'Dangerous' Antarctic glacier has a hole roughly two-thirds
area of Manhattan, scientists warn
Brett Molina USA
TODAY
Published 12:39 PM EST Jan 31, 2019
A large cavity has formed under what has been described as
one of the world's most dangerous glaciers, and could contribute to a
significant bump in global sea levels, said NASA scientists.
A study led by the agency revealed a cavity about two-thirds
the area of Manhattan and roughly 1,000 feet tall is growing under Thwaites
Glacier in West Antarctica.
The cavity is large enough to have contained 14 billion tons
of ice, most of which has melted within the last three years, say researchers.
"(The size of) a cavity under a glacier plays an
important role in melting," said lead author Pietro Milillo of NASA's Jet
Propulsion Laboratory in a statement. "As more heat and water get under
the glacier, it melts faster."
The study was published Wednesday in the peer-reviewed
journal Science Advances.
Thwaites has been described as one of the world's most
dangerous glaciers because its demise could lead to rapid changes in global sea
levels. JPL said the glacier, about the size of Florida, holds enough ice to
raise ocean levels another two feet if it completely melts. It also backstops
other glaciers capable to raising sea levels another eight feet.
Researchers discovered the cavity using ice-penetrating
radar in NASA's Operation IceBridge, an airborne survey launched in 2010 to
study polar ice.
Last year, the National Science Foundation and Britain's
Natural Environment Research Council launched a joint program called the
International Thwaites Glacier Collaboration to study the unstable glacier and
its role in sea levels.
More: Here are the facts: Despite winter storms, global
warming is real
Is deep freeze the latest sign climate change is
accelerating?
Extremes consistent with theories about how emissions could
affect weather patterns
Jonathan Watts
Sat 2 Feb 2019 06.00 GMT
Hundreds of thousands of fish have choked during Australia’s
hottest month since records began, swathes of the United States is colder than
the north pole, new ruptures have been found in one of the Antarctic’s biggest
glaciers and there are growing signs the Arctic is warming so fast that it
could soon be just another stretch of the Atlantic.
And so the new year is carrying on where the old one left
off, with growing signs climate disruption is accelerating at a more
destructive rate than many scientists predicted.
The US deep freeze, which has plunged temperatures in
Minnesotato -50C (-58F), may appear to have little in common with the searing
heatwave that cooked Marble Bar, Australia, in 49.1C. But the extremes are
consistent with theories about how increasing human emissions change major
weather systems.
As carbon builds in the atmosphere, the planet warms and the
ice caps melt, so the temperature gradient between the equator and the poles
flattens out. Although the science is not yet conclusive, many scientists
believe this is weakening the jet streams, which are important drivers of
weather systems.
During the summer, this means high-pressure fronts linger
for longer causing heatwaves such as those in parts of the northern hemisphere
last May, June and July, and in the southern hemisphere over the past two
months. During the northern winter, it loosens the polar vortex, which lets the
warmer southern air in, causing the freakishly high Arctic temperatures
recorded last winter, and allows the frozen air out, which is being seen in the
US. This also manifested itself last year in Europe as “the Beast from the
East”.
Despite seasonal ups and downs, the overwhelming global
trend is towards higher temperatures. Last month, the Copernicus Climate Change
Service, the European institute that gathers satellite data, was the latest
institution to confirm the past four years have been the warmest recorded.
“Dramatic climatic events like the warm and dry summer in large parts of Europe
or the increasing temperature around the Arctic regions are alarming signs to
all of us,” said Jean-Noël Thépaut, the head of Copernicus Climate Change
Service. “Only by combining our efforts, can we make a difference and preserve
our planet for future generations.”
In October, the United Nation’s top climate science body –
the Intergovernmental Panel on Climate Change – warned that North America and
Australia were among the areas likely to feel the impact of significant rises
in extreme heat.
Bob Ward of the Grantham Research Institute on Climate
Change and the Environment, said: “It is very important to note that, despite
the cold weather, there is a very clear trend in the United States and Canada
of winters becoming warmer, as they are around the world. It is a reminder that
part of the challenge of climate change is that many of the impacts may be
unexpected and unprecedented.
“Carbon dioxide levels in the atmosphere are now higher than
they have been on Earth for millions of years. Modern humans have only been
around for about 200,000 years, so we have no historical or even evolutionary
experience of the climate that we are creating.”
