Author: Neville

New Models Predict Drastically Greener Arctic in Coming Decades

Mar. 31, 2013 — New research predicts that rising temperatures will lead to a massive “greening,” or increase in plant cover, in the Arctic. In a paper published on March 31 in Nature Climate Change, scientists reveal new models projecting that wooded areas in the Arctic could increase by as much as 50 percent over the next few decades. The researchers also show that this dramatic greening will accelerate climate warming at a rate greater than previously expected.

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“Such widespread redistribution of Arctic vegetation would have impacts that reverberate through the global ecosystem,” said Richard Pearson, lead author on the paper and a research scientist at the American Museum of Natural History’s Center for Biodiversity and Conservation.

Plant growth in Arctic ecosystems has increased over the past few decades, a trend that coincides with increases in temperatures, which are rising at about twice the global rate. The research team — which includes scientists from the Museum, AT&T Labs-Research, Woods Hole Research Center, Colgate University, Cornell University, and the University of York — used climate scenarios for the 2050s to explore how this trend is likely to continue in the future. The scientists developed models that statistically predict the types of plants that could grow under certain temperatures and precipitation. Although it comes with some uncertainty, this type of modeling is a robust way to study the Arctic because the harsh climate limits the range of plants that can grow, making this system simpler to model compared to other regions such as the tropics.

The models reveal the potential for massive redistribution of vegetation across the Arctic under future climate, with about half of all vegetation switching to a different class and a massive increase in tree cover. What might this look like? In Siberia, for instance, trees could grow hundreds of miles north of the present tree line.

“These impacts would extend far beyond the Arctic region,” Pearson said. “For example, some species of birds seasonally migrate from lower latitudes and rely on finding particular polar habitats, such as open space for ground-nesting.”

In addition, the researchers investigated the multiple climate change feedbacks that greening would produce. They found that a phenomenon called the albedo effect, based on the reflectivity of Earth’s surface, would have the greatest impact on the Arctic’s climate. When the sun hits snow, most of the radiation is reflected back to space. But when it hits an area that’s “dark,” or covered in trees or shrubs, more sunlight is absorbed in the area and temperature increases. This has a positive feedback to climate warming: the more vegetation there is, the more warming will occur.

“By incorporating observed relationships between plants and albedo, we show that vegetation distribution shifts will result in an overall positive feedback to climate that is likely to cause greater warming than has previously been predicted,” said co-author Scott Goetz, of the Woods Hole Research Center.

This work was funded by the National Science Foundation, grants IPY 0732948, IPY 0732954, and Expeditions 0832782. Other authors involved in this study include Steven Phillips (AT&T Labs-Research), Michael Loranty (Woods Hole Research Center and Colgate University), Pieter Beck (Woods Hole Research Center), Theodoros Damoulas (Cornell University), and Sarah Knight (American Museum of Natural History and University of York).

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Congestion in Earth’s Mantle: Mineralogists Explain Why Plate Tectonics Stagnates in Some Places

Mar. 31, 2013 — Earth is dynamic. What we perceive as solid ground beneath our feet, is in reality constantly changing. In the space of a year Africa and America are drifting apart at the back of the Middle Atlantic for some centimeters while the floor of the Pacific Ocean is subducted underneath the South American Continent. “In 100 million years’ time Africa will be pulled apart and North Australia will be at the equator,” says Prof. Dr. Falko Langenhorst from the Friedrich Schiller University Jena (Germany). Plate tectonics is leading to a permanent renewal of the ocean floors, the mineralogist explains. The gaps between the drifting slabs are being filled up by rising melt, solidifying to new oceanic crust. In other regions the slabs dive into the deep interior of Earth and mix with the surrounding Earth’s mantle.

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Earth is the only planet in our solar system, conducting such a ‘facelift’ on a regular basis. But the continuous up and down on Earth’s crust doesn’t run smoothly everywhere. “Seismic measurements show that in some mantle regions, where one slab is subducted underneath another one, the movement stagnates, as soon as the rocks have reached a certain depth,” says Prof. Langenhorst. The causes of the ‘congestion’ of the subducted plate are still unknown. In the current issue of Nature Geoscience, Prof. Langenhorst and earth scientists of Bayreuth University now explain the phenomenon for the first time.

