Exceptional Slowdown in North Atlantic Ocean Conveyor Reported

4 04 2015
26.03.2015 15:18 Age: 9 days
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Click to enlarge. This image shows the Atlantic Conveyor: a graph of the Atlantic Meridional Overturning Circulation. Courtesy: Stefan Rahmstorf, PIK.

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Click to enlarge. The blue cooling spot south of Greenland: NASA GISS warming map 1901-2013. Courtesy: NASA

From the Potsdam Institute for Climate Impact Research (PIK)

The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe. Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been weaker than ever before in the last century, or even in the last millennium. The gradual but accelerating melting of the Greenland ice-sheet, caused by man-made global warming, is a possible major contributor to the slowdown. Further weakening could impact marine ecosystems and sea level as well as weather systems in the US and Europe.

“It is conspicuous that one specific area in the North Atlantic has been cooling in the past hundred years while the rest of the world heats up,” says Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, lead author of the study to be published in Nature Climate Change. Previous research had already indicated that a slowdown of the so-called Atlantic meridional overturning circulation might be to blame for this. “Now we have detected strong evidence that the global conveyor has indeed been weakening in the past hundred years, particularly since 1970,” says Rahmstorf.

Because long-term direct ocean current measurements are lacking, the scientists mainly used sea-surface and atmospheric temperature data to derive information about the ocean currents, exploiting the fact that ocean currents are the leading cause of temperature variations in the subpolar north Atlantic. From so-called proxy data – gathered from ice-cores, tree-rings, coral, and ocean and lake sediments – temperatures can be reconstructed for more than a millennium back in time. The recent changes found by the team are unprecedented since the year 900 AD, strongly suggesting they are caused by man-made global warming.

“The melting Greenland ice sheet is likely disturbing the circulation”

The Atlantic overturning is driven by differences in the density of the ocean water. From the south, the warm and hence lighter water flows northwards, where the cold and thus heavier water sinks to deeper ocean layers and flows southwards. “Now freshwater coming off the melting Greenland ice sheet is likely disturbing the circulation,” says Jason Box of the Geological Survey of Denmark and Greenland. The freshwater is diluting the ocean water. Less saline water is less dense and has therefore less tendency to sink into the deep. “So the human-caused mass loss of the Greenland ice sheet appears to be slowing down the Atlantic overturning – and this effect might increase if temperatures are allowed to rise further,” explains Box.

The observed cooling in the North Atlantic, just south of Greenland, is stronger than what most computer simulations of the climate have predicted so far. “Common climate models are underestimating the change we’re facing, either because the Atlantic overturning is too stable in the models or because they don’t properly account for Greenland ice sheet melt, or both,” says Michael Mann of Pennsylvania State University in the US. “That is another example where observations suggest that climate model predictions are in some respects still overly conservative when it comes to the pace at which certain aspects of climate change are proceeding.”

The cooling above the Northern Atlantic would only slightly reduce the continued warming of the continents. The scientists certainly do not expect a new ice age, thus the imagery of the ten-year-old Hollywood blockbuster ‘The Day After Tomorrow’ is far from reality. However, it is well established that a large, even gradual change in Atlantic ocean circulation could have major negative effects.

“If the slowdown of the Atlantic overturning continues, the impacts might be substantial,” says Rahmstorf. “Disturbing the circulation will likely have a negative effect on the ocean ecosystem, and thereby fisheries and the associated livelihoods of many people in coastal areas. A slowdown also adds to the regional sea-level rise affecting cities like New York and Boston. Finally, temperature changes in that region can also influence weather systems on both sides of the Atlantic, in North America as well as Europe.”

If the circulation weakens too much it can even break down completely – the Atlantic overturning has for long been considered a possible tipping element in the Earth System. This would mean a relatively rapid and hard-to-reverse change. The latest report by the Intergovernmental Panel on Climate Change (IPCC) estimates there to be an up to one-in-ten chance that this could happen as early as within this century. However, expert surveys indicate that many researchers assess the risk to be higher. The study now published by the international team of researchers around Rahmstorf provides information on which to base a new and better risk assessment.

Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970. Since 1990 the AMOC seems to have partly recovered. This time evolution is consistently suggested by an AMOC index based on sea surface temperatures, by the hemispheric temperature difference, by coral-based proxies and by oceanic measurements. We discuss a possible contribution of the melting of the Greenland Ice Sheet to the slowdown. Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium (p > 0.99). Further melting of Greenland in the coming decades could contribute to further weakening of the AMOC.

Evidence for an exceptional 20th-Century slowdown in Atlantic Ocean overturning by Rahmstorf, S., Box, J., Feulner, G., Mann, M., Robinson, A., Rutherford, S., Schaffernicht, E. published in Nature Climate Change, DOI:10.1038/nclimate2554.

Read the abstract and get the paper here.

 PIK news release issued here.

 Our story AMOC Is Highly Variabble And Declining Says Study here.

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NEB’s “Public Comment” Doesn’t Include Public or Climate Change

29 01 2015

Dear friends across Canada,

In days, the National Energy Board will start public consultations that could decide the fate of the eastern oil sands pipeline.But they want to freeze out discussion of climate change, and limit the number of people they hear from. Now citizens’ groups are coming together to build an enormous combined call for full and fair hearings — click now to join and tell everyone!

SIGN THE PETITION

A group of energy sector insiders look set to rubber stamp the eastern oil sands pipeline, which will cross rivers and cut through communities from Alberta to Québec and New Brunswick — choking the climate, and risking spills of up to 2.6 million litres of oil. 

Shockingly, they say that climate change isn’t their concern.

The good news is that the National Energy Board is about to start public consultations before this crucial decision is made — but they only want to hear from a hand picked few, on topics that they choose.

Right now, citizens’ groups are coming together to make the biggest push yet for a fair and inclusive process that will look at all the issues — if we all add our voices, they will have to listen, or risk a complete loss of public faith.

We only have days before the process starts. Click now to tell these decision makers to put their rubber stamp back in their pockets, and instead protect our precious natural resources and the climate. When 100,000 sign on, Avaaz will bring all our voices right to the NEB’s doorstep in Calgary.

https://secure.avaaz.org/en/canada_pipeline_neb_e/?buMQMib&v=52485

PM Harper’s government has tethered our economy to the oil industry, they’ve described the National Energy Board as an “ally”, and they advise on appointments to the board.

But the NEB is supposed to be independent, and they are required to hear from people impacted by these mega projects. This should include people impacted by the devastating effects of climate change too.

The NEB says that climate change isn’t its concern, and that the provinces, together with pipeline-builder TransCanada, should deal with it. But it’s taking a narrow look at only the oil transportation issues, and not at the pipeline’s role in unleashing carbon from the tar sands on the world. Building this pipeline means digging ourselves further into a downward spiral of oil dependency and its impact on our changing climate needs to be reviewed.

New studies show that the pipeline, which will transport over 1 million barrels of tar sands crude each day, is vulnerable to corrosion, cracking, and massive spills. The Ontario-commissioned studies also say that the pipeline doesn’t provide the economic benefits that have been claimed, and there could be impacts on drinking water.

The National Energy Board could decide that the project is simply too risky for Canadians to bear. As they prepare for public consultation, let’s make sure that they hear from as many people as possible, and look at all the impacts of this oily pipeline. Click now to take action:

https://secure.avaaz.org/en/canada_pipeline_neb_e/?buMQMib&v=52485

Late last year, pipeline company TransCanada hired a giant PR firm that suggested targeting Avaaz and other organisations. We won’t be intimidated by this dirty war! By raising our voices together, we can show the NEB that thousands of Canadians demand fair and open hearings on this massive project.

