Tag Archives: climate change

How much proof do the global warming deniers need?

“When you stare out over the wave of Weather of Mass Destruction we are unleashing, who looks crazy – the protesters, or the people who have yet to join them?”

Originally published in the UK Independent, by Johann Hari

Thank God man-made global warming was proven to be a hoax. Just imagine what the world might have looked like now if those conspiring scientists had been telling the truth. No doubt Nasa would be telling us that this year is now the hottest since humans began keeping records. The weather satellites would show that even when heat from the sun significantly dipped earlier this year, the world still got hotter. Russia’s vast forests would be burning to the ground in the fiercest drought they have ever seen, turning the air black in Moscow, killing 15,000 people, and forcing foreign embassies to evacuate. Because warm air holds more water vapour, the world’s storms would be hugely increasing in intensity and violence – drowning one fifth of Pakistan, and causing giant mudslides in China.

The world’s ice sheets would be sloughing off massive melting chunks four times the size of Manhattan. The cost of bread would be soaring across the world as heat shrivelled the wheat crops. The increased carbon dioxide in the atmosphere would be fizzing into the oceans, making them more acidic and so killing 40 per cent of the phytoplankton that make up the irreplaceable base of the oceanic food chain. The denialists would be conceding at last that everything the climate scientists said would happen – with their pesky graphs and studies and computers – came to pass.

This is all happening today, except for that final stubborn step. It’s hard to pin any one event on man-made global warming: there were occasional freak weather events before we started altering the atmosphere, and on their own, any of these events could be just another example. But they are, cumulatively, part of a plain pattern where extreme weather is occurring “with greater frequency and in many cases with greater intensity” as the temperature soars, as the US National Climatic Data Centre puts it. This is exactly what climate scientists have been warning us man-made global warming will look like, to the letter. Ashen-faced, they add that all this is coming after less than one degree of global warming since the Industrial Revolution. We are revving up for as much as five degrees more this century.

Yet as the evidence of global warming becomes ever clearer…

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Costs of the climate crisis multiply in lives and dollars

Two excellent articles in today’s Age describe the increase in natural disasters caused by global warming, and the economic cost of last year’s bushfires.

The calamities are upon us as the world warms

THEY are the extreme weather events that climate scientists have been warning about – the simultaneous catastrophes of flooding in Pakistan, wildfires in Russia and landslides in China.

Many scientists say these events are all unprecedented and that such disasters, taken together, are proof of climate change. They warn that widespread and devastating flooding will become more frequent and could be considered normal by the middle of the century.

Almost 14 million people have been affected by the torrential rains in Pakistan, and more than 1600 have died, making it a greater humanitarian disaster than the south Asian tsunami and recent earthquakes in Kashmir and Haiti combined, the United Nations says.
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In Russia, firefighters and soldiers were battling to stop wildfires from engulfing key nuclear sites while Prime Minister Vladimir Putin took to the air in a water-bombing plane to join the effort. Morgues in Moscow are overflowing as officials estimate 5000 have died in the worst heatwave in 130 years.

To continue reading click here.


Climate change will cost us all

You don’t have to be Lord Stern to see how the costs of climate change are already compounding and spiralling, out of control.

Some costs are relatively benign – such as the devaluation of waterfront properties in Byron Bay as sea levels rise – a process starting in earnest whether estate agents like it or not.

Other costs are terrible, such as the conservative $4.4 billion figure put on last year’s Black Saturday fires by the Victorian Bushfires Royal Commission, including insurance claims of $1.2 billion (property and vehicles), $1.1 billion spent by the Victorian Bushfires Reconstruction and Recovery Authority, $658 million in destroyed timber, 173 lives lost worth $645 million according to established formulae (not counting injuries) and about $593 million spent on firefighting (not counting volunteers).

Climate change features minimally in the Commission’s final report, handed down a fortnight ago. That is interesting in itself, because when he announced the inquiry the Premier, John Brumby, said everything would be on the table, including climate change.

To continue reading click here.

Gillard: moving Australia backwards on climate


Yesterday Julia Gillard announced some of the Labor Party’s climate policies.

Debate amongst the YCAN team has centred on whether these are the worst policies ever, or the second worst.

