07 Oct 2014:
Deep Oceans Not Warming As Previously Thought, Study Finds
The deepest reaches of earth's oceans have not warmed significantly over the last decade, according to scientists at NASA's Jet Propulsion Laboratory in California
— a finding that undermines a leading theory as to why the pace of global warming has slowed over the last 15 years. Scientists have speculated that the recent slowdown in rising surface air temperatures was a result of heat accumulating in the deep ocean. But in a paper
published in the journal Nature Climate Change
, the NASA researchers concluded that the vast majority of sea level rise since 2005 was attributable to just two sources: upper ocean heat expansion and glacial melting. From this they inferred that the deep ocean was not also warming. In a separate paper
published in the same journal, however, scientists from the Lawrence Livermore Laboratory noted that the upper ocean was absorbing between 24 and 58 percent more heat than was previously thought. That's not enough to account for the pause in surface air warming, but the researchers suggest
it is evidence that more accurate data on ocean warming is needed.
03 Oct 2014:
Thousands of Uncharted Ocean
Floor Features Revealed by Satellite Data
New maps of the seafloor created using satellite data reveal thousands of uncharted mountains and clues
about the formation of continents, researchers say. Among other findings, they identified a ridge in the Gulf of Mexico that had previously been associated with seafloor spreading, a major rift in the South Atlantic Ocean, and thousands of sea mountains — all of which had never before been documented. The maps are based on small ripples and dips in the surface of the ocean, which can be detected by satellites, the researchers explain in the journal Science
. Using these ocean surface variations, the scientists were able to infer the shape and contours of the new seafloor features. Previously, the only way to create detailed maps was to collect depth soundings from ships sailing directly over the seafloor, so only about 20 percent of the ocean floor had been accurately mapped, researchers say.
02 Oct 2014:
Large Sediment Plumes Flowing
From Greenland Glaciers, Images Show
Plumes of sediment-laden meltwater from southwest Greenland’s glaciers are easily recognizable in this
NASA satellite image
Sediment plumes off the coast of Greenland
captured in early September. Meltwater at the top of the ice sheet starts out relatively clean, but as it flows through glacial channels down to the ground and out into the ocean, it picks up large amounts of sediment — a byproduct of the glacier scraping the bedrock. As a result, plumes like the ones that appear light-blue in this photograph, are good markers for estimating the amount of meltwater leaving the ice sheet, researchers say. Melting from the Greenland Ice Sheet could result in global sea level rise of 2 to 8 inches, according to the most recent assessment from the Intergovernmental Panel on Climate Change.
01 Oct 2014:
Scientists Photograph Gathering
Of 35,000 Walruses on Alaskan Beach
In one of the largest gatherings of walruses documented in recent years, Alaska biologists photographed a
congress of roughly 35,000 animals resting on a beach
in northwestern Alaska. They swam to shore to rest, a walrus researcher explained, after the last remaining traces of sea ice melted in mid-September. Walruses typically rely on sea ice to provide a platform for resting and caring for their young as they swim to find clams, worms, and shrimp offshore, near the edge of the continental shelf. When no sea ice is available, as has been the case in the Chukchi Sea six of the last eight years, the walruses must make their way to shore. Besides taking them farther from their feeding grounds, the beach gatherings are dangerous for young walruses because they can be trampled, biologists say. The U.S. Fish and Wildlife Service is considering granting Endangered Species Act protections to Pacific walruses.
30 Sep 2014:
Half of the Planet's
Animals Lost Since 1970, Report Says
The number of animals on the planet has fallen 52 percent in the last 40 years, according to an analysis
Animal population trend since 1970
the conservation organization World Wildlife Fund (WWF). The group's Living Planet Index, which tracked the populations of more than 10,000 vertebrate species from 1970 to 2010, revealed major declines in key populations of mammals, birds, reptiles, amphibians, and fish. The situation is most dire in developing countries, the report said, where wildlife populations have fallen on average by 58 percent. Latin America saw the biggest declines, with more than 80 percent of the region's animals lost since 1970. Globally, freshwater populations have plummeted 76 percent. This year's numbers are worse than those calculated in the last report in 2012, which found declines of 30 percent since 1970. The organization attributed this to new statistical weighting, which it said better represents each region's biodiversity, though other researchers have been critical
of the new methodology. Habitat loss and degradation was cited as the primary cause of biodiversity loss.