“That is why nobody can claim with confidence that we will
be able to cope with all the impacts that everyone can see are developing
around the world, including more extreme droughts, heavy rainfall, and
heatwaves, disappearing glaciers and ice caps, rising sea levels and acidifying
oceans.”
THE RACE TO UNDERSTAND ANTARCTICA’S MOST TERRIFYING GLACIER
SCIENCE SEASON IN Antarctica begins in November, when
noontime temperatures at McMurdo Station climb to a balmy 18 degrees Fahrenheit
and the sun hangs in the sky all day and night. For a researcher traveling
there from the United States, the route takes time as well as patience. The
easiest way is to fly from Los Angeles to Christchurch, New Zealand—a journey
of 17 hours, if you’re lucky—and then to McMurdo, a charmless cluster of
buildings that houses most of the southern continent’s thousand or so seasonal
residents and both of its ATMs. McMurdo isn’t the end of the line, though.
Often it’s just a pass-through for scientists hopping small planes to penguin
colonies or meteorological observatories farther afield.
Few places in Antarctica are more difficult to reach than
Thwaites Glacier, a Florida-sized hunk of frozen water that meets the Amundsen
Sea about 800 miles west of McMurdo. Until a decade ago, barely any scientists
had ever set foot there, and the glacier’s remoteness, along with its
reputation for bad weather, ensured that it remained poorly understood. Yet
within the small community of people who study ice for a living, Thwaites has
long been the subject of dark speculation. If this mysterious glacier were to
“go bad”—glaciologist-speak for the process by which a glacier breaks down
into icebergs and eventually collapses into the ocean—it might be more than a
scientific curiosity. Indeed, it might be the kind of event that changes the
course of civilization.
In December 2008, a Penn State scientist named Sridhar
Anandakrishnan and five of his colleagues made the epic journey to Thwaites,
two days from McMurdo by plane, tractor, and snowmobile. All glaciers flow, but
satellites and airborne radar missions had revealed that something worrisome
was happening on Thwaites: The glacier was destabilizing, dumping ever more ice
into the sea. On color-coded maps of the region, its flow rate went from stable
blue to raise-the-alarms red. As Anandakrishnan puts it, “Thwaites started to
pop.”
The change wasn’t necessarily cause for alarm. Big glaciers
can speed up or slow down for reasons that scientists still don’t completely
grasp. But Anandakrishnan knew that Thwaites’ unusual characteristics—it is
shaped like a wedge, with the thin front end facing the ocean—left it
vulnerable to losing vast quantities of ice quickly. What’s more, its size was
something to reckon with. Many glaciers resemble narrow rivers that thread
through mountain valleys and move small icebergs leisurely into the sea, like a
chute or slide. Thwaites, if it went bad, would behave nothing like that.
“Thwaites is a terrifying glacier,” Anandakrishnan says simply. Its front end
measures about 100 miles across, and its glacial basin—the thick part of the wedge,
extending deep into the West Antarctic interior—runs anywhere from 3,000 to
more than 4,000 feet deep. A few years before Anandakrishnan’s first
expedition, scientists had begun asking whether warming waters at the front
edge could be playing a part in the glacier’s sudden stirring. But he wanted to
know what was going on deep below Thwaites, where its ice met the earth.
If the mysterious Thwaites Glacier were to “go bad,” it
might change the course of civilization.
During that 2008 expedition and another a year later,
Anandakrishnan’s team performed the geologic equivalent of an ultrasound on
Thwaites. Each morning they’d wake up in their freezing tents, call McMurdo on
the satellite phone to attest that they were still alive, eat a quick breakfast,
and move out by snowmobile across the blankness of the ice sheet. At a
prearranged point, they’d place an explosive charge at the bottom of a
hole—usually between 70 and 100 feet deep—fill the hole with snow, and blow it
up. The wave of energy would travel from the charge to the bed of the glacier
and back to the surface, where it would be recorded by an array of geophones,
exquisitely sensitive seismic instruments. By measuring the time it took for
the waves to rebound, and by looking at alterations in the waves’
characteristics, Anandakrishnan’s team could gain clues about the depth and
makeup of the glacier’s bed, thousands of feet below. They repeated the process
again and again.
