Permafrost zones occupy nearly a quarter of the exposed land area of the Northern Hemisphere. NASA’s Carbon in Arctic Reservoirs Vulnerability Experiment is probing deep into the frozen lands above the Arctic Circle in Alaska to measure emissions of the greenhouse gases carbon dioxide and methane from thawing permafrost – signals that may hold a key to Earth’s climate future. Image credit: Hugo Ahlenius, UNEP/GRID-Arendal
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June 10, 2013
Flying low and slow above the wild, pristine terrain of Alaska’s North Slope in a specially instrumented NASA plane, research scientist Charles Miller of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., surveys the endless whiteness of tundra and frozen permafrost below. On the horizon, a long, dark line appears. The plane draws nearer, and the mysterious object reveals itself to be a massive herd of migrating caribou, stretching for miles. It’s a sight Miller won’t soon forget.
“Seeing those caribou marching single-file across the tundra puts what we’re doing here in the Arctic into perspective,” said Miller, principal investigator of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), a five-year NASA-led field campaign studying how climate change is affecting the Arctic’s carbon cycle.
“The Arctic is critical to understanding global climate,” he said. “Climate change is already happening in the Arctic, faster than its ecosystems can adapt. Looking at the Arctic is like looking at the canary in the coal mine for the entire Earth system.”
Aboard the NASA C-23 Sherpa aircraft from NASA’s Wallops Flight Facility, Wallops Island, Va., Miller, CARVE Project Manager Steve Dinardo of JPL and the CARVE science team are probing deep into the frozen lands above the Arctic Circle. The team is measuring emissions of the greenhouse gases carbon dioxide and methane from thawing permafrost — signals that may hold a key to Earth’s climate future.
What Lies Beneath
Permafrost (perennially frozen) soils underlie much of the Arctic. Each summer, the top layers of these soils thaw. The thawed layer varies in depth from about 4 inches (10 centimeters) in the coldest tundra regions to several yards, or meters, in the southern boreal forests. This active soil layer at the surface provides the precarious foothold on which Arctic vegetation survives. The Arctic’s extremely cold, wet conditions prevent dead plants and animals from decomposing, so each year another layer gets added to the reservoirs of organic carbon sequestered just beneath the topsoil.
Over hundreds of millennia, Arctic permafrost soils have accumulated vast stores of organic carbon – an estimated 1,400 to 1,850 petagrams of it (a petagram is 2.2 trillion pounds, or 1 billion metric tons). That’s about half of all the estimated organic carbon stored in Earth’s soils. In comparison, about 350 petagrams of carbon have been emitted from all fossil-fuel combustion and human activities since 1850. Most of this carbon is located in thaw-vulnerable topsoils within 10 feet (3 meters) of the surface.
But, as scientists are learning, permafrost – and its stored carbon – may not be as permanent as its name implies. And that has them concerned.
“Permafrost soils are warming even faster than Arctic air temperatures – as much as 2.7 to 4.5 degrees Fahrenheit (1.5 to 2.5 degrees Celsius) in just the past 30 years,” Miller said. “As heat from Earth’s surface penetrates into permafrost, it threatens to mobilize these organic carbon reservoirs and release them into the atmosphere as carbon dioxide and methane, upsetting the Arctic’s carbon balance and greatly exacerbating global warming.”
Current climate models do not adequately account for the impact of climate change on permafrost and how its degradation may affect regional and global climate. Scientists want to know how much permafrost carbon may be vulnerable to release as Earth’s climate warms, and how fast it may be released.
CARVing Out a Better Understanding of Arctic Carbon
Enter CARVE. Now in its third year, this NASA Earth Ventures program investigation is expanding our understanding of how the Arctic’s water and carbon cycles are linked to climate, as well as what effects fires and thawing permafrost are having on Arctic carbon emissions. CARVE is testing hypotheses that Arctic carbon reservoirs are vulnerable to climate warming, while delivering the first direct measurements and detailed regional maps of Arctic carbon dioxide and methane sources and demonstrating new remote sensing and modeling capabilities. About two dozen scientists from 12 institutions are participating.
