Alaska’s glaciers melt faster as climate change speeds up

Alaska's glaciers melt faster as climate change speeds up

Climate change rather than natural causes is the main cause of Alaska’s glacier loss, which is set to speed up, US scientists say.

LONDON, 30 June, 2015 – The glaciers of Alaska are melting and retreating: the chief cause is climate change and the loss of ice is unlikely to slow, according to a new study by US scientists.

They calculate that the frozen rivers of the Pacific coast of America’s northernmost state are melting fast enough to cover the whole of Alaska with 30 cms of water every seven years.

Since Alaska is enormous – it covers 1.5 million square kilometres and is the size of California, Texas and Montana put together – this adds up to a significant contribution to sea level rise.

“The Alaska region has long been considered a primary player in the global sea level budget, but the exact details of the drivers and mechanisms of Alaska glacier change have been stubbornly elusive,” said Chris Larsen, a geophysicist at the University of Alaska Fairbanks, and lead author of a study in Geophysical Research Letters.

Taxonomy of change

Scientists from the University of Alaska and the US Geological Survey analysed studies of 116 glaciers in the Alaska region over a 19-year-period to estimate the rate at which ice melted and icebergs calved.

They used airborne lidar remote sensing technology and other techniques, historical data and a global glacier inventory to establish a kind of taxonomy of glacier change.

The Columbia Glacier in Prince William Sound had retreated more than 19 kilometres because of iceberg calving and had thinned by 450 meters in height since 1980. But, unexpectedly, tidewater glaciers – those that end in the ocean – seemed to make comparatively little contribution to sea level rise.

“Instead we show that glaciers ending on land are losing mass exceptionally fast, overshadowing mass changes due to iceberg calving, and making climate-related melting the primary control on mountain glacier mass loss,” Dr Larsen said.

Big contributor

He and his colleagues calculated that Alaska is losing ice at the rate of 75 billion metric tons a year. Such research is just one more piece of careful cross-checking in the great mosaic of climate research: another systematic confirmation that overall, glaciers are not losing ice in response to some natural cycle of change of the kind that occasionally confuses the picture for climate science.

The agency at work is largely global warming as a response to the steady rise in atmospheric carbon dioxide as a consequence of the burning of fossil fuels.

Mountain glaciers represent only 1% of the total ice on the planet: the other 99% is found in Greenland – which is melting fast – and in the great frozen continent of Antarctica, where ice mass is being lost at an increasing rate.

But although the mountains of the temperate and tropic zones bear only a tiny percentage of the planet’s ice, their melting accounts for almost a third of the sea level rise currently measured by oceanographers, and this melting will go on to become a big contributor to the sea levels later this century.

“Alaska will continue to be a major driver of sea level change in the upcoming decades”

Across the border in Canada, glaciologists have warned that the country will lose a huge volume of flowing ice, and while one team has confirmed that air pollution rather than global warming long ago began to strip Europe’s Alps of their glaciers, in general mountain peaks are warming faster than the valleys and plains below them.

Geophysicists and glaciologists have established that the glaciers of the tropical Andes are at risk, and in the Himalayan mountain chain glaciers seem to be in inexorable retreat with consequences that could be devastating for the many millions in the Indian subcontinent and in China who rely on seasonal meltwater for agriculture.

Glaciers are by definition hard to study – they are high, cold and in dangerous terrain – and such research is inevitably incomplete: the scientists for instance excluded glaciers smaller than three square kilometres. But together these small patches of flowing ice account for 16% of Alaska’s glaciated landscape. The 116 glaciers in the survey together added up to only 41% of the state’s glaciated area.

But the pattern established by the Fairbanks team suggests that melting will accelerate with climate change. “Rates of loss from Alaska are unlikely to decline, since surface melt is the predominant driver, and summer temperatures are expected to increase,” said Dr Larsen.

“There is a lot of momentum in the system, and Alaska will continue to be a major driver of sea level change in the upcoming decades.” – Climate News Network

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Scientists detect mysterious warming in US coastal waters

Scientists detect mysterious warming in US coastal waters

Unprecedented ocean temperature rises off the Atlantic and Pacific coasts of the US may be linked to sea level rise or the recent pattern of “weird” weather.

LONDON, 28 June, 2015 − Oceanographers are puzzled by an accelerated burst of warming sea that threatens the fisheries of the American Atlantic coast.

Meanwhile, off the US West coast, scientists report that they have been baffled by a mysterious “blob” of water up to 4°C warmer than the surrounding Pacific, linked to weird weather across the entire country.

