they can make tackling climate change look like a problem for other people. It is true that it requires global coordination. But that has to grow from national and local interest. It is here that non-state players, among them religions, have a crucial role in helping us to understand that self-interest demands solidarity.
There is a dangerous tendency that has long been plain in Australia and the US and is becoming explicit now in Britain, to present climate change as a story of loss and sacrifice rather than one of potential gain. The decisions the Conservative government at Westminster has taken since winning the election in May have underscored the idea that cutting carbon emissions is a costly vanity rather than an industrial opportunity. George Osborne reinforced that message in last week’s autumn statement, which it emerged soon afterwards included the withdrawal of all support for carbon capture and storage, essential if fossil fuels like shale gas are to be used safely. (No wonder that according to the weekend Financial Times, businesses like Ikea and Tesco have co-written an angry letter protesting at the damaging confusion in the government’s energy policy.)
Yet to say each of us has a contribution to make is not to underestimate the importance of what happens in the next two weeks. Now is the time to lay the cornerstone for a global strategy to cut and ultimately end carbon emissions. On what happens in a series of temporary structures in the suburbs of one of the world’s oldest and greatest cities depend the hopes for a sustainable future for the planet.

COP-21 Climate Deal In Paris Spells End Of The Fossil Era

London Daily Telegraph -  Ambrose Evans-Pritchard

Much of the fossil industry will go into slow run-off while the new plutocrats will be masters of post-carbon technology

The authorities in Paris have banned any protest marches due to security concerns following the terrorist attacks, so campaigners have left their shoes out instead. Photo: REUTERS/Eric Gaillard

A far-reaching deal on climate change in Paris over coming days promises to unleash a $30 trillion blitz of investment on new technology and renewable energy by 2040, creating vast riches for those in the vanguard and potentially lifting the global economy out of its slow-growth trap.
Economists at Barclays estimate that greenhouse gas pledges made by the US, the EU, China, India, and others for the COP-21 climate summit amount to an epic change in the allocation of capital and resources, with financial winners and losers to match.
They said the fossil fuel industry of coal, gas, and oil could forfeit $34 trillion in revenues over the next quarter century – a quarter of their income – if the Paris accord is followed by a series of tougher reviews every five years to force down the trajectory of CO2 emissions, as proposed by the United Nations and French officials hosting the talks.

By then crude consumption would fall to 72m barrels a day - half OPEC projections - and demand would be in precipitous decline. Most fossil companies would face run-off unless they could reinvent themselves as 21st Century post-carbon leaders, as Shell, Total, and Statoil are already doing.
The agreed UN goal is to cap the rise in global temperatures to 2 degrees centigrade above pre-industrial levels by 2100, deemed the safe limit if we are to pass on a world that is more or less recognisable.
Climate negotiators say there will have to be drastic "decarbonisation" to bring this in sight, with negative net emissions by 2070 or soon after. This means that CO2 will have to be plucked from the air and buried, or absorbed by reforestation.
Such a scenario would imply the near extinction of the coal industry unless there is a big push for carbon capture and storage. It also implies a near total switch to electric cars, rendering the internal combustion engine obsolete.

Effect of current Paris pledges
The Bank of England and the G20's Financial Stability Board aim to bring about a "soft landing" that protects investors and gives the fossil industry time to adapt by forcing it to confront the issue head on.
Barclays said $21.5 trillion of investment in energy efficiency will be needed by 2040 under the current pledges, which cover 155 countries and 94pc of the global economy. It expects a further $8.5 trillion of spending on solar, wind, hydro, energy storage, and nuclear power.
Those best-placed to profit in Europe are: Denmark's wind group Vestas; Schneider and ABB for motors and transmission; Legrand for low voltage equipment; Alstom and Siemens for rail efficiency; Philips, and Osram for LEDs and lighting.

But this is a minimalist scenario. While the Paris commitments suggest a watershed moment, they do not go far enough to meet the targets set by the Intergovernmental Panel on Climate Change (IPPC). The planet has already used up two-thirds of the allowable "carbon budget" of 2,900 gigatonnes (GT), and will have used up three quarters of the remaining 1,000 GT by 2030.
Barclays advised clients to prepare for a more radical outcome, entailing almost $45 trillion of spending on different forms of decarbonisation.
"The fact that COP-21 in itself is clearly not going to put the world on a 2 degree track does not mean that fossil-fuel companies can simply carry on with business-as-usual. We think they should be stress-testing their business models against a significant tightening of global climate policy over the next two decades," it said.
The main enforcement tool would be a rise in carbon prices to an estimated $140 a tonne by 2040 - either in the form of a tax or an emissions trading scheme. The pincer coming from the other side would an assault on direct fossil fuel subsidies, estimated at $550bn a year by the International Energy Agency.