The Labor Party cannot even pretend to care about climate change now. These policies will see Australia’s emissions continue to rise rapidly while the impacts of climate change keep worsening.

In summary, the policy announcements are:

1. A green light for new coal-fired power stations and existing ones to keep polluting indefinitely

Twelve new coal-fired power stations on the drawing board around Australia have been given the go-ahead. Any new plants beyond these will be subject to “emissions standards”, which will only block brown coal developments, but not black coal.

Further, all new coal plants (the phrase “new coal plants” shouldn’t exist in and of itself as we should not be building any) will need to be “carbon capture and storage ready” – something that is completely meaningless.

Existing polluting infrastructure, such as Hazelwood Power Station remain untouched.

2. More inaction and delay

The “citizens assembly”, due to report in over 12 months is just an excuse for inaction, when urgent action is desperately needed. Community consensus on climate action has existed for years, and scientific consensus has existed well before that. We want action, not more talk!

3. Money from solar energy to go to buying petrol cars

Money will be taken away from the solar infrastructure program to fund rebates for car owners to purchase a new car if their car is older than 1995.

For further information see the Vote Climate website.

And for further analysis, Bernard Keane from Crikey has expressed it well in his piece:

Citizen Gillard abandons basic leadership on climate change

It’s hard to describe just how truly wretched Labor’s new climate change policy is. It makes the CPRS, its dog of an emissions trading scheme, look like a model of best practice. It is a spectacular failure of leadership.

Julia Gillard’s “citizens’ assembly” has effectively outsourced responsibility for climate policy to “ordinary Australians”, on whose “skills, capacity, decency and plain common sense” Gillard will rely to tell her about the community consensus on climate change. In effect it institutionalises what is already apparent — this is a Government controlled by focus group reactions.

Labor has been playing politics with climate change for three years and it hasn’t stopped. But whereas for most of that time it used climate change to damage the Coalition, now it is having to defend itself against the issue. It will only be with the political cover afforded by this nonsensical Assembly that the Government will take any action on a carbon price.

Rarely has so much goodwill and political capital been wasted on such an important issue.

The consensus the Government insists it needs the protection of before acting already exists. It’s not just in the opinion polls, which show time and time again that the majority of voters want action on climate change and supported the Government’s CPRS. In 2007, let’s not forget, both sides of politics told Australians they were going to introduce an ETS. The 2007 election endorsed a community consensus on the need for action.

Instead, in 2010, neither party will commit to any sort of carbon price mechanism for at least three years. Instead, they’re offering excuses as to why they don’t want to take action. We’ve done anything but move forward on climate action.

Gillard’s interim actions are little better. The new emissions standard she proposes won’t even apply to four coal-fired power stations being built or brought back on line currently. They may not apply to two more, the massive Mt Piper and Bayswater projects in NSW, which will together add 4% to national CO2-equivalent emissions when they come on line. Holding the baseline for the CPRS at 2008 levels won’t give electricity generators any more investment certainty when it remains unclear whether there will ever be an emissions trading scheme in Australia. Nor does it change the simple fact that State Governments continue to drive Australia into a coal-fired future.

Labor’s craven pandering to key outer-suburban electorates in its population and asylum seeker policies was bad enough. But abdicating executive responsibility for action on climate change is a new low in cynical politics, beyond the depths even reached by NSW Labor. Politicians are elected to lead. Deferring every controversial issue back to the electorate is a clumsy variant of leadership by polling and focus groups.

So blatant is Labor’s refusal to lead that it raises serious questions about its fitness for government. The only problem is that the alternative is an economically-illiterate party whose leader doesn’t believe in climate change at all, but who insists on wasting $3b on the most expensive possible means of addressing it.

What a choice, two major parties incapable of leadership and unfit to govern.

Federal Election Called – help make climate the key issue?

The election has been called and the circus begins.

Amongst the sea of spin and annoying catch phrases, it can be hard to find some substance – and sometimes, the best thing to do is to create it!

We need you to help with the Vote Climate campaign.

YCAN, together with several other local community groups will be running the Vote Climate campaign for the next five weeks.

This will be a non-partisan campaign, which aims to educate the public on the different climate policies of the three main parties.