According to this, the rocks of the submerging ocean plate pond at a depth of 440 to 650 kilometers — in the transition zone between the upper and the lower Earth mantle. “The reason for that can be found in the slow diffusion and transformation of mineral components,” mineralogist Langenhorst explains. On the basis of high pressure experiments the scientists were able to clarify things: under the given pressure and temperature in this depth, the exchange of elements between the main minerals of the subducted ocean plate — pyroxene and garnet — is slowed down to an extreme extent. “The diffusion of a pyroxene-component in garnet is so slow, that the submerging rocks don’t become denser and heavier, and therefore stagnate,” the Jena scientist says.

Interestingly there is congestion in Earth’s mantle exactly where the ocean floor submerges particularly fast into the interior of Earth. “In the Tonga rift off Japan for example, the speed of subduction is very high,” Prof. Langenhorst states. Thereby the submerging rocks of the oceanic plate stay relatively cold up to great depth, which makes the exchange of elements between the mineral components exceptionally difficult. “It takes about 100 Million years for pyroxene crystals which are only 1 mm in size to diffuse into the garnet. For this amount of time the submerging plate stagnates,” Langenhorst describes the rock congestion. It can probably only diffuse at the boundary of the lower Earth mantle. Because then pyroxene changes into the mineral akimotoite due to the higher pressure in the depth of 650 kilometers. “This could lead to an immediate rise in the rock density and would enable the submerging into greater depths.”

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Scientists say the data is clear that sea levels have risen significantly

Updated 1 April 2013, 17:04 AEST

For many islands nations and vast stretches of coastal communities in the Pacific, sea level rises are a reality that clouds their future.
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Scientists say the data is clear that sea levels have risen significantly (Credit: ABC)
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Heading the list of countries most endangered by global warning are Tuvalu, Kiribati and Marshall Islands.

Scientists are very clear about their predictions of significant sea levels rises in the future.

But what hard data do we have already to prove the trend.

Cathy Harper reports, leading agencies in the region, including Australia’s Bureau of Meteorology, the C-S-I-R-O and the University of Hawaii all say the data is clear that sea levels are rising.

Presenter: Cathy Harper

Speakers: Phil Thompson, Sea Level Centre, University of Hawaii; John Church, CSIRO fellow, Centre for Australian Weather and Climate Research; David Jones, manager of climate monitoring and prediction, Australian Bureau of Meteorology

HARPER: The Sea Level Center at the University of Hawaii does research on regional sea levels.

An expert at the Center, Phil Thompson, says there’s lots of good quality data available on sea levels.

THOMPSON: The Sea Level Center here in Hawaii we operate tide gauges, but that’s only one of the measurements that we use to study sea level There are also satellite altimeters which are satellites that fly around the world and they measure height within about a few centimetres over most of the ocean. Which give us a really complete picture of how sea levels are changing almost everywhere on Earth. The primary limitation of the satellite data though is that those actually weren’t actually launched until the early 1990s so the question becomes what we’re observing with the satellites now, how does that fit into the longer term context like during the twentieth century and that’s where we use the tide gauges.

HARPER: What does the data that we have tell us about what sea levels in the tropical Pacific actually doing?

THOMPSON: Well, sea levels in the Western Tropical Pacific have actually been going up very fast in recent decades and we know this very well from what I was talking about with the satellite measurements of sea level. So global sea level over the past two decades or so rose about six centimetres, about. However in the western tropical Pacific with Guam and those areas in the Philippines sea levels actually increased about 30 centimetres during that same two decades which is roughly five times as much as the global rate. In contrast to that however, sea levels in the eastern Pacific have actually changed very little over the same time period. So it’s actually an important question as to why sea levels would be changing, rising so rapidly in the West and not really rising in the east. And the simple answer to that is because of the wind. The trade winds that blow from east to west over the tropical Pacific have actually been increasing in strength over the past couple of decades. And that’s led to sea levels rising faster in the west and slower in the east. And actually if we look at tide gauges of sea levels in those areas in earlier decades, such as the 50s, 60s and 70s that situation was actually reversed and sea levels were rising faster in the east and slower in the west.

