Antarctic ice sheet is result of carbon dioxide decrease, not continental breakup

Antarctic Peninsula.

Credit: © adfoto / Fotolia

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Climate modelers from the University of New Hampshire have shown that the most likely explanation for the initiation of Antarctic glaciation during a major climate shift 34 million years ago was decreased carbon dioxide (CO₂) levels. The finding counters a 40-year-old theory suggesting massive rearrangements of Earth’s continents caused global cooling and the abrupt formation of the Antarctic ice sheet. It will provide scientists insight into the climate change implications of current rising global CO₂ levels.

• Suzanne Goldenberg
• theguardian.com, Tuesday 29 July 2014 20.00 AEST
• Jump to comments (328)

The White House has warned that delaying action on climate change would carry a heavy price, racking up an additional 40% in economic losses from climate impacts and other costs over the course of 10 years.

White House officials said the stark finding from the president’s council of economic advisers underlined the urgency of Barack Obama’s efforts to cut carbon pollution.

In addition to a new report on the economic cost of delay, the White House is poised to launch two new initiatives on Tuesday dealing with fast-rising methane emissions from the natural gas industry, and buffering food security against future climate change.

“We are pushing across the board on the elements of the climate action plan,” John Podesta, Obama’s counsellor, told a conference call with reporters.

Several former treasury secretaries and a couple of billionaires have come forward in recent weeks to warn Americans about the economic risks of climate change. By producing its own report on the costs of climate change, the White House appeared to be moving to bolster Obama’s climate agenda from industry attacks.

Industry groups claim that new Environmental Protection Agency rules for power plants will cripple the economy.

In their rebuttal, Obama’s economic team said the costs of delaying action to cut carbon pollution would be far higher in the long term – 40% over the course of a decade, in terms of the increased costs of cutting greenhouse gas emissions and dealing with climate impacts.

The costs were projected to rise even more steeply with each additional degree of warming above the 2C threshold for dangerous climate change, the report said.

“Each decade we delay acting results in an added cost of dealing with the problem of an extra 40%,” Jason Furman, chairman of the council of economic advisers, told a conference call with reporters. “The total amount we would have to pay today would be 40% larger if we waited a decade instead of acting now.”

Additional costs of adapting to climate change caused by delaying action to cut emissions

Delaying action would deepen the risks to property and livelihoods. It would also make it more costly to reduce greenhouse gas emissions.

A 3C rise above pre-industrial levels would shave about 0.9% a year off global GDP, or about $150 billion a year, the report said. A 4C rise would cost the global economy 3.1% of global GDP a year, it said.

“The cost …..ramps up potentially astronomically to the point that even if you want to you couldn’t actually stabilise the temperature,” Furman said.

Furman said the finding was based on an analysis of 16 different economic models, and took into consideration economic damage due to climate change, and lost investment and other opportunities.

The report – and the other interventions – appeared timed to build support around the main pillar of Obama’s climate action plan, regulations limiting carbon pollution from power plants.

The EPA is holding public hearings in Atlanta, Denver, Pittsburgh and Washington DC this week on regulations to cut carbon pollution from power plants by 30% over the next 16 years.

The EPA regulations, which target the country’s largest single source of carbon dioxide emissions, are the main pillar of Obama’s climate plan – one of the signature issues of his second term – and by default contentious.

More than 1,600 people have signed up to speak at the hearings, and 300,000 have sent in written comments. Some 680 groups have signed up to lobby the EPA, according to the Center for Responsive Politics – more than any other government department.

The regulations are critical to Obama’s commitment to the international community to cut greenhouse gas emissions 17% on 2005 levels by 2020.

The EPA Administrator, Gina McCarthy, told reporters on Monday that she expected opponents to focus on the economy. “We are bound to hear this week and beyond that EPA actions are bad for the economy,” she said.

Industry groups, such as the American Petroleum Institute and the American Coalition for Clean Coal Electricity, accuse the EPA of waging a “war on coal” and say the regulations will damage the economy.

A Republican congressman, Mike Kelly, likened the regulations to terrorism, in an event at the conservative Heritage Foundation on Monday. “You talk about terrorism, you can do it in a lot of different ways,” he said. “But you terrorise the people who supply everything this country needs to be great – and you keep them on the sidelines – my goodness what have we become?”

Opponents of the EPA regulations also argue that they will be ineffective unless China and other big emitters also take action on climate change.