We want to inform voters and encourage them to vote for action on climate change. With your help we can ensure that the climate crisis stays on the election agenda.

Can you help? We need volunteers to letterbox, attend stalls and attend pre-poll and polling day booths.

If you are interested in helping out then please fill out the web form here.

To donate to the Vote Climate campaign and fund the printing of the Vote Climate leaflets, you can direct transfer to the following account:
Account Name: Yarra Climate Action Now
BSB: 803 140
Account No. 23196790


Don’t let the polluters, deniers and delayers bury climate change in this election – sign up to volunteer for Vote Climate.

Take your CPRS and shove it

An absolutely classic rant by Crikey‘s Bernard Keane.

Welcome back to Parliament for the final time this year. Two more weeks of this stuff and then we’re finished for a summer that already feels like it’s been going a month. That’s assuming Anthony Albanese doesn’t keep his colleagues confined here at the end of next week, or even brings them back for another spell in December.

Wouldn’t want all those end-of-year “let’s all be best mates” speeches to get in the way of proper legislative business eh?

The job of a political journalist ?—?not of course that I would know, since according to the national broadsheet I’m not a “real journalist”, and strangely proud of it ?—?is somewhere between theatre critic and sports commentator. The main tasks of sports commentators are to tell you who’s winning and pretend something exciting is happening when it isn’t. That’s where it is closest to political journalism. Media coverage of politics is always about who’s winning and who’s losing, naturally, but the trivial and meaningless are routinely built up into events of monumental importance simply for the sake of pretending something significant is happening.

But you also need to appraise the performances of the principal actors (not to mention the ambitious walk-on players), assessing the conviction or otherwise with which they utter their lines, paying close attention to the effect not on professional observers such as oneself, who to use the immortal phrase “don’t know jack”, but the hoi polloi in the cheap seats at the back, from which vantage point scenery-chewing hammery or mindless repetition may look like the stuff of the Great Tragedians.

Once in a while, we’re reminded that this isn’t a show or a game that we’re watching. This morning the Prime Minister made an apology to the “Forgotten Generation” in the Great Hall in Parliament House. He was followed by Malcolm Turnbull. Both made heart-felt and emotional speeches, without political polish, the sort of speeches we can point to when people lament the lack of Australian political oratory. The tears and smiles and applause of those present who as children were abused in institutional care show how significant the actions of government can be, even in simply acknowledging those whose pain was ignored for so long.

This fortnight also sees some sort of climax in the emissions trading debate, another issue of more-than-usual gravity.

I don’t know about you (no, really, I don’t) but I’m utterly over the CPRS debate. It’s been a long road since early last year, when Penny Wong blithely called the Garnaut Review “one input” into the Government’s consideration, in effect spilling the beans, or giving the game away, or belling the cat, or whatever cliché takes your fancy. I’m now sick of emissions trading. Sick of Wong’s tedious droning, of Kevin Rudd’s sanctimony, of the Coalition climate denialists who make a virtue out of their own intellectual and emotional disabilities.

I’m sick of Barnaby Joyce and the National Party, so plum-stupid that they can’t even understand when the National Farmers’ Federation tells them it’d be a good idea to back the scheme. I’m sick of the rentseekers, the whingers, the sooks and Hookes, who preach the virtues of the market when it suits them but whose natural posture is of a hand stuck out, demanding assistance, and assistance in ever greater quantities, like blackmailers who just keep coming back for more.

to continue reading click here.

Take your CPRS and shove it

An absolutely classic rant by Crikey‘s Bernard Keane.

Welcome back to Parliament for the final time this year. Two more weeks of this stuff and then we’re finished for a summer that already feels like it’s been going a month. That’s assuming Anthony Albanese doesn’t keep his colleagues confined here at the end of next week, or even brings them back for another spell in December.

Wouldn’t want all those end-of-year “let’s all be best mates” speeches to get in the way of proper legislative business eh?

The job of a political journalist ?—?not of course that I would know, since according to the national broadsheet I’m not a “real journalist”, and strangely proud of it ?—?is somewhere between theatre critic and sports commentator. The main tasks of sports commentators are to tell you who’s winning and pretend something exciting is happening when it isn’t. That’s where it is closest to political journalism. Media coverage of politics is always about who’s winning and who’s losing, naturally, but the trivial and meaningless are routinely built up into events of monumental importance simply for the sake of pretending something significant is happening.