Jacob Forsyth and research colleagues from the Woods Hole Oceanographic Institution (WHOI) in Massachusetts report in the Journal of Geophysical Research: Oceans that the ocean off the US north-east continental shelf has been warming at unprecedented levels for 13 years.

Their findings came after analysis of data from sensors − called bathythermographs − dropped 14 times a year from the container ship Oleander, which for 37 years has travelled between New Jersey and Bermuda. Each detector takes the temperature of the water column as it sinks up to 700 metres.

Startling discovery

What they were startled to discover was an unexplained, and unprecedented, rise in the water temperatures that may be linked with an equally mysterious sea level anomaly: sea levels are going up, but they are going up faster off the north-east coast of the US than almost anywhere else.

“The warming rate since 2002 is 15 times faster than from the previous 100 years,” says Glen Gawarkiewicz, a WHOI senior scientist and one of the authors of the report.

“There’s just been this incredible acceleration to the warming, and we don’t know if it’s decadal variability or if this trend will continue.”

“It’s producing conditions that we think are going to be more common with global warming”

To make sure of their perspective, the authors compared their analysis with surface data from the Nantucket lightship and other such installations along the coast, from 1880 to 2004. The new study shows that the warming is not just confined to surface waters.

Although there must be some link with the steady rise in atmospheric temperatures because of global warming as a result of human-made carbon dioxide emissions, the oceanographers suspect there may also be another explanation, so far undiscovered.

Off the Pacific coast, meteorologists have been scratching their heads over the appearance in 2014 of a “remarkably” warm patch −  1,500 kilometres across in every direction and 100 metres deep − that could be linked to “weird” weather across the continental US that has seen heat and drought in the west and blizzards and chills in the East.

High pressure ridge

Nicholas Bond,  a research meteorologist at the University of Washington in Seattle, and colleagues report in Geophysical Research Letters that what they have called “the blob” was linked to a persistent high pressure ridge, linked in turn to a calmer ocean during the last two northern hemisphere winters.

The blob plays a sure role in the West Coast weather. Air sweeping across it picks up heat, and this results in warmer temperatures and lower snowpack in coastal mountains − which certainly stoke up the conditions for drought.

A second study in Geophysical Research Letters links the warm Pacific puzzle to the big freeze in the eastern states in 2013 and 2014.

Once again, there doesn’t seem to be a direct connection with climate change, but it raises the spectre of changes to come.

“This is a taste of what the ocean will be like in future decades,” Dr Bond says. “It wasn’t caused by global warming, but it’s producing conditions that we think are going to be more common with global warming.” − Climate News Network

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New flood alert as warming raises sea levels threat

New flood alert as warming raises sea levels threat

Scientists warn countries in northern Europe to plan for dramatic new worst-case scenarios as climate change increases the risk of seas sweeping inland.

LONDON, 22 June, 2015 − Europe could face a higher marine invasion than anybody anticipated. As polar ice melts, tides could be as much as 1.5 metres higher around the coasts of Scandinavia, Germany, the Netherlands and England, according to a new study.

This is considerably higher than the average sea level rise – driven by global warming as a consequence of burning fossil fuels – projected by the Intergovernmental Panel on Climate Change under a “business as usual” scenario and a global average temperature rise of 4°C.

But there is no contradiction. The discrepancy arises because the seas have never been level, and the land keeps moving too.

Aslak Grinsted, associate professor in the Centre for Ice and Climate at the Niels Bohr Institute of the University of Copenhagen, Denmark, and colleagues report in the journal Climate Research that they took a closer look at the dynamics of sea level change in the North Sea, the North Atlantic and the Baltic for the remainder of this century.

Land uplift

“Even though the oceans are rising, they do not rise evenly across the globe,” Dr Grinsted says. “This is partly due to changes in the gravitational field and land uplift.”

He and his colleagues started with the anomalies they knew best. These are in Greenland, which is covered by a sheet of ice so massive that it gathers up the sea around it. So, to reach Greenland, ships must sail uphill.

As the ice sheet melts – and there are studies that show it is melting at an accelerating rate that would heighten sea levels by 14 cms this century – the mass will be reduced and the sea levels will fall, even though more water has entered the oceans.

“In England . . . we cannot exclude a sea level rise of up to 1.75 metres this century”

But although waters are notionally lapping ever higher along coastlines, these too are changing. Northern Europe 12,000 years ago was covered by deep ice, and the bedrock below was depressed. Now the ice has gone, but the land once crushed by it is still rising.