Cashes Ledge: New England's
Rich Underwater Laboratory
A little over 70 miles off the coast of New England, an unusual undersea mountain range, known as Cashes Ledge, rises from the seabed. Regulators are contemplating lifting a 12-year-old ban on commercial groundfishing in some parts of this area, sparking a roiling debate. What's not in question, however, is that the highest peak in the range, Ammen Rock, teems with kelp forests, sea sponges, and a wide variety of fish and mollusks — much of it captured by ocean photographer Brian Skerry during dives made earlier this year.
View the gallery.
09 Sep 2014:
Ocean Acidification May Dull
Sharks' Ability to Smell Prey, Study Finds
Ocean acidification, which is driven by rising atmospheric carbon dioxide levels, may cause sharks to
Smooth dogfish shark laboratory testing
be less interested in hunting prey, according to
research published in Global Change Biology
. In laboratory experiments emulating CO2 concentrations as they are expected to be by the middle and end of this century, scientists from the U.S. and Australia found that the smooth dogfish shark became uninterested in squid odors — sometimes avoiding them altogether. Sharks in control waters pursued prey scents four times more often than sharks in waters with high CO2 levels, the study found. Rising ocean acidity can disrupt the proper firing of neurons, the scientists say, because it interferes with a specific receptor present in most marine organisms with a nervous system. A study earlier this year found that fish in waters with increased acidity were also less able to detect predator odors.
15 Aug 2014:
New Citizen Science Software
Aims to Document and Curb Illegal Fishing
Citizen scientists can now report — and potentially help stop — illegal fishing
with the snap of a photo thanks to
Illegal shark fin catch
a new smartphone app developed by the Nature Conservancy. The software, called ShipWatch
, was developed this summer during a "Fishackathon," a series of workshops hosted by the U.S. State Department to foster technology development and collaboration among computer programmers. ShipWatch allows users to upload photos of illegal fishing activities to a database, where they are labeled with date and location information and plotted on a central map. The developers hope the data will help authorities enforce existing fishing laws by, for example, developing flight maps for surveillance drones or strategically deploying enforcement authorities. "There are laws in place to say [the fishing] is illegal. The problem is they lack any kind of reporting mechanism," developers told Fast Co.Exist.
07 Aug 2014:
Mercury Pollution in Oceans
Has Tripled Since Industrial Revolution
Globally, oceans contain roughly 60,000 to 80,000 tons of mercury pollution, according to
a report published this week in Nature
detailing the first direct calculation
Ahi tuna has very high mercury concentrations.
of mercury pollution in the world's oceans. Ocean waters shallower than about 300 feet (100 meters) have tripled in mercury concentration since the Industrial Revolution, the study found, and mercury in the oceans as a whole has increased roughly 10 percent over pre-industrial times. North Atlantic waters showed the most obvious signs of mercury pollution, since surface waters there sink to form deeper water flows. In contrast, the tropical and Northeast Pacific were relatively unaffected. "We don't know what that means for fish and marine mammals, but likely that some fish contain at least three times more mercury than 150 years ago," and possibly more, the lead researcher said. "The next 50 years could very well add the same amount we've seen in the past 150."
23 Jul 2014:
Earth Observation Satellites Help
Scientists Understand Global Change
Global warming is affecting more than just atmospheric temperatures — it is also changing water cycles
, soil conditions, and animal migrations. Earth observation satellites aid scientists in measuring and monitoring these changes so societies can better adapt. Although there are well over 1,000 active orbiting satellites, less than 15 percent are used to monitor Earth’s environment. Yale Environment 360
presents a gallery of satellites that scientists are using to better understand how the planet is changing.
View the gallery.
08 Jul 2014:
Protection of Parrotfish
Could Slow Decline of Caribbean Reefs
The steady loss of coral reefs in the Caribbean could be partially reversed by taking a number of relatively simple steps, including stronger measures to protect the region’s parrotfish
, according to a new study. In a review of trends in Caribbean coral reefs
from 1970 to 2012, the Global Coral Reef Monitoring Network said that live coral only makes up about 17 percent of the region’s reef surfaces today. If present trends continue, the study said, coral reefs in the Caribbean will “virtually disappear within a few decades” because of foreign pathogens, algae invasions, pollution from tourism development, over-fishing, and warming waters. A key step in halting the decline is protecting parrotfish, which eat the algae that have been smothering coral reefs. The study said conservation measures, such as banning fish traps, have helped parrotfish populations rebound in some parts of the Caribbean, including Belize and the Bahamas.