“The Arctic is warming dramatically – two to three times faster than mid-latitude regions – yet we lack sustained observations and accurate climate models to know with confidence how the balance of carbon among living things will respond to climate change and related phenomena in the 21st century,” said Miller. “Changes in climate may trigger transformations that are simply not reversible within our lifetimes, potentially causing rapid changes in the Earth system that will require adaptations by people and ecosystems.”
The CARVE team flew test flights in 2011 and science flights in 2012. This April and May, they completed the first two of seven planned monthly campaigns in 2013, and they are currently flying their June campaign.
Each two-week flight campaign across the Alaskan Arctic is designed to capture seasonal variations in the Arctic carbon cycle: spring thaw in April/May, the peak of the summer growing season in June/July, and the annual fall refreeze and first snow in September/October. From a base in Fairbanks, Alaska, the C-23 flies up to eight hours a day to sites on Alaska’s North Slope, interior and Yukon River Valley over tundra, permafrost, boreal forests, peatlands and wetlands.
The C-23 won’t win any beauty contests – its pilots refer to it as “a UPS truck with a bad nose job.” Inside, it’s extremely noisy – the pilots and crew wear noise-cancelling headphones to communicate. “When you take the headphones off, it’s like being at a NASCAR race,” Miller quipped.
But what the C-23 lacks in beauty and quiet, it makes up for in reliability and its ability to fly “down in the mud,” so to speak. Most of the time, it flies about 500 feet (152 meters) above ground level, with periodic ascents to higher altitudes to collect background data. Most airborne missions measuring atmospheric carbon dioxide and methane do not fly as low. “CARVE shows you need to fly very close to the surface in the Arctic to capture the interesting exchanges of carbon taking place between Earth’s surface and atmosphere,” Miller said.
Onboard the plane, sophisticated instruments “sniff” the atmosphere for greenhouse gases. They include a very sensitive spectrometer that analyzes sunlight reflected from Earth’s surface to measure atmospheric carbon dioxide, methane and carbon monoxide. This instrument is an airborne simulator for NASA’s Orbiting Carbon Observatory-2 (OCO-2) mission to be launched in 2014. Other instruments analyze air samples from outside the plane for the same chemicals. Aircraft navigation data and basic weather data are also collected. Initial data are delivered to scientists within 12 hours. Air samples are shipped to the University of Colorado’s Institute for Arctic and Alpine Research Stable Isotope Laboratory and Radiocarbon Laboratory in Boulder for analyses to determine the carbon’s sources and whether it came from thawing permafrost.
Much of CARVE’s science will come from flying at least three years, Miller says. “We are showing the power of using dependable, low-cost prop planes to make frequent, repeat measurements over time to look for changes from month to month and year to year.”
Ground observations complement the aircraft data and are used to calibrate and validate them. The ground sites serve as anchor points for CARVE’s flight tracks. Ground data include air samples from tall towers and measurements of soil moisture and temperature to determine whether soil is frozen, thawed or flooded.
A Tale of Two Greenhouse Gases
It’s important to accurately characterize the soils and state of the land surfaces. There’s a strong correlation between soil characteristics and release of carbon dioxide and methane. Historically, the cold, wet soils of Arctic ecosystems have stored more carbon than they have released. If climate change causes the Arctic to get warmer and drier, scientists expect most of the carbon to be released as carbon dioxide. If it gets warmer and wetter, most will be in the form of methane.
The distinction is critical. Molecule per molecule, methane is 22 times more potent as a greenhouse gas than carbon dioxide on a 100-year timescale, and 105 times more potent on a 20-year timescale. If just one percent of the permafrost carbon released over a short time period is methane, it will have the same greenhouse impact as the 99 percent that is released as carbon dioxide. Characterizing this methane to carbon dioxide ratio is a major CARVE objective.
There are other correlations between Arctic soil characteristics and the release of carbon dioxide and methane. Variations in the timing of spring thaw and the length of the growing season have a major impact on vegetation productivity and whether high northern latitude regions generate or store carbon.
CARVE is also studying wildfire impacts on the Arctic’s carbon cycle. Fires in boreal forests or tundra accelerate the thawing of permafrost and carbon release. Detailed fire observation records since 1942 show the average annual number of Alaska wildfires has increased, and fires with burn areas larger than 100,000 acres are occurring more frequently, trends scientists expect to accelerate in a warming Arctic. CARVE’s simultaneous measurements of greenhouse gases will help quantify how much carbon is released to the atmosphere from fires in Alaska – a crucial and uncertain element of its carbon budget.