But McCarthy told the call America had to take actions at home to cut carbon pollution “or a global solution on climate change won’t make it to the table”.

She said there were already signs that the EPA regulations had encouraged China and other countries to do more to cut their own emissions.

The White House, the EPA Senate Democrats, economists, and environmental groups argue the regulations represent an opportunity – and that it would be far more costly to delay action.

The former treasury secretary, Robert Rubin, wrote in the Washington Post last week that framing the regulations as a trade-off between the environment and the economy was as false choice.

“The real question should be: What is the cost of inaction? In my view — and in the view of a growing group of business people, economists, and other financial and market experts — the cost of inaction over the long term is far greater than the cost of action,” Rubin wrote.

Senate Democrats are expected to expand on that argument at a budget committee hearing on Tuesday called “The costs of inaction: the economic and budgetary consequences of climate change”.

European and British economists have warned for years about the costs of inaction on climate change, with Nicholas Stern coming out with his landmark report in 2006.

But those findings did not get wide airing in the American media until earlier this year when a group of billionaires and former treasury secretaries came out with their report, Risky Business, on the costs of ignoring the climate problem.

Meanwhile, the Obama administration will on Tuesday announce a number of new initiatives on containing fast-rising emissions of methane from the natural gas industry.

The White House is also due to announce a new effort by companies such as Microsoft and Coca Cola on plans to help protect food production.

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Methane mega flare event on the Laptev Sea slope of the Arctic Ocean, at a depth of about 62 meters. Image via Daily Kos via University of Stockholm.

An international team of scientists aboard the icebreaker Oden – currently north of eastern Siberia, in the Arctic Ocean – is working primarily to measure methane emissions from the Arctic seafloor. On July 22, 2014, only a week into their voyage, the team reported “elevated methane levels, about 10 times higher than background seawater.” They say the culprit in this release of methane, a potent greenhouse gas, may be a tongue of relatively warm water from the Atlantic Ocean, the last remnants of the Gulf Stream, mixing into the Arctic Ocean. A press release from University of Stockholm described the discovery as:

… vast methane plumes escaping from the seafloor of the Laptev continental slope. These early glimpses of what may be in store for a warming Arctic Ocean could help scientists project the future releases of the strong greenhouse gas methane from the Arctic Ocean.

The scientists refer to the plumes as methane mega flares.

Click here to see where the icebreaker Oden is right now.

Expedition of the icebreaker Oden – called the SWERUS expedition – preliminary cruise plan and study areas of Leg 1 and 2. EEZ=Exclusive Economic Zone; LR=Lomonosov Ridge; MR=Mendeleev Ridge; HC=Herald Canyon; NSI=New Siberian Islands. Image via Daily Kos via University of Stockholm.

On July 22, 2014, chief scientist Örjan Gustafsson of the University of Stockholm wrote about the methane mega flare event in his blog. He wrote:

So, what have we found in the first couple of days of methane-focused studies?

1) Our first observations of elevated methane levels, about ten times higher than in background seawater, were documented already as we climbed up the steep continental slope at stations in 500 and 250 meter depth. This was somewhat of a surprise. While there has been much speculation of the vulnerability of regular marine hydrates [frozen methane formed due to high pressure and low temperature] along the Arctic rim, very few actual observations of methane releases due to collapsing Arctic upper slope marine hydrates have been made. ¨

It has recently been documented that a tongue of relatively warm Atlantic water, with a core at depths of 200–600 meters may have warmed up some in recent years. As this Atlantic water, the last remnants of the Gulf Stream, propagates eastward along the upper slope of the East Siberian margin, our SWERUS-C3 program is hypothesizing that this heating may lead to destabilization of upper portion of the slope methane hydrates. This may be what we now for the first time are observing.

2) Using the mid-water sonar, we mapped out an area of several kilometers where bubbles were filling the water column from depths of 200 to 500 meters. During the preceding 48 hours we have performed station work in two areas on the shallow shelf with depths of 60-70m where we discovered over 100 new methane seep sites. SWERUS-C3 researchers have on earlier expeditions documented extensive venting of methane from the subsea system to the atmosphere over the East Siberian Arctic Shelf. On this Oden expedition we have gathered a strong team to assess these methane releases in greater detail than ever before to substantially improve our collective understanding of the methane sources and the functioning of the system. This is information that is crucial if we are to be able to provide scientific estimations of how these methane releases may develop in the future.