HARPER: These fluctuations have also been observed by John Church – a CSIRO fellow at the Centre for Australian Weather and Climate Research, which is a partnership between the CSIRO and Australia’s Bureau of Meteorology.

CHURCH: We believe these are natural phenomena so they’ve happened before, and they’re superimposed on the climate change signal. Now there is a question which you could ask … Is some of this pattern actually related to a pattern of climate change such that climate change is resulting in an increased strength of the south east trades and the trade winds in the equatorial Pacific and I think the answer to that is really not known.

HARPER: There’s no doubt in John Church’s mind, however, that sea levels globally, and in the Pacific, have been rising steadily over the past century.

The Australian Bureau of Meteorology – another leading Australian agency in terms of sea levels – says the data on what sea levels have done in the past is clear.

Dr David Jones is the manager of climate monitoring and prediction at the Bureau.

JONES: Things like sea level are remarkably easy to cross check to compare against other variables, such as temperature, to compare against what’s happening with the ice sheets. And scientists are doing this all the time. I guess there’s a couple of safeguards here for science. One is that people look for consistency. So you don’t just pick out one tide gauge and say, well is this the global trend. We look at hundreds or thousands of data and draw a general conclusion. The other one is really that we’re always looking at our own results and ways of looking at other people’s results. So there is continuous cross checking. If things don’t look right your peers will usually tell you and tell you in no uncertain terms. So you know, look, the results are very robust and absolutely no alternative conclusion other than that sea levels are rising.

HARPER: There are a lot of warnings around for countries in the Pacific especially to prepare for rising sea levels. Is that necessary if we’re really not sure exactly what sea levels are going to do in the future? For example, if the rises in the western Pacific that we’ve seen over the past few decades then reverse in the next few decades?

JONES: Well, we will see variability, so every single year, the sea level won’t be higher. But in the long term the trends are fairly obvious. We’re expecting something around about 50 centimetres of further sea level rise this century. Now we might get lucky and it might be more like 20 or 30 centimetres. Or we might get unlucky and it may end up around a metre. But the story is very clear. You know, people have to prepare for a rise in sea level, higher sea levels on average in the future, more erosion, more coastal inundation, so there really is a clear need for people to prepare and adapt.

Taiwan, Germany seek methane hydrate—potentially vast new energy source March 31, 2013 Enlarge Attendant of Japan’s Gas Pavilion introduces an experiment of the “burning ice,” methane hydrate, as a potential future source of energy in Nagakute, Aichi prefecture, on March 19, 2005. A research vessel carrying German and Taiwanese scientists set sail for waters off the island’s southwestern coast on Sunday in search of this potentially vast new energy source. A research vessel carrying German and Taiwanese scientists set sail for waters off the island’s southwestern coast on Sunday in search of methane hydrate, a potentially vast new energy source. google_protectAndRun(“render_ads.js::google_render_ad”, google_handleError, google_render_ad);Ads by GoogleCompare Energy Prices – Paying too much on energy bills? Find a plan that suits your needs – www.CompareTheMarket.com.au/Energy The substance, a fossil fuel that consists of very densely-packed methane trapped in ice, is found beneath the seafloor on continental shelves and in the Arctic’s permafrost. Earlier this month, Japan announced it had successfully extracted the hydrate, known as “fire ice”, from its seabed, a move it called a world first and a major breakthrough for the energy-starved nation. The 4700-tonne German ship, called the “Sonne” will undertake a 50-day expedition at a cost of around $3.98 million, three-quarters of which will be funded by Germany and the remainder by Taiwan. “This will be the first time we may be able to physically explore for the substance,” Wayne Wang of Taiwan’s National Science Council told AFP. Past studies have indicated reserves in the area could supply the island for up to 50 years. Nuclear energy currently accounts for around 20 percent of the island’s energy mix but has become increasingly controversial in recent years following Japan’s atomic crisis. Taiwan is heavily dependent on costly oil imports mainly from the Middle East and Africa. (c) 2013 AFP

Read more at: http://phys.org/news/2013-03-taiwan-germany-methane-hydratepotentially-vast.html#jCp

Bit by bit, Gillard fails to deliver on her promises

Date April 1, 2013 Category Opinion 69 reading now

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Amanda Vanstone

Former Howard government minister

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We’re all paying for Labor’s childish spending choices.