Interview: Where Will the Earth
Head After Its ‘Climate Departure’?
The term “climate departure” has an odd ring, but its meaning is relatively straightforward. It marks the point at which the earth’s climate begins to cease resembling
what has come before and moves into a new state where the extreme becomes the norm. Camilo Mora — a University of Hawaii biogeographer, ecologist, and specialist in marshaling big data for climate modeling — has calculated a rough idea for the time of the earth’s climate departure: 2047. That date varies depending on region
, he says. But in a widely publicized paper published in the journal Nature
last year, Mora and 13 colleagues explored the concept of climate departure and what it will mean for our planet. In an interview with Yale Environment 360
, Mora explains why tropical regions will be most profoundly affected by climate change, why controlling population growth is at the core of the challenge posed by global warming, and the frustrations he and other scientists feel as their warnings about rising temperatures are ignored.
01 Jul 2014:
Small Island Nation of Kiribati
Purchases Foreign Land as Climate Refuge
The small island nation of Kiribati has purchased a swath of land in Fiji as a refuge for citizens who may be displaced by rising sea levels, marking the first time a
Kiribati's location (red) in the Pacific Ocean.
country has taken such actions as a defense against climate change, the Guardian reports
. Kiribati, home to 110,000 people scattered across 33 islands in the Pacific Ocean, is one of several small island nations in the Pacific and Indian oceans that could be extensively or completely submerged within a few decades. The cost of protecting such countries often far outweighs their national incomes. Kiribati, with a GDP of under $200 million, ranks among the 10 countries facing the most severe financial impacts of climate change. The tract of 20 square kilometers on the island of Vanua Levu, Fiji, could provide a future refuge for all of Kiribati's citizens, the nation's president said.
30 Jun 2014:
Antarctica's Emperor Penguins
To Be in Serious Decline By 2100, Study Says
Antarctica's Emperor penguins are facing dramatic declines by the end of the century and should be given endangered species status because of the threats posed
Sea ice loss threatens Emperor penguins.
by climate change, according to
an international group of scientists. If sea ice declines at the rates projected by current climate models, at least two-thirds of the colonies will likely shrink by more than 50 percent by 2100, the researchers report in Nature Climate Change
. That conclusion follows a 50-year study in eastern Antarctica of Emperor penguins, an iconic Antarctic species with 45 known colonies. Emperor penguins' survival is highly dependent on sea ice concentrations because they breed on the ice, and too little sea ice reduces the habitat for krill, a critical food source for the penguins. Granting the species protected status under the U.S. Endangered Species Act will provide tools for improving fishing practices of U.S. vessels in the Southern Ocean and potentially for reducing CO2 emissions in the U.S. under the Clear Air Act, the researchers say.
15 May 2014:
Intensity of Hurricanes
Now Peaking Farther From the Equator
Powerful, destructive tropical cyclones are now reaching their peak intensity farther from the equator and closer to the poles, according to a new study
in the journal
Hurricane Sandy's progression in 2012
. Over the last 30 years, tropical cyclones, also known as hurricanes or typhoons, have moved poleward at a rate of roughly 33 miles per decade in the Northern Hemisphere and 38 miles per decade in the Southern Hemisphere. Ocean temperatures between 82 and 86 degrees F seem to be "ideal for the genesis of tropical cyclones," said MIT scientist Kerry Emanuel, who co-authored the study, "and as that belt migrates poleward, which surely it must as the whole ocean warms, the tropical cyclone genesis regions might just move with it." The poleward shift of hurricanes and typhoons could lead to "potentially profound consequences to life and property" in regions that previously had not been hit by tropical cyclones.
14 May 2014:
Early El Niño Conditions
May Spell Big Weather Impact This Year
Indications are growing that an El Niño weather pattern may be forming in the Pacific Ocean, which could have a profound impact on global weather. El Niño events are spawned by unusually warm ocean waters in the Pacific,
and these NASA satellite images
are one indication of warmer waters. The images depict sea-surface height anomalies, with above average sea-surface height shown in various shades of brown. Above average sea-surface heights are an indication of warmer waters, which expand as temperatures rise. These two images compare conditions in 1997 — a year with one of the most powerful El Niño events of the 20th century — with conditions this May. If an El Niño pattern does develop this year, it could lead to wetter conditions in western North America and South America, which could help end a severe drought now plaguing the U.S. West. The 1997/98 El Niño also created warmer and drier conditions in much of Asia. Other evidence, including data from a network of buoys in the Pacific, also shows a deep pool of warm waters sliding east across the Pacific since January.