While not as long-lasting in the atmosphere as carbon dioxide, methane is much more effective than carbon dioxide at trapping heat in Earth’s atmosphere. Climate scientists discuss a potential feedback loop regarding methane’s role in global warming. That is, as Earth’s climate warms, methane that is frozen in reservoirs stored in Arctic tundra soils – or marine sediments – may be released into the atmosphere, where it warm Earth still more, releasing more methane, and so on.

Methane release from the Arctic Ocean is not a new phenomenon; after all, the Stockholm scientists were there to measure it. U.S. scientists have observed Arctic Ocean methane release, too. For example, NASA reported in April 2012 on a study in which scientists measured surprising levels of methane coming from cracks in Arctic sea ice and areas of partial sea ice cover.

Methane bubbles discovered on Laptev continental slope of Arctic Ocean by the science team aboard the icebreaker Oden. Image via University of Stockholm.

On July 23, Ulf Hedman – who is aboard the Oden and who is Science Coordinator for the Swedish Polar Research Secretariat – gave a vivid description of the discovery in his blog:

We are ‘sniffing’ methane. We see the bubbles on video from the camera mounted on the CTD or the Multicorer. All analysis tells the signs. We are in a [methane] mega flare. We see it in the water column we read it above the surface an we follow it up high into the sky with radars and lasers. We see it mixed in the air and carried away with the winds. Methane in the air. Where does it come from? Is it from the old moors and mosses that used to be on dry land but now has sunken into the sea. Does it come from the deep interior of the Earth following structures in the bedrock up into the sand filled reservoirs collecting oil and gas then leaking out upwards, as bubbles through the sea bed into the water, into the mid-water sonar, the Niskin bottles the analysis and into our results?

Where does the methane come from? Is it organic or not? What’s the volume? How much is carried up into the air? Is there an effect on the climate? One mega flare does not tell the truth. It’s not evidence enough.

We carry on for the next station.

And the next, and next, next…

Bottom line: A team of international scientists aboard the icebreaker Oden has documented “elevated methane levels, about ten times higher than in background seawater” in the Arctic Ocean. They are calling it a methane mega flare event and express hopes it will help them project future releases of the strong greenhouse gas methane from the Arctic Ocean, and to understand the role this released methane might play in global warming.

Broken Arctic sea ice as seen from a window in from a U.S. Coast Guard flight over the Beaufort Sea in the Arctic Ocean in 2009. (Yereth Rosen/Reuters)

Big waves like those fit for surfing are not what we think of when contemplating the Arctic Ocean. The water is ice-covered most of the time — and it takes large expanses of open sea plus wind to produce mighty surf.

So the fact that researchers have now measured swells of more than 16 feet in the Arctic’s Beaufort Sea, just north of Alaska, is a bit of a stunner. Swells of that size, researchers say, have the potential to break up Arctic ice even faster than than the melt underway there for decades thanks to rapid global warming.

The wave measurements, using sensors beneath the surface communicating via satellite, were recorded by Jim Thomson of the University of Washington and W. Erick Rogers of the Naval Research Laboratory in 2012 and reported in an article in Geophysical Research Letters this year.

“The observations reported here are the only known wave measurements in the central Beaufort Sea,” they wrote, “because until recently the region remained ice covered throughout the summer and there were no waves to measure.”

Sixteen feet was the average during a peak period, Thomson said in an email. “The largest single wave was probably” 9 meters, or about 29 feet, he said. The average over the entire 2012 season was 3 to 6 feet.

Satellite images of polar ice sheets taken in 2001 and 2007 show retreating ice in the Beaufort Sea during summer in the Arctic Ocean. (Photo by USGS via Getty Images)

The distances of open water change “dramatically throughout the summer season, from essentially zero in April to well over 1000 km in September,” they reported. “In recent years, the seasonal ice retreat has expanded dramatically, leaving much of the Beaufort Sea ice free at the end of the summer.”

Because swells carry more energy, they reported, they will likely increase the pace of ice breakup in the region, eventually producing an “ice-free summer, a remarkable departure from from historical conditions in the Arctic, with potentially wide-ranging implications for the air-water-ice system and the humans attempting to operate there.”

“Waves could accelerate the ice retreat,” Thomson said in his email from a village on the Arctic, where he was getting read to deploy some wave buoys.  “We don’t have much direct evidence of this, or knowledge of the relative importance compared with melting, but the process is real.  We are conducting a large project this summer to answer just that question”