06 May 2014:
Darwin's Finches Fight Off
Parasitic Maggots with Treated Nest Fibers
Researchers apparently have discovered a unique way to help Darwin's finches on the Galápagos Islands fight off the parasitic maggots
threatening their survival, according to a new report
in the journal Current Biology
. While working in the Galápagos, scientists
A Darwin's finch collects treated cotton for its nest
from the University of Utah noticed that the finches often collected cotton and other fibers to weave into their nests. The researchers decided to provide the birds with cotton treated with permethrin — a mild pesticide, commonly used to treat head lice in children, that is safe for birds — hoping the finches would incorporate the fibers in their nests. Finches near the test sites did just that, and their "self-fumigated" nests contained about half as many parasitic maggots — which infest and can kill newly-hatched chicks — compared to nests with untreated cotton. Darwin's finches and other bird species in the Galápagos have suffered steep population declines since the flies showed up in large numbers in the 1990s.
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.
02 May 2014:
Fracking May Induce Quakes at
Greater Distance than Previously Thought
Hydraulic fracturing and underground wastewater disposal may trigger earthquakes at tens of kilometers from the wells in which water is injected — a greater range than previously thought, according to new research from seismologists
. In one case, an earthquake
Fracking injection well in Louisiana
swarm in Oklahoma has been linked to a cluster of fracking injection wells up to 50 kilometers (31 miles) away, Cornell University researchers report. So-called "induced seismicity" — when human activity causes tremors in the earth's crust — is gaining attention as reports of earthquakes within the central and eastern U.S. have increased dramatically over the past few years. The rise coincides with increased hydraulic fracturing for oil and natural gas, and the injection of wastewater in deep disposal wells in many locations, including Colorado, Oklahoma, and Texas. According to the U.S. Geological Survey (USGS), an average rate of 100 earthquakes per year above a magnitude 3.0 occurred in the three years from 2010-2012, compared with an average rate of 21 events per year observed from 1967-2000.
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."
Carries on in Key Arctic Ecosystem
At a time of rapidly deteriorating relations between Russia and America, U.S. scientist Joel Berger continues his work with his Russian counterparts
Third in a series of blog posts from the Russian Arctic
on Siberia's Wrangel Island. In the third of three blog posts for Yale Environment 360
, Berger — a biologist with the Wildlife Conservation Society and the University of Montana — writes about efforts to better understand how rapid climate change might affect muskoxen and other wildlife in the Russian and North American Arctic. As Berger explains, a key focus of Russian-American scientific cooperation is Beringia, the region of northwestern Alaska and extreme northeastern Russia where two countries — and continents — are divided by the Bering Sea.
29 Apr 2014:
Exxon Mobil Arctic Project
Possibly At Risk Over Russia Sanctions
Exxon Mobil's development of a Russian Arctic oil project valued at nearly $900 billion is at risk following recent U.S. sanctions on Russian officials as a result of Ukraine's ongoing political crisis, Bloomberg News reports
. Exxon Mobil has partnered with the Russian state-controlled oil company OAO Rosneft to drill an oil-rich geological structure known as Universitetskaya, which contains an estimated 9 billion barrels of oil, valued at $900 billion at current market prices. Rosneft's CEO, Igor Sechin, a longtime member of Russian President Vladimir Putin's inner circle, was sanctioned by the U.S. yesterday, exposing the partnership with Exxon Mobil to additional scrutiny. Exxon Mobil and Rosneft are set to invest an estimated $600 million in drilling at the site in the Kara Sea, which would make the project Exxon's most expensive to-date. A U.S. Treasury official said yesterday that U.S. companies can still do business with Rosneft, but some analysts say Russian companies could become wary of working with Western corporations in the future. Exxon said last week that the project is on schedule.
28 Apr 2014:
Economic Viability of Nuclear
Power Under Threat, Energy Group Says
Nuclear reactors in the U.S. need a boost — either through carbon taxes or regulations forcing coal-fired plants to slash emissions — or economic factors will force many to close, according to a report
from a non-profit group. Nuclear power — currently the only major zero-carbon, around-the-clock baseload power source — supplies 19 percent of U.S. electricity and is key to meeting President Obama's pledge to reduce emissions 17 percent below 2005 levels by 2020, according to the Center for Climate and Energy Solutions. The economic viability of the 100 nuclear reactors in the U.S. is worsening, the report says, because of the abundance of cheap natural gas and rising wind energy production. A carbon tax or some form of carbon trading — for instance, requiring coal-fired plants to purchase and blend their electricity output with nuclear power — will be essential to keeping nuclear plants from closing before the end of their lifespans, the report contends. Four power companies recently announced the early retirement of five nuclear reactors, which constitute more than 4 percent of U.S. nuclear capacity, the group says.
