Biden says the US will rejoin the Paris climate agreement in 77 days. Then Australia will really feel the heat


Christian Downie, Australian National University

When the US formally left the Paris climate agreement, Joe Biden tweeted that “in exactly 77 days, a Biden Administration will rejoin it”.

The US announced its intention to withdraw from the agreement back in 2017. But the agreement’s complex rules meant formal notification could only be sent to the United Nations last year, followed by a 12-month notice period — hence the long wait.

While diplomacy via Twitter looks here to stay, global climate politics is about to be upended — and the impacts will be felt at home in Australia if Biden delivers on his plans.

Biden’s position on climate change

Under a Biden administration, the US will have the most progressive position on climate change in the nation’s history. Biden has already laid out a US$2 trillion clean energy and infrastructure plan, a commitment to rejoin the Paris agreement and a goal of net-zero emissions by 2050.

As Biden said back in July when he announced the plan:

If I have the honour of being elected president, we’re not just going to tinker around the edges. We’re going to make historic investments that will seize the opportunity, meet this moment in history.

And his plan is historic. It aims to achieve a power sector that’s free from carbon pollution by 2035 — in a country with the largest reserves of coal on the planet.

Biden also aims to revitalise the US auto industry and become a leader in electric vehicles, and to upgrade four million buildings and two million homes over four years to meet new energy efficiency standards.

Can he do it under a divided Congress?

While the votes are still being counted — as they should (can any Australian believe we actually need to say this?) — it seems likely the Democrats will control the presidency and the House, but not the Senate.

This means Biden will be able to re-join the Paris agreement, which does not require Senate ratification. But any attempt to legislate a carbon price will be blocked in the Senate, as it was when then-President Barack Obama introduced the Waxman-Markey bill in 2010.

In any case, there’s no reason to think a carbon price is a silver bullet, given the window to act on climate change is closing fast.




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What’s needed are ambitious targets and mandates for the power sector, transport sector and manufacturing sector, backed up with billions in government investment.

Fortunately, this is precisely what Biden is promising to do. And he can do it without the Senate by using the executive powers of the US government to implement a raft of new regulatory measures.

Take the transport sector as an example. His plan aims to set “ambitious fuel economy standards” for cars, set a goal that all American-built buses be zero emissions by 2030, and use public money to build half a million electric vehicle charging stations. Most of these actions can be put in place through regulations that don’t require congressional approval.

And with Trump out of the White House, California will be free to achieve its target that all new cars be zero emissions by 2035, which the Trump administration had impeded.

If that sounds far-fetched, given Australia is the only OECD country that still doesn’t have fuel efficiency standards for cars, keep in mind China promised to do the same thing as California last week.

What does this mean for Australia?

For the last four years, the Trump administration has been a boon for successive Australian governments as they have torn up climate policies and failed to implement new ones.

Rather than witnessing our principal ally rebuke us on home soil, as Obama did at the University of Queensland in 2014, Prime Minister Scott Morrison has instead benefited from a cosy relationship with a US president who regularly dismisses decades of climate science, as he does medical science. And people are dying as a result.

Obama on climate change at the University of Queensland.

For Australia, the ambitious climate policies of a Biden administration means in every international negotiation our diplomats turn up to, climate change will not only be top of the agenda, but we will likely face constant criticism.

Indeed, fireside chats in the White House will come with new expectations that Australia significantly increases its ambitions under the Paris agreement. Committing to a net zero emissions target will be just the first.

The real kicker, however, will be Biden’s trade agenda, which supports carbon tariffs on imports that produce considerable carbon pollution. The US is still Australia’s third-largest trading partner after China and Japan — who, by the way, have just announced net zero emissions targets themselves.

Should the US start hitting Australian goods with a carbon fee at the border, you can bet Australian business won’t be happy, and Morrison may begin to re-think his domestic climate calculus.

And what political science tells us is if international pressure doesn’t shift a country’s position on climate change, domestic pressure certainly will.




Read more:
Under Biden, the US would no longer be a climate pariah – and that leaves Scott Morrison exposed


With Biden now in the White House, it’s not just global climate politics that will be turned on its head. Australia’s failure to implement a serious domestic climate and energy policy could have profound costs.

Costs, mind you, that are easily avoidable if Australia acts on climate change, and does so now.The Conversation

Christian Downie, Australian Research Council DECRA Fellow, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

China just stunned the world with its step-up on climate action – and the implications for Australia may be huge



Lukas Coch/AAP

Hao Tan, University of Newcastle; Elizabeth Thurbon, UNSW; John Mathews, Macquarie University, and Sung-Young Kim, Macquarie University

China’s President Xi Jinping surprised the global community recently by committing his country to net-zero emissions by 2060. Prior to this announcement, the prospect of becoming “carbon neutral” barely rated a mention in China’s national policies.

China currently accounts for about 28% of global carbon emissions – double the US contribution and three times the European Union’s. Meeting the pledge will demand a deep transition of not just China’s energy system, but its entire economy.

Importantly, China’s use of coal, oil and gas must be slashed, and its industrial production stripped of emissions. This will affect demand for Australia’s exports in coming decades.

It remains to be seen whether China’s climate promise is genuine, or simply a ploy to win international favour. But it puts pressure on many other nations – not least Australia – to follow.

A man walking against an industrial skyline
It remains to be seen whether China will deliver on its climate pledge.
Da qing/AP

Goodbye, fossil fuels

Coal is currently used to generate about 60% of China’s electricity. Coal must be phased out for China to meet its climate target, unless technologies such as carbon-capture and storage become commercially viable.

Natural gas is increasingly used in China for heating and transport, as an alternative to coal and petrol. To achieve carbon neutrality, China must dramatically reduce its gas use.

Electric vehicles and hydrogen fuel-cell vehicles must also come to dominate road transport – currently they account for less than 2% of the total fleet.




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China must also slash the production of carbon-intensive steel, cement and chemicals, unless they can be powered by renewable electricity or zero-emissions hydrogen. One report suggests meeting the target will mean most of China’s steel is produced using recycled steel, in a process powered by renewable electricity.

Modelling in that report suggests China’s use of iron ore – and the coking coal required to process it into steel – will decrease by 75%. The implications for Australia’s mining industry would be huge; around 80% of our iron ore is exported to China.

It is critically important for Australian industries and policymakers to assess the seriousness of China’s pledge and the likelihood it will be delivered. Investment plans for large mining projects should then be reconsidered accordingly.