Early Results
The CARVE science team is busy analyzing data from its first full year of science flights. What they’re finding, Miller said, is both amazing and potentially troubling.
“Some of the methane and carbon dioxide concentrations we’ve measured have been large, and we’re seeing very different patterns from what models suggest,” Miller said. “We saw large, regional-scale episodic bursts of higher-than-normal carbon dioxide and methane in interior Alaska and across the North Slope during the spring thaw, and they lasted until after the fall refreeze. To cite another example, in July 2012 we saw methane levels over swamps in the Innoko Wilderness that were 650 parts per billion higher than normal background levels. That’s similar to what you might find in a large city.”
Ultimately, the scientists hope their observations will indicate whether an irreversible permafrost tipping point may be near at hand. While scientists don’t yet believe the Arctic has reached that tipping point, no one knows for sure. “We hope CARVE may be able to find that ‘smoking gun,’ if one exists,” Miller said.
Other institutions participating in CARVE include City College of New York; the joint University of Colorado/National Oceanic and Atmospheric Administration’s Cooperative Institute for Research in Environmental Sciences, Boulder, Colo.; San Diego State University; University of California, Irvine; California Institute of Technology, Pasadena; Harvard University, Cambridge, Mass.; University of California, Berkeley; Lawrence Berkeley National Laboratory, Berkeley, Calif.; University of California, Santa Barbara; NOAA’s Earth System Research Laboratory, Boulder, Colo.; and University of Melbourne, Victoria, Australia.
For more information on CARVE, visit: http://science.nasa.gov/missions/carve/ .
Alan Buis
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0474
Alan.buis@jpl.nasa.gov
2013-197
Image Credit: Donarreiskoffer
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Hi Antony, wondering if you would do an analysis for us here in the public of what happened to the Labor vote in NSW when they switched leaders to Kineally and where they ended up, compared to what happened in the Queensland election where Labor opted to stay with Bligh. It’d be interesting from an analytical point of view to see what happens to the vote when you switch leaders, compared to when you stick with one that’s unpopular because of a perceived lie.
Bligh made an error in the public service assets sale that she never recovered from which is very similar to what’s happened with Gillard’s carbon tax “promise”. I’m from Queensland so I’m not sure what the backdrop was in NSW where they continually switched leaders, but I’d sure be interested to look at these two scenarios that occurred from an analytical/mathematical point of view in what happens to the polling numbers.
COMMENT: Leadership was irrelevant in NSW. The Labor vote barely moved after both leadership changes, and the approval ratings of both Rees and Keneally declined continuously from their initial high figures.
Bligh’s rating bounced around in her last term and she was relatively popular given the size of the swing against the government.
Posted by: Spin Baby, Spin | June 10, 2013 at 02:35 PM
Antony if Rudd was to be reinstated by the ALP and Windsor (et al?) withdrew their formal support for the ALP wouldn’t that suggest to the GG that Rudd may not have the confidence of the House? If Rudd couldn’t demonstrate that confidence, ether by a vote on the floor or statements from enough of the INDs to give him a majority, wouldn’t he have to recommend to the GG an immediate HoR election (assuming all this happens pre 3/8) or force the GG to call one?
Probably moot as a returned PM Rudd would likely go to a snap Poll anyway to minimise the impact of the Coalition campaign. However, if he decided to go long without Windsor’s support i would’ve that might be tricky.
COMMENT: If Rudd returns as PM and the government is promptly defeated on the floor of the House, an immediate election means 27 July or 3 August, with the latter preferred because it allows a half-Senate election.
Once Parliament rises, the role of the Independents no longer matters. The House will be dissolved for an election before it is due to resume at the end of August.
Governor-Generals do not call elections, they accept advice to call them. A Prime Minister that continues to try and govern having lost a crucial vote in the House risks being dismissed, with a new Prime Minister being appointed to offer advice calling an election.