25 Apr 2014:
Soils Release Far More CO2
Than Previously Thought, Researchers Find
As atmospheric CO2 levels rise, soils will likely store less carbon than scientists and climate models had predicted, according to new research
published in Science
. Scientists have long understood that rising carbon dioxide concentrations in the atmosphere spur
photosynthesis and plant growth, adding more carbon to the soil. Scientists had thought this soil carbon was relatively stable and could remain locked away
for centuries. But the new study, from researchers at Northern Arizona University shows that increasing soil carbon actually spurs microbes to produce more CO2. Higher atmospheric CO2 levels added roughly 20 percent more carbon to the soil, through increased photosynthesis, but they also increased carbon turnover by microbes by 16.5 percent. Many climate models had assumed that far more of the carbon absorbed by soils stayed there for long periods of time. "Our findings mean that nature is not as efficient in slowing global warming as we previously thought," the lead researcher said.
24 Apr 2014:
Browning of Congo Rainforest
Is Depicted in NASA Satellite Data
Persistent drought has taken a major toll on Africa's Congo rainforest, with large-scale browning intensifying and affecting a growing portion of the forest over the past decade, an analysis of NASA satellite data shows
browning trend significantly dwarfed smaller areas of "greening" — a satellite-derived indicator of forest health — during April, May, and June each year from 2000 to 2012, according to research published in Nature
. The browning of Congo's rainforest is significant, researchers said, because most climate models forecast that tropical forests may face increasing stress and rainfall shortages in a warmer and drier 21st century. A continued drying trend might alter the composition and structure of the Congo rainforest, affecting its biodiversity and carbon storage, according to the study. "Recent climate anomalies as a result of climate change and warming of the Atlantic Ocean have created severe droughts in the tropics, causing major impacts on forests," a NASA researcher said.
Five Questions for IPCC Chairman
On Future of Climate Change Action
The UN Intergovernmental Panel on Climate Change issued a report last month on steps the world can take
to avoid the worst impacts of future climate change. It was the final interim report before the IPCC’s major Fifth Assessment Report due to be released in October. Yale Environment 360
asked Rajendra K. Pachauri, who has served as IPCC chairman since 2002, five questions about the latest report and about the prospects that the international community will finally take decisive action to address climate change at talks scheduled in Paris in 2015.Read more.
22 Apr 2014:
Run-of-River Hydropower Set
For Big Gains, Turbine Maker Predicts
A type of hydroelectric technology known as "run-of-river" hydropower is set to grow 10-fold over the next decade
, potentially becoming a $1.4 billion industry,
Hugh Keenleyside Dam
according to Dutch turbine maker Tocardo International BV. Run-of-river hydropower stations redirect part of a waterway through a diversion to spin turbines and generate electricity. Run-of-river is considered a more benign type of hydropower than large dam projects because it is a smaller-scale technology that doesn't create large upstream reservoirs that flood ecosystems and disrupt a river's natural flow. Some conservation groups are concerned
that problems with migratory fish passage and other environmental issues could outweigh the power-generating potential of run-of-river hydro projects. The company implemented its first project to harness tidal streams at Den Oever, Holland, and it has been operating for five years.
21 Apr 2014:
Massive Data Crunch
Shows Steady Rise in Warmer Days
The proportion of days in the United States that are warmer than the long-term average increased from 42 percent in 1964 to 67 percent today,
according to an analysis of 3.2 million temperature anomalies over the last
50 years. Enigma.io
, a New York City-based company that specializes in searches of information from public databases, examined data from 2,716 U.S. weather stations to track the temperature anomalies. The company found that since 1964, temperature anomalies characterized as warm or “strong warm” have increased by an average of .5 percent a year. Enigma’s data show, for example, that in 2012, 84 percent of temperature anomalies in the U.S. skewed on the warm side. The company forecast that by the 2030s more than 70 percent of anomalous temperatures in the U.S. are likely to be higher than the historical average, rather than colder.
