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By Matthew Green
OVER THE NORWEGIAN SEA, Norway, Sept 20(Reuters) - Bankinghard over the whitecaps off the west coast of Norway, thejetliner flying Dominika Pasternak and her fellow scientistsdescends so sharply that it seems for a moment as if the crew isabout to ditch them all in the drink.
But the pilot, an unflappable veteran of Britain's Royal AirForce, conveys a done-this-a-thousand-times confidence as theaircraft levels off at a nerve-shredding 50 feet above theNorwegian Sea.
"Three, two, one," he advises over the intercom. "Now!"
And so begins the work of this giant airborne laboratory – afour-engine, 112-seat passenger plane stripped out and refittedwith sensors that suck in air samples for analysis in real time.
Although they squint through the cabin windows as the planemakes its pass, Pasternak, 23, and her colleagues are chasing aquarry they will never actually see: methane, an invisible gasthat poses a growing risk to the Earth's climate.
When the United Nations hosts a summit in New York on Mondayto try to shore up the 2015 Paris Agreement to curb globalwarming, calls to cut emissions will focus on a more familiargreenhouse gas – the carbon dioxide produced by burning fossilfuels.
But methane, another carbon-based compound, is emerging as awild card in the climate-change equation. If CO2 has a warmingeffect akin to wrapping the planet in a sheet, theless-understood methane is more like a wool blanket.
Emitted from sources such as thawing permafrost, tropicalwetlands, livestock, landfills and the spidery exoskeleton ofoil and gas infrastructure girdling the planet, methane has beenresponsible for about a quarter of manmade global warming thusfar, some models calculate.
For more than a decade, scientists have been documenting amysterious rise in levels of methane in the atmosphere. And it'sgetting worse: Earlier this year, data from the U.S. NationalOceanic and Atmospheric Administration showed that the rate ofthe increase surged by 50% in the 2013-2018 period compared withthe preceding five years.
But the very urgency of the methane threat is also,paradoxically, what gives some scientists hope. Because methaneis acting like a foot on the accelerator for climate change,then rapidly reducing the amount leaking from oil and gasfacilities could, at least in theory, ease the pressure on theenvironment. That could buy time to confront the much biggerchallenge of cutting emissions of CO2.
In the United States, environmental groups have sought tobring methane emissions down by pushing the growing frackingindustry to take more stringent measures against leaks of thegas. But last month, the Trump administration proposed rollingback Obama-era regulations to curb methane emissions, saying themove would save companies money and remove red tape.
As the clock ticks, a network of researchers the world overis racing to find out why global methane levels are increasingso fast – and what can be done to stem the flow.
Here in the Arctic Circle, which is warming three timesfaster than the global average, Reuters accompanied three womenin their 20s as they hunted for clues. Working separately butwith the same goal, these researchers have staked their claim ona place where some of the most dramatic climate changes arestarkly visible, and the biggest dangers may await.
In their painstaking, sometimes solitary work, the youngscientists wrestle with the intellectual challenges posed by themethane riddle. But for all three women, their work in theArctic connects them to something deeper than science: a returnto childhood joys of the natural world, and a powerful sense ofpurpose.
Pasternak, wearing a white T-shirt bearing the words"Climate: The Fight of Our Lives" and a stylised image of theEarth engulfed in flames, is clear-eyed about the stakes.
"I think it's terrifying how much we are changing ourplanet, and how little is really done to counteract it," shesays. "We are guessing, but the more measurements we actuallyhave, the better we can understand what's going on."
THE HUNT BEGINS
As the jet races over the waves, Pasternak's gaze flickersbetween the cabin window and her laptop, which displays arolling graph of data recorded by the plane's instruments.
The clipped voice of the pilot, laconic as ever, cracklesover her headset, "I can see rigs on the left."
Pasternak, a Polish PhD student in atmospheric chemistry atBritain's University of York, focuses on the target: a clusterof oil rigs rising from the sea like fortresses, their squatlegs supporting imposing superstructures of derricks, helipadsand cranes.