Conversely, China’s path towards a carbon neutral economy may open up new export opportunities for Australia, such as “green” hydrogen.

A bust road in China
To meet its pledge, China must decarbonise its transport system.
DIEGO AZUBEL/EPA

A renewables revolution

Solar and wind currently account for 10% of China’s total power generation. For China to meet the net-zero goal, renewable energy generation would have to ramp up dramatically. This is needed for two reasons: to replace the lost coal-fired power capacity, and to provide the larger electricity needs of transport and heavy industry.

Two factors are likely to reduce energy demand in China in coming years. First, energy efficiency in the building, transport and manufacturing sectors is likely to improve. Second, the economy is moving away from energy- and pollution-intensive production, towards an economy based on services and digital technologies.

It’s in China’s interests to take greater action on climate change. Developing renewable energy helps China build new “green” export industries, secure its energy supplies and improve air and water quality.

A solar array in China
A transition to renewable energy would improve air pollution in China.
Sam McNeil/AP

The global picture

It’s worth considering what factors may have motivated China’s announcement, beyond the desire to do good for the climate.

In recent years, China has been viewed with increasing hostility on the world stage, especially by Western nations. Some commentators have suggested China’s climate pledge is a bid to improve its global image.

The pledge also gives China the high ground over a major antagonist, the US, which under President Donald Trump has walked away from its international obligations on climate action. China’s pledge follows similar ones by the European Union, New Zealand, California and others. It sets an example for other developing nations to follow, and puts pressure on Australia to do the same.




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The European Union has also been urging China to take stronger climate action. The fact Xi made the net-zero pledge at a United Nations meeting suggests it was largely targeted at an international, rather than Chinese, audience.

However, the international community will judge China’s pledge on how quickly it can implement specific, measurable short- and mid-term targets for net-zero emissions, and whether it has the policies in place to ensure the goal is delivered by 2060.

Much is resting on China’s next Five Year Plan – a policy blueprint created every five years to steer the economy towards various priorities. The latest plan, covering 2021–25, is being developed. It will be examined closely for measures such as phasing out coal and more ambitious targets for renewables.

Also key is whether the recent rebound of China’s carbon emissions – following a fall from 2013 to 2016 – can be reversed.

President Xi and President Trump
President Xi, left, has taken the high ground over the Trump-led US with its bold climate plan.
AP

Wriggle room

The 2060 commitment is bold, but China may look to leave itself wriggle room in several ways.

First, Xi declared in his speech that China will “aim to” achieve carbon neutrality, leaving open the option his nation may not meet the target.

Second, the Paris Agreement states that developed nations should provide financial resources and technological support to help developing countries reduce their emissions. China may make its delivery of the pledge conditional on this support.

Third, China may seek to game the way carbon neutrality is measured – for example, by insisting it excludes carbon emissions “embodied” in imports and exports. This move is quite likely, given exports account for a significant share of China’s total greenhouse gas emissions.

So for the time being, the world is holding its applause for China’s commitment to carbon neutrality. Like every nation, China will be judged not on its climate promises, but on its delivery.




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The Conversation


Hao Tan, Associate professor, University of Newcastle; Elizabeth Thurbon, Scientia Fellow and Associate Professor in International Relations / International Political Economy, UNSW; John Mathews, Professor Emeritus, Macquarie Business School, Macquarie University, and Sung-Young Kim, Senior Lecturer in International Relations, Discipline of Politics & International Relations, Macquarie School of Social Sciences, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: Sunspots do affect our weather, a bit, but not as much as other things



NASA

Robert McLachlan, Massey University


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz


Are we headed for a period with lower Solar activity, i.e. sunspots? How long will it last? What happens to our world when global warming and the end of this period converge?

When climate change comes up in conversation, the question of a possible link with the Sun is often raised.

The Sun is a highly active and complicated body. Its behaviour does change over time and this can affect our climate. But these impacts are much smaller than those caused by our burning of fossil fuels and, crucially, they do not build up over time.

The main change in the Sun is an 11-year Solar cycle of high and low activity, which initially revealed itself in a count of sunspots.

One decade of solar activity in one hour.

Sunspots have been observed continuously since 1609, although their cyclical variation was not noticed until much later. At the peak of the cycle, about 0.1% more Solar energy reaches the Earth, which can increase global average temperatures by 0.05-0.1℃.

This is small, but it can be detected in the climate record.

It’s smaller than other known sources of temperature variation, such as volcanoes (for example, the large eruption of Mt Pinatubo, in the Philippines in 1991, cooled Earth by up to 0.4℃ for several years) and the El Niño Southern Oscillation, which causes variations of up to 0.4℃.




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And it’s small compared to human-induced global warming, which has been accumulating at 0.2℃ per decade since 1980.

Although each 11-year Solar cycle is different, and the processes underlying them are not fully understood, overall the cycle has been stable for hundreds of millions of years.

A little ice age

A famous period of low Solar activity, known as the Maunder Minimum, ran from 1645 to 1715. It happened at a similar time as the Little Ice Age in Europe.

But the fall in Solar activity was too small to account for the temperature drop, which has since been attributed to volcanic eruptions.

Solar activity picked up during the 20th century, reaching a peak in the cycle that ran from 1954 to 1964, before falling away to a very weak cycle in 2009-19.

Bear in mind, though, that the climatic difference between a strong and a weak cycle is small.

Forecasting the Solar cycle

Because changes in Solar activity are important to spacecraft and to radio communications, there is a Solar Cycle Prediction Panel who meet to pool the available evidence.

Experts there are currently predicting the next cycle, which will run to 2030, will be similar to the last one. Beyond that, they’re not saying.

If activity picks up again, and its peak happened to coincide with a strong El Niño, we could see a boost in temperatures of 0.3℃ for a year or two. That would be similar to what happened during the El Niño of 2016, which featured record air and sea temperatures, wildfires, rainfall events and bleaching of the Great Barrier Reef.

The extreme weather events of that year provided a glimpse into the future. They gave examples of what even average years will look like after another decade of steadily worsening global warming.

A journey to the Sun

Solar physics is an active area of research. Apart from its importance to us, the Sun is a playground for the high-energy physics of plasmas governed by powerful magnetic, nuclear and fluid-dynamical forces.

The Solar cycle is driven by a dynamo coupling kinetic, magnetic and electrical energy.




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That’s pretty hard to study in the lab, so research proceeds by a combination of observation, mathematical analysis and computer simulation.