18 Apr 2014:
Scale and Extent of Dam Boom
In China Is Detailed in Mapping Project
China is planning to build at least 84 major dams in its southwest region, as shown in a map from the Wilson Center, eventually boosting its hydropower capacity by more than 160 gigawatts. By next year China's capacity
will surpass Europe's, and by 2020 it's projected to be larger than that of the U.S. and Europe combined. An interactive map
shows the scale and number of major dams proposed, under construction, existing, and canceled. The dam rush is part of an ongoing effort by China to increase non-fossil energy sources to 11.4 percent of the country's total energy consumption — a goal that has gained urgency due to severe air pollution in many northern Chinese cities. However, the hydropower push is not without its own major environmental consequences
, the Wilson Center notes. The cascades of planned dams will submerge important corridors connecting tropical rainforests to the Tibetan Plateau that allow wildlife to migrate as temperatures rise.
17 Apr 2014:
Five Kamchatka Volcanoes
Erupt Simultaneously, NASA Images Show
A NASA satellite passing over Russia's Kamchatka Peninsula this week photographed five simultaneous volcanic eruptions
. The erupting volcanoes, from north
to south, are Shiveluch, Klyuchevskaya, Bezymianny, Kizimen, and Karymsky. Karymsky, a 1,536-meter (5,039-foot) peak that has erupted regularly since 1996, is the most active of the five. The tallest, Klyuchevskaya, is 4,750 meters (15,580 feet) high. Of the planet's roughly 1,550 volcanoes that have erupted in the recent geologic past, 113 are found on the Kamchatka Peninsula, in Russia's far northeast, according to NASA. Forty volcanoes on Kamchatka are active, meaning they are either erupting now or capable of erupting at any time. Kamchatka's fiery landscape is driven by plate tectonics: The Pacific Plate is slowly colliding with and sliding beneath the Okhotsk Plate. As the Pacific Plate melts, magma migrates up toward the surface, causing volcanic eruptions.
Studying a Polar Menagerie
On an Island in Arctic Russia
Ninety miles from the Russian mainland and 300 miles above the Arctic Circle, Wrangel Island is home to an eclectic assortment of fauna and flora — muskoxen,
Second in a series of blog posts from the Russian Arctic
polar bears, wolves, reindeer, wolverines, walruses, Asia’s only population of snow geese, and 417 plant species. Joel Berger, a field biologist with the Wildlife Conservation Society and the University of Montana, spent several weeks on Wrangel Island this spring. In the second of three blog posts for e360
, he describes the arduous conditions under which Russian and U.S. scientists collect data on the island’s odd assortment of creatures.
15 Apr 2014:
Possible with Advances in Semiconductors
New semiconductor technology is advancing the development of house windows that could double as solar panels, according to scientists
from Los Alamos National Lab and Italy. Their research into so-called
Solar-harvesting materials under UV light
"quantum dots" — ultra-small bits of semiconductors that transmit energy extremely efficiently and can be tuned toward specific colors — shows that quantum dots can be used in transparent materials to harvest sunlight with efficiencies comparable to standard solar panels. When highly transparent materials are embedded with quantum dots, they are known as luminescent solar concentrators (LSCs); the structures can absorb sunlight and re-radiate it at longer wavelengths directed toward the edge of the slab, where the energy is collected by a solar cell. In tests using large LSC slabs (sized in tens of centimeters), researchers reported harvesting photons at roughly 10 percent efficiency. Typical photovoltaic solar panels have an average efficiency of about 15 percent.
14 Apr 2014:
Despite Stark Warnings,
UN Panel Finds Signs of Hope on Climate
Although greenhouse gas emissions continue to rise at an alarming rate, governments are beginning to embrace carbon-cutting initiatives, while technological advances are sharply reducing the cost of deploying solar and wind power, according to the latest report by the Intergovernmental Panel on Climate Change.
The working group report on climate mitigation
, released in Berlin, said that global CO2 emissions have risen about 2.2 percent a year this century — twice the rate of the last few decades of the 20th century — and that holding temperature increases to 2 degrees C (3.6 F) can only be achieved through an intensive push over the next 15 years. But the report also said that the political will to reduce carbon emissions seems to be rising around the world, and that shifting the global energy system from fossil fuels to zero- or low-carbon sources would reduce economic growth by only about .06 percent per year.