Equipped with the latest research and measurements, the Copenhagen team began their reinterpretation of the local future. They found that what had once been considered “high” scenarios for the Netherlands and England will be surpassed.

Best estimate

Dr Grinsted says: “For London, the calculated best estimate is that sea level will rise by 0.8 metres. In England, a sea level rise of more than 0.9 meters in this century has been considered highly unlikely, but our new calculation shows that there is a 27% chance that this limit is surpassed, and we cannot exclude a sea level rise of up to 1.75 metres this century.”

For the Netherlands, the best estimate of sea level rise is 0.83 metres, but the calculations show that there is a 26% chance that it will exceed the existing high-end scenario of 1.05 metres, and could even reach 1.80 metres.

Dr Grinsted says: “Both countries have already established protections for the coasts with barriers, sluice gates and dikes, but is it enough? I hope that our calculations for worst-case scenarios will be taken into consideration as the countries prepare for climate change.”

The IPCC sea level projection is of 80 cms worldwide. Sea levels overall might change little in Scotland, Ireland and Norway. And in the Gulf of Bothnia, in Finland, where the land is rising even faster than the sea, tides could be as much as 10cms lower at the end of the century. − Climate News Network

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Delegates accused of ‘fiddling’ while the planet burns

Delegates accused of ‘fiddling’ while the planet burns

Tame end to Bonn climate talks leaves critics fearing that hopes are fading of a binding agreement being signed to keep global warming in check.

LONDON, June 11, 2015 − For a meeting on which the future of the planet depends, there were remarkably few headlines coming out of the UN climate change conference in Bonn as it ended yesterday.

Critics believe that progress, after nearly two weeks of talks, was so slow that the chances of world leaders signing up to an agreement on tackling climate change in Paris later this year are receding − and that there is a lack of political will to do so.

Delegates agreed that a “streamlined” text of a legal agreement based on the negotiations so far should be drawn up and sent to governments to review.

This will cover issues such as how the agreement can be financed, who will cut greenhouse gas emissions, how to adapt to climate change, and compensation for nations badly affected. The negotiators will then come back to Bonn and try again.

Optimists will argue that this is progress, and that the talks were not supposed to be final, but merely moving towards a legally-binding agreement that will be signed by heads of state at the UN Framework Convention on Climate Change in Paris in December.

Sleepwalking

However, for many environment groups lobbying the talks, it was certainly not enough. The phrase “sleepwalking into Paris” was how Christian Aid  described it.

Their senior climate change adviser, Mohamed Adow, was quoted by the BBC as saying: “There has been too much time spent fiddling around with the unimportant details of the text. Negotiators have acted like schoolchildren colouring in their homework timetable and not getting round to any actual homework.”

It was not all bad news. One of the surprising breakthroughs was an agreement that will enable poorer countries to receive money for keeping their forests standing.

Trying to preserve the world’s forests in order to store carbon, and so protect the climate, has been a thorny issue since the first Earth Summit in Rio in 1992.

“Negotiators have acted like schoolchildren colouring in their homework timetable and not getting round to any actual homework”

The scheme for Reducing Emissions from Deforestation and Forest Degradation, known as UN-REDD, was originally going to be a Forest Convention, but developing countries rejected that on the grounds that it was up to them how they used their own natural resources. In any case, they said, the developed world had already cut down its forests.

After 20 years of talking, the increasing recognition that forests are more valuable in their pristine state than logged or clear-cut, and that rich countries were prepared to compensate poorer ones for not cutting them down, finally led to agreement.

Brazil, still battling to reduce Amazon deforestation, was among the countries pushing for an early settlement.

Package of deals

Although the agreement has been reached, it cannot come into operation until the end of the Paris conference, when it is supposed to be part of the package of deals that will save the climate from going over the internationally-agreed 2˚C temperature rise limit above pre-industrial levels.

The main sticking point in the past, at the Bonn talks, and for the future is the small matter of $100 billion pledged in aid by the rich countries to developing nations by 2020 to help them to adapt to climate change and still develop at the same time.

Money has been trickling in to various funds set up for the purpose, but there is no sign that the bulk of the donations will actually materialise.

Another serious problem is that the pledges that larger countries have made to reduce emissions are not enough to stop the world overheating beyond the 2˚C limit agreed by politicians.

So far, more than 30 countries have pledged to limit emissions of greenhouse gases, with around 150 smaller countries yet to set goals.

A bright spot on the pledges front was the agreement of the G7 group of countries to phase out all electricity production from fossil fuels by the end of this century.

However, as critics pointed out, what the leaders failed to do was outline any measures they were prepared to take now to set the world on the right course.