By the end of the mission in 2009, Anandakrishnan and his
colleagues had collected data from about 150 boreholes. The new information
didn’t precisely explain what was hastening Thwaites’ acceleration, but it was
a start. Meanwhile, the satellite maps kept getting redder and redder. In 2014,
Eric Rignot, a glaciologist at NASA, concluded that Thwaites was entering a
state of “unstoppable” collapse. Even worse, scientists were starting to think
that its demise could trigger a larger catastrophe in West Antarctica, the way
a rotting support beam might lead to the toppling not only of a wall but of an
entire house. Already, Thwaites’ losses were responsible for about 4 percent of
global sea-level rise every year. When the entire glacier went, the seas would
likely rise by a few feet; when the glaciers around it did, too, the seas might
rise by more than a dozen feet. And when that happened, well, goodbye, Miami;
goodbye, Boston.
No one could say exactly when Thwaites would go bad. But
Anandakrishnan and his colleagues now had an even keener sense of the perils
that the glacier posed. “We had been walking on the lip of a volcano without
knowing it,” he says.
Sridhar Anandakrishnan has been to Antarctica more than 20
times. ROSS MANTLE
ON A WARM afternoon this past September, at a conference at
Columbia University’s Lamont-Doherty Earth Observatory, just up the Hudson
River from Manhattan, Anandakrishnan gave a lecture detailing his plans for
returning to Thwaites. All told, there were 120 scientists in attendance, some
of whom had been meeting annually to discuss the West Antarctic Ice Sheet. For
25 years, they had debated whether the region’s potential instabilities were
cause for alarm and whether Thwaites, which acts as the keystone holding the
ice sheet together, was a near-term risk. This year the conference had a larger
sense of purpose: The United States and Great Britain had recently announced a
more than $50 million joint venture known as the International Thwaites Glacier
Collaboration. Over the course of five years, scientists would probe the
glacier in every conceivable manner.
At the conference, it was hard to shake the notion that the
situation was urgent. “The question is, what’s going to happen next?” Ted
Scambos, the American project coordinator of the Thwaites Collaboration, told
me. “Is it going to be 50 years or 200 years before we see a truly large
increase in the rate of ice being unloaded into the ocean from that glacier?”
As a practical consideration, the world needed to know. Over the past few
decades, climatologists have become better and better at modeling how Earth’s
atmosphere is responding to rising concentrations of greenhouse gases. But
ice-sheet models, which aim to translate various future scenarios into actual
impacts, such as changes in sea level, aren’t nearly as reliable. One reason
for this is that the physics of glaciers has proven formidably complex, with
many factors that influence their behavior still unknown. “There is uncertainty
and crudity in these models,” Dave Pollard, an ice-sheet expert from Penn
State, told me. The point of the Thwaites Collaboration, he said, is to fill in
some of the blanks.
The architects of the collaboration, the National Science
Foundation in the US and the Natural Environment Research Council in the UK,
selected eight research projects from among 24 proposals. Some will focus on
the front end of Thwaites, which extends beyond the shoreline of Antarctica and
forms a cantilevered ice shelf that floats on the Amundsen Sea. Ice shelves are
a good thing. As glaciologists are fond of saying, they act like corks,
preventing upstream ice—the wine in the bottle, so to speak—from pouring into
the sea. They also protect the glacier from warming waters. Thwaites’ ice shelf
has been crumbling, so one group in the collaboration, calling itself Tarsan
(Thwaites-Amundsen Regional Survey and Network), will investigate the local
effects of ocean circulation and warm air. Another team, known as Melt (not an
acronym), will use submersible robots and seals tagged with satellite
transmitters to examine the glacier’s so-called grounding line, the point where
its front end rests on the ocean floor.
Anandakrishnan’s seismic experiments will be among the most
crucial parts of the collaboration’s work. His group has taken the name Ghost,
which stands for Geophysical Habitat of Subglacial Thwaites. His study will map
a sliver of the bed beneath the glacier, deep below sea level, in an effort to
predict how Thwaites will behave in the future. Soft, wet sediment,
Anandakrishnan says, can make a glacier slide extremely fast, and it is
probable that a lot of such sediment lies under Thwaites. He likens it to what
you might find “when you go into your backyard and play with the mud with your
kids. It’s got a little bit of strength but not a great deal.”
