Tag Archives: CO2

Finally! The Greenland deglaciation paradox sorted.

from ScienceDaily

Bo Vinther prepares an ice core for visual inspection. Credit: Photograph by Christian Morel

A new study of three ice cores from Greenland documents the warming of the large ice sheet at the end of the last ice age — resolving a long-standing paradox over when that warming occurred.

 Large ice sheets covered North America and northern Europe some 20,000 years ago during the coldest part of the ice age, when global average temperatures were about four degrees Celsius (or seven degrees Fahrenheit) colder than during pre-industrial times. And then changes in Earth’s orbit around the sun increased the solar energy reaching Greenland. Beginning some 18,000 years ago, release of carbon from the deep ocean led to a graduate rise in atmospheric carbon dioxide (CO2).

Yet past analysis of ice cores from Greenland did not show any warming response as would be expected from an increase in CO2 and solar energy flux, the researchers note.

In this new study, funded by the National Science Foundation and published this week in the journal Science, scientists reconstructed air temperatures by examining ratios of nitrogen isotopes in air trapped within the ice instead of isotopes in the ice itself, which had been used in past studies.

Not only did the new analysis detect significant warming in response to increasing atmospheric CO2, it documents a warming trend at a rate closely matching what climate change models predict should have happened as Earth shifted out of its ice age, according to lead author Christo Buizert, a postdoctoral researcher at Oregon State University and lead author on the Science article.

“The Greenland isotope records from the ice itself suggest that temperatures 12,000 years ago during the so-called Younger Dryas period near the end of the ice age were virtually the same in Greenland as they were 18,000 years ago when much of the northern hemisphere was still covered in ice,” Buizert said. “That never made much sense because between 18,000 and 12,000 years ago atmospheric CO2 levels rose quite a bit.”

“But when you reconstruct the temperature history using nitrogen isotope ratios as a proxy for temperature, you get a much different picture,” Buizert pointed out. “The nitrogen-based temperature record shows that by 12,000 years ago, Greenland temperatures had already warmed by about five degrees (Celsius), very close to what climate models predict should have happened, given the conditions.”

Reconstructing temperatures by using water isotopes provides useful information about when temperatures shift but can be difficult to calibrate because of changes in the water cycle, according to Edward Brook, an Oregon State paleoclimatologist and co-author on the Science study.

“The water isotopes are delivered in Greenland through snowfall and during an ice age, snowfall patterns change,” Brook noted. “It may be that the presence of the giant ice sheet made snow more likely to fall in the summer instead of winter, which can account for the warmer-than-expected temperatures because the snow records the temperature at the time it fell.”

In addition to the gradual warming of five degrees (C) over a 6,000-year period beginning 18,000 years ago the study investigated two periods of abrupt warming and one period of abrupt cooling documented in the new ice cores. The researchers say their leading hypothesis is that all three episodes are tied to changes in the Atlantic meridional overturning circulation (AMOC), which brings warm water from the tropics into the high northern latitudes.

The first episode caused a jump in Greenland’s air temperatures of 10-15 degrees (C) in just a few decades beginning about 14,700 years ago. An apparent shutdown of the AMOC about 12,800 years ago caused an abrupt cooling of some 5-9 degrees (C), also over a matter of decades.

When the AMOC was reinvigorated again about 11,600 years ago, it caused a jump in temperatures of 8-, 11 degrees (C), which heralded the end of the ice age and the beginning of the climatically warm and stable Holocene period, which allowed human civilization to develop.

“For these extremely abrupt transitions, our data show a clear fingerprint of AMOC variations, which had not yet been established in the ice core studies,” noted Buizert, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Other evidence for AMOC changes exists in the marine sediment record and our work confirms those findings.”

In their study, the scientists examined three ice cores from Greenland and looked at the gases trapped inside the ice for changes in the isotopic ration of nitrogen, which is very sensitive to temperature change. They found that temperatures in northwest Greenland did not change nearly as much as those in southeastern Greenland — closest to the North Atlantic — clearly suggesting the influence of the AMOC.

“The last deglaciation is a natural example of global warming and climate change,” Buizert said. “It is very important to study this period because it can help us better understand the climate system and how sensitive the surface temperature is to atmospheric CO2.”

“The warming that we observed in Greenland at the end of the ice age had already been predicted correctly by climate models several years ago,” Buizert added. “This gives us more confidence that these models also predict future temperatures correctly.”