Posted by: wonk_arama | June 10, 2013 at 03:09 PM
Excellent analysis Antony, very useful. You mention that even if key independents desert the Gillard government immediately the election will still occur on 3 August. From what I understand above, for there to be a joint Half Senate and House of Reps election, parliament can not be dissolved before the 21st June. If it becomes apparent in the next few days that neither the ALP nor the Coalition has the confidence of the house, is the Governor General not obliged to dissolve the House of Reps immediately, forcing a July election? Or is it simply that there is enough time for the GG to delay dissolution by negotiating with the the various parties and independents until the 21st June deadline passes? Does the GG have the power to act unilaterally when a PM loses the confidence of the house and no only else holds it?
COMMENT: I have no idea what this 21 June deadline you refer to is. The Governor General does not dissolve the House except on advice from the Prime Minister. It is a requirement that the Appropriation bills be passed through the Senate before an election is called. There is no need to dissolve the House until 1 July when the half-Senate writs can be issued.
Except under the most extra-ordinary of circumstances, Governor-Generals do not negotiate with the parties to resolve deadlocks in the House of Representatives. It is the obligation of the House to sort out its problems.
The House cannot be dissolved until the Appropriation bills are passed, as without the Appropriation bills, government will not be permitted to spend one cent of expenditure after 30 June. That means pensions, defence, elections, everything.
This late in the term, the House doesn’t have to express confidence in anyone. If Gillard or Rudd lose a vote of no-confidence, they recommend an election. This late in the term of a Parliament, a loss of confidence leads to an election, not a change of government. The Opposition would offer the same advice as the government, call an election, so the Governor-General has no need to change her source of advice, so there is no requirement for the House to resolve confidence. It would be for the public to sort out the House deadlock via an election.
Posted by: Noel K | June 10, 2013 at 04:39 PM
Let me clarify. You wrote that writs must be issued within 10 days of the dissolution of the House. The 21st of June is 10 days before the 1st of July, the first date that writs can be issued for an election simultaneous with a half senate election. Therefore if the house is dissolved before 21st June, surely that means simultaneous elections are not possible due to the section 32 restrictions? Am I missing something?
COMMENT: Yes. The government can dissolve then House and issue writs for 3 August at once, and then issue the half-Senate writs on 1 July. The minimum campaign period is five weeks, hence the 3 August date, but the maximum is about nine so you could issue House writs now.
However, the House won’t be dissolved until all necessary legislation, including the budget, has passed the Parliament. The government would also be within its rights to request the House be prorogued pending the dissolution, but again you don’t do that until all required legislation has been dealt with. The Independents and opposition would be cranky at a prorogation, demanding the government move suspension in the House, but the government might find that criticism easier to deflect than cranky cross-benchers supporting opposition procedural motions in the House.
Posted by: Noel K | June 10, 2013 at 08:07 PM
Antony
I was curious whether there might be an emergency way to obtain supply in Australia. In 1896 an incoming federal government (in Canada) did not have enough supply for the whole fiscal year as the final appropriation acts had not been approved. The new government under Laurier decided to use an emergency provision in what is now called the Financial Administration Act that allowed for Special Warrants to be issued by the Governor General to appropriate funds. My understanding is that the provision was supposed to have been used for a one-off emergency like a critical railway bridge collapsing but it was surprisingly used for all supply needed for the government and has been used off and on since then for all government supply usually during or subsequent to an election.
COMMENT: I don’t think so, but previous elections have been deferred until the Parliament passes an interim supply bill. The appropriation bill has already been through the House, is due to go through the Senate in the next fortnight, so there is no need to create exotic financial instruments when normal funding is already in the parliament and ready to be passed before 30 June.
Posted by: David Gussow | June 10, 2013 at 11:19 PM
Hi Antony,
Isn’t it possible for the election to be held on 28 September without the house sitting on 20 August? (I’m thinking about how long Rudd could push the election out without facing the independents)
This is because the house could be dissolved more than six days (and up to ten) before the writs are issued on 19 August.
The election could also be later than 21 September and not require the house sitting after 20 August if the writs were issued earlier and the election campaign extended.
COMMENT: I can’t see why the government would put itself in caretaker mode any longer than it has to. There is also little suggestion that if Rudd becomes leader he would attempt too go longer than he has to before calling the election.
Posted by: Casey | June 11, 2013 at 01:06 AM