A few weeks before the conference, I visited Anandakrishnan
at Penn State. His office, an austere space with white cinder block walls,
cluttered with books and stacks of papers, had little in the way of mementos to
show that he’s been to Antarctica more than 20 times. As we talked, he laid out
his plan for studying Thwaites. In 2008 and 2009, he told me, he examined an
area of the glacier bed roughly 25 miles long. The blueprint for the next four
years, beginning in the winters of 2020 and 2021, is far more ambitious: With
nearly a ton of explosives in tow, Anandakrishnan and around a dozen colleagues
should be able to chart an area 10 times as big. If things go right, the
seismic reverberations will illuminate the contours and material composition of
what’s underneath Thwaites.
Anandakrishnan stood up and walked over to a whiteboard to
draw me a picture of the glacier bed’s geometry. It was a line that began with
a bump in the front, where the glacier met the sea, and sloped gently downward
as it went inland. At the moment, he said, it’s unclear how long Thwaites has
before it pulls off its bump—its grounding line—and starts a rapid decline.
“It’s kind of hanging on by its fingernails right about there,” he explained,
gesturing at the bump.
Glaciers like Thwaites that terminate in the ocean tend to
follow a familiar pattern of collapse. At first, water gnaws at the ice shelf
from below, causing it to weaken and thin. Rather than sitting securely on the
seafloor, it begins to float, like a beached ship lifted off the sand. This exposes
even more of its underside to the water, and the weakening and thinning
continue. The shelf, now too fragile to support its own weight, starts snapping
off into the sea in enormous chunks. More ice flows down from the glacier’s
interior, replenishing what has been lost, and the whole cycle starts over
again: melt, thin, break, retreat; melt, thin, break, retreat.
It is difficult to find any scientist, Anandakrishnan
especially, who thinks that Thwaites can avoid this fate. Because its bed lies
below sea level, water will pursue it far inland. When Thwaites’ grounding line
starts to retreat, possibly within the next few decades, Anandakrishnan says,
it could do so fairly fast. That retreat may raise sea levels only modestly at
first. From radar studies, scientists believe they have detected another bump,
now called the Ghost Ridge, that runs about 45 miles behind the existing one.
This is what Anandakrishnan’s Ghost team will trace with their seismic
experiments from the surface. Is the ridge made of wet sediment, or is it firm
and dry? Is it low, or is it high? Such esoteric differences may have
extraordinary effects. If any good news arises from his fieldwork at Thwaites,
Anandakrishnan says, it may come from the discovery that the glacier has a
chance of getting firmly stuck on the Ghost Ridge.
You might therefore think of Thwaites as a man dangling from
the edge of a cliff. Just as he falls, he grips a rock, a sturdy handhold, to
avoid the abyss. Of course, the rock may loosen and dislodge tragically in his
hands. And then he’ll drop.
1/5ANATOMY OF A MELTDOWN: In one of the largest scientific
collaborations in Antarctic history, a team of British and American researchers
is scrutinizing Thwaites Glacier from every side—air, ice, and sea.Bryan
Christie Design
2/5Grounding Line: For the time being, Thwaites is held in
place by a bump in the seafloor. Once it pulls off this so-called grounding
line, it’ll begin to collapse more quickly.Bryan Christie Design
1/5ANATOMY OF A MELTDOWN: In one of the largest scientific
collaborations in Antarctic history, a team of British and American researchers
is scrutinizing Thwaites Glacier from every side—air, ice, and sea.Bryan
Christie Design
THE FIRST TEAM ever to set foot on Thwaites Glacier, in the
late 1950s, included a crusty glaciologist named Charlie Bentley. He spent 25
months driving around West Antarctica in a tractor, taking soundings across the
ice. His process was much like Anandakrishnan’s. Bentley would drill a hole
deep enough to reach the compact layer of snow known as firn or, better yet,
solid ice; place in it an explosive charge; and then register the shock wave
using geophones. In those days, the data was recorded in analog form, with a
needle “that would shake back and forth and inscribe something on a piece of
paper that was whipping past,” Anandakrishnan says. “Afterwards, you would look
at the record, and the distance on the paper was equivalent to a certain amount
of time.” Bentley’s momentous discovery was that much of West Antarctica’s land
is actually below sea level, even though it is cloaked by thick sheets of ice.
Anandakrishnan never intended to help revolutionize this
process with digital networks, but that’s how things turned out. He had little
interest in ice or climate when he arrived as a graduate student in electrical
engineering at the University of Wisconsin in the mid-1980s. Born in India, he
had spent his teenage years in suburban Maryland, which is why he carries in
his speech a relaxed folksiness; his father, a civil engineer, worked as a
science adviser to the Indian ambassador in Washington. Anandakrishnan’s main
interests during his college years were fiber optics and lasers. He planned to
become a professor or an optical engineer in Silicon Valley. But then he
answered an advertisement for a summer job.