 

From Science

Greenland deglaciation puzzles

Louise Claire Sime, British Antarctic Survey, High Cross, Cambridge, CB23 7PP, UK.

About 23,000 years ago, the southern margins of the great Northern Hemisphere ice sheets across Europe and North America began to melt. The melt rate accelerated ∼20,000 years ago, and global sea level eventually rose by ∼130 m as meltwater flowed into the oceans. Ice cores from the Greenland and Antarctic ice sheets show the rise in atmospheric CO2 concentrations that accompanied this shift in global ice volume and climate. However, discrepancies in the temperature reconstructions from these cores have raised questions about the long-term relationship between atmospheric CO2 concentrations and Arctic temperature. On page 1177 of this issue, Buizert et al. (1) report temperature reconstructions from three locations on the Greenland ice sheet that directly address these problems.

Abstract

Greenland ice core water isotopic composition (δ18O) provides detailed evidence for abrupt climate changes but is by itself insufficient for quantitative reconstruction of past temperatures and their spatial patterns. We investigate Greenland temperature evolution during the last deglaciation using independent reconstructions from three ice cores and simulations with a coupled ocean-atmosphere climate model. Contrary to the traditional δ18O interpretation, the Younger Dryas period was 4.5° ± 2°C warmer than the Oldest Dryas, due to increased carbon dioxide forcing and summer insolation. The magnitude of abrupt temperature changes is larger in central Greenland (9° to 14°C) than in the northwest (5° to 9°C), fingerprinting a North Atlantic origin. Simulated changes in temperature seasonality closely track changes in the Atlantic overturning strength and support the hypothesis that abrupt climate change is mostly a winter phenomenon.

 

Original Science Daily article here

Science paper here

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What the scientists really think about climate change.

 

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Growing up in the 1970’s and 1980’s on a farm in a small town, I spent most of my spare time outside playing riding around on my bike with my friends, and also helping out in the family business. I never really watched a lot of television but when I did I loved to watch The Curiosity Show with Rob and Dean. For those unfamiliar, here is a random clip from one of their shows.

It was this show that really got me interested in Science. Rob and Dean had a way of making science exciting and they did this through effective communication. They could explain what they were doing and make it exciting and relevant. What young kid watching the above example wouldn’t get excited about blowing the lid off something? All that nitrogen gas was also cool and creepy.

The other show I never missed was Why is it So? with Professor Julius Sumner Miller. Here was a guy who could have been typecast into any Hollywood movie or television drama as a stereotypical nutty professor. He was brilliant, not so much because he could communicate effectively (which he obviously could) but because he was so passionate about science and self-assured and this really came through. I was left in no doubt about how he was feeling at any given moment. Recently I have become re-acquainted with Miller and have spent many hours on YouTube watching grainy copies of Demonstrations in Physics. One of my favourites was his lecture on Bernoulli. It is classic Sumner Miller and it will leave you in no doubt about his passion for physics and ability to effectively communicate. I particularly enjoy his language. His “common enchantment” is on show.

Fast forward 30 something years to today and one of my biggest laments in science is the unwillingness of scientists to really express their personal feelings about the science they are doing. Scientists are for some reason almost expected to maintain the dispassion they apply to the scientific method throughout all aspects of their life or at least to keep their personal feelings out of the public eye, especially if they are negative. Perhaps I’m generalising a bit here but it is the impression I have gotten over the years, especially where climate science is concerned. I’m not a climate scientist and I am really pissed off about the lack of action. I am really pissed off by the bullshit “arguments” put up by non-experts. I am pissed off with the media giving false balance to these morons. When I see charlatans from fossil fuel funded think-tanks on my television I want to throw something. I will throw my hands up in the air and wonder why the climate scientists are not being heard? Why aren’t they putting a human face on their findings? I know they are all passionate about their science and they have to be tearing their hair out at the prospect of what we are doing to our world.

Well, with our new dysfunctional, fossil fuel funded, climate change denying, anti-science, fossil-filled conservative government destroying renewable energy initiatives, dismantling key climate institutions, removing the only demonstrable method of reducing CO2 emissions, dishing out corporate welfare to billionaire miners and removing environmental impediments to their business interests, it seems some Australian climate experts are finally putting their thoughts in the public domain.  Joe Duggan, a master’s student in science communication at the Australian National University’s Centre for the Public Awareness of Science has asked the experts to write down their thoughts and has put them on his blog. It makes for some sobering reading.