Interview: Can Marine Life Adapt
To the World’s Acidifying Oceans?
As the world’s oceans grow more acidic from increased absorption of atmospheric carbon dioxide, marine scientists are confronting a key question: How well can
organisms like mollusks, crustaceans, and corals adapt to these more corrosive conditions? One of the leading authorities in this field is University of California, Santa Barbara marine biologist Gretchen Hofmann. Her work in recent years has shown, in fact, that some sea organisms that build shells do seem to have some ability to acclimate to more acidic waters. But in an interview with Yale Environment 360
, Hofmann cautions that this adaptive capacity has its limits. The continuing burning of fossil fuels, she says, could push ocean acidity past a tipping point, rendering some mollusks and other organisms unable to build shells.
Read the interview.
09 May 2014:
Biodiversity, But Not Community
Composition, Surprisingly Stable Over Time
A major turnover of species in habitats around the globe is underway, resulting in the creation of novel biological communities, but overall species diversity is much more
stable than scientists had believed, according to a new report
in the journal Science
. In a survey of 100 long-term biodiversity monitoring projects in a variety of habitats around the world, the authors found that the majority of those studies (59 percent) documented increasing species richness. Biodiversity declined in 41 percent of the studies, but, in all cases the overall change in biodiversity was modest, the researchers said. When looking at changes in the species constituting those communities, however, the researchers found a surprisingly high rate of change — an average of about 10 percent change per decade. "A main policy application of this work is that we're going to need to focus as much on the identity of species as on the number of species," one of the study's authors said. "The number of species in a place may not be our best scorecard for environmental change."
08 May 2014:
Natural Variations May Account
For Up to Half of Greenland's Warming
Up to half of the recent climate change in Greenland and surrounding regions — which have warmed at roughly twice the pace of the rest of the planet since 1979 — may be due to natural climate variations that originate in the tropical Pacific and are not connected
Meltwater from Russell Glacier
with the overall warming of the Earth, a new study
says. Still, at least half the warming remains attributable to rising global carbon dioxide emissions, according to research published in the journal Nature
. Climate data and advanced computer models show that changes in the western tropical Pacific Ocean, which has been about 0.3 degrees warmer than normal, have caused shifts in atmospheric pressure over the North Atlantic. Those changes set off a stationary wave in the atmosphere that arcs in a great circle from the tropical Pacific toward Greenland, pulling warmer air over that massive island. "Along this wave train there are warm spots where the air has been pushed down, and cold spots where the air has been pulled up," one author explained. "And Greenland is in one of the warm spots."
05 May 2014:
New European Satellites
To Give More Detailed Views of Earth
The European Space Agency has begun launching
a series of satellites designed to collect detailed environmental data around the globe — from radar-based, high-definition imagery to information about the
atmosphere's chemical composition. The first satellite in the ESA's Copernicus program, the Sentinel 1A, was launched last month and has already returned many striking images based on radar data, such as this view of Brussels, Belgium, in which the dense urban area contrasts with the city's heavily vegetated surroundings. Once Sentinel satellite 1B is launched next year, the two will be able to map the entire globe in six days, giving researchers and conservationists a powerful way to monitor both short- and long-term changes in the environment. Four additional groups of satellites are set to launch this year. Those arrays will focus on high-resolution photo imagery, topography, surface temperatures, and atmospheric chemistry.
01 May 2014:
Extent of Marine Litter
Documented in Major Seafloor Survey
A major survey of the ocean floor has found trash piling up throughout the Atlantic and Arctic oceans and Mediterranean Sea, reaching depths of nearly 3 miles below the surface, according to scientists
Marine litter from study
European research organizations. Litter was located at each of the 600 sites surveyed, with plastic accounting for 41 percent and derelict fishing gear 34 percent. Glass, metal, wood, cardboard, clothing, pottery, and unidentified materials were also found. Garbage accumulated at sites as far as 2,000 kilometers (1,243 miles) from land and at depths up to 4.5 kilometers (2.8 miles), according to the report. Seafloor litter is a major problem since it can accumulate in and kill marine animals that mistake it for food. The trash can also entangle fish, seabirds, and coral. "This survey has shown that human litter is present in all marine habitats, from beaches to the most remote and deepest parts of the oceans," one author said. "These were [humans'] first visits to many of these sites, but we were shocked to find that our rubbish has got there before us."