A group of Wisconsin glaciologists were trying to link their
instruments together in the field, so they could record their data on a central
hard drive. Anandakrishnan designed a fiber-optic system for their project and
was eventually asked to go to Antarctica to install it. He was 23 years old.
“These were things that I knew absolutely nothing about,” he says. “I’d come
from a straight engineering background. I knew that glaciers existed. I knew
glaciers had something to do with sea level. But I really knew nothing more
than that.” When he got back to school, he remembers thinking, “I’m a year into
my PhD program in electrical engineering. I have a guaranteed mansion or a
yacht down the road, if I want it, or a position in a university. Or I could
retrain myself—learn seismology, geology, glaciology, climate, oceans.” He’d
been transfixed, he says, by the “unending horizons” of the ice sheet, but he
was also taken in by a world of what he calls “capital-T” toys—snowmobiles,
forklifts, cranes, and cargo planes. He immediately signed up for a PhD in
glaciology, which happened to be Bentley’s department.
Anandakrishnan knows that exploding small bombs in ice may
seem primitive. Each blast, known as a shot, can yield a foul gas that blows up
from the borehole, along with sooty residue that sometimes rains down on
researchers and their equipment. “But the reality is there is almost no other
way to get the information we’re trying to get,” he says. Airborne radar
missions can do some of the same work with equal accuracy and less fuss, but
they can’t penetrate rock, so they don’t reveal much about the nature of the
glacier bed.
This used to be the case with seismic soundings too. When
Bentley was driving around Thwaites in 1957, the only thing he could calculate with
any certainty was depth. When digital recordings became standard in the 1980s,
researchers could focus on small changes in the reflection strength of the bed
at different points and different angles. This new level of sensitivity,
Anandakrishnan says, profoundly changed his field.
Innovations in explosives have also helped. Early glacier
soundings, including Bentley’s, were done with TNT. On the upcoming Thwaites
expeditions, Anandakrishnan—who still designs much of his own equipment—will
instead use PETN, a chemical compound frequently found in plastic explosives.
(It comes in 200-gram cylinders about the size of your index finger.) Besides
being very stable, PETN is fast; its seismic waves propagate through ice at
about 12,000 feet per second. This is critical, because a higher-frequency
explosion will collect more detailed information about the glacier bed.
When it comes time for a shot on Thwaites, the wind has to
be quiet. Nobody is allowed to breathe, cough, or sneeze. “We have a protocol
for all machinery in the area to be shut off,” Anandakrishnan says. “Nothing
can be happening. People can’t be walking. They can’t be talking. Everybody
gets stock still. And for that five seconds when that seismic energy is coming
up to your geophones, that’s the only thing you want those devices to be
hearing.” On the surface you hear a thunk. If you’re close enough, and if it’s
a large enough shot, you can feel it in your feet, a little tap on the soles.
The team will look at the data quickly to confirm that the blast reached the
bed. Then they’ll move on.
I asked Anandakrishnan whether there was any chance that he
might crack off part of Thwaites with his explosive charges, which can
sometimes add up to about a kilogram. I imagined some kind of calamitous
avalanche, as in the Alps. He shook his head. “This ice sheet is so large,” he
said. His small bombs would destroy the office we were sitting in, but they
were nothing compared with the forces of nature moving Thwaites’ ice into the
ocean.
PERHAPS THE GREATEST problem in imagining the future of
Thwaites lies in trying to imagine a natural disaster that has never occurred
in all of recorded human history. One day at Penn State, I dropped in on
Anandakrishnan’s colleague Richard Alley, who sat me down in his office and
insisted that I watch a clip of a short documentary he had been replaying on
YouTube. Like his friend Anandakrishnan, Alley studied with Charlie Bentley at
Wisconsin and has been thinking about the instabilities of West Antarctica for
30 years. The video detailed a catastrophe in Norway in the late 1970s. In the
agricultural town of Rissa, the land, an unstable soil known as quick clay,
suddenly liquefied during a construction project. Within a few hours, 82 acres
fell into a lake. One person died, and the man filming the incident barely
escaped with his life.
