Saturday, July 21, 2018

''Next stop: Antarctica!'' -- It’s official: next January, in 2019, Elizabeth Rush will be sailing to Thwaites Glacier in Antarctica with the National Science Foundation ... ❄️❄️

Just how unstable is the massive Thwaites glacier? A major mission in 2019 is about to find out.

❄️🌫❄️''Next stop: Antarctica.'' -- It’s official: next January 2019 environmental essayist Elizabeth Rush will be sailing to Thwaites Glacier with the National Science Foundation ! ❄️🌫❄️

Elizabeth is the author of the book ''RISING,'' now published and available via Amazon order site. Expect this trip to be part of her next book, too!

discusses RISING, a "compelling piece of reporting, by turns bleak and beautiful" that shows "sea level rise is not some distant problem in a distant place . . . it’s affecting real people right now."

USA and UK sci­en­tific agen­cies have an­nounced their big­gest joint Ant­arc­tic re­search ef­fort in more than a gen­er­a­tion.
The fo­cus is the Th­waites Glacier, which is roughly the size of Flor­ida and sits on the west­ern edge of Ant­arc­tica. Sci­en­tists fear the ice body could flood the world’s coast­lines in our life­times.
“For global sea-level change in the next cen­tury, this Th­waites gla­cier is al­most the en­tire story,” said David Hol­land, a geo­sci­en­tist at New York Univer­sity, who will pair with Brit­ish Ant­arc­tic Sur­vey re­searcher Keith Nic­holls to lead one of the 6 sci­en­tific field mis­sions.
Ice melt­ing on Th­waites ac­counts for 4 per­cent of global sea level rise, an amount that’s nearly dou­bled since the 1990s. Sci­en­tists in the new five-year re­search col­lab­o­ra­tion hope to de­ter­mine how much more, and how fast, the gla­cier will melt as the world con­tin­ues to warm.
To­day, pro­jec­tions for sea level rise vary widely, from about a foot of sea level rise to six feet by cen­tury’s end. Some of that un­cer­tainty is tied to ques­tions re­gard­ing how Ant­arc­tica, and spe­cif­i­cally the West Ant­arc­tic Ice Sheet (home to Th­waites) will re­act to warmer air and wa­ter tem­per­a­tures.
Com­puter mod­el­ing shows Th­waites is un­sta­ble, and could start col­laps­ing within de­cades.
“Some ver­sions of that model give us very lit­tle change in the gla­cier … Equally rea­son­able-sound­ing ver­sions of that model will give us al­most com­plete col­lapse of the gla­cier, which would lead to .8 me­ters or 1 me­ter (2.6 to 3.2 feet) of sea level rise,” says Mr. Nic­holls, who is co-lead­ing a re­search proj­ect to study the ocean ice in­ter­face of the gla­cier.
Th­waites is los­ing ice rap­idly — its 50 bil­lion tons per year — as it sits perched in 2,600-foot-deep wa­ters atop a sea­floor “bump” that sci­en­tists fear is the last thing hold­ing it in place. Past the bump, the ocean gets deeper still, and if Th­waites re­treats down that hill, there could be no stop­ping it. Its con­tri­bu­tion to sea-level rise could in­crease dra­mat­i­cally, bump­ing up the cur­rent global rate of 3.2 mil­li­me­ters (about 0.12 inch) per year.
“The think­ing is that if it goes in­land, there are no bumps to hold it, and it will go faster and faster and re­treat ef­fec­tively to the South Pole,” Mr. Hol­land said.
“What we’re try­ing to do is work out which of those equally plau­si­ble ver­sions of the model is cor­rect,” Mr. Nic­holls added.
The UK Nat­u­ral En­vi­ron­ment Re­search Coun­cil and the US Na­tional Science Foun­da­tion is or­ga­niz­ing the ef­fort, which in­volves about 100 sci­en­tists from seven dif­fer­ent coun­tries and has been years in the mak­ing.
“Really the whole pro­gram is about un­der­stand­ing that ex­tra un­cer­tainty at­tached to sea level rise and do­ing what we can to re­move it, al­low­ing peo­ple to pro­tect their coastal en­vi­ron­ments and to pre­pare prop­erty to pro­tect their pop­u­la­tions,” said David Vaughan, di­rec­tor of Science at Brit­ish Ant­arc­tic Sur­vey, at a press con­fer­ence an­nounc­ing the re­search in Cam­bridge, En­gland, on Mon­day.