11 Apr 2014:
Parasitic Flatworm Could Be
Major Threat to Coral Reefs, Scientists Say
A coral-eating flatworm with a unique camouflaging strategy could be a major threat to the world's coral reefs, according to
researchers in the U.K. The parasite, called Amakusaplana acroporae
, infects a type of staghorn coral known as acropora, a major component
Amakusaplana acroporae, a parasitic coral flatworm
of reefs, and can destroy its coral host very quickly. The parasite has been detected at the Great Barrier Reef, and because it has no known natural predators, researchers are concerned it could spread quickly and decimate reefs worldwide. A novel camouflaging strategy makes the flatworm difficult to detect and monitor, the researchers say. When eating the coral tissue, the worm also ingests the coral's symbiotic algae. Instead of digesting the algae completely, the worm keeps a fraction of them alive and distributes them, along with the fluorescent pigments that give coral its characteristic hue, throughout its gut so that it perfectly mimics the appearance of the coral. The parasite has been identified in numerous aquarium-based corals, and biologists worry that it could spread rapidly if aquarium-raised coral, fish, or seaweed are introduced to natural reef environments.
E360 Announces Contest
Yale Environment 360
For Best Environmental Videos
is holding a contest to honor the best environmental videos. Entries must be videos that focus on an environmental issue or theme, have not been widely viewed online, and are a maximum of 15 minutes in length. The first-place winner will receive $2,000, and two runners-up will each receive $500. The winning entries will be posted on Yale Environment 360
. The deadline for entries is June 6, 2014. Read further contest information.
28 Mar 2014:
West Antarctic Glacial Loss
Is Rapidly Intensifying, New Study Shows
Six massive glaciers in West Antarctica are dumping far more ice into the Southern Ocean than they were 40
An 18-mile crack in the Pine Island Glacier
years ago and now account for 10 percent of the world’s sea level rise
, according to a new study. Reporting in Geophysical Research Letters
, an international team of scientists said that the amount of ice draining from the six glaciers has increased by 77 percent since 1973. The scientists said that the ice loss from the six glaciers is so substantial that it equals the amount of ice draining annually from the entire Greenland Ice Sheet. The scientists used satellite data from 1973 and 2013 to gauge the ice loss from the six glaciers. The Pine Island Glacier
is moving more rapidly to the sea than any of the other six, with its speed increasing from 1.5 miles per year in 1973 to 2.5 miles per year in 2013. The glaciers are dumping more ice into the sea primarily because warmer ocean waters are loosening the ice sheets’ hold on the sea floor, which speeds up glacial flow.
17 Mar 2014:
Northeast Greenland Glaciers
Are Now Melting Rapidly, Study Finds
The glaciers of northeast Greenland, long thought to be the most stable part of the massive Greenland ice sheet, are melting at an accelerating pace, losing roughly 10
billion tons of ice annually for the past decade, say researchers
from the U.S. and Denmark. The finding will likely boost estimates of global sea level rise, which had previously not accounted for massive ice loss from that region, scientists say. The Zachariae ice stream in northeast Greenland, which drains 16 percent of the ice sheet, has retreated roughly 12.4 miles in the past decade, outpacing the fast-moving Jakobshavn glacier, which has retreated 21.7 miles over the last 150 years. Ice loss from the region is likely accelerating, the researchers say, because ice dams in nearby bays that had been blocking the glaciers' paths are now also melting, freeing the way for the glaciers to flow into the ocean.