Operated by the Natural Environment Research Council, aBritish government science funding agency, the flight is one ofa series of sorties that Pasternak and colleagues from severaluniversities conducted in late July and early August fromKiruna, an iron mining town in the Lapland region of northernSweden.
The plane moves in a deliberate path, passing back and forthat different altitudes to build up a profile of the atmospheredownwind of the rigs below. Securely strapped in against theG-force at low altitudes, Pasternak and the other researchersconfer over headsets and monitor the readings scrolling acrosstheir screens for any sign of a spike in methane levels. Theirconcentration is palpable, chatter kept to a minimum in therigours of low-level flight.
But after hours of methodically surveying the rigs, there isno sign of the kind of methane cloud they detected billowingfrom another platform the day before.
Frustratingly for Pasternak, the aircraft also narrowlymissed a giant supertanker, its bright red hull bulging withdomes used to store liquefied natural gas.
"They unfortunately got out of our range now, which is ashame," says Pasternak, who had hoped to take a methane readingnear the vessel. "They are hard to catch because they are veryspecialised ships."
For Pasternak, the flight is more than a research trip: It'sthe realisation of a childhood dream. Growing up on a hillsideoutside the city of Krakow, she would awake to see a layer ofpollution settled over the city like a shroud, then brave thesmog to go to school in the valley below. Escaping to thepristine Bieszczady Mountains for horse-riding summer camps orto the old-growth Bialowieza Forest, Pasternak promised herselfshe would find a way to protect the environment by pursuing acareer in science.
As the plane makes its way back to its temporary base in ahangar in Kiruna, she is sober about the uncertainties.
"Not many people paid attention to methane until quiterecently," she says. "We don't know enough about it to be ableto tell how dangerous it is, but we suspect it's verydangerous."
TIPPING POINT
Although the Italian inventor Alessandro Volta is betterknown for designing an electric battery, he is also credited asthe first scientist to identify methane, or CH4. Collecting gasseeping from the marshes on Lake Maggiore in 1776, he latershowed the gas could be ignited with a spark.
More recently, scientists have quantified methane's potencyas a greenhouse gas. Although it is much less prevalent in theatmosphere than CO2, the scientists found, it can generate morethan 80 times more warming – molecule for molecule – than CO2 inthe 20 years it takes to dissipate.
Today, there is broad agreement on the trend showing a surgein methane levels, but there is far less consensus on why it'shappening. Although oil and gas facilities are the leadingindustrial source of methane, scientists believe that growingamounts of the gas seeping from tropical wetlands in Africa andSouth America could be the biggest single driver of the currentmethane surge.
As the burning of fossil fuels pushes global temperatureshigher, methane-spewing microbes in fast-warming soils near theequator are going into overdrive, causing the wetlands to emitmore of the gas. These emissions in turn feed more warming, in avicious circle. Climate scientists call such loops "positivefeedbacks" – although their effects are anything but.
In the long term, the Arctic could be just as dangerous. Asthe permafrost thaws, dormant microbes find themselves immersedin the perfect warm, wet conditions to begin producing methanein climate-altering quantities, just like their tropicalcousins.
"The methane is then going to mix around the world multipletimes," says Ruth Varner, director of the Earth Systems ResearchCenter at the University of New Hampshire, who runs a long-termmethane study. "What happens in the Arctic doesn't stay in theArctic."
A LONELY VIGIL
In winter darkness, meters of snow cover Stordalen Mire, aspongy patch of Swedish peatland about an hour's drive fromKiruna Airport. The ice on a nearby lake is so thick you canconfidently scoot across it on a snowmobile.
But in summer, the snowpack recedes to slithers on distantpeaks, wispy heads of cottongrass peek through the soil, and thesun rarely sets. On such a day, Kathryn Bennett, 22, can befound pulling the oars of a rowboat.