Two spacecraft are currently directly observing the Sun: NASA’s Parker Solar Probe (which will eventually approach to just 5% of the Earth-Sun distance), and ESA’s Solar Orbiter, which is en route to observe the Sun’s poles.

Hopefully one day we will have a better picture of the processes involved in sunspots and the Solar cycle.The Conversation

Exploring the 11-year Solar cycle.

Robert McLachlan, Professor in Applied Mathematics, Massey University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Marine life found in ancient Antarctica ice helps solve a carbon dioxide puzzle from the ice age



Chris Fogwill, Author provided

Chris Turney, UNSW and Chris Fogwill, Keele University

Evidence of minute amounts of marine life in an ancient Antarctic ice sheet helps explain a longstanding puzzle of why rising carbon dioxide (CO₂) levels stalled for hundreds of years as Earth warmed from the last ice age.

Our study
shows there was an explosion in productivity of marine life at the surface of the Southern Ocean thousands of years ago.




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And surprisingly, this marine life once played a part regulating the climate. Hence, this finding has big implications for future climate change projections.

Walking into the past

Our research took us on a four-hour flight from Chile to the Weddell Sea, at the extreme southern end of the Atlantic Ocean, to land on an ice runway at a frigid latitude of 79° south.

Our Ilyshion aircraft landed on the Union Glacier (Antarctic Logistics and Expeditions).
Chris Turney, Author provided

The Weddell Sea is frequently choked with sea ice and has been hazardous to ships since the earliest explorers ventured south.

In 1914, the Anglo-Irish explorer Ernest Shackleton and his men became stuck here for two years, 1,000 kilometres from civilisation. They faced isolation, starvation, freezing temperatures, gangrene, wandering icebergs and the threat of cannibalism.

Surviving here is tough, as is undertaking science.




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What an ocean hidden under Antarctic ice reveals about our planet’s future climate


We spent three weeks in the nearby Patriot Hills, drilling through ice to collect samples.

Normally when scientists collect ice samples, they drill a deep core vertically down through the annual layers of snow and ice. We did something quite different: we went horizontal by drilling a series of shorter cores across the icescape.

That’s because the Patriot Hills is a fiercely wild place strafed by Weddell Sea cyclones that dump large snowfalls, followed by strong frigid winds (called katabatic winds) pouring off the polar plateau.

Those katabatic winds blowing hard.

As the winds blow throughout the year, they remove the surface ice in a process called sublimation. Older, deeper ice is drawn up to the surface. This means walking across the blue ice towards Patriot Hills is effectively like travelling back through time.

A walk across the blue ice is a walk back in time.
Matthew Harris, Keele University, Author provided

The exposed ice reveals what was happening during the transition from the last ice age around 20,000 years ago into our present warmer world, known as the Holocene.

The Antarctic Cold Reversal

As Earth was warming, carbon dioxide levels in the atmosphere were rising rapidly from around 190 to 280 parts per million.

But the warming trend wasn’t all one way.

Starting around 14,600 years ago, there was a 2,000 year-long period of cooling in the Southern Hemisphere. This period is called the Antarctic Cold Reversal, and is where CO₂ levels stalled at around 240 parts per million.

Why that happened was the puzzle, but understanding it could be crucial for improving today’s climate change projections.

Finding life in the ice

Over three weeks we battled the winds and snow to make a detailed collection of ice samples spanning the end of the last ice age.

We collected sample of ice to study later in the lab.
Chris Turney, Author provided

To our surprise, hidden in our ice samples were organic molecules – remnants of marine life thousands of years ago. They came from the cyclones off the Weddell Sea, which swept up organic molecules from the ocean surface and dumped them onshore to be preserved in the ice.

Antarctic ice, which forms from snowfall, usually only tells scientists about the climate. What’s exciting about finding evidence of lifẻ in ancient Antarctic ice is that, for the first time, we can reconstruct what was happening offshore in the Southern Ocean at the same time, thousands of years ago.

We found an unusual period, displaying high concentrations and a diverse range of marine microplankton. This increased ocean productivity coincided with the Antarctic Cold Reversal.

Melting sea ice in summer sustains marine life

Our climate modelling reveals the Antarctic Cold Reversal was a time of massive change in the amount of sea ice across the Southern Ocean.

Sea ice formed in winter melts in summer, and dumps nutrients into the ocean.
Shutterstock

As the world lurched out of the last ice age, the summer warmth destroyed large amounts of sea ice that had formed through winter. When the sea ice melts, it releases valuable nutrients into the Southern Ocean, and fuelled the explosion in marine productivity we found in the ice on the continent.

This marine life caused more carbon dioxide to be drawn from the atmosphere as it photosynthesised, similar to the way plants use carbon dioxide. When the marine life die they sink to the floor, locking away the carbon. The amount of carbon dioxide absorbed in the ocean was sufficiently large to register around the world.

What this mean for climate change today

Today, the Southern Ocean absorbs some 40% of all carbon put in the atmosphere by human activity, so we urgently need a better understand the drivers of this important part of the carbon cycle.




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The last ice age tells us why we need to care about a 2℃ change in temperature


Marine life in the Southern Ocean still plays an important role in regulating the amount of atmospheric carbon dioxide.

But as the world warms with climate change, less sea ice will be formed in polar regions. This natural carbon sink of marine life will only weaken, increasing global temperatures further.

It’s a timely reminder that while the Antarctic may seem remote, it’s impact on our future climate is closer and more connected than we might think.The Conversation

Chris Turney, Professor of Earth Science and Climate Change, Director of the Changing Earth Research Centre and the Chronos 14Carbon-Cycle Facility at UNSW, and Node Director of the ARC Centre of Excellence for Australian Biodiversity and Heritage, UNSW and Chris Fogwill, Professor of Glaciology and Palaeoclimatology, Head of School Geography, Geology and the Environment and Director of the Institute for Sustainable Futures, Keele University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We dug up Australian weather records back to 1838 and found snow is falling less often



State Library of South Australia

Joelle Gergis, Australian National University and Linden Ashcroft, University of Melbourne

As we slowly emerge from lockdown, local adventures are high on people’s wish lists. You may be planning a trip to the ski fields, or even the nearby hills to revel in the white stuff that occasionally falls around our southern cities after an icy winter blast.

Our new research explores these low-elevation snowfall events. We pieced together weather records back to 1838 to create Australia’s longest analysis of daily temperature extremes and their impacts on society.