“It’s not ice,” Alley cautioned me as we watched. “But it’s
an analogy for what can happen when things can break, when the cliff is too
high and nothing piles up at the bottom.” Alley’s point was that this could be
the situation for Thwaites. As a glacier breaks down, larger cross sections of
the wedge become exposed to the elements. The process creates an ice cliff,
which gets so tall that it can no longer sustain itself. In engineering terms,
the ice suffers a material failure. In models, it breaks, and it breaks fast.
The resulting icebergs are likely to float away, carried by swells and tides, rather
than create a pileup that slows things down.
“So the question,”
Alley said, “is where is the threshold for triggering that in an irreversible
or nearly irreversible way?” In his view, one of the most critical pieces of
the Thwaites Collaboration is investigating when the glacier’s grounding line
might move beyond the Ghost Ridge. This is conceivably the point at which
disaster ensues. “If Thwaites behaves itself, and we only get a meter of
sea-level rise by 2100 under a high-emissions scenario, a meter is a big deal,”
Alley said. It would be painful, but humanity could adapt by building
floodgates and sea walls, rethinking patterns of real estate development, and
retreating from vulnerable shorelines. But what Thwaites and the glaciers
around it have in store could be much more significant. “You have to think in
terms of maybe 3 feet, but maybe 10 or 15,” Alley said. Maybe 15 feet. In that
scenario, the Jefferson Memorial and Fenway Park would be underwater, and the
Googleplex would become an archipelago. Outside the US, the damage would be
incalculable. Shanghai, Lagos, Mumbai, Jakarta—all would flood or drown.
For now, the prospect of Thwaites’ rapid collapse seems
enough of a possibility that a few scientists have suggested buttressing it.
One of these geoengineering schemes, recently put forward by Michael Wolovick
and John Moore, proposes that an “artificial sill” of gravel and rocks be
constructed at the base of Thwaites to protect it from warm water. In an
academic paper, Wolovick and Moore acknowledge that such an undertaking would
be “comparable to the largest civil engineering projects that humanity has ever
attempted.” When I spoke with Wolovick, he told me that the idea was intended
to spark debate about a “glacial intervention” that may take a century to
conceive and execute. Whatever the cost, he said, it seemed worth it. Rapid
sea-level rise could mean trillions of dollars in losses and the mass migration
of hundreds of millions of people. The poorer parts of the planet would
invariably suffer worst. “If you stop sea-level rise at the source,” Wolovick
said, “that benefits everyone.”
If the worst happened, the Jefferson Memorial would be
underwater. Shanghai, Lagos, Mumbai—all would flood or drown.
When I asked Anandakrishnan what he thought of this plan, he
said it made him wonder whether we were in danger of losing sight of the larger
problem. Geoengineering Thwaites would be the most difficult and dangerous
construction project in the history of humanity, he agreed. As one of only two
dozen people who has actually been to the glacier, he could say this with some
authority. About 100 workers died building the Hoover Dam, he noted; the
hazards here might be similarly large, or worse, even if you could get the
right equipment in place. “But whether geoengineering works or not—and that’s a
separate question—it doesn’t address the effects of pumping CO2 into the
atmosphere,” he told me. “And that’s what is raising temperatures, melting
glaciers, acidifying the ocean, and changing weather patterns around the
earth.”
Dave Pollard, the Penn State ice-sheet modeler, and his
colleague Rob DeConto, of the University of Massachusetts, have found divergent
futures for Thwaites. “It ranges from devastating sea-level rise and rapid
retreat into the middle of West Antarctica for ‘business-as-usual’ emissions,”
Pollard told me, to “very little sea-level rise and tiny retreat around the
edges.” The second future is possible, though, only if we keep atmospheric
carbon dioxide concentrations where they are today or allow them to go only
slightly higher. Such a feat would involve cutting back drastically on fossil
fuels and making a wholesale switch—as soon as possible—to a renewable-energy
economy. Pollard’s point was that even a glacier as vulnerable as Thwaites
could conceivably be contained if humans decided to radically change their
behavior.
And that’s the biggest problem of all. We’re so small and so
stubborn, and the challenges in holding back the ice are so large. Saving
Thwaites, or even finding out whether the Ghost Ridge looks stable, won’t save
the world. At the rate temperatures are rising, Anandakrishnan may soon have to
pack up his explosives and go elsewhere. By then, some other glacier will be
hanging by its fingernails.
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