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Prime Minister Julia Gillard. Photo: Andrew Meares

My husband is one of those crazy guys who really, really likes cars. On holidays overseas he experiences genuine pleasure seeing hordes of flash cars that we might see only rarely in Australia.

His current desire is to own some sort of turbocharged Bentley that looks a bit like a Batman car to me. Alternatively, a Rolls-Royce. In my less-caring moments I take a cue from The Castle and tell him he’s dreaming.

Lately my position seems a little selfish and uncharitable. So, just this once, I will take a leaf out of Julia Gillard’s songbook. My husband Tony will be ecstatic when I announce with an air of determined generosity that he can have the car of his dreams and there will be no argument. He will be incredulous when he hears that the car will be a gift from me. And when I hand over a little parcel with a key ring and some keys, he will be champing at the bit to find where I have placed the vehicle so he can jump in for a quick spin.

That’s where there might be a bit of trouble. I will have to explain that he is getting the car in bits, piece by piece, because I obviously do not have that kind of money sitting around doing nothing. It is hard to imagine he will be enthused by the promise of some tyres next month, the engine next year and the body somewhere further down the track. He will feel cheated. He will be annoyed at what he will see as a stupid joke.

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But this is what our Prime Minister does to us regularly. She, like all of us, would like to see a much better deal for people affected by disability. So she announces she will deliver it. She paints herself as the hero of the disability sector. Except she doesn’t have the money. What makes it worse is she knows it.

It is a bitter pill for people who really do need some good news. Similarly, Gillard will seek to paint herself as the hero of education. Again, realistically, she just cannot deliver. She has neither the money nor the likelihood of having the power.

I think the electorate will be very unforgiving of a Prime Minister who appears to think she can fool most of the people most of the time.

As the budget approaches, voters will no doubt recall the promises last year of, finally, producing a surplus.

Various financial houses are predicting a deficit of $10 billion, $15 billion or even $20 billion.

It’s a confusing message from an apparently confused government. We are told the economy is in great shape. That leaves many voters wondering why we can’t balance the books. Every voter and every family understands that every now and then money has to be borrowed. What they don’t understand is why this government keeps borrowing and borrowing and spending and spending.

From Treasurer Wayne Swan there will be the same tired excuses. He might suggest commodity prices have fallen and appear oblivious to the fact everyone else has understood from day one the reality of commodity price fluctuations. It is as if the Treasurer expects us to believe that price fluctuations, unexpected natural disasters and all the other variables that might affect the budget are somehow new-found difficulties that he is managing masterfully. If only that were true. Every government has to handle these variables.

My granny didn’t have much of a formal education but, like many people, she learnt from life. She knew you had to live within your means and that wise people put something away for a rainy day.

She understood that the best time to fix your roof is while the sun is shining and she knew that while it was fair enough to borrow money, in the end you could not keep spending more than you earned.

Oh that Wayne Swan had lived her life and learnt those lessons.

He seems to think, like a kid in a lolly shop, that all his problems are the fault of those who are simply not giving him enough money.

As kids grow up they come to grips with having to make choices that fit their budget.

The Treasurer’s problem is the government’s clear inability to make spending choices that fit our budget. It either takes more from voters, perhaps by raiding superannuation, or it borrows from the next generation. Fortunately, the voters, according to the pollsters, have probably wised up to Gillard and her coterie of ministers who promise everything, mess up the implementation and borrow the money from our kids.

You might ask why Gillard and her ministers seem to care not one jot about the mess they have created. The answer is simple. They are beholden to a few old-time bully-boy unions. That’s where they get their power within the Labor movement.

Our political leaders kowtow not to us but to a movement riddled with corruption, bullying and a fair dose of misogyny. That’s why we are seeing the reinvention of the old divide-and-rule tactics. A quick dose of class warfare and the politics of envy makes them feel powerful. It is standard old-time union stuff. ”We will take from the rich and give to the poor” makes them feel like Robin Hood.