Another vexed issue yet to be resolved is compensation for the loss and damage suffered by poorer countries because of sea level rise and storms for which they are not responsible.

Impatient with progress at the talks, some of the poorer nations − Vanuatu, Kiribati, Tuvalu, Fiji, the Solomon Islands, and the Philippines − announced that they would be taking a human rights case again big oil, coal and gas companies, and demanding compensation.

There are signs that public opinion − so often in the past indifferent to the issue of climate change − is now taking the issue more seriously.

A vast poll that involved testing public opinion in 70 countries on the same day found that 80% of people are very concerned about climate change, and 67% back a legally-binding agreement for all countries to reduce emissions.

Avoided showdown

Jan Kowalzig, Oxfam climate change policy adviser, summed up the feelings of environmental observers in Bonn when he said: “Negotiators avoided a showdown over crunch issues such as finance and increasing near-term emissions cuts, but they are only delaying the inevitable.

“A clearer mandate from heads of state and ministers is needed to ignite the talks and ensure key questions are answered.

“Political leaders need to give a clear steer on how to address the inadequacy of current emissions reductions pledges, but also on the urgent financial support needed for the most vulnerable countries and populations.”

Once governments have had a chance to review the “streamlined texts”, delegates will return to Bonn in August and October for more rounds of talks, before the Paris summit at the end of the year. – Climate News Network

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India’s coastal villages map out disasters strategy

India’s coastal villages map out disasters strategy

The Indian Ocean can be an angry and sometimes lethal neighbour, but those who live beside it are now learning how to prepare for its next onslaught.

CHENNAI, 26 May, 2015 – It has been over a decade since the devastating tsunami struck southeast Asia, but the horrific memories remain as vivid as ever for people in the coastal villages of the south Indian state of Tamil Nadu.

Now, in the aftermath of the 2004 tsunami and also two cyclones, local people are benefiting from the Indian government’s encouragement of international co-operation in helping vulnerable communities, and have produced a hazard map as a precaution against future disasters.

Vikas Shankar, from the fishing village of Sulerikattukuppam, remembers clearly the moment the tsunami struck.“I was engrossed in playing cricket when I saw water entering the village,” he says. “I thought it was just another day when the sea poured in. Then, suddenly, I saw my mother caught in a whirlpool and realised something was seriously wrong.”

His mother, Tilakavathy, survived the tsunami’s fury, but recalls: “I thought this was really the end of the world.”

Completely destroyed

Amazingly, no one in the village died, but fishermen lost their gear and livelihoods, and many buildings close to the shore were completely destroyed.

The tsunami prompted Tilakavathy and her husband to decide not to send their sons to sea to earn a livelihood.

When Vikas, their youngest son, was old enough, he was sent instead to the local community college, built in 2011 by the state government to provide education and alternative livelihood opportunities for the fishing community.

The local people, recognising the need for disaster preparedness, are now involved in a programme that focuses on  developing communication tools for vulnerable communities and raising awareness of other disaster-related issues.

Krishnamurthy Ramasamy, professor of applied geology at the University of Madras, was formerly the principal of the community college. He says: “We realised the need for international collaboration to build a curriculum on disaster management and field-based learning activities.”

Kyoto University in Japan was one of the universities keen to work with him, and two Australian universities, Melbourne and Victoria, also joined in, helping with funds, curriculum development and exchange visits.

“We were taught how and why cyclones and tsunamis happen. It helped us to understand disasters in the first place.”

The college itself fostered community-based preparedness by offering disaster management as an optional subject, and by helping to set up a Local Residents’ Alliance (LRA) in 2013 to mobilise villagers. Most members of this group were parents of students from the college.

Vikas Shankar says: “In the class, we were taught how and why cyclones and tsunamis happen. It helped us to understand disasters in the first place.”

To learn about other people’s best practices, Professor Ramasamy visited communities along the Japanese coast, and there he made a significant discovery. He says: “The first thing I noticed in each village was the hazard map. I thought that we needed this too.”

Back at the college, work on hazard map preparation began, and the first step was students surveying their own villages to understand the geography better.

Teams went from house to house and marked all the huts in the village. They counted the number of people in the house, with details of numbers of women, children, old and disabled people living there. All this information went on the hazard map.

Miwa Abe, from the Centre for Policy Studies at Kumamoto University, Japan, who trained the Indian students, says: “A hazard mapping exercise with local people gives them an opportunity to know their village.

“It is not only about environmental conditions, but also human relationships, social networks, architectural conditions. Usually people do not think about their own area because it is too familiar to them.”