But you also need to appraise the performances of the principal actors (not to mention the ambitious walk-on players), assessing the conviction or otherwise with which they utter their lines, paying close attention to the effect not on professional observers such as oneself, who to use the immortal phrase “don’t know jack”, but the hoi polloi in the cheap seats at the back, from which vantage point scenery-chewing hammery or mindless repetition may look like the stuff of the Great Tragedians.

Once in a while, we’re reminded that this isn’t a show or a game that we’re watching. This morning the Prime Minister made an apology to the “Forgotten Generation” in the Great Hall in Parliament House. He was followed by Malcolm Turnbull. Both made heart-felt and emotional speeches, without political polish, the sort of speeches we can point to when people lament the lack of Australian political oratory. The tears and smiles and applause of those present who as children were abused in institutional care show how significant the actions of government can be, even in simply acknowledging those whose pain was ignored for so long.

This fortnight also sees some sort of climax in the emissions trading debate, another issue of more-than-usual gravity.

I don’t know about you (no, really, I don’t) but I’m utterly over the CPRS debate. It’s been a long road since early last year, when Penny Wong blithely called the Garnaut Review “one input” into the Government’s consideration, in effect spilling the beans, or giving the game away, or belling the cat, or whatever cliché takes your fancy. I’m now sick of emissions trading. Sick of Wong’s tedious droning, of Kevin Rudd’s sanctimony, of the Coalition climate denialists who make a virtue out of their own intellectual and emotional disabilities.

I’m sick of Barnaby Joyce and the National Party, so plum-stupid that they can’t even understand when the National Farmers’ Federation tells them it’d be a good idea to back the scheme. I’m sick of the rentseekers, the whingers, the sooks and Hookes, who preach the virtues of the market when it suits them but whose natural posture is of a hand stuck out, demanding assistance, and assistance in ever greater quantities, like blackmailers who just keep coming back for more.

to continue reading click here.

Climate Basics Explained: How hot is too hot?

Today the world’s average temperature is just under one degree Celsius above what it was in pre-industrial times. Some scientists are saying that with the current level of greenhouse gases in the atmosphere, a two degree rise is locked in unless we can reduce emissions to almost zero and actively remove carbon from the atmosphere. It is also likely that on current emissions trajectories, we will reach a six degree rise by 2100.

The Australian Federal Government and most governments around the world have yet to officially set what temperature rise they believe is adequately safe. Many unofficially subscribe to the aim of keeping temperature rise to two degrees or below. However, the most recent science indicates that this may be too high and trigger feedback loops that result in more temperature rises outside of humanity’s control.

So what do these temperature rises mean in reality?

The following summary has been taken from two sources. Mark Lynas’ article in The Guardian and David Spratt’s presentation at the Moreland Climate Group‘s recent climate debate. We will count down from six to one.

Six Degrees and Above
Danger of “runaway warming”, perhaps spurred by the release of oceanic methane hydrates. Could the surface of the Earth become like Venus, entirely uninhabitable? Most sea life is dead. Human refuges are now confined entirely to highland areas and the polar regions. The human population is drastically reduced. Perhaps 90% of species become extinct, rivalling the worst mass extinctions in the Earth’s 4.5 billion-year history.

Five Degrees
Global average temperatures are now hotter than for 50 million years. At this time breadfruit trees grew on the coast of Greenland, while the Arctic Ocean saw water temperatures of 20 degrees Celsius. There was no ice at either pole (today that means a 70-metre sea-level rise), and much of the world would have been desertified.

At five degrees, most of the topics, sub-tropics and even lower mid-latitudes are too hot to be inhabitable. Sea level rise is now sufficiently rapid that coastal cities across the world are largely abandoned.

Prof. Hans Joachim Schellnuhuber, Director of the Potsdam Institute and adviser to the European Union and to the German Chancellor, told the Copenhagen science conference in March that a rise to 5–6 degrees Celsius above preindustrial levels would reduce “the carrying capacity of the planet (to) below 1 billion people”.