With hope,

Jo, Ari, Danny, Emma, Ricken, and the whole Avaaz team

SOURCES

National Energy Board’s pipeline focus isn’t climate change, CEO says (CBC)
http://www.cbc.ca/news/canada/new-brunswick/national-energy-board-s-pipeline-focus-isn-t-climate-change-ceo-says-1.2847487

Poll shows few Quebecers support Energy East pipeline (Montreal Gazette)
http://montrealgazette.com/news/local-news/poll-shows-few-quebecers-support-energy-east-pipeline

City raises pipeline concerns (Winnipeg Free Press)
http://www.winnipegfreepress.com/local/city-raises-pipeline-concerns-252590031.html

More details needed on impact of Energy East pipeline, report says (Toronto Star)
http://www.thestar.com/news/world/2015/01/15/more-details-needed-on-impact-of-energy-east-pipeline-report-says.html

Energy East pipeline benefits overblown, report says (CBC)
http://www.cbc.ca/news/business/energy-east-pipeline-benefits-overblown-report-says-1.2576782

TransCanada pressuring opponents of Energy East pipeline, documents show (Toronto Star)
http://www.thestar.com/news/world/2014/11/18/transcanada_pressuring_opponents_of_energy_east_pipeline_documents_show.html





2 Degrees C: Tar Sands Must Stay in the Ground

9 01 2015

85% of tar sands must stay in the ground to limit climate change to 2 degrees Celsius

With Prime Minister Stephen Harper’s environment minister meeting with provincial and territorial leaders to discuss post-2020 carbon emission targets in late February, the federal election this October, the pivotal United Nations climate summit in December, and a federal government decision expected on the Energy East pipeline just a few month later by May 2016, the release yesterday of a new report on what Canada must to do to limit climate change to 2 degrees Celsius is of critical importance.

The Canadian Press reports, “British researchers [from University College London] have concluded that most of Canada’s [tar] sands will have to be left in the ground if the world gets serious about climate change. The report, published in the journal Nature, says three-quarters of all Canada’s oil reserves and 85 per cent of its [tar] sands can’t be burned if the world wants to limit global warming.”

“The report also concludes that no country’s Arctic energy resources can be developed if global temperature increases are to be kept manageable. It adds that about one-quarter of Canada’s natural gas reserves and four-fifths of its coal would also have to be left in the ground.”

CBC adds, “[The study] says for the world to have a reasonable prospect of meeting the target, no more than 7.5 billion barrels of oil from the [tar] sands can be produced by 2050 — a mere 15 per cent of viable reserves and only about one per cent of total bitumen.” And the Globe and Mail further notes, “Domestic estimates of Alberta’s oil reserves come in at about 168 billion barrels, with hundreds of billions more available for extraction if future oil prices make the resource more attractive. The study uses a more conservative estimate of 48 billion barrels as the current reserve and then finds that only 7.5 billion barrels of that, or about 15 per cent, can be used by 2050 as part of the global allotment of fossil-fuel use in a two-degree scenario.”

In response to this study, Natural Resources Canada said, “The majority [of the world’s energy] will come from fossil fuels, even under its most stringent greenhouse gas reduction forecast. The choice is whether to use energy from a secure, environmentally responsible, transparent country like Canada, or to seek energy from less stable countries without responsible environmental policies.” And Andrew Leach, the Enbridge Professor of Energy Policy at the University of Alberta, says that even using 25 per cent of Canada’s oil reserves between now and 2050 would lead to growth above current rates of production.

In terms of production, in early October 2014, Canada was exporting about 2.98 million barrels per day of crude to the United States. The Canadian Association of Petroleum Producers has said they expect oil production to reach 3.91 million barrels per day in 2015 and 6.44 million barrels per day by 2030. And in terms of meeting our carbon emission target, the Globe and Mail has reported that documents submitted by the Harper government to the United Nations in December 2013, “show that, without further policy action, Canada’s emissions would be 734 megatonnes by 2020, or 20 per cent higher than the target of 612 megatonnes [that the Harper government agreed to at the United Nations climate summit in 2009].”

The Council of Canadians is against the proposed Keystone XL, Northern Gateway, Energy East, Trans Mountain and Arctic Gateway pipelines. Together, those pipelines would move about 3.45 million barrels of oil per day or about 1.26 billion barrels a year. If all of these pipelines were to become operational, they would exceed the 7.5 billion barrel limit noted in this British study in less than six years.

And as now supported by this study, we have called for a moratorium on the offshore extraction of oil and gas from Arctic, an end to fracking, and opposed coal export terminals in British Columbia. As an alternative, we have called for the development of sustainable energy sources in a joint report with the Canadian Labour Congress titled Green, Decent and Public.