Evacuation routes

The teams also prepared evacuation routes, and, after six months of rigorous work, the students presented the final map to the local people.

Today, as one walks into the village, the first thing to catch the eye is the big blue hazard map board at its entrance. It shows the evacuation routes to be followed during disasters, and also the village’s population distribution − crucial information so that local people will know who to rescue first, and where they live.

The village’s approach is now being used as a case study in efforts to prepare community-based disaster management (CBDM) plans for the entire district, and eventually as a model for the state. The Tamil Nadu government has given land adjacent to the college to establish permanent infrastructure and to provide better facilities for the students.

Rajalakshmi Mahadevan, a fisherman’s daughter, says: “The evacuation map can be read by anyone, even a newcomer. Now we know which house to go to, who to evacuate first, and this has lifted the fear of disaster from local people’s minds.”– Climate News Network

  • Sharada Balasubramanian, an independent journalist from Tamil Nadu, India, writes on energy, agriculture and the environment. Email: sharadawrites@gmail.com; Twitter: @sharadawrites

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Antarctic ice is under attack from sea and air

Antarctic ice is under attack from sea and air

Satellite and radar studies show that twin forces causing the vast ice shelf to thin and become less stable could have a serious impact on global sea levels.

LONDON, 18 May, 2015 − Scientists have measured the rate of thinning of the great sea ice shelf of the Antarctic Peninsula and have identified the mechanisms at work above and below the shelf.

The collapse of floating sea ice makes no direct difference to global sea levels – but the effects could nevertheless lead to higher waters everywhere.

Paul Holland, of the British Antarctic Survey (BAS), and research colleagues from the US report in the journal The Cryosphere that they used satellite measurements and radar studies between 1998 and 2012 to confirm that the Larsen C ice shelf has lost four metres of ice, and is a metre lower at the surface.

Warmer waters

This is the largest of three shelves that have been under study for decades; the Larsen A and Larsen B shelves have already broken off and drifted north to warmer waters.

The Antarctic Peninsula is one of the fastest-warming regions of the world: 2.5°C in the last 50 years.

“What’s exciting about this study is we now know that two different processes are causing Larsen C to thin and become less stable,” says Dr Paul Holland, lead author of the BAS study.

“Air is being lost from the top layer of snow (called the firn), which is becoming more compacted, probably because of increased melting by a warmer atmosphere.

“We expect that sea-level rise around the world will be something in excess of 50 cm higher by 2100 than it is at present”

“We know also that Larsen C is losing ice, probably from warmer ocean currents or changing ice flow. If this vast ice shelf − which is over two and a half times the size of Wales, and 10 times bigger than Larsen B − was to collapse, it would allow the tributary glaciers behind it to flow faster into the sea. This would then contribute to sea-level rise.”

A collapse of the shelf could occur within a century. When the two companion Larsen glaciers broke away, the glaciers that flowed from the ice-capped continent towards the sea began to accelerate.

Offshore ice, held fast to the shoreline, is a factor that helps keep glacier flow at its proverbially glacial pace. Once it has gone, the frozen rivers of ice onshore naturally begin to flow faster.

“We expect that sea-level rise around the world will be something in excess of 50 cm higher by 2100 than it is at present, and that will cause problems for coastal and low-lying cities,” says David Vaughan, director of science at the BAS.

“Understanding and counting up these small contributions from Larsen C and all the glaciers around the world is very important if we are to project, with confidence, the rate of sea-level rise into the future.”

The study is a confirmation of earlier research in which other groups, using different approaches, have already identified shelf ice loss and have warned that Antarctic melting could accelerate. Satellite-based measurements have also linked glacial melting with an acceleration in sea level rise.

Precision measurement of sea level rise is not easy. Oceans rise and fall with the tides, the water isn’t level anyway, and salinity and temperature differences in the oceans, and gravitational anomalies in the ocean basins, all mean that the ocean surfaces naturally undulate.

And the continents don’t keep still. Land surfaces from which researchers base their measurements also slowly rise or fall.

Accelerated rise

Christopher Watson, senior lecturer in the School of Land and Earth at the University of Tasmania, Australia, and colleagues report in Nature Climate Change that a different approach to the problem suggests that – contrary to previous estimates – sea level rise has accelerated in the last decade.

He and his colleagues searched not just global positioning satellite evidence from the surface waters but also from the land for signs of “bias” in the data. They also used evidence from hourly tide gauges from around the world and recalculated the rate of change.

What they found was that, overall, sea level rise in the last two decades has been at a rate just under, rather than just over, 3mm a year.