These historical records can tell us a lot about Australia’s pre-industrial climate, before the large-scale burning of fossil fuels tainted global temperature records.

They also help provide a longer context to evaluate more recent temperature extremes.

We found snow was once a regular feature of the southern Australian climate. But as Australia continues to warm under climate change, cold extremes are becoming less frequent and heatwaves more common.

Heatwaves in Adelaide are becoming more common.
David Mariuz/AAP

Extending Australia’s climate record

Data used by the Bureau of Meteorology to study long-term weather and climate dates back to the early 1900s. This is when good coverage of weather stations across the country began, and observations were taken in a standard way.

But many older weather records exist in national and state archives and libraries, as well as local historical societies around the country.




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We analysed daily weather records from the coastal city of Adelaide and surrounding areas, including the Adelaide Hills, back to 1838. Adelaide is the Australian city worst affected by heatwaves, and the capital of our nation’s driest state, South Australia.

To crosscheck the heatwaves and cold extremes identified in our historical temperature observations, we also looked at newspaper accounts, model simulations of past weather patterns, and palaeoclimate records.

The agreement was remarkable. It demonstrates the value of historical records for improving our estimation of future climate change risk.

Weather journal of Adelaide’s historical climate held by the National Archives of Australia.
National Archives of Australia

‘Limpness to all mankind’

While most other historical climate studies have looked at annual or monthly values, the new record enabled us to look at daily extremes.

This is important, because global temperature increases are most clearly detected in changes to extreme events such as heatwaves. Although these events may only last a few days, they have very real impacts on human health, agriculture and infrastructure.

Our analysis focused on the previously undescribed period before 1910, to extend the Bureau of Meteorology’s official record as far as possible.

Using temperature observations, we identified 34 historical heatwaves and 81 cold events in Adelaide from 1838–1910. We found more than twice as many of these “snow days” by conducting an independent analysis of snowfall accounts in historical documents.

Almost all the events in the temperature observations were supported by newspaper reports. This demonstrated our method can accurately identify historical temperature extremes.

For example, an outbreak of cold air on June 22, 1908, delivered widespread snow across the hills surrounding Adelaide. The Express and Telegraph newspaper reported:

Many people made a special journey from Adelaide by train, carriage, or motor to revel in the unwonted delight of gazing on such a wide expanse of real snow, and all who did so felt that their trouble was amply rewarded by the panorama of loveliness spread out before their enraptured eyes.

Snowballing at Mount Lofty 29 August 1905.
Source: State Library of South Australia

From December 26-30, 1897, Adelaide was gripped by a heatwave that produced five days above 40℃. Newspapers reported heat-related deaths, agricultural damage, animals dying in the zoo, bushfires and even “burning hot pavements scorching the soles of people’s shoes”. As The Advertiser reported:

When the mercury reaches its “century” (100℉ or 37.6℃) there must be a really uncomfortable experience for everyone. One such day can be struggled with; but six of them in a fortnight, three in succession — that is a thing to bring limpness to all mankind.

On December 31, 1897, the South Australian Register wrote prophetically of future Australian summers:

May Heaven preserve us from being here when the “scorchers” try and add a few degrees to the total.

Newspaper account of a deadly heatwave published in the South Australian Register on Friday 31 December 1897.
National Library of Australia

A longer view

While Australia has a long history of hot and cold extremes, our extended analysis shows that their frequency and intensity is changing.

The quality of the very early part of the record is still uncertain, so the information from the 1830s and 1840s must be treated with caution. That said, there is excellent agreement with newspaper and other historical records.

Our research suggests low-elevation snow events around Adelaide have become less common over the past 180 years. This can be seen in both temperature observations and independent newspaper accounts. For example, snowfall was exceptionally high in the 1900s and 1910s — more than four times more frequent than other decades.




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We also found heatwaves are becoming more frequent in Adelaide. The decade 2010–19 has the highest count of heatwaves of any decade in the record. Although recent heatwaves are not significantly longer than those of the past, our analysis showed heatwaves of up to ten days are possible.

Previous Australian studies have identified an increase in extreme heat and a corresponding decrease in cold events. However, this is the longest analysis in Australia, and the first to systematically combine instrumental and documentary information.

Number of heatwaves identified in Adelaide from January 1838 to August 2019. No digitised temperature observations are available from 1 January 1848 – 1 November 1856, so these decades are shown in lighter shades.
Author supplied
Number of extreme cold days identified in Adelaide from January 1838 to August 2019. No digitised temperature observations are currently available from 1 January 1848 – 1 November 1856, so these decades are shaded grey.
Author supplied

Learning from the past

This study shows we can use historical weather records to get a better picture of Australia’s long-term weather and climate history. By using different sources of information, we can piece together the significant events in our climate history with greater certainty.

Historical records tell us about more than just exciting day trips of the past. They also hold the key to understanding impacts of extreme events, such as heat-related deaths or agricultural damage, in the future.

A better understanding of these pre-industrial extremes will help emergency management services better adapt to increased climate risk, as Australia continues to warm.




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The Conversation


Joelle Gergis, Senior Lecturer in Climate Science, Australian National University and Linden Ashcroft, Lecturer in climate science and science communication, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why drought-busting rain depends on the tropical oceans


Andrew King, University of Melbourne; Andy Pitman, UNSW; Anna Ukkola, Australian National University; Ben Henley, University of Melbourne, and Josephine Brown, University of Melbourne

Recent helpful rains dampened fire grounds and gave many farmers a reason to cheer. But much of southeast Australia remains in severe drought.

Australia is no stranger to drought, but the current one stands out when looking at rainfall records over the past 120 years. This drought has been marked by three consecutive extremely dry winters in the Murray-Darling basin, which rank in the driest 10% of winters since 1900.

Despite recent rainfall the southeast of Australia remains in the grip of a multi-year drought.
Bureau of Meteorology

So what’s going on?

There has been much discussion on whether human-caused climate change is to blame. Our new study explores Australian droughts through a different lens.




Read more:
Rain has eased the dry, but more is needed to break the drought


Rather than focusing on what’s causing the dry conditions, we investigated why it’s been such a long time since we had widespread drought-breaking rain. And it’s got a lot to do with how the temperature varies in the Pacific and Indian Ocean.

Our findings suggest that while climate change does contribute to drought, blame can predominately be pointed at the absence of the Pacific Ocean’s La Niña and the negative Indian Ocean Dipole – climate drivers responsible for bringing wetter weather.