Check it out here.

 

 

 

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100 000 000 people will die by 2030 if the world fails to act on climate change

from Reuters by NINA CHESTNEY

Rain clouds gather as a skytrain passes the victory monument in Bangkok September 25, 2012. REUTERS/Chaiwat Subprasom

Rain clouds gather as a skytrain passes the victory monument in Bangkok September 25, 2012. Credit: Reuters/Chaiwat Subprasom

More than 100 million people will die and global economic growth will be cut by 3.2 percent of gross domestic product (GDP) by 2030 if the world fails to tackle climate change, a report commissioned by 20 governments said on Wednesday.

As global average temperatures rise due to greenhouse gas emissions, the effects on the planet, such as melting ice caps, extreme weather, drought and rising sea levels, will threaten populations and livelihoods, said the report conducted by humanitarian organisation DARA.

It calculated that five million deaths occur each year from air pollution, hunger and disease as a result of climate change and carbon-intensive economies, and that toll would likely rise to six million a year by 2030 if current patterns of fossil fuel use continue.

More than 90 percent of those deaths will occur in developing countries, said the report that calculated the human and economic impact of climate change on 184 countries in 2010 and 2030. It was commissioned by the Climate Vulnerable Forum, a partnership of 20 developing countries threatened by climate change.

“A combined climate-carbon crisis is estimated to claim 100 million lives between now and the end of the next decade,” the report said.

It said the effects of climate change had lowered global output by 1.6 percent of world GDP, or by about $1.2 trillion a year, and losses could double to 3.2 percent of global GDP by 2030 if global temperatures are allowed to rise, surpassing 10 percent before 2100.

It estimated the cost of moving the world to a low-carbon economy at about 0.5 percent of GDP this decade.

COUNTING THE COST

British economist Nicholas Stern told Reuters earlier this year investment equivalent to 2 percent of global GDP was needed to limit, prevent and adapt to climate change. His report on the economics of climate change in 2006 said an average global temperature rise of 2-3 degrees Celsius in the next 50 years could reduce global consumption per head by up to 20 percent.

Temperatures have already risen by about 0.8 degrees Celsius above pre-industrial times. Almost 200 nations agreed in 2010 to limit the global average temperature rise to below 2C (3.6 Fahrenheit) to avoid dangerous impacts from climate change.

But climate scientists have warned that the chance of limiting the rise to below 2C is getting smaller as global greenhouse gas emissions rise due to burning fossil fuels.

The world’s poorest nations are the most vulnerable as they face increased risk of drought, water shortages, crop failure, poverty and disease. On average, they could see an 11 percent loss in GDP by 2030 due to climate change, DARA said.

“One degree Celsius rise in temperature is associated with 10 percent productivity loss in farming. For us, it means losing about 4 million metric tonnes of food grain, amounting to about $2.5 billion. That is about 2 percent of our GDP,” Bangladesh’s Prime Minister Sheikh Hasina said in response to the report.

“Adding up the damages to property and other losses, we are faced with a total loss of about 3-4 percent of GDP.”

Even the biggest and most rapidly developing economies will not escape unscathed. The United States and China could see a 2.1 percent reduction in their respective GDPs by 2030, while India could experience a more than 5 percent loss.

The full report is available at: daraint.org/

 

Original story here

 

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800000 years of atmospheric CO2

This was uploaded a few days ago and represents the latest data on CO2 levels upuntil January 2014. The physics of how CO2 acts as a greenhouse gas is well understood and has been for many years. Understanding this makes the following video all the more concerning.

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Ocean Acidification – the other big CO2 problem

from oceanacidification.net

Ocean Acidification is not a peripheral climate issue, it is the other CO2 challenge. The world’s leading marine scientists are warning us that our current rates of carbon emissions are making our oceans more acidic. This is happening so fast that it poses a serious threat to biodiversity and marine life.

Left unchecked, Ocean Acidification could destroy all our coral reefs by as early as 2050. It also has the potential to disrupt other ocean ecosystems, fisheries, habitats, and even entire oceanic food chains.

For resources and everything you need to know about ocean acidification go here.

 

 

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Palmer’s revolt leaves Abbott with no climate policy

by James Wight at Precarious Climate

Australian coal mining billionaire politician Clive Palmer announced on Tuesday that his party’s Senators will vote against the Emissions Reduction Fund (ERF), the Abbott government’s proposed replacement for the carbon price it wants to repeal. Palmer wants the promised ERF funding to be redirected to pensions, and says he is even prepared to block budget bills if necessary.