On the shore, bogs lie in wait for anyone who strays toocasually from a precarious series of walkways made from planks.
"I have fallen in clear to the waist," says Bennett, apostgraduate student in earth sciences from Medway,Massachusetts, and a member of the methane research programme atthe University of New Hampshire. Although she laughs, herexpression suggests the dunking was amusing only in retrospect.
If Pasternak is serving in the air wing of the methane army,then Bennett is one of the grunts – picking her way across thebogland day after day and kneeling at the water's muddy edge,where tiny bubbles of methane burp periodically from a surfacewith a texture like used coffee grounds. Syringe in hand, sheextracts samples of gas accumulating in floating,foam-reinforced funnels, which she will later test to determinehow much methane they contain.
A few locals pass by in the distance picking cloudberries,and a dragonfly zips in jagged loops over the brackish water.Bennett keeps half an eye out for antlers, having been startledand delighted to see a couple of moose cooling off in the marshtwo days before.
"It’s so wild out here, you never know what you're going torun into," says Bennett, who traces her love for the outdoors toa childhood growing up camping and catching frogs.
Even to a first-time visitor, something about the landscapeat Stordalen doesn't look right. The walkways have subsided inplaces as the ground has given way, meaning Bennett's footfallssometimes splash in the stagnant water – which she says hascrept a little higher than during her fieldwork the previoussummer.
The slumping is a sign that the underlying layer ofpermafrost that once kept the ground rock solid has started tothaw. On drier patches of ground, long, narrow cracks haveappeared. In the marshland, new ponds have formed.
Researchers in other parts of the Arctic are witnessingsimilar changes. A team from the University of Alaska Fairbanksreported earlier this year how amazed they had been to findmillennia-old permafrost in Canada thawing 70 years earlier thanmodels had predicted, leaving depressions resembling those atStordalen.
"If this continues to happen, we can't turn it off," Bennettsays, her concern suddenly audible in her voice as she pauses byone of the bogs. "You can't just flip a switch and switch to anelectric car or solar panels. You can't just stop the permafrostfrom thawing, because it's already begun, which we see veryclearly in places like this.
"Then it becomes: 'Well, what can we do?' As scientists,what we can do is just try and understand this system and makebetter predictions about how it's going to change in thefuture."
Although she draws some comfort from the contribution she'smaking to understanding methane's role in climate change, she'salso keenly aware that even by flying to Sweden from the UnitedStates, she's adding to the emissions that cause it.
"Seeing really dramatic changes like this makes me think alot harder about the individual choices that I make and thinkabout how can we get other people to care," she says, nearingthe end of a nine-week stint in Lapland. "It hurts me to thinkthat I fly all the way over here to study this, but then it's soimportant to tell people this story, to understand, and tellpeople about what's happening here."
A CLIMATE "LEVER"
Climate scientists say the world must rapidly wean itselfoff its dependence on fossil fuels to stand a chance of avertingthe worst effects of rising temperatures. In the United States,oil companies argue that they can support a wider transition torenewable energy by providing natural gas from the frackingindustry as a "bridging" fuel. Gas has already displaced much ofthe country's coal-fired power generation, which produced moreCO2.
But studies suggest that about 2-3% of natural gas escapesas methane during production, storage and transport – exertingsignificant short-term warming.
Alex Turner studies methane as a postdoctoral fellow inatmospheric chemistry at the University of California, Berkeley.Because methane is such a fast-acting, relatively short-livedwarming agent, cutting leaks of the gas would have a quickimpact on the climate system, Turner argues. That might helpprevent runaway climate change from kicking in before the worldhas managed to control CO2 emissions – by far the biggest driverof long-term global warming.
"Of the greenhouse gases, methane is a really big lever onnear-term climate change," Turner says. "Large fractions ofemissions tend to come from a small number of sources, and ifyou can find those sources that emit a lot of methane, you mightbe able to make a huge dent in the total emissions."