06 Mar 2014:
Warm River Water Plays Major
Role in Arctic Sea Ice Melt, Study Finds
Relatively warm water flowing into the Arctic Ocean from rivers contributes significantly to Arctic sea ice melt each summer, a phenomenon that will intensify as the region warms, according to NASA researchers
. The river discharge not only melts coastal sea ice, it also has
a wider climate impact as it creates more open water, which is darker than ice and absorbs more heat from sunlight. As these NASA images show, when water from Canada's Mackenzie River flowed into the Beaufort Sea in the summer of 2012, average surface temperature of the open water rose by 6.5 degrees C (11.7 degrees F) after the pulse of river water. Flow from the Mackenzie raised sea surface temperatures as far as 350 kilometers (217 miles) from the coast. The researchers note that river discharge is becoming an increasingly important contributor to melting Arctic sea ice because the volume and temperature of fresh water discharge is increasing as inland Arctic areas warm more each summer.
05 Mar 2014:
Routes of Young Sea Turtles
Shed Light on Mystery of Turtles' Lost Years
By placing satellite tags on newborn sea turtles along the coast of Florida and tracking them in the western Atlantic Ocean, researchers have gained new insights
into the early migrations of threatened and endangered
turtles during their so-called "lost years" between hatching and returning to coastal waters as large juveniles. Rather than swimming in the currents of the North Atlantic gyre, as scientists had assumed, the young turtles actually leave the gyre and travel to the Sargasso Sea, which lies in the middle of the North Atlantic Ocean. While there, sensors on the turtles' shells registered more heat than the scientists expected, leading them to believe
that the young turtles swim near the surface of the Sargasso, basking in sunlight and feeding on a type of seaweed that grows in deep ocean waters. "From the time they leave our shores, we don't hear anything about them until they surface near the Canary Islands, which is like their primary school years," said an author of the study.
28 Feb 2014:
Seafaring Drones Could Reveal
Mysterious Lives of Sharks, Researchers Say
New automated watercraft
are helping scientists understand the secret lives of great white sharks, which gather in large numbers each winter in an area nicknamed the "White Shark Cafe." Although this stretch of ocean between Baja California and Hawaii
contains relatively few food sources, the sharks congregate and display strange behaviors, perhaps related to mating or feeding, one researcher explained to the San Francisco Chronicle
. Scientists haven't had a way to efficiently track and observe sharks in this environment, but new seafaring drone technologies might change that. For example, drones could follow migrations by homing in on acoustic tags on the sharks themselves. Marine biologists at Stanford
were recently able to track two great whites on their journeys from California to Hawaii and the White Shark Cafe, as the map shows, but current technology only allows scientists to recreate the sharks' journeys after monitoring tags pop off and are recovered. The new drones may prove useful not only for tracking sharks and other pelagic fish in real time, but also for collecting important ocean data such as temperature, acidity, and salinity, researchers said.
19 Feb 2014:
Loss of Arctic Sea Ice
Has Greater Warming Impact Than Expected
The steady disappearance of Arctic sea ice, which is causing the exposed and darker surface of the Arctic Ocean to absorb more sunlight, is having a more profound impact on global warming
estimated, according to a new study. The decline of albedo, or reflectivity, from the Arctic Ocean equals roughly 25 percent of the warming caused by rising carbon dioxide levels, according to scientists at the University of California, San Diego. The impact of this "albedo feedback," in which the highly reflective white surface of sea ice is replaced by heat-absorbing open ocean, is considerably stronger than climate models had predicted, according to the UCSD research
, published in the Proceedings of the National Academy of Sciences.
Researchers had thought increasing Arctic cloud cover might slow the albedo feedback, but this study indicates that is not happening.
03 Feb 2014:
Greenland's Jakobshavn Glacier
Is Moving at Record Speeds, Study Finds
Greenland's Jakobshavn Glacier is flowing into the ocean at a record pace of more than 17 kilometers per year, according to research
by U.S. and German scientists. The glacier, which drains 6 percent of the
massive Greenland ice sheet, moved at a rate of 46 meters per day in the summer of 2012 — four times the glacier's 1990s summer pace. The unprecedented speed appears to be the fastest ever recorded for any glacier or ice stream in Greenland or Antarctica, the researchers report in the journal The Cryosphere
. Scientists estimate the glacier added about 1 millimeter to global sea levels from 2000 to 2010; its faster flow into the ocean means Jakobshavn will add even more water over the current decade. Widely thought to be the source of the iceberg that sunk the Titanic
in 1912, the researchers say Jakobshavn is flowing at record speeds because its front edge, called the calving front, now overlies a particularly deep spot on the ocean floor. "As the glacier’s calving front retreats into deeper regions, it loses ... the ice in front that is holding back the flow, causing it to speed up," the lead researcher explained.