“The loss in consumption is relatively modest,” said IPCC chairman Rajendra Pachauri. “The longer we delay the higher would be the cost.”
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.
10 Apr 2014:
Mapping Program Helps
Cities See Money Saved by Planting Trees
New open-source software is helping cities better understand the benefits trees provide by calculating the value of the trees' ecosystem services, such as air quality improvements and CO2 storage. More than a dozen
cities have undertaken tree inventory initiatives, thanks to the OpenTreeMap software
, and residents have helped map more than 1.1 million trees worldwide. In addition to plotting a tree's location, users record its size, species, and other parameters that allow the software to calculate the tree's ecological value in terms of dollars saved through such benefits as cleaner air. San Diego's more than 340,000 mapped trees
, for example, are estimated to provide the city more than $7 million in benefits each year, including $4 million in air quality benefits and $2 million in reduced energy costs. In the coming months, the software will allow city managers to decide where to plant trees for maximum environmental benefit.
On Far-Flung Wrangel Island,
A Scientist Sizes up Muskoxen
As a field biologist for the University of Montana and the Wildlife Conservation Society, Joel Berger has been to his share of end-of-the-earth places. But few have
Muskoxen on Wrangel Island
rivaled Wrangel Island, the rugged, frozen outpost located 300 miles above the Arctic Circle in Russia’s extreme Far East. In the first of three reports for Yale e360
, Berger describes the arduous trip to Wrangel and the scientific work that has taken him there — research with Russian colleagues on the island’s 900 muskoxen, a shaggy beast that is a relic from the Pleistocene era. In subsequent reports, Berger will describe the motley assortment of wildlife that has colonized Wrangel and the contrasting impacts of climate change on eastern Siberia and Arctic Alaska.
08 Apr 2014:
'Living Fences' Dramatically
Cut Livestock and Lion Killings in Tanzania
A novel, low-tech idea is helping Tanzania's lion population rebound: So-called "living fences" — which enclose livestock and are constructed of actively growing trees and chain-link fencing — have cut lion
A Masai villager installs a living fence.
attacks and retaliatory killings by more than 85 percent in the areas they've been installed, the Guardian reports
. Traditionally, the Masai have built livestock enclosures out of thorny acacia trees, but those fences are relatively fragile. Chain-link fencing alone is more durable, but leopards and small lions can scale the fences, and hyenas can tunnel in below. By interweaving actively growing African myrrh trees with the chain link fencing, the Masai have created a barrier that lions can't climb over, and their root systems prevent predators from digging under the fence. Because livestock predation has been cut, communities that had been killing six or seven lions annually now kill, on average, less than one, leading to a rebound in lion populations.
A Personal Note on Peter Matthiessen,
Who Wrote Eloquently of the Natural World
For an editor, the prospect of working with Peter Matthiessen was intimidating. He was one of our finest writers, and he wrote with such poetic precision and lyrical grace that at first it felt presumptuous to propose
any changes to his writing at all. That feeling was heightened by his strong physical presence — an odd mix of Manhattan patrician, rugged outdoorsman, and Zen priest (all of which he was). And yet when I worked as his editor on several magazine articles in the 1990s, it was an immensely satisfying experience. He listened Zen-like, carefully considering all my editing suggestions (with him, they were suggestions
only), and to my delight, accepted almost all of them. Matthiessen died on April 5 at the age of 86, near the Long Island waters he so loved to fish. Read more of e360 editor Roger Cohn’s appreciation of Matthiessen.
07 Apr 2014:
Newfound Atmospheric 'Hole'
Threatens Polar Ozone Layer, Scientists Say
Researchers have discovered
a large opening in the Earth's atmosphere that is enabling pollutants to rise
Pacific atmosphere hole an elevator to the stratosphere
into the stratosphere and destroy ozone. The hole, which is in a part of the lower atmosphere called the "OH shield," is several thousand kilometers long and is centered over the tropical west Pacific Ocean. It's relatively close to Southeast Asia, a region with a booming population and rapidly increasing air pollution. The hole is a major concern because the OH shield usually scrubs air of chemical compounds emitted near the ground before they can reach the stratosphere, where those compounds can persist for long periods of time, reacting with and destroying ozone, say researchers at Germany's Alfred Wegener Institute who identified the hole. The newly discovered phenomenon acts as a sort of elevator, researchers say, drawing chlorofluorocarbons, sulfur dioxide, and other contaminants straight up to the stratosphere and bypassing the OH shield scrub.