Four Degrees
A tipping point sees massive amounts of methane – a potent greenhouse gas – released by melting Siberian permafrost, further boosting global warming and making further human action to mitigate emissions futile. Much human habitation in southern Europe, north Africa, the Middle East and other sub-tropical areas is rendered unviable due to excessive heat and drought. Deserts are spreading in Italy, Spain, Greece and Turkey. The focus of civilisation moves towards the poles, where temperatures remain cool enough for crops, and rainfall – albeit with severe floods – persists. All sea ice is gone from both poles; mountain glaciers are gone from the Andes, Alps and Rockies, with severe water supply implications for these areas.

Three Degrees
3 degrees Celsius is the cap effectively being advocated by Australia’s Labor government. Labor policy is a 60 per cent reduction in Australian emissions by 2050. Sir Nicholas Stern says explicitly that for developed nations this is a 3 degrees Celsius target, telling the National Press Club in Canberra it would be “a very good idea if all rich countries, including Australia, set themselves a target for 2050 of at least 60 per cent emissions reductions” and this would leave us with “roughly a ?fty-?fty chance of being either side of 3 degrees above pre-industrial times”.

This is the target that both Stern and Garnaut advocated, but Stern now says that “We haven’t seen 3 degrees Celsius for a few million years, and we don’t know what that looks like”. But from the Pliocene 3 million years ago we know what a 3 degrees Celsius world would likely be: a northern hemisphere free of glaciers and icesheets, where beech trees grew in the Transantarctic mountains, sea levels were 25 metres higher, and probably permanent El Nino conditions.

Glacier and snow-melt in the world’s mountain chains will deplete freshwater flows to downstream cities and agricultural land. Most affected are California, Peru, Pakistan and China. Global food production is under threat as key breadbaskets in Europe, Asia and the United States suffer drought, and heatwaves outstrip the tolerance of crops. The Gulf Stream current declines significantly. Cooling in Europe is unlikely due to global warming, but oceanic changes alter weather patterns and lead to higher than average sea level rise in the eastern US and UK.

NASA climate chief Dr James Hansen has warned that a 3 degrees Celsius warming “threatens even greater calamity, because it could unleash positive feedbacks such as melting of frozen methane in the Arctic, as occurred 55 million years ago, when more than 90 per cent of species on Earth went extinct”. Hitting three degrees may mean that we are not able to stop there.

Two Degrees
2 degrees Celsius has been a target of convenience in international negotiations, but is now losing consensus as the politicians head to 3 and 4 degrees Celsius, and the scientists towards zero.

To have a 2 in 3 chance of holding to 2 degrees Celsius, atmospheric carbon needs to be held to 400ppm CO2e (carbon dioxide equivalent) and that requires a global reduction is emissions of 80% by 2050 (over 1990) and negative emissions after 2070. For Australia, a 2 degrees Celsius target means a more than 95% cut by 2050.

A rise of 2 degrees Celsius over pre-industrial temperatures will initiate large climate feedbacks in the oceans, on ice-sheets, and on the tundra, taking the Earth well past signi?cant tipping points. Likely impacts include large-scale disintegration of the Greenland and West Antarctic ice-sheet; the extinction of an estimated 15– 40 per cent of plant and animal species; dangerous ocean acidi?cation; increasing methane release; substantial soil and ocean carbon-cycle feedbacks; and widespread drought and deserti?cation in Africa, Australia, Mediterranean Europe, and the western USA.

Hansen told the US Congress last year that: “We have reached a point of planetary emergency… climate is nearing dangerous tipping points. Elements of a perfect storm, a global cataclysm, are assembled… the oft-stated goal to keep global warming less than +2 degrees Celsius is a recipe for global disaster, not salvation.”

Summer heatwaves such as that in Europe in 2003, which killed 30,000 people, become annual events. Extreme heat sees temperatures reaching the low 40s Celsius in southern England. Amazon rainforest crosses a “tipping point” where extreme heat and lower rainfall makes the forest unviable – much of it burns and is replaced by desert and savannah. Dissolved CO2 turns the oceans increasingly acidic, destroying remaining coral reefs and wiping out many species of plankton which are the basis of the marine food chain. Several metres of sea level rise is now inevitable.