Michael Jacobs from the Global Commission on Energy and Climate said the Paris accord is an instrument of economic signalling. "It is telling markets and investors that there is a massive opportunity before them," he said.
It is not yet certain that there will be a binding agreement. There could still be a dispute over the promised $100bn a year of mitigation funding for developing countries, though this issue is more symbolic than real when set against the trillions at stake. "It's peanuts," said Christiana Figueres, the UN's climate chief.
The mood in Paris is radically different from the Copenhagen summit in 2009, poisoned by a 'North-South' split over who is responsible, and who should pay to clean up the greenhouse legacy.

"What has really changed everything is that the cost of renewables has come down so far: what looked impossible six years ago in Copenhagen is now possible," said Mark Lewis, the chief author of the Barclays report. Renewables made up half of all new power added worldwide last year.
"The average cost of global solar was $400 a megawatt/hour worldwide in 2010. It fell to $130 in 2014, and now it has fallen below $60 in the best locations. Almost nobody could have imagined this six years ago," he said.
Mr Lewis said the next big breakthrough - perhaps within five years - will be in cheap energy storage, conquering the curse of intermittency and accelerating an unstoppable snowball effect driven by market forces. The IEA expects solar and wind capacity to rise eightfold under a 2 degree trajectory.

The historic inflexion point was a deal by US President Barack Obama and China's Xi Jinping last year to push for radical curbs, entirely changing the character of global climate politics. "The two 800-pound gorillas are working together," says Todd Stern, the chief US climate negotiator.
China has in effect switched sides since Copenhagen, no small matter for a country that now emits as much CO2 as the US and the EU combined. It has embraced green energy with the zeal of the converted, rushing to clean up its toxic cities and head off a middle-class revolt that threatens the legitimacy of the Communist regime.
It will introduce a cap-and-trade system for emissions in 2017. The dirtiest coal plants are being shut down. Some 200 GW of solar capacity are to be installed by the end of the decade. President Xi Jinping has vowed to cap total CO2 emissions by 2030 - if not earlier.
Mr Jacobs said a deal in Paris is highly likely. "You can never rule out a break-down. These meetings always go to the wire. But we have gone past the turning point in the US and China, and both countries have come to the realisation that it is possible to decarbonise without hurting economic growth," he said.
It will not be a legally-binding treaty, but it is expected to have the same effect as each country transposes the targets into its own law. In the US it will be enforced through the legal mechanism of the Clean Air Act, anchored on earlier accords, without need for Senate ratification.
The sums of money are colossal. Macro-economists say this is just what is needed to soak up the global savings glut and rescue the world from its 1930s liquidity trap. There might even be a boom.

Report Shows Seven-Fold Growth In Councils Dumping Fossil Fuels

350.org

Local governments representing $5.5 billion have now committed to go fossil free.

A report launched today by 350.org Australia highlights the growth in local governments divesting from fossil fuels.
According to the report, councils that have committed to divest represent $5.5billion in funds under management.
In addition, there has been a seven-fold growth in the number of councils moving their money out of coal, oil, and gas over the past year. From 2 councils divested at the end of 2014, with 14 local governments committed to going fossil free at the time of writing.
“Local governments of all political persuasions are leading the way when it comes to taking ambitious and much needed action on climate change. The size and number of councils divesting is only increasing. It’s high time our Federal Government read the writing on the wall and followed their lead,” said Isaac Astill, a divestment campaigner with 350.org Australia.
Divestment decisions are being made by diverse and significant local governments. Canberra was the world’s first national capital to join the fossil fuel divestment movement.
Home to the world’s largest coal port, Newcastle City Council has also committed to divest, despite strong political and industry pressure not to.
Last month the City of Melbourne, led by Liberal Party Lord Mayor Robert Doyle, joined the ranks of councils going fossil free.
Speaking about his council’s decision to divest last year, Dr Brad Pettitt, Mayor of the City of Fremantle, said: “It’s the responsibility of our banks, superannuation funds, and governments that have custody of our money to use this money to protect, and not damage, our environment.”
The decisions of local governments to divest from the big four banks due to their fossil fuel lendings is already sending a powerful message to the banks that supporting fossil fuels is bad for business.
“Lismore is on the frontline of the fight against the coal seam gas industry. Moving council money away from financial institutions that support the fossil fuel industry is a practical and sensible way for councils to ensure we are doing everything we can to leave this industry behind,” said Lismore Mayor Jenny Dowell of her city’s decision to divest.
Globally, as momentum for local governments to divest grows, the divestment movement is escalating globally. Approximately 490 institutions have committed to divesting, equating to well over $US2.6 trillion of investment money.
In the past 12 months, major institutions such as The Rockefeller Brothers Fund, one of the world’s largest insurance companies Allianz, and the Norwegian Sovereign Wealth Fund have committed to divest.

Links

• The full report – Local Government Leadership on Fossil Fuel Divestment: A report into the growing movement of councils going fossil free – can be accessed here.
• A full list of divestment commitments can be accessed here.