We were also present for the climate talks in Lima in 2014, Cancun in 2010 and Copenhagen in 2009. At those summits, we called on the Harper government to commit to an emissions reduction target of at least 40 per cent below 1990 levels by 2020. We have also stated that Canada’s fair contribution to climate adaptation for the Global South should be $4 billion yearly. And we have argued for inclusion and a democratization of the climate change negotiations process. The next United Nations climate summit – COP 21 – will take place November 30 to December 11 in Paris.

Further reading
85% of oilsands can’t be burned if world to limit global warming: report (Canadian Press)
Climate change study says most of Canada’s oil reserves should be left underground (CBC)
Oil sands must remain largely unexploited to meet climate target, study finds (The Globe and Mail)

 





CATHOLIC BISHOPS FROM EVERY CONTINENT CALL FOR ‘AN END TO THE FOSSIL FUEL ERA

29 12 2014

 POSTED ON DECEMBER 11, 2014 AT 4:45 PM UPDATED: DECEMBER 12, 2014 AT 9:05 AM

Catholic Bishops From Every Continent Call For ‘An End To The Fossil Fuel Era’

Pope Francis and a group of bishops at the Vatican.

Pope Francis and a group of bishops at the Vatican.

CREDIT: AP PHOTO / ALESSANDRA TARANTINO

A group of Catholic Bishops called on the world’s governments to end fossil fuel use on Wednesday, citing climate change’s threat to the global poor as the lodestar of their concern.

According to the BBC, the statement is the first time senior officials in the Church from every continent have issued such a call. The statement also drops in the middle of ongoing international climate talks in Lima, Peru, as countries continue to hash out what to do about climate change in the run-up to a summit in 2015, where observers and activists hope a new international agreement will be finalized.

“We express an answer to what is considered God’s appeal to take action on the urgent and damaging situation of global climate warming,” the bishops wrote.

Striking a similar note to Naomi Klein’s recent book, “This Changes Everything,” the bishops’ statement also argued that global capitalism and its economic systems, as currently designed, are incompatible with long-term ecological sustainability: “The main responsibility for this situation lies with the dominant global economic system, which is a human creation. In viewing objectively the destructive effects of a financial and economic order based on the primacy of the market and profit, which has failed to put the human being and the common good at the heart of the economy, one must recognize the systemic failures of this order and the need for a new financial and economic order.”

The document calls on the international community to “adopt a fair and legally binding global agreement” to cut carbon emissions at the summit in Paris next year. Specifically, the bishops insist on limiting global temperature rise to 1.5°C relative to pre-industrial levels — a considerably more ambitious goal than the 2°C ceiling that’s generally agreed on as the threshold beyond which climate change becomes truly dangerous — and on building “new models of development and lifestyles that are both climate compatible” and can “bring people out of poverty.”

“Central to this is to put an end to the fossil fuel era, phasing out fossil fuel emissions and phasing in 100 percent renewables with sustainable energy access for all.”

The goal of reducing global carbon emissions to zero is already making the rounds in Lima, and the Associated Press reports that dozens of governments are on board with the idea. At its current rate of emissions, the world will actually use up its “carbon budget” — the total amount of greenhouse gases it can emit this century and still stay under 2°C — by 2040, though slowing that rate in the coming years will extend the deadline.

The bishops’ logic and their goal for restraining temperature increase is rooted in prioritizing “the immediate needs of the most vulnerable communities.” Indeed, precisely because of their lack of resources and infrastructure, many of the globe’s poorest populations — particularly those in Southern Asia and Africa — are especially vulnerable to the droughts, floods, rising seas, storms, and other forms of extreme weather that are part and parcel of climate change. Meanwhile, a report released by the United Nations this past Friday determined that the amount poor and developing countries will have to collectively invest in adapting to climate change will run between $250 and $500 billion annually by 2050 even if the world does keep to the 2°C threshold. There’s also at least some scientific evidence that the effects of climate change at a 2°C rise will be considerably more severe than generally thought.