One Degree
Today at just less than 1 degree Celsius of global warming we are witnessing of the destruction of the Arctic ecosystem. Eight million square kilometres of sea ice is disappearing fast each summer and may be entirely gone within a few years. Already 80% by volume of summer sea-ice has been lost, and regional warming of up to 5 degrees Celsius may have already pushed the Greenland ice-sheet (eventual sea-level rise of 7 metres) past its tipping point.

At less than 1 degree Celsius there is more frequent and intense heatwaves, ongoing drought around the Mediterranean and in Australia, sub-Saharan Africa and the western US, and the swift retreat of river-feeding mountain glaciers. The eastern Amazon is drying (some tributaries ran dry in the 2005 drought), low-lying island states are on the edge of a precipice, as are coral reefs. Britain’s Hadley Centre calculates that warming of just 1C would eliminate fresh water from a third of the world’s land surface by 2100.

It is obvious from these predictions that we need to reduce emissions and draw down carbon from the atmosphere, to get warming back down to as close to zero as possible. We need to make politically possible what is scientifically necessary.

Climate Basics Explained: How hot is too hot?

Today the world’s average temperature is just under one degree Celsius above what it was in pre-industrial times. Some scientists are saying that with the current level of greenhouse gases in the atmosphere, a two degree rise is locked in unless we can reduce emissions to almost zero and actively remove carbon from the atmosphere. It is also likely that on current emissions trajectories, we will reach a six degree rise by 2100.

The Australian Federal Government and most governments around the world have yet to officially set what temperature rise they believe is adequately safe. Many unofficially subscribe to the aim of keeping temperature rise to two degrees or below. However, the most recent science indicates that this may be too high and trigger feedback loops that result in more temperature rises outside of humanity’s control.

So what do these temperature rises mean in reality?

The following summary has been taken from two sources. Mark Lynas’ article in The Guardian and David Spratt’s presentation at the Moreland Climate Group‘s recent climate debate. We will count down from six to one.

Six Degrees and Above
Danger of “runaway warming”, perhaps spurred by the release of oceanic methane hydrates. Could the surface of the Earth become like Venus, entirely uninhabitable? Most sea life is dead. Human refuges are now confined entirely to highland areas and the polar regions. The human population is drastically reduced. Perhaps 90% of species become extinct, rivalling the worst mass extinctions in the Earth’s 4.5 billion-year history.

Five Degrees
Global average temperatures are now hotter than for 50 million years. At this time breadfruit trees grew on the coast of Greenland, while the Arctic Ocean saw water temperatures of 20 degrees Celsius. There was no ice at either pole (today that means a 70-metre sea-level rise), and much of the world would have been desertified.

At five degrees, most of the topics, sub-tropics and even lower mid-latitudes are too hot to be inhabitable. Sea level rise is now sufficiently rapid that coastal cities across the world are largely abandoned.

Prof. Hans Joachim Schellnuhuber, Director of the Potsdam Institute and adviser to the European Union and to the German Chancellor, told the Copenhagen science conference in March that a rise to 5–6 degrees Celsius above preindustrial levels would reduce “the carrying capacity of the planet (to) below 1 billion people”.

Four Degrees
A tipping point sees massive amounts of methane – a potent greenhouse gas – released by melting Siberian permafrost, further boosting global warming and making further human action to mitigate emissions futile. Much human habitation in southern Europe, north Africa, the Middle East and other sub-tropical areas is rendered unviable due to excessive heat and drought. Deserts are spreading in Italy, Spain, Greece and Turkey. The focus of civilisation moves towards the poles, where temperatures remain cool enough for crops, and rainfall – albeit with severe floods – persists. All sea ice is gone from both poles; mountain glaciers are gone from the Andes, Alps and Rockies, with severe water supply implications for these areas.

Three Degrees
3 degrees Celsius is the cap effectively being advocated by Australia’s Labor government. Labor policy is a 60 per cent reduction in Australian emissions by 2050. Sir Nicholas Stern says explicitly that for developed nations this is a 3 degrees Celsius target, telling the National Press Club in Canberra it would be “a very good idea if all rich countries, including Australia, set themselves a target for 2050 of at least 60 per cent emissions reductions” and this would leave us with “roughly a ?fty-?fty chance of being either side of 3 degrees above pre-industrial times”.