Understanding the Indian Ocean Dipole.

What’s the Indian Ocean Dipole?

As you may already know, the Pacific Ocean influences eastern Australia’s climate through El Niño conditions (associated with drier weather) and La Niña conditions (associated with wetter weather).

The lesser known cousin of El Niño and La Niña across the Indian Ocean is called the Indian Ocean Dipole. This refers to the difference in ocean temperature between the eastern and western sides of the Indian Ocean. It modulates winter and springtime rainfall in southeastern Australia.




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When the Indian Ocean Dipole is “negative”, there are warmer ocean temperatures in the east Indian Ocean, and we see more rain over much of Australia. The opposite is true for “positive” Indian Ocean Dipole events, which bring less rain.

The Murray-Darling Basin experiences high rainfall variability, with decade-long droughts common since observations began. The graph shows seasonal rainfall anomalies from a 1961-1990 average with major droughts marked.
Author provided

What does it mean for the drought?

When the drought started to take hold in 2017 and 2018, we didn’t experience an El Niño or strongly positive Indian Ocean Dipole event. These are two dry-weather conditions we might expect to see at the start of a drought.

Rather, conditions in the Pacific and Indian Oceans were near neutral, with little to suggest a drought would develop.

So why are we in severe, prolonged drought?

The problem is we haven’t had either a La Niña or a negative Indian Ocean Dipole event since winter 2016. Our study shows the lack of these events helps explain why eastern Australia is in drought.

For the southeast of Australia in particular, La Niña or negative Indian Ocean Dipole events provide the atmosphere with suitable conditions for persistent and widespread rainfall to occur. So while neither La Niña or a negative Indian Ocean Dipole guarantee heavy rainfall, they do increase the chances.

What about climate change?

While climate drivers are predominately causing this drought, climate change also contributes, though more work is needed to understand what role it specifically plays.

Drought is more complicated and multidimensional than simply “not much rain for a long time”. It can be measured with a raft of metrics beyond rainfall patterns, including metrics that look at humidity levels and evaporation rates.

What we do know is that climate change can exacerbate some of these metrics, which, in turn, can affect drought.




Read more:
Is Australia’s current drought caused by climate change? It’s complicated


Climate change might also influence climate drivers, though right now it’s hard to tell how. A 2015 study suggests that under climate change, La Niña events will become more extreme. Another study from earlier this month suggests climate change is driving more positive Indian Ocean Dipole events, bringing even more drought.

Unfortunately, regional-scale projections from climate models aren’t perfect and we can’t be sure how the ocean patterns that increase the chances of drought-breaking rains will change under global warming. What is clear is there’s a risk they will change, and strongly affect our rainfall.

Putting the drought in context

Long periods when a La Niña or a negative Indian Ocean Dipole event were absent characterised Australia’s past droughts. This includes two periods of more than three years that brought us the Second World War drought and the Millennium drought.

The longer the time without a La Niña or negative Indian Ocean Dipole event, the more likely the Murray-Darling Basin is in drought.

In the above graph, the longer each line continues before stopping, the longer the time since a La Niña or negative Indian Ocean Dipole event occurred. The lower the lines travel, the less rainfall was received in the Murray Darling basin during this period. This lets us compare the current drought to previous droughts.

During the current drought (black line) we see how the rainfall deficit continues for several years, almost identically to how the Millennium drought played out.

But then the deficit increases strongly in late 2019, when we had a strongly positive Indian Ocean Dipole.

So when will this drought break?

This is a hard question to answer. While recent rains have been helpful, we’ve developed a long-term rainfall deficit in the Murray-Darling Basin and elsewhere that will be hard to recover from without either a La Niña or negative Indian Ocean Dipole event.




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The most recent seasonal forecasts don’t predict either a negative Indian Ocean Dipole or La Niña event forming in the next three months. However, accurate forecasts are difficult at this time of year as we approach the “autumn predictability barrier”.

This means, for the coming months, the drought probably won’t break. After that, it’s anyone’s guess. We can only hope conditions improve.The Conversation

Andrew King, ARC DECRA fellow, University of Melbourne; Andy Pitman, Director of the ARC Centre of Excellence for Climate System Science, UNSW; Anna Ukkola, Research Fellow, Australian National University; Ben Henley, Research Fellow in Climate and Water Resources, University of Melbourne, and Josephine Brown, Lecturer, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Might the bushfire crisis be the turning point on climate politics Australian needs?



The bushfire crisis is big enough to change the government’s emissions policy, but it swill need more.
Shutterstock

John Daley, Grattan Institute and Emily Millane, Grattan Institute

Countries have long periods in which policies change little, and only by increments.

Occasionally there are turning points, when previously intractable policy problems are suddenly resolved, recasting policy for the long term.

Many are asking whether this summer’s environmental catastrophe might be such a turning point – a Port Arthur moment or Australia’s Sandy Hook, Chernobyl or Pearl Harbour.

The short answer is: it is too soon to tell, but the early signals from the federal government are not good.

Crises can provide a window for big policy changes. In such times, the normal political constraints are relaxed, although not for long.

Crisis can beget change

The need for revenue during World War I opened the way for the federal government to levy a national income tax. The terrorist attacks of September 11, 2001 stimulated many changes concerned with national security.

Typically, a crisis only leads to substantial policy changes if there is also a broader understanding about the need to act, and the shape of the change needed.

The economic theories of John Maynard Keynes provided the basis for policies that ensured full employment during and after World War II.

The monetarist theories of Milton Friedman provided the means to limit inflation in the 1970s and 1980s.

A library of pre-existing publications on national security directed policy in the wake of 9/11.

Theory is needed as well

Crisis and economic theory were essential to some of the big reforms under the Hawke and Keating governments, including a new approach to Australian retirement incomes.

Superannuation had been a patchwork of individual employer arrangements since before federation.

The stagflation crisis of simultaneous unemployment and inflation in the 1970s created the conditions for a new approach. Inflation rose to 15%, unemployment to 6%. It led to government-union Accords and deferred wage increases that were the basis for Australia’s universal employee superannuation scheme.




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Australian politics explainer: the Prices and Incomes Accord


Many see the 1986 Chernobyl disaster as a turning point in ending the cold war and dismantling the Soviet Union. Mikhail Gorbachev acted decisively in the midst of a disaster that created a groundswell of support for change bringing in an system (capitalism) which had deep theoretical underpinnings.