Smart unionists and decent Labor people realised long ago how outdated, counterproductive and stupid this sort of thinking is. They must look at Labor today and weep.

Amanda Vanstone is a columnist for The Age and was a minister in the Howard government.

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Earth-cooling schemes need global sign-off, researchers say

World’s most vulnerable people need protection from huge and unintended impacts of radical geoengineering projects
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Ian Sample, science correspondent

The Guardian, Sunday 31 March 2013 17.59 BST

Grimsvotn volcano erupts in Iceland in 2011. Solar radiation management schemes spray particles into the atmosphere to simulate cooling effects of volcanic eruptions. Photograph: Egill Adalsteinsson/EPA

Controversial geoengineering projects that may be used to cool the planet must be approved by world governments to reduce the danger of catastrophic accidents, British scientists said.

Met Office researchers have called for global oversight of the radical schemes after studies showed they could have huge and unintended impacts on some of the world’s most vulnerable people.

The dangers arose in projects that cooled the planet unevenly. In some cases these caused devastating droughts across Africa; in others they increased rainfall in the region but left huge areas of Brazil parched.

“The massive complexities associated with geoengineering, and the potential for winners and losers, means that some form of global governance is essential,” said Jim Haywood at the Met Office’s Hadley Centre in Exeter.

The warning builds on work by scientists and engineers to agree a regulatory framework that would ban full-scale geoengineering projects, at least temporarily, but allow smaller research projects to go ahead.

Geoengineering comes in many flavours, but among the more plausible are “solar radiation management” (SRM) schemes that would spray huge amounts of sun-reflecting particles high into the atmosphere to simulate the cooling effects of volcanic eruptions.

Volcanoes can blast millions of tonnes of sulphate particles into the stratosphere, where they stay aloft for years and cool the planet by reflecting some of the sun’s energy back out to space.

In 2009, a Royal Society report warned that geoengineering was not an alternative to cutting greenhouse gas emissions, but conceded the technology might be needed in the event of a climate emergency.

Writing in the journal Nature Climate Change, Haywood and others show that moves to cool the climate by spraying sulphate particles into the atmosphere could go spectacularly wrong. They began by looking at the unexpected impacts of volcanic eruptions.

In 1912 and 1982, eruptions first at Katmai in Alaska and then at El Chichón in Mexico blasted millions of tonnes of sulphate into northern skies. These eruptions preceded major droughts in the Sahel region of Africa. When the scientists recreated the eruptions in climate models, rainfall across the Sahel all but stopped as moisture-carrying air currents were pushed south.

Having established a link between volcanic eruptions in the northern hemisphere and droughts in Africa, the scientists returned to their climate models to simulate SRM projects.

The scientists took a typical project that would inject 5m tonnes of sulphate into the stratosphere every year from 2020 to 2070. That amount of sulphate injected into the northern hemisphere caused severe droughts in Niger, Mali, Burkina Faso, Senegal, Chad and Sudan, and an almost total loss of vegetation.

The same project had radically different consequences if run from the southern hemisphere. Rather than drying the Sahel, cooling the southern hemisphere brought rains to the Sahel and re-greened the region. But Africa’s benefit came at the cost of slashing rainfall in north-eastern Brazil.

The unintended consequences of SRM projects would probably be felt much farther afield. “We have only scratched the surface in looking at the Sahel. If hurricane frequencies changed, that could have an impact on the US,” said Haywood.

Matthew Watson, who leads the Spice project at Bristol University, said the study revealed the “dramatic consequences” of uninformed geoengineering.

“This paper tells us there are consequences for our actions whatever we do. There is no get-out-of-jail-free card,” he told the Guardian.

“Whatever we do is a compromise, and that compromise means there will be winners and losers. That opens massive ethical questions: who gets to decide how we even determine what is a good outcome for different people?

“How do you get a consensus with seven billion-plus stakeholders? If there was a decision to do geoengineering tomorrow, it would be done by white western men, and that isn’t good,” Watson said.