But the overestimate for the first six years of the survey had been much higher, which in turn suggested that the rate of rise had actually accelerated during this century, in a way that is consistent with the rate of glacial melting − at least from the Greenland and West Antarctic ice caps. – Climate News Network

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Scientists weigh up new evidence on Antarctic ice melt

Scientists weigh up new evidence on Antarctic ice melt

Southern continent’s mysteries start to unfold as satellite data is used to measure the extent and pattern of increased ice loss that threatens to be a “runaway problem”.

LONDON, 7 May, 2015 − Antarctica has been losing its ice cover at an average rate of 92 billion tons a year since at least 2003, according to new research.

And while the scientists can’t yet say for certain that human-made climate change is the main cause, they warn that the ice loss has the potential to have serious impacts on sea level rise.

The southern continent is the Earth’s largest store of fresh water, but is also its least studied area, having had no known human visitors until the late 18th century. So while scientists have a clear idea of processes at work in the Arctic, the big picture at the other end of the planet has been uncertain.

Heavier snowfalls

West Antarctica has been losing vast chunks of ice, but greater average warmth has meant there have been heavier snowfalls, and the icepack in east Antarctica has been on the increase.

Now Christopher Harig and Frederik Simons, geoscientists at Princeton University in the US, report in the journal Earth and Planetary Science Letters that gravitational satellite data has delivered a method of “weighing” the ice sheet, and identifying a pattern of change.

Most of the loss has been from the West Antarctic region, where the glaciers are increasingly unstable. In 2008, the region was shedding ice at the rate of 121 billion tons a year. By 2014, this rate of loss had doubled.

At the same time, the ice sheet in East Antarctica had thickened – but  the gain made up for only about half the ice lost from the west.

Most scientists would be hard-pressed to find mechanisms that do not include human-made climate change”

In the period since 2003, ice loss over the whole continent increased at the rate of six billion tons a year. West Antarctica’s melting rate, however, accelerated by 18 billion tons a year during the same timespan.

So the researchers did the sums and arrived at an annual average loss of 92 billion tons a year. This could be envisaged as an iceberg the size of Manhattan Island in New York, and more than 1,600 metres high.

What the researchers cannot be sure of is the cause: is a natural cycle of climate at play, or is it a consequence of global warming because  of greenhouse gas emissions from the burning of fossil fuels?

“We have a solution that is very solid, very detailed and unambiguous,” Dr Simons says. “A decade of gravity analysis alone cannot force you to take a position on this ice loss being due to anthropogenic global warming. All we have done is take the balance of the ice on Antarctica and found that it is melting – there is no doubt.

Rapidly accelerating

“But with the rapidly accelerating rates at which the ice is melting, and in the light of other, well-publicised lines of evidence, most scientists would be hard-pressed to find mechanisms that do not include human-made climate change.”

The two scientists used data from a US-German research satellite called GRACE − short for Gravity Recovery and Climate Experiment.

The agency linked to the ice loss is a measured warming of the southern ocean that is reducing the sea ice, which in turn holds back the flow of ice on land. So glaciers are melting, and flowing towards the sea at a faster rate.

“The fact that West Antarctic ice melt is still accelerating is a big deal because it’s increasing its contribution to sea level rise,” Dr Harig says. “It really has the potential to be a runaway problem.

“It has come to the point that if we continue losing mass in those areas, the loss can generate a self-reinforcing feedback, whereby we will be losing more and more ice, ultimately raising sea levels.” – Climate News Network

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Flood risk to nuclear sites raises meltdown fears

Flood risk to nuclear sites raises meltdown fears

Sea level rise, storm surges and bursting dams all pose an increasing danger to nuclear power stations as the climate changes.

LONDON, 5 May, 2015 – Safety checks following the Fukushima disaster in Japan in March 2011, when a 10 metre-high sea wall was overtopped by a tsunami, have shown that nuclear plants are at greater risk of catastrophic flooding as a result of climate change.

All nuclear plants need large quantities of water for cooling so all must be built close to the sea, large rivers or lakes. This makes them vulnerable to sea level rise, storm surges and to the possible collapse of large dams upstream from poor construction, floodwater or seismic activity.

Since nuclear plants are designed to operate for as long as 60 years and need around a further century to decommission, accelerating sea level rise and more intense rainfall may present serious problems.

There are currently 435 operating nuclear reactors in the world, many of them potentially vulnerable to flooding because of natural disasters. Examples from the UK, Finland and the US show that the extent of the danger is not always being disclosed.