Not every crisis leads to change

US President Obama hugs Mark Barden, whose seven year old son Daniel was shot and killed in the Sandy Hook Elementary School attack in 2012.
MICHAEL REYNOLDS/EPA

For decades, gun control has been contentious in the United States, where gun-related homicides are ten times the rates elsewhere. 26 people, including 20 children aged 6 and 7, in a gun massacre at Sandy Hook Elementary School in 2012.

President Obama was personally committed to, and moved fast after the crisis to call for, tighter gun control. But change was stymied by powerful stakeholders.

By contrast, John Howard was successful in moving quickly after the 1996 Port Arthur massacre to tighten gun controls.

The Australian gun lobby lacked the political sophistication of America’s National Rifle Association, and Australia’s political system has fewer veto points than in the US.

The attack on Pearl Harbour in 1941 brought World War II to America, mobilising huge levels of public support for American involvement. Within days, Roosevelt declared war on Japan.

The nation might not be ready

There are high levels of public support for action climate change in Australia, but can we say it is the same as “war fever”?

Australia’s emissions policy has been stuck for a long time. Australia was recently ranked as having the worst climate policy in the world, and some of the worst outcomes.

Australia’s annual emissions are not expected to change much between 2020 and 2030 – which doesn’t give Australia much chance of getting to near zero emissions by 2050, which is generally regarded as what’s needed to avoid runaway climate change.

Many in public policy have spent years developing credible policy responses to climate change. But Australia has repealed or failed to implement five versions of climate policy since 2007.




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There are reasons to believe the summer bushfire crisis won’t be any different.

No-one has accused the Prime Minister of moving too fast or too far in responding to the fires. In his interview with ABC at the weekend, he did not commit to tightening, or even reviewing, Australia’s carbon emissions targets in light of the fires.

Powerful stakeholders continue to deny the need for significant policy change: last month the federal resources minister, Matt Canavan, referred to the “bogeyman of climate change” as a distraction from “shortcomings in managing our land.”

Fake news on social media and in some sections of the mainstream media about an arson emergency has blunted the chance of a broad-based popular groundswell.

There’s hope, but not much

The proposed royal commission might be a means to find a way forward on climate change. But by the time it reports, the fires will be out, and the moment of crisis will have passed.

For now, the fires smoulder on. It’s not too late for the federal government to seize the opportunity for substantial change. State governments may well use the aftermath of the fires to coordinate their responses to climate change – possibly without the Commonwealth. For the moment, they are understandably preoccupied with responding to an ongoing emergency.




Read more:
Bushfires won’t change climate policy overnight. But Morrison can shift the Coalition without losing face


There is a real possibility that Australia will have to wait for another crisis – with different leadership, and more public consensus – before there is significant change on emissions policy.

The bushfire smoke that chokes 10 million people in Sydney, Melbourne, Canberra, and elsewhere will no doubt contribute to changing attitudes, and it might even shift the media’s coverage of climate change, but there’s no guarantee that it will be the policy turning point we need.The Conversation

John Daley, Chief Executive Officer, Grattan Institute and Emily Millane, Senior Associate, Grattan Institute

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bushfires won’t change climate policy overnight. But Morrison can shift the Coalition without losing face



When polling resumes after the summer, Scott Morrison may be surprised by the public’s assessment of his government’s handling of the bushfires.
Mick Tsikas/AAP

Chris Wallace, Australian National University

The hope of many people enduring this summer’s firestorms is that better climate policy will arise phoenix-like from the ashes.

It is expressed loudly, fervently, sometimes abusively by people directly affected and those feeling solidarity with them.

It is also expressed secretly, whispered to like-minded confidants, by others who are part of or allied with the Liberal-National (LNP) coalition government of Prime Minister Scott Morrison.

On Sunday, Morrison indicated that he would take a proposal to establish a royal commission into the bushfires to his Cabinet.

But when it comes to climate policy, there are three possible scenarios in the aftermath of the crisis: everything magically changes for the better, everything stays the same or something different happens.

What these three scenarios look like

Everything magically changes for the better would look like this: Morrison announces the crisis has transformed his previous token admission of a link between bushfires and climate change into a revelation of the reality of global warming, with consequential policy change.

As logical and desirable as this seems, it is unlikely, not least because of Morrison’s character and personal beliefs.

Everything stays the same has a powerful impetus behind it. Morrison does not want policy change any more than his likely successor in the event of leadership change, Peter Dutton.




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Government-friendly journalists and commentators at News Corp and 2GB show no sign of changing tack either, so even if the government wanted to shift its policy, the media environment makes it difficult to do so. The forces of inertia are powerful.

Then there is the slim hope that something different happens. This scenario relies on all three of Australia’s main political groupings – the LNP, Labor and the Greens – realising they each face their own distinct climate policy challenge and rising to it.

As Australian burns, its politicians squabble over who’s to blame and how to prevent future disasters.
David Mariuz/AAP

Avoiding the appearance of a backflip

Opinion polls are not done over the summer holiday period, meaning the LNP has yet to see the impact of the bushfires on their public standing.

When polling resumes, Liberal and National MPs will understand the impact, and they won’t like it. Morrison and others will likely urge party members to hold their course since the next election is years away and a dozen other issues could distract attention from climate policy between now and then.

This tactic can prevail for some time but is not strategically sustainable: firestorms like those in the summer of 2020 will not be the last.




Read more:
Grattan on Friday: When the firies call him out on climate change, Scott Morrison should listen


The emerging LNP argument that inadequate hazard reduction burns are to blame for the current crisis is risible. The Australian who has emerged with the most credibility from the bushfires – NSW Rural Fire Service Commissioner Shane Fitzsimmons – rejects it out of hand.

The LNP’s challenge, then, is to realise its current position won’t hold strategically and to transition to better policy ahead of that becoming obvious, managing the optics to avoid the appearance of a backflip.

The challenge for Labor and the Greens

Labor is benefiting from leader Anthony Albanese’s call for “an adult conversation” in Australia about climate policy. He is astutely citing British Tories like the late Margaret Thatcher and current Prime Minister Boris Johnson, who long ago accepted and acted upon the climate science the Morrison government viscerally rejects.

Labor’s homework now is to reconcile the views and interests of members and supporters prioritising climate policy over mining jobs, and vice versa.

This can and must be done if Labor is to build a coalition of support big enough to win office and then enact the climate and other policies the current firestorms make so urgent.