The U.N. report also determined that there is currently a massive gap between what the developing countries will need and what the developed world is willing to pay — a point of considerable tension in the international talks. While China has overtaken the United States as the biggest cumulative emitter, the U.S. maintains are far higher level of emissions per capita. Furthermore, climate change is cumulative, meaning the bulk of the effects are still driven by the carbon the U.S. and the rest of the western world historically emitted in the course of building their wealth. That greater wealth per person also means advanced countries have far more room to invest in cutting emissions and in aiding the still-developing neighbors.

“Those responsible for climate change have responsibilities to assist the most vulnerable in adapting and managing loss and damage and to share the necessary technology and knowhow,” the bishops continue, while insisting that 50 percent of all climate-related public funding go to meet the developing world’s adaptation needs.

While this is a first by some markers, the Bishops’ statement also continues a long tradition of engagement with environmental issues and climate change by the Catholic Church. Pope Francis himself has made the religious case for combating climate change, warning that “if we destroy Creation, Creation will destroy us!” Earlier this year, the Church held a five-day summit bringing together scientists, economists, philosophers, astronomers, and other experts to explore ways the Catholic church could address climate change and its related challenges. Francis has also singled out the destruction of the rainforest as a “sin,” as is working on an official papal encyclical tackling the environment and humanity’s relationship to it.





Fracking Moratorium Could Force Corridor Resources out of NB

20 12 2014

Hundreds of jobs at stake near Sussex, government says mine has other options

CBC News Posted: Dec 20, 2014 1:11 PM AT Last Updated: Dec 20, 2014 1:11 PM AT

A fracking moratorium in New Brunswick could affect hundreds of jobs by forcing Corridor Resources to leave the province, according to the natural gas and petroleum company.

President and CEO Steve Moran says Corridor Resources is still gauging the impact of the moratorium, but says if it lasts for a long period of time, the company may have to relocate outside of the province.

“We’ll have to move our capital and our expenditures elsewhere. We really don’t want to, but we’ll have no choice,” Moran said.

 Corridor Resources has been fracking near Sussex for a decade. The company co-owns a pipeline with PotashCorp that carries fracked gas to the new potash mine in Penobsquis, where about 450 people work.

The moratorium will prevent Corridor Resources from fracking for more gas to continue supplying the mine, according to Moran.

Premier Brian Gallant introduced the moratorium on Thursday,explicitly outlining five conditions that must be satisfied before the moratorium is lifted.

The moratorium will not be ‘grandfathered’ for companies with projects already underway.

“It’ll be up to them to see if there’s other ways to be able to continue their operations without the process of hydraulic fracturing,” Gallant said.

Energy Minister Donald Arseneault says the mine has other options.

“PotashCorp has other means as well to access gas as they’re connected to the Maritimes Northeast pipeline, ” Arsenault said.

The Maritimes and Northeast pipeline connects natural gas from developments from offshore Nova Scotia to markets in Atlantic Canada and the northeastern United States.

Arseneault also says Corridor Resources has several active wells that don’t need to be fracked in order to supply the PotashCorp mine.





Stanford: Pathways to 100% Renewable Energy

19 12 2014





Largest Tar Sands Pipeline to US Shut Down Indefinitely After Spill of 50,000+ Gallons

19 12 2014

Enbridge Inc., based in Calgary, Alta., has agreed to pay about $6.8 million to settle a class action in one of the costliest onshore oil spills in U.S. history. (photo: AP)
Enbridge Inc., based in Calgary, Alta., has agreed to pay about $6.8 million to settle a class action in one of the costliest onshore oil spills in U.S. history. (photo: AP)

By Scott Haggett, Reuters

18 December 14

nbridge Inc said on Thursday it has no restart date yet for its 796,000-barrel-per-day Line 4, the largest oil-export pipeline to the United States, after it was shut a day earlier after a spill of 1,350 barrels at its Regina, Saskatchewan, oil terminal.

Graham White, a spokesman for the company, said in an email the spill originated at a flange or valve within the terminal, so there were no problems with the pipeline itself. He said that could mean the problem is “a relatively easy fix”, but could not speculate on when the line would return to service.