Australians Join Global Rallies For Climate Change Action Ahead Of Paris Talks

ABC News

Thousands of people marched on the lawns of Canbera's Parliament House. (ABC News: Ruby Cornish)

Thousands of Australians have joined a worldwide wave of marches on the eve of United Nations climate change negotiations in Paris, calling for stronger measures to combat global warming.
Events were held today in Sydney, Canberra, Perth and Hobart, as well as regional and rural towns around Australia, joining about 600 other cities in more than 120 countries around the world.
Protests have already taken place in Brisbane, Melbourne and Darwin.
In Sydney, thousands of people gathered in The Domain before marching to the Opera House.

A dog joined the People's Climate rally in Adelaide. ABC News: Malcolm Sutton

Doctors, firefighters and religious leaders were among the crowd, which called for governments to keep temperatures from rising by more than 2 degrees Celsius - the limit scientists say would trigger dangerous climate change.
Currently temperatures have risen 1C since the Industrial Revolution.
Among the placards held by attendees was a sign warning: "There is no Planet B".
In Canberra, a crowd of about 5,000 marched from Parliament House, down the ramp and along Commonwealth Avenue before arriving at the Aboriginal Tent Embassy in front of Old Parliament House.
The crowd chanted "from coal and gas to wind and sun. This power shift has begun" and "we are unstoppable, another world is possible".
At the tent embassy the group was welcomed by Aboriginal elders who invited the group onto the land.
The ACT Conservation Council's Phoebe Howe said the march was about celebrating successes as well as advocating for more action.
"Often at these climate marches it can feel like we're protesting something that's so hard to change, but the reality is that there is so much climate action already happening right across the world and here in Canberra's a great example of that," she said.
"We're excited to celebrate that and to invite everyone participating today to find ways they can stay involved and keep pushing so that together we can find that global solution."

This person, kitted out with a gas mask at Canberra's People's Climate march, shouted slogans such as: "From coal and gas to wind and sun, this power shift has begun." ABC News: Ian Cutmore

In Hobart about 1,000 people gathered on the lawns of Parliament House to listen to a series of speakers. Despite the location of the rally, the organisers did not include politicians in the line-up.
Many people carried placards and signs calling for a focus on renewable energy and less of a reliance on fossil fuels.
The Greens were present and called for more action from Tasmania's state Liberal Government on clarifying its climate change policy.
Wildlife also featured strongly, with participants dressed as parrots and Tasmanian devils to draw attention to the plight of endangered species.
The crowd fell silent for a minute at the start of the rally, in tribute to the victims of the Paris terror attacks.
In Adelaide, a crowd marched from the Torrens Parade ground in the CBD to Victoria Square.
Organisers say around 6,000 people have attended the rally in Adelaide, making it the largest ever in South Australia on the issue.
The march came as the South Australian Government released a plan to make Adelaide the "world's first carbon neutral city".
During the rally, another much-smaller group of about 30 marched the opposite direction calling for a stop to child abuse and more action on the issue from the SA Government.
In Perth, organisers said more than 7,000 people joined in the national rally with around 350 community groups joining Aboriginal elders and religious leaders to march from Wellington Square into the city.
The recent bushfires in Esperance were a hot topic.
WA president of the United Firefighters Union Kevin Jolly said changing fire seasons means the Government needed to invest more resources.
"The summer period ... from December through to march has been extended. You know we are here in November and in Western Australia and we've already had catastrophic fires," he said.
"There are no sceptics of climate change when you are behind a hose. Firefighters are working hard and longer and the Government needs to recognise that and put in more resources." Who's who at the Paris conference?
Some 150 leaders, including Prime Minister Malcolm Turnbull, US president Barack Obama, China's

Important players are at the Paris climate conference.

Xi Jinping, India's Narendra Modi and Russian president Vladimir Putin, will attend the start of the Paris conference, which is tasked with reaching the first truly universal climate pact.
The goal is to limit average global warming to 2C or less over pre-Industrial Revolution levels by curbing fossil fuel emissions blamed for climate change.
If they fail, scientists warn the world may become increasingly inhospitable to human life, with superstorms, drought and rising sea levels that swamp vast areas of land.
On the eve of the protests, French president Francois Hollande warned of the obstacles ahead for the 195 nations that will be represented at the talks following more than two decades of bickering.
"Man is the worst enemy of man. We can see it with terrorism," said Mr Hollande, after leading ceremonies in Paris to mourn the victims of the deadly November 13 bombing and shooting attacks that sowed terror in the French capital.
"But we can say the same when it comes to climate. Human beings are destroying nature, damaging the environment. It is therefore for human beings to face up to their responsibilities for the good of future generations."
UN secretary-general Ban Ki-moon said he was optimistic of success in the talks, due to end on December 11, but emphasised all sides must be prepared to compromise.
"I am urging the world leaders that they must agree on the middle ground, there is no such perfect agreement in this world," he said.