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The Greens, meanwhile, need to have an internal conversation about whether they want to continue making perfect policy the enemy of the good – leaving Australia with no emissions trading system (ETS) at all, for example, because they would not vote for one that did not meet their every demand – or join in efforts to begin on the path to better policy.

Central to that conversation must be a realisation their current strategy isn’t working – the LNP keeps returning to power.

Greens leader Richard Di Natale has said the bushfires should be a
David Crosling/AAP

A possible way forward

There is an obvious point the LNP, Labor and Greens might momentarily agree upon to move policy forward. It is the ETS proposed by Liberal Prime Minister John Howard in 2007.

Howard saw climate change coming. In late 2006, he established a prime ministerial task group on emissions trading chaired by the secretary of his Department of Prime Minister and Cabinet, Peter Shergold.

The Shergold Report, released in May 2007, said “emissions trading should be preferred to a carbon tax” and among the various kinds possible, a national “cap and trade” ETS was best.

In an address to the Liberal Party Federal Council in October 2007, Howard promised to establish a national ETS starting no later than 2012.

This will be a world-class emissions trading system more comprehensive, more rigorously grounded in economics and with better governance than anything in Europe.

Implementing an emissions trading scheme and setting a long-term goal for reducing emissions will be the most momentous economic decisions Australia will take in the next decade.

This emissions trading system must be built to last. It needs to last not five or 10 years, it needs to last the whole of the 21st century if Australia is to meet our global responsibilities and further build our economic prosperity.

Howard positioned the LNP as the party Australians could trust to implement an ETS in a way that gives “firms and families” the ability to “plan for the future with confidence”.

His authorship – and his framing of his ETS as an act of economic responsibility –provides a fig leaf Morrison can now use to move the LNP to a credible, sustainable and politically viable climate policy position.

“Something different” has to start somewhere. If Morrison can deploy the cunning he showed winning the 2019 election by drawing on Howard’s deep well of credibility within the LNP to implement the plan himself and then inviting – daring – Labor and the Greens to back him, it would be a signal political achievement.

And if Morrison doesn’t want to, Labor, the Greens, independent MPs and conscientious LNP MPs should vote together to turn Howard’s ETS into law right away. With political will, “something different” can start now.


Updates to add that the latest Newspoll, released late Sunday, shows Morrison’s standing has taken a massive hit over the bushfires, dropping nine percentage points as preferred prime minister from 48% to 39% since the last poll in early December. Opposition leader Anthony Albanese stood at 43% – a massive reversal of Morrison’s 14 percentage point lead over the Labor leader in early December.The Conversation

Chris Wallace, ARC DECRA Fellow, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Listen to your people Scott Morrison: the bushfires demand a climate policy reboot



Scott Morrison’s response to the bushfires has been roundly criticised as being too slow and out of touch.
James Ross/AAP

Tony Walker, La Trobe University

Frank Jotzo, the director of the Centre for Climate and Energy Policy at Australian National University, has some constructive advice for Prime Minister Scott Morrison in a column today for the ABC: do not waste an opportunity to recalibrate his government’s approach on climate change.

Morrison should heed Jotzo’s suggestion that he and his cabinet need to “drop the old anti-climate change stance”. As Jotzo writes,

You’ve been politically locked into a no-action position, but the bushfires give you the reason to change […] You can make it your mission to protect the country from harm, an essential conservative cause.

Jotzo speaks with authority as one of the country’s foremost experts on climate reduction policies. He has a global reputation.




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Whether Morrison is capable of a course correction on climate change and, in the process, yield on an issue he has used to wedge his political opponents remains to be seen. However, he would be unwise to pretend that once the immediate bushfire danger passes and the smoke clears, the country will return to normal politically.

The nation will expect – indeed it will demand – that any government, conservative or Labor, face up to what is the new normal of a drying continent rendering human settlement increasingly vulnerable to extreme weather. Failure to do so will exact a heavy political price.

Scott Morrison’s holiday trip to Hawaii immediately came under fire from those who accused him of being out of touch with fire victims.
Steven Saphore/AAP

Morrison’s fallback positions are less defensible

The prime minister insists he has not denied there is a link between climate change and bushfires, but at best his responses on the subject have been evasive and self-serving politically.

Pressed on the issue, his fallback position is to say

I am sure you would also agree that no response by any one government anywhere in the world can be linked to one fire event.

That might be true, but it is hardly the point in the wider scheme of what measures might be adopted to address problems of a sluggish response to the bushfire emergency.

Morrison and others in his government might also go easy on claims that local opposition to hazard reduction burning in native forests contributed to the fires. This is a coded attacked on the Greens and is not supported by the evidence.

When in doubt, politically you might say, blame the Greens.




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Memo to Scott Morrison: people are fed up with politics proving to be a constraint on the development of a credible and sustainable climate policy that involves reasonable transitional steps to a low-carbon economy over time.

As such, he might also drop his claim that calls to reduce carbon emissions are “reckless”.

Where the prime minister is particularly vulnerable – this will be subject studied closely by any future commission of inquiry – lies in his refusal to meet a group of former emergency services leaders calling itself Emergency Leaders for Climate Change.

In April, the leader of the group, Greg Mullins, a former commissioner of NSW Fire and Rescue, wrote to Morrison warning him of the threat of “increasingly catastrophic extreme weather events”.

In September, this expert group wrote again to the prime minister asking for a meeting.

They received no constructive response.

Likewise, academic warnings about risks of climate-induced extreme weather events have been ignored.

In a March 2019 report for the Australian Strategic Policy Institute, ANU professor Robert Glasser called specifically for a national strategy to deal with climate disaster preparedness.

More than 500 Australians, about the same number who died in the Vietnam War, die each year from heat stress alone. The annual economic costs of natural disasters are projected to increase to A$39 billion by 2050, which is roughly equivalent to what the Australian government spends annually on defence.

Bear in mind Glasser’s report was written before these Christmas-New Year bushfire disasters.

We need to begin preparing now for this changing climate, by developing a national strategy that outlines exactly how we move on from business as usual and adopt a more responsible approach to climate disaster preparedness.

Demonstrating empathy, not political calculations

This bring us to issues surrounding the PM’s own leadership during the crisis.

Rosemary Williamson of the University of New England concluded a useful survey of Australian prime ministers’ responses to natural disasters last year with these words:

Australians will expect prime ministers to come and see for themselves, to demonstrate empathy and to instil confidence in recovery.

If these are the benchmarks for prime ministerial behaviour during a crisis brought on by disaster whether it is flood, fire or cyclone, Morrison has not lived up to these expectations.