Remote area hard to study
The first sci­en­tist set foot on Th­waites back in the 1950s. The crit­i­cal re­gion where it is lo­cated will de­ter­mine how fast the gla­cier re­treats - the “ground­ing line” where ocean, ice and bed­rock meet at 2,600-foot depths - re­mains lit­tle stud­ied.
But only a few dozen re­search­ers have been back since the 1950s.
That’s partly be­cause Th­waites sits roughly 1,000 miles away from the near­est per­ma­nent re­search sta­tion, and the weather con­di­tions are par­tic­u­larly brac­ing.
“Lo­gis­tics make this sci­ence ex­tremely dif­fi­cult,” says Mr. Hol­land, who has pre­vi­ously worked on Th­waites. “The win­dow of op­por­tu­nity to do re­search is small, ba­si­cally Decem­ber to Jan­u­ary. Be­fore that it’s too cold, af­ter that it’s too cold.”
Eight teams in to­tal will re­search the gla­cier it­self, the Ant­arc­tic cli­mate sur­round­ing it, and the wa­ter un­der­neath it and at its edge. One team will sam­ple the bed­rock be­neath the ice sheet for clues as to whether the gla­cier has re­treated in the past, and if so, how it re­cov­ered. Radar and seis­mic anal­y­sis will ex­am­ine what con­trols Th­waites’ width and speed.
Another re­search proj­ect, co-led by Erin Pet­tit from the Univer­sity of Alaska Fair­banks, will look at how both the ocean be­low the gla­cier and the at­mo­sphere above it are af­fect­ing the ice.
Glaciers can de­sta­bi­lize when melt­wa­ter on the sur­face cause frac­tures that deepen over time. But they can also be eaten away by warm­ing ocean wa­ters cir­cu­lat­ing un­der­neath. Re­search­ers have re­cently dis­cov­ered that’s start­ing to hap­pen in Ant­arc­tica.
“[Th­waites], we think is be­ing af­fected more by what’s hap­pen­ing on the un­der­side, so the heat that’s be­ing brought in from the ocean, from the cir­cum­po­lar deep wa­ter,” Ms. Pet­tit said.
Ms. Pet­tit’s team will use hot-wa­ter drills to in­sert sen­sors into the gla­cier, and de­ploy un­manned subs — in­clud­ing the now-fa­mous Boaty McBoat­face — to mea­sure ocean tem­per­a­tures un­der­neath the gla­cier.
They’re even at­tach­ing sen­sors to seals ex­pand their view of con­di­tions in the Amund­sen Sea.
“[Seals] dive up and down and around, and they go all over the place, they ba­si­cally can pro­vide this spa­tial and tem­po­ral pic­ture of what the ocean prop­er­ties are,” Ms. Pet­tit said.
The lo­gis­tics of the re­search will be com­plex, even by Ant­arc­tic stan­dards. Some re­search­ers will fly from Brit­ish and Amer­i­can re­search bases. Once on site at their re­search lo­ca­tions, they’ll set up camp for weeks at a time in tents on the ice. Others will reach the gla­cier’s face on ice-break­ers.
The re­search ef­fort should give sci­en­tists in­sight into the fu­ture of not just Th­waites, but a larger piece of Ant­arc­tica.
“Th­waites is the 800-pound go­rilla, just be­cause of how big and wide and deep into West Ant­arc­tica this par­tic­u­lar out­let gla­cier goes,” says Chris Shu­man, a Univer­sity of Mary­land Bal­ti­more County pro­fes­sor work­ing at the NASA’s God­dard Space Flight Center and who is un­af­fil­i­ated with the proj­ect. “So un­der­stand­ing it will greatly im­prove our abil­ity to un­der­stand the re­sponse of the en­tire West Ant­arc­tic Ice Sheet.”
If the whole West Ant­arc­tic Ice Sheet were to col­lapse, that could raise sea lev­els by up to 13 feet.
The new re­search rep­resents a large in­vest­ment by US and UK po­lar re­search groups, and sig­nals how im­por­tant they be­lieve the fate of Th­waites will be to mil­lions of coastal res­i­dents of both coun­tries.
The Wash­ing­ton Post con­trib­uted.

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