Undeterred, the Government has pressed on, releasing the ERF White Paper on the eve of Anzac Day (in the tradition of the Green Paper released on the last day before Xmas). But with Palmer offside, ERF legislation will struggle to find any support from non-government Senators.

Labor and the Greens oppose the ERF as too weak. The Motoring Enthusiasts will vote with Palmer United. The Liberal Democrats, Family First, and Democratic Labor are unlikely to support any climate policy because they don’t believe the problem is real. And independent Nick Xenophon won’t support the ERF unamended. That makes up to 43 votes against the ERF, and only 38 votes are needed to block legislation. So it is very unlikely that Abbott will be unable to pass the legislation. This leaves Abbott with almost no climate policy (except the soon-to-be-neutered Renewable Energy Target, and some other bits and pieces that won’t achieve much).

Whether or not Abbott is able to implement the ERF probably won’t make much difference to emissions, because the ERF is a laughable scheme which will pay polluters to (in theory) voluntarily act to avoid emitting CO2 they otherwise would have emitted. I’ve written previously about 21 reasons why Abbott’s policy won’t work, including some issues which have received little attention – and almost all of what I said then remains essentially accurate.

Another thing which will make no difference is the “safeguard mechanism”, the penalty for polluters who exceed their baseline emissions levels under the ERF. Too many people are withholding judgment until the details are announced, when in fact we already know all we need to know. All ERF policy documents have made clear that both the fund itself and the supposed safeguard will allow emissions to increase wherever production increases (even if historical absolute baselines are used they will not apply to new companies or significant business expansion). In other words, the ERF is designed to cut emissions intensity (emissions per economic output), not absolute emissions. This is pointless as emissions intensity will fall automatically even if emissions rise; the problem is that those efficiency gains are being cancelled out by the exponential growth of the fossil fuel economy. The Government is budgeting zero revenue from the safeguard mechanism because they know it will never come into play.

What’s new in the White Paper?

  • The policy objective, which used to be to meet Australia’s inadequate emissions target of 5% below 2000 by 2020, is now merely “to reduce emissions at lowest cost over the period to 2020, and make a contribution towards Australia’s 2020 emissions reduction target”.
  • The White Paper contains endless impenetrable text about how the Government will design emissions-reduction-verifying “methods” (through consultation with polluters), but there is still no reason to think these methods will have any validity. We do learn that methods will be reviewed by an “independent expert committee” called the Emissions Reduction Assurance Committee, which would be reassuring if the Abbott government didn’t have a history of appointing ideological allies to such panels.
  • ERF funding is still capped for the first four years, and it sounds like beyond that funding will be decided in each budget. Again this is hardly reassuring, as every climate program’s funding seems to diminish over time.
  • Polluters who fail to deliver emissions cuts contracted by the government must “make good” by purchasing offsets from other domestic companies. I cannot find any mention of earlier proposals to allow international offsets, though business groups continue to lobby for this.
  • The 2015 review of the ERF will focus merely on operational elements.

A few journalists have made some half-hearted attempts to get more information out of Environment Minister Greg Hunt, but whenever he is asked a question about the ERF he just starts rabbiting on about how bad the carbon price was. Meanwhile, we’re hearing more and more from government members and advisors that climate change isn’t real after all. In the last fortnight, Attorney-General George Brandis, government backbencher George Christensen, and Abbott’s business advisor Maurice Newman have all challenged the science of climate change.

Perhaps they’re ramping up their attacks on science because they realize the ERF is losing credibility. Because there is one way in which it does matter whether the ERF goes ahead. If it proceeds, Abbott will be able to use it to support the talking point that his government has a policy on climate change, reassuring voters who are concerned about climate change but nervous about the alleged costs of a carbon price. But if the ERF founders, and Abbott succeeds in his overall agenda of climate deregulation, then he will have no significant policy to greenwash his government. And as the hot summers keep coming, there’ll be nothing to stop those concerned voters from becoming alarmed.

Read the original and check out all the other excellent articles at Precarious Climate here.