First, he was – inexplicably – out of the country on holiday while uncontrollable fires began ravaging his home state of New South Wales.

Second, he has had trouble demonstrating reasonable empathy for victims of the fires.

And third, he has had difficulty accepting the Commonwealth had a shared responsibility for assisting the states in coping with the fallout from arguably the worst natural disaster in Australian history.

What has been most surprising is the time it has taken for Canberra to understand that such are the dimensions of this disaster that military assistance was necessary.

Weeks passed without the Australian Defence Force (ADF) being called out. The explanation for this delay is that states had not asked for military involvement, as if the out-of-control bushfires themselves respected state boundaries – or Commonwealth-state relations.

Coordination between Canberra and the states has improved in recent days, but in the early stages such cooperation left much to be desired.

In all of this, it is clear Morrison has laboured under a constraint of not wanting to antagonise the climate-sceptic right of his party by immediately conceding that global warming and bushfires are linked.

This would explain his tardiness in acknowledging the extent of the disaster.

Politically, he may well believe that climate remains an important point of difference between parties of left and right.




Read more:
Mr Morrison, I lost my home to bushfire. Your thoughts and prayers are not enough


Debate over climate – whether it is changing, and if so what to do about it – has become a culture wars issue over the years to the point where it has proved to be a useful political device for parties of the right.

As a politician of the right, Morrison would be reluctant to yield ground on issues to do with electricity prices that might benefit him politically in the future.

These are the political considerations that would be weighing in his calculations.

Morrison tours a scorched farm in Victoria last week.
James Ross/AAP

Charting a new course

However, the ground is shifting politically.

Polls indicate the environment is assuming greater importance among Australians. It is not far behind the economy and health in people’s concerns, according to an exhaustive poll conducted by the ANU’s 2019 Australian Election Study.

Among issues that will burden governments – both federal and state – over the next months will be the heavy costs associated with cleaning up the mess. All up, costs will run into the billions given the dimensions of destruction.

Inevitably, the bushfires will have an impact on economic activity in the December and March quarters. Growth is anaemic in any case, and may well become weaker as a consequence of reduced economic activity during the bushfire season.

Whatever economic fallout ensues, the political costs for the prime minister will continue to weigh heavily.

He would do himself a favour by advancing a credible climate and land management policy that ensures the country is better prepared when the next disaster strikes, as it surely will.The Conversation

Tony Walker, Adjunct Professor, School of Communications, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: why Mars is cold despite an atmosphere of mostly carbon dioxide



The atmosphere of Mars is thin and very dry.
NASA’s Mars Reconnaissance Orbiter, CC BY-ND

Paulo de Souza, Griffith University


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz

If tiny concentrations of carbon dioxide can hold enough heat to create a global warming impact on Earth, why is Mars cold? Its atmosphere is 95% carbon dioxide.

The recipe for the temperature of a planet’s surface has four major ingredients: atmospheric composition, atmospheric density, water content (from oceans, rivers and air humidity) and distance from the Sun. There are other ingredients, including seasonal effects or the presence of a magnetosphere, but these work more like adding flavour to a cake.

When we look at Earth, the balance of these ingredients makes our planet habitable. Changes in this balance can result in effects that can be felt on a planetary scale. This is exactly what is happening with the increase of greenhouse gases in the atmosphere of our planet.

Increased concentrations of carbon dioxide, methane, sulphur hexafluoride and other gases in the atmosphere have been raising the temperature of our planet’s surface gradually and will continue to do so for many years to come.




Read more:
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As a consequence, places covered in ice start melting and extreme weather events become more frequent. This poses a growing challenge for us to adapt to this new reality.

Small concentration, big effect

It is surprising to realise how little the concentration of carbon dioxide (CO₂) and other greenhouse gases has to change to cause such a shift in our climate. Since the 1950s, we have raised CO₂ levels in the atmosphere by a fraction of a percent, but this is already causing several changes in our climate.

This is because CO₂ represents a tiny part of Earth’s atmosphere. It is measured in parts per million (ppm) which means that for every carbon dioxide molecule there are a million others. Its concentration is just 0.041%, but even a small percentage change represents a big change in concentration.

We can tell what Earth’s atmosphere and climate were like in the distant past by analysing bubbles of ancient air trapped in ice. During Earth’s ice ages, the concentration of carbon dioxide was around 200ppm. During the warmer interglacial periods, it hovered around 280ppm, but since the 1950s, it has continued to rise relentlessly. By 2013, CO₂ levels surpassed 400ppm for the first time in recorded history.

This graph, based on samples of air bubbles fro ice cores and direct measurements of carbon dioxide, shows the rise of atmospheric carbon dioxide since the industrial revolution.
NASA, CC BY-ND

This rise represents almost a doubling in concentration, and it clear that, in the recipe for Earth’s surface temperature, carbon dioxide and other greenhouse gases are to be used in moderation.

The role of water

Like flour for a cake, water is an important ingredient of the Earth’s surface. Water makes temperature move slowly. That’s why the temperatures in tropical rainforests does not change much, but the Sahara desert is cold at night. Earth is rich in water.

Let’s have a look at our solid planets. Mercury is the closest planet to the Sun, but it has a very thin atmosphere and is not the warmest planet. Venus is very, very hot. Its atmosphere is rich in carbon dioxide (over 96%) and it is very dense.

The atmosphere of Mars is also rich in carbon dioxide (above 96%), but it is extremely thin (1% of Earth’s atmosphere), very dry and located further away from the Sun. This combination makes the planet an incredibly cold place.

The absence of water makes the temperature on Mars change a lot. The Mars exploration rovers (Spirit at Gusev Crater and Opportunity at Meridiani Planun) experienced temperatures ranging from a few degrees Celsius above zero to minus 80℃ at night: every single Martian day, known as sol.




Read more:
Curious Kids: What are some of the challenges to Mars travel?


Terraforming or terra fixing

One of the interesting challenges we face while building space payloads, like we do at Griffith University, is to build instruments that can withstand such a wide temperature range.

I love conversations about terraforming. This is the idea that we could fly to a planet with an unbreathable atmosphere and fix it by using some sort of machine to filter nasty gases and release good ones we need to survive, at the correct amount. That is a recurrent theme in many science fiction films, including Aliens, Total Recall and Red Planet.

I hope we can fix our own atmosphere on Earth and reduce our planet’s fever.The Conversation

Paulo de Souza, Professor, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.