In Britain, after discovering in May 2013 that one of their reactors would be at risk during a storm of inundation by seawater, the owners, EDF Energy, quietly shut it down. The reactor, at Dungeness and built on a shingle beach beside the English Channel, supplies 750,000 homes.

The company informed the Office for Nuclear Regulation that it was being shut down as a precaution. The reactor remained off-line until 15 October that year while a new sea wall was constructed – losing the company around £100 million in revenue.

Serious problem

Although the company did announce the closure at the time, the extent of the problem and the length of the shutdown were not announced. Later EDF admitted that the emergency works had taken place following an assessment of the flooding danger after the Fukushima disaster.

Stephen Thomas, professor of energy policy at the university of Greenwich in London,
criticised EDF for its attitude. He was quoted by the UK’s Independent newspaper as saying: “If a plant closes for five months it is not just fiddling about, it is something serious, and EDF can’t pretend it is not…we need to be told the truth.”

The same fears were raised in the US by the Union of Concerned Scientists after a report was leaked about the danger to nuclear reactors from dams bursting. According to a report by the US Nuclear Regulatory Authority (NRC), which had been withheld, more than 30 nuclear installations were in danger from flooding. The Commission was later accused of using security concerns to mask embarrassing information.

Higher odds

Among many revelations in the report was the fact that the authorities had known for a decade or more that the failure of a dam upstream from the Oconee nuclear plant in South Carolina would cause floodwater to overwhelm its three reactors, possibly causing a catastrophic meltdown. The odds of the dam bursting were far higher than the chances of the accident that devastated Fukushima.

Oconee is one of the largest nuclear plants in America and has been operating since 1983. Its owner, Duke Energy, remains confident that it could shut the plant down safely in an hour, before floodwaters from upstream could reach the reactors. The NRC has decided that this is sufficient safeguard.

Dave Lochbaum, director of the Nuclear Safety Project at the Union of Concerned Scientists, said: “The NRC knows – and has known for many years – that flooding from dam failures can disable the emergency equipment needed to prevent reactor core meltdown.

“The risk of a serious nuclear accident remains always above zero as a result of unexpected phenomena taking place”

“The agency must require plants to address known flooding hazards and thoroughly investigate other plants that may be at risk and require them to resolve any potential hazards.

“If such a flooding accident occurred, the NRC would quickly determine which other plants were vulnerable and require them to strengthen their protection against similar events. Wouldn’t it be smarter for the agency to do that before an accident occurs?”

More open about its problems is Finland’s Loviisa nuclear power plant on the Baltic Sea, which was flooded by a 1.73-metre storm surge in 2005. Since then four cooling towers have been built 10 metres above sea level to avoid inundation in a new storm surge, and new floodgates and waterproof doors have been installed to protect the reactor. A new road has been built above flood level so that emergency services can reach the plant to pump away floodwater.

Even so, the Rain Project, a consortium of experts on safety and climate change, thinks more can be done to protect against potential disaster. Christer Pursianen is professor of societal safety and environment at the Arctic University of Norway.

He says that although Finland is in the forefront of nuclear safety, more needs to be done to train staff in emergencies and to develop  links with neighbouring countries so as to gain experience in disaster prevention: “The risk of a serious nuclear accident remains always above zero as a result of unexpected phenomena taking place.” – Climate News Network

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Scientists zero in on only solution to climate crisis

Scientists zero in on only solution to climate crisis

Panel of international climate scientists says the world has only until 2050 to become a zero-carbon society − but the rewards for doing so would be immense.

LONDON, 22 April, 2015 – If you want to know what we have to do to avoid catastrophic climate change, 17 of the world’s leading climate scientists have worked out a simple but challenging solution: the world, they say, must turn by mid-century into a zero-carbon society.

The signatories to today’s “Earth Statement” say: “This trajectory is not one of economic pain, but of economic opportunity, progress and inclusiveness. It is a chance too good to be missed.

“The latest science indicates that there are critical thresholds in the Earth system. Transgressing them may lead to dramatic and irreversible environmental changes.

“We are probably edging very close to such thresholds, and may already have crossed one with regard to melting of parts of Antarctica. Sea-level rise of more than one metre due to this event alone may be inevitable.”

Window of opportunity

They are convinced that time is short. “The window of opportunity is closing fast,” says Johan Rockström, chair of the Earth League, an international group of scientists from leading research institutions working on issues caused by climate change, natural resource depletion, land degradation and water scarcity.

“We are on a trajectory that will leave our world irrevocably changed, far exceeding the 2°C mark. This gamble risks disaster for humanity, with unmanageable sea-level rise, heat waves, droughts and floods.

