Antarctica and the Arctic
29 Jul 2016:
Changing Artic Tundra Could
Radically Alter Shorebird Breeding Grounds
A new study projects that global warming could dramatically affect the tundra breeding habitat of 24 shorebird species, with 66 percent to 83 percent losing most of their suitable nesting territories.
Shifts in Arctic shorebirds.
Researchers modeled breeding conditions for these migratory shorebird species — some of which travel more than 10,000 miles from Antarctica or southern South America to breed in the Arctic — and compared projected 21st century conditions to the last major warming event more than 6,000 years ago. The study, published in Global Change Biology
, concluded that a warming and drying tundra could force many species to shift their breeding territories to the Arctic coastline by 2070, causing some birds to completely change their migration routes. “Climate change is also opening up the Arctic to threats such as mining and tourism, and we must make sure we protect key places for all Arctic species, including these amazing migratory birds,” lead author Hannah Wauchope said in a University of Queensland press release
20 Jul 2016:
Global Temperatures Continue
To Shatter Heat and Arctic Ice Records
June marked the 14th consecutive month of record-breaking heat, with global temperatures measuring 1.62 degrees F above the 20th-century average, NASA and the National Oceanic and Atmospheric Administration announced this week
Global 2016 temperatures.
The first half of 2016 was 1.89 degrees F above last century’s average, breaking the previous January-June record set in 2015 of 0.36 degrees F above average. “2016 has really blown  out of the water,” Gavin Schmidt, director of NASA's Goddard Institute for Space Studies, told reporters
. Five of the first six months of this year have also set records for the smallest Arctic sea ice extent since satellite records began in 1979. Scientists said the recent record-breaking heat could be partly attributed to last year’s strong El Nino, but not entirely. “While the El Niño event… this winter gave a boost to global temperatures from October onwards, it is the underlying trend which is producing these record numbers,” Schmidt said
12 Jul 2016:
Climate Change Has Shifted
The World’s Cloud Cover Over Past 30 Years
Warming global temperatures have altered the distribution of clouds across the Earth in recent decades, according to new research published in the journal Nature
Global cloud cover.
Mid-latitude storm clouds have shifted polewards, dry subtropical zones have expanded in size, and the tops of clouds have gotten higher as a result of a warmer troposphere and cooler stratosphere, according to the study, which relied on satellite images taken between 1983 and 2009. Researchers said these shifts in cloud cover could further exacerbate climate change. As cloud systems shift toward the poles, where there’s less solar radiation, more sunlight will reach the Earth’s surface near the equator, boosting temperatures. Also, taller, thicker clouds trap more heat. “We now have a thicker blanket, which is also a warming effect,” said Joel Norris
, a climate scientist at the Scripps Institution of Oceanography in San Diego who helped lead the study.
08 Jun 2016:
Sea Ice Hits New Spring Low
In the Arctic, Says Federal Agency
Sea ice extent in the Arctic hit a new record spring low last month, measuring 537,000 square miles below average — an area twice the size of Texas, the National Snow and Ice Data Center announced this week
Sea ice breaking up in the Beaufort Sea in May.
Last month’s Arctic sea ice extent was the lowest May sea ice measurement since satellite monitoring began 38 years ago and follows a string of record low ice this winter. “We didn’t just break the old May record, we’re way below the previous one,” NSIDC Director Mark Serreze told Climate Central
. The Arctic’s snow cover also hit record lows this year, with April having the lowest snow cover for that month on record and May the fourth lowest. The Arctic has warmed twice as fast as the rest of the world in recent decades, but scientists say that this year’s strong El Niño in the Pacific Ocean could be ramping up temperatures even more. Temperatures at the pole have been 4 to 11 degrees F above average
this winter. “Will we end up with very low sea ice extent this September?” Serreze said. “I think pretty much absolutely.”
06 Jun 2016:
Fish Choose Plastic Over
Zooplankton in Polluted Waters
Fish that grow up in waters full of plastic particles develop a taste for trash, choosing to eat plastic over zooplankton, their natural food source, according to a study published in the journal Science
The research, by ecologists at Uppsala University in Swedish, found larval perch from the Baltic Sea exposed to microplastic pollution (less than 5mm in size) had stunted growth, were less active, ignored the smell of predators, and experienced increased mortality rates. Plastic pollution has become a major problem in the world’s oceans, but scientists are just beginning to understand how these fragments can affect the health of marine species. “If early life-history stages of other species are similarly affected by microplastics, and this translates to increased mortality rates, the effects on aquatic ecosystems could be profound,” said ecologist Oona Lönnstedt
, lead author of the study.
23 May 2016:
World Could Warm 8 Degrees
Celsius If All Fossil Fuel Reserves Burned
As nations meet in Bonn, Germany this week to hash out how to achieve the 2-degree Celsius goal they set in Paris, new research is providing policymakers a glimpse of what would happen if the world does nothing to curb climate change.
What if nations chose instead to burn through all of their remaining fossil fuel reserves, equal to 5 trillion tons of CO2 emissions? According to the new study published in the journal Nature Climate Change
, the world would warm an average 8 degrees Celsius (14.4 degrees F), or up to 17 degrees Celsius (30 degrees F) in the Arctic. The research was conducted by a team of climate scientists at the University of Victoria and Simon Fraser University in British Columbia who wanted to understand the worst-case scenario. “Such climate changes, if realized, would have extremely profound impacts on ecosystems, human health, agriculture, economies, and other sectors,” the researchers write.
Interview: CO2 'Air Capture' Could
Be Key to Slowing Global Warming
For two decades, Klaus Lackner has pioneered efforts to combat climate change by pulling carbon dioxide from the atmosphere.
Now, after years of watching the global community fail to bring greenhouse gas emissions under control, Lackner — director of the Center for Negative Carbon Emissions at Arizona State University — is delivering a blunt message: The best hope to avoid major disruptions from global warming is to launch a massive program of CO2 "air capture" that will begin to reverse the buildup of billions of tons of carbon in our atmosphere. "We need to have the ability to walk this backwards," says Lackner. "I'm saying this is a war, and we need to use all the weapons at our disposal. You don't want to get into this fight with one hand tied behind your back."
Read the interview.
10 May 2016:
More than 2,000 New
Plant Species Are Found Every Year
There are currently 391,000 plant species known to science—and another 2,000 are being discovered every year, according to a new report from the U.K.’s Royal Botanic Gardens, Kew.
Last year’s new discoveries included a nearly five-foot tall carnivorous plant first identified on Facebook, a 105-ton tree in West Africa, and 90 new species of Begonia flowers. Brazil, Australia, and China were hotspots for