This is the target that both Stern and Garnaut advocated, but Stern now says that “We haven’t seen 3 degrees Celsius for a few million years, and we don’t know what that looks like”. But from the Pliocene 3 million years ago we know what a 3 degrees Celsius world would likely be: a northern hemisphere free of glaciers and icesheets, where beech trees grew in the Transantarctic mountains, sea levels were 25 metres higher, and probably permanent El Nino conditions.

Glacier and snow-melt in the world’s mountain chains will deplete freshwater flows to downstream cities and agricultural land. Most affected are California, Peru, Pakistan and China. Global food production is under threat as key breadbaskets in Europe, Asia and the United States suffer drought, and heatwaves outstrip the tolerance of crops. The Gulf Stream current declines significantly. Cooling in Europe is unlikely due to global warming, but oceanic changes alter weather patterns and lead to higher than average sea level rise in the eastern US and UK.

NASA climate chief Dr James Hansen has warned that a 3 degrees Celsius warming “threatens even greater calamity, because it could unleash positive feedbacks such as melting of frozen methane in the Arctic, as occurred 55 million years ago, when more than 90 per cent of species on Earth went extinct”. Hitting three degrees may mean that we are not able to stop there.

Two Degrees
2 degrees Celsius has been a target of convenience in international negotiations, but is now losing consensus as the politicians head to 3 and 4 degrees Celsius, and the scientists towards zero.

To have a 2 in 3 chance of holding to 2 degrees Celsius, atmospheric carbon needs to be held to 400ppm CO2e (carbon dioxide equivalent) and that requires a global reduction is emissions of 80% by 2050 (over 1990) and negative emissions after 2070. For Australia, a 2 degrees Celsius target means a more than 95% cut by 2050.

A rise of 2 degrees Celsius over pre-industrial temperatures will initiate large climate feedbacks in the oceans, on ice-sheets, and on the tundra, taking the Earth well past signi?cant tipping points. Likely impacts include large-scale disintegration of the Greenland and West Antarctic ice-sheet; the extinction of an estimated 15– 40 per cent of plant and animal species; dangerous ocean acidi?cation; increasing methane release; substantial soil and ocean carbon-cycle feedbacks; and widespread drought and deserti?cation in Africa, Australia, Mediterranean Europe, and the western USA.

Hansen told the US Congress last year that: “We have reached a point of planetary emergency… climate is nearing dangerous tipping points. Elements of a perfect storm, a global cataclysm, are assembled… the oft-stated goal to keep global warming less than +2 degrees Celsius is a recipe for global disaster, not salvation.”

Summer heatwaves such as that in Europe in 2003, which killed 30,000 people, become annual events. Extreme heat sees temperatures reaching the low 40s Celsius in southern England. Amazon rainforest crosses a “tipping point” where extreme heat and lower rainfall makes the forest unviable – much of it burns and is replaced by desert and savannah. Dissolved CO2 turns the oceans increasingly acidic, destroying remaining coral reefs and wiping out many species of plankton which are the basis of the marine food chain. Several metres of sea level rise is now inevitable.

One Degree
Today at just less than 1 degree Celsius of global warming we are witnessing of the destruction of the Arctic ecosystem. Eight million square kilometres of sea ice is disappearing fast each summer and may be entirely gone within a few years. Already 80% by volume of summer sea-ice has been lost, and regional warming of up to 5 degrees Celsius may have already pushed the Greenland ice-sheet (eventual sea-level rise of 7 metres) past its tipping point.

At less than 1 degree Celsius there is more frequent and intense heatwaves, ongoing drought around the Mediterranean and in Australia, sub-Saharan Africa and the western US, and the swift retreat of river-feeding mountain glaciers. The eastern Amazon is drying (some tributaries ran dry in the 2005 drought), low-lying island states are on the edge of a precipice, as are coral reefs. Britain’s Hadley Centre calculates that warming of just 1C would eliminate fresh water from a third of the world’s land surface by 2100.

It is obvious from these predictions that we need to reduce emissions and draw down carbon from the atmosphere, to get warming back down to as close to zero as possible. We need to make politically possible what is scientifically necessary.