“We would never consider this level of risk in any other walk of life, yet we seem prepared to take this risk with our planet. Conversely, the scientific evidence shows that we can create a positive future, but only with bold action now.”

The 2°C threshold is the limit beyond which world leaders have agreed to prevent global temperatures rising as climate change intensifies.

“For the sake of fairness, rich countries and progressive industries can and should take the lead and decarbonise well before mid-century”

The Earth League’s first Earth Statement is issued as a warning ahead of the UN climate conference in Paris in December − referred to by the UN Framework Convention on Climate Change as COP21, the 21st conference of the parties to the original climate treaty.

The League is supported in its statement − published today to mark Earth Day, an annual reinvigoration of the global environmental movement − by the Global Challenges Foundation.

Professor Jeffrey Sachs, director of the Earth Institute at Columbia University, US, and one of the authors of the statement, says: “COP21 is the moment of truth − the last chance to stay within the 2°C upper limit.

Quality of life

“The key to success is deep decarbonisation by mid-century. Our studies show that this can be accomplished, at modest cost, and with a significant improvement in the quality of life.”

The Earth Statement lists what it calls “eight essential elements of climate action”, which it says any agreement achieved in Paris in December should achieve in order to provide the world with a good chance of avoiding dangerous climate change.

They include the need for the process of deep decarbonisation to start immediately. One of the eight points, which may prove contentious, reads: “Equity is critical. Every country must formulate an emissions pathway consistent with deep decarbonisation.

“For the sake of fairness, rich countries and progressive industries can and should take the lead and decarbonise well before mid-century.”

Prof Rockström and Prof John Schellnhuber, a fellow Earth League member and director of the Potsdam Institute for Climate Impact Research, will present the Earth Statement tomorrow at the fourth Nobel Laureates Symposium on Global Sustainability in Hong Kong. – Climate News Network

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Canada will lose many glaciers as climate warms

Canada will lose many glaciers as climate warms

Climate change could cause many glaciers in western Canada to start to disappear by 2040, affecting people and places that depend on their water.

LONDON, 10 April, 2015 − As the world warms, many of the great frozen rivers of Canada will not just retreat, but could vanish altogether.

New research suggests that maritime glaciers in the far northwest might survive, but more than two-thirds of Canada’s existing glaciers in British Columbia and Alberta could be lost altogether by 2100.

Garry Clarke, a glaciologist at the University of British Columbia in Vancouver, says: “Soon our mountains could look like those in Colorado or California, and you don’t see much ice in those landscapes.”

The consequences for the forests, grasslands, animals and communities that depend on glacial meltwater could be serious. The disappearance of the glaciers will also create problems for Canada’s hydroelectric industry, for agriculture and grazing, for the mining industry, for the salmon fishery, and for tourism.

Professor Clarke and his colleagues report in Nature Geoscience that they devised a model – a high-resolution computer simulation – of the glaciers of western Canada that explicitly mimicked glacial flow. Then they tested it with a range of scenarios for climate change, driven by human combustion of fossil fuels and rising atmospheric carbon dioxide levels in the last two centuries.

“Once the glaciers are gone, the streams will be a lot warmer and this will hugely change freshwater habitat”

There are more than 17,000 glaciers in British Columbia and Alberta, covering more than 26,000 square kilometres of the two provinces, and holding an estimated 2,980 cubic kilometres of ice. This puts western Canada as more glaciated than the Himalayas (which have less than 23,000 sq kms of glacier): the entire continent of South America has only 31,000 sq kms of glacier.

The researchers found that maritime glaciers in the northwest would endure, in a diminished state. But overall, the volume of the glaciers in western Canada would shrink by 70%, give or take 10%.

Right now glaciers, most of them between 100 and 200 metres thick, are thinning at a rate of about a metre a year. The peak flow of meltwater would most likely occur between 2020 and 2040. Thereafter, the rivers would be in decline.

Potential sea level rise as a consequence of this, the scientists say, would be “modest” at around 6mm, but the consequences for that part of Canada would be substantial.

The Columbia River, which flows from the interior to the Pacific coast of Washington and Oregon, yields the largest hydroelectric production of any river in North America. And the impact on freshwater ecosystems could be considerable.

“These glaciers act as a thermostat for freshwater systems,” said Professor Clarke. “Once the glaciers are gone, the streams will be a lot warmer and this will hugely change freshwater habitat. We could see some unpleasant surprises in terms of salmon productivity.” – Climate News Network

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