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.
04 Apr 2014:
Solar Panels Could Beam Power
From Space Down to Earth, U.S. Navy Says
Researchers from the U.S. military are developing technology that would harvest solar energy in space and beam it down to Earth, according to
the Naval Research Laboratory. Although the concept seems futuristic, the
Navy is currently testing two prototype designs, both of which combine solar panels with electronic components that convert the energy to radio waves and transmit it to Earth. Eventually, engineers plan to use robotic vehicles to transport the panels to space and assemble them into a 1-kilometer wide satellite orbiting the planet. Theoretically, harvesting solar energy in space is more efficient than on Earth, because panels can collect sunlight around the clock and regardless of weather conditions. The U.S. military, currently the world's largest oil consumer, is eager to develop the technology to save money on fuel and simplify military deployments. But the private sector also has plans for the technology: California utility company Pacific Gas & Electric plans to buy space solar power by 2016.
03 Apr 2014:
Deforestation of Sandy Soils
Increases the Release of CO2, Study Finds
The texture of the soil that microbes live in determines how much carbon they release after deforestation, with sandy soils sending the most carbon into the atmosphere, according to research
led by Yale scientists.
Soils most affected by forest loss in red; least in yellow.
Subterranean microbes regulate carbon emissions from soil, and drastic changes to the microbial community, such as those that follow deforestation, can allow more CO2 to escape into the atmosphere and exacerbate global warming. The texture of soil, rather than such factors as temperature or nutrient concentrations, was the most important factor governing the release of CO2, the researchers found. Muddy, clay-like soils provide the most stable environment for microbial communities, likely because they're better at retaining nutrients than loose, sandy soils. The team used the findings to map areas in the U.S. where soil microbial communities would be most and least affected by deforestation, which could help inform land management practices.
Comment: e360 Point/Counterpoint Debate
On University Fossil Fuel Divestment
Scientists Charles H. Greene, of Cornell University, and Daniel M. Kammen, of the University of California, Berkeley, offer commentary on the recent Yale Environment 360 Point
articles on the
Student protest at Tufts University last spring
issue of whether universities should take a stand against climate change by divesting from companies that produce oil, natural gas, or coal. Greene and Kammen make the case that the movement to divest is gaining ground on U.S. campuses and will eventually succeed because fossil fuels are increasingly seen as a potentially risky investment. "We predict that divestment at the nation’s colleges and universities will occur much more rapidly than anybody imagined at the start of the campaign just over a year ago," they write. Read their comment.
01 Apr 2014:
Delaware River Watershed
Is Focus Of Large-Scale Restoration Project
A Philadelphia foundation is providing $35 million to launch a host of programs aimed at better protecting the Delaware River
, which flows through the heart of
Delaware River at Trenton, New Jersey
the populous U.S. eastern seaboard and provides drinking water for 15 million people. The William Penn Foundation, working with nonprofit groups such as The Open Space Institute, says its Delaware River Initiative will protect more than 30,000 acres of land, launch 40 restoration projects, create incentives for businesses and landowners to protect the watershed, and set up a comprehensive program of water quality monitoring that will enable the foundation and its partners to measure the success of their programs and the overall health of the river. A cornerstone of the foundation’s initiative will be its restoration and protection work in eight so-called “sub-watersheds” that feed into the Delaware River.
31 Mar 2014:
IPCC Issues Stark Report
On Present and Future Climate Impacts
Rapidly rising levels of greenhouse gases are already having a major impact on the earth’s natural systems and the problem is likely to grow significantly worse
unless these emissions are brought under control, according to a new report by the Intergovernmental Panel on Climate Change (IPCC). The report
, released in Yokohama, Japan, said that steadily rising temperatures are melting polar ice caps, sharply diminishing Arctic sea ice, intensifying heat waves and heavy rains, causing the death of coral reefs, and placing water and food supplies under stress. The report on climate impacts, drafted by several hundred of the world’s leading climate scientists, emphasized that the world’s food supply is at considerable risk. Already, the report said, heat waves and water stress are affecting the output of wheat and corn on a global scale, impacts that are only expected to intensify in the future, further exacerbating food shortages. “Nobody on this planet is going to be untouched by the impacts of climate change,” said IPCC chairman Rajendra K. Pachauri.
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.