In 2012, a network of governments, scientific institutes,businesses and civil society groups founded the Climate & CleanAir Coalition to curb emissions of powerful, short-livedpollutants such as methane. Since then, the U.N.-backed networkhas funded research around the world, including Pasternak'sflight this summer.
Some big oil companies say they're taking the problemseriously. Under pressure from activists and investors to showit is doing more to tackle emissions, British oil major BP Plcjust announced plans to use cameras, drones and robots to try todetect and prevent methane leaks at facilities around the world,for example.
"We are wanting to do continuous measurements and monitoringin all our future big projects," says Gordon Birrell, a chiefoperating officer at BP.
But some smaller drilling companies say they lack theresources that the majors can bring to bear on the methaneproblem.
"There are certainly countries and firms that are veryresistant, but the issue has started to gain real momentum,almost from a standing start just a few years ago," says DavidMcCabe, a senior scientist at the Clean Air Task Force, a U.S.advocacy group. "It's a case of trying to speed that up."
FIGHT FOR SURVIVAL
Clad in a khaki shirt and shorts like an old-schoolexplorer, Nina Lindstrom Friggens sets off through the dwarfwillow shrubs clinging to a lakeside near the northern Swedishvillage of Abisko. Her mission: to understand how the hiddenlives of trees will influence the future of the climate.
Kneeling at the base of a mountain birch, a stunted treeadapted to survive the Arctic's incessant cold and wind, sheflicks open a saw-toothed pocketknife and begins to dig.
Delicately, she lifts a lattice of roots between forefingerand thumb and uses the knife tip to point out minute whitesheaths that have formed over the finest filaments: fungi thatlive symbiotically with trees under the soil.
The 26-year-old Danish-British ecologist has always beenfascinated by Arctic landscapes, in part thanks to her childhoodlove of Philip Pullman novels set in frozen Norse fantasyworlds. Unlike Pasternak and Bennett, who are methane hunters tothe core, Lindstrom Friggens works on a broader carbon canvas,working to piece together the interplay between soil, ice andvegetation that will determine how quickly greenhouse gases seepfrom these northern lands.
The fungi she studies form a biological version of theinternet – what scientists have nicknamed a "wood-wide-web" –that allows trees to swap chemical signals and nutrients. As theArctic has warmed, it has also increasingly turned from white togreen, as saplings gain a foothold in the depressions left asthe permafrost thaws.
That's good news in terms of methane, because tree-coveredland is likely to emit less of the gas, says Lindstrom Friggens,a PhD student in plant-soil ecology at Scotland's University ofStirling. But there's a big catch: The expanding root networkshelp to rapidly decompose ancient subsoil stores of carbon intovast quantities of CO2, setting new feedback loops in train.
How quickly thawing permafrost could push the Arctic'sproduction of methane into overdrive is still a subject ofspeculation. But the impact of warming on the region was madevividly clear earlier this month, when scientists jolted Swedesby announcing that the south peak of Kebnekaise, the largemountain not far from where Lindstrom Friggens was conductingher research, had been dethroned as the country's highest peak.
The glacier on the summit, which generations of Swedishschoolchildren have considered a permanent, majestic fixture ofScandinavia's natural heritage, melted so much that it is nowlower than the mountain's ice-free northern peak.Reflecting on the prospect of far greater climate impacts,Lindstrom Friggens finds solace in nature's ability to endure.
"I quite like that it's bleak and it's rough; there's abeauty in that somewhere – that struggle to survive in anenvironment which is throwing everything at you all the time,"she says.
A seagull glides low over the lake, and the immenselandscape of water, sky and rock feels almost unfathomably old.A raw life force seems to hum inaudibly in the Arctic silence asLindstrom Friggens reaches a path leading back to the researchstation that is her temporary home, where she will watch theendless summer days start to shorten.
"There's so much life, yet it's so harsh to survive here,"she says. "But it perseveres."
(Reporting by Matthew Green; edited by Kari Howard)