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Climate change is already changing the Australian landscape

from David Donaldson at the Guardian

Climate zones along the coast of southeastern Australia have already moved south by around 350km. Those fluctuations are also altering the way rural communities live.

tree guardian

I was in high school when crested pigeons started showing up at the farm where I grew up. Situated in a flat, pastoral corner of southwest Victoria, the pointy-haired birds first seemed out of place – a budding wildlife enthusiast, I’d previously only seen photos of them in the desert.

But thanks to the millennium drought – which became progressively worse from around the time I started primary school until my final year of high school – the crested pigeons had obviously decided southwest Victoria was now sufficiently dehydrated for them to take up residence. Though the drought ended several years ago, the pigeons are now a permanent fixture on the farm; I hear their distinctive whirring sound every time I go back to visit.

The same thing happened with galahs when my father was young. The pink and grey cockatoos flew in from the north during the 1965-68 drought and have never left. Other birds, such as the charismatic grey fantail, have changed their migratory behaviour in recent years as winters become milder and shorter, as have countless species right around the world.

It’s not just the wildlife that’s changing. The hotter, drier climate gradually imposing itself on southeastern Australia is forcing changes to agriculture. In southwest Victoria, this means it’s becoming harder to produce the beef and wool my father grew when I was a child. Cereal cropping, which uses less water and creates fewer jobs, is becoming more popular.

A Crested Pigeon.
A Crested Pigeon. Photograph: Ed Dunens/Flickr

Old European trees in gardens and town centres are dying in the long, waterless summers. Aquifers are becoming harder to access as runoff remains low, while decreasing autumn precipitation is leading to a shorter growing season. Frosts are becoming less common, though clear skies, which allow heat to escape at night-time, mean minimum temperatures are not increasing at the same rate as maximums.

The changes are also altering the way rural communities live. The drought in particular had a huge and traumatic effect. Livestock previously had to be shot when feed and water ran out. Many workers ended up leaving farming because it was just too hard. Tragically, the suicide rate among farmers spiked during the final years as entire livelihoods were reduced to dust. Though drought is a recurrent theme of the Australian landscape, this one was especially long and harsh – and the research suggests such phenomena will only become more common.

As the IPCC’s fifth assessment report has reiterated, climate change is not merely a beast of the future – it’s been happening for a while. Victoria’s average annual mean temperature has increased by almost 0.9°C over the past century, around the same as the rest of Australia. Although rainfall is more variable, droughts are becoming longer and drier. Record high temperatures are regularly broken, while record lows are becoming harder to find.

Climate zones along the coast of southeastern Australia have already moved south by around 350km. Those on the northeast coast have shifted around 200km. Fish species are travelling further south than before. Long-spined sea urchins, previously found only as far south as southern NSW, have been caught in eastern Tasmania. Other organisms have specific, geographically-bound ranges that do not allow them to move, and will find it difficult to adapt to warmer seas.

Terrestrial animals will increasingly face the same problem. Our national parks are poorly connected in large areas of Australia, meaning many creatures will be unable to migrate as temperatures increase. Some animals escaping monsoonal northern Australia will find it difficult to survive in drier inland areas. Alpine animals, such as the Leadbeater’s Possum, will be especially challenged as thin snowfall and bigger bushfires cause their habitat to disappear.

But while the outlook is concerning for agricultural production and downright terrible for our natural habitat, there are a few glimmers of hope. It’s reassuring that, despite the acrimony surrounding climate politics at a national level, there are plenty of community groups and governmental bodies conducting important research into how we deal with a hotter, drier Australia. While politicians and vested interests have muddied the waters of public opinion for strong action to stop climate change, pragmatism based on evidence is leading progress in adaptation and mitigation.

Though it may be politically conservative, southwest Victoria is no exception. In 2013 for example, Moyne shire released an extensive coastal hazard assessment report for popular holiday town Port Fairy, finding that several hundred buildings would be at risk of inundation by seawater as ocean levels rise.

Individual farmers, landcare groups and catchment management authorities are working on a range of projects to increase biodiversity and improve agricultural processes. Nationally, the CSIRO is breeding new types of drought-tolerant wheat that will hopefully prevent a decline in productivity as the landscape becomes drier.

We’re already seeing the effects climate change is having on the natural world. Even if governments start making a serious effort to combat climate change today, we won’t be starting from zero – the clock started long ago, but we’re still crouched at the starting block.

Sooner or later, we’ll all be touched by climate change in some way, as indeed many already have. Hopefully we’ll be prepared for it.

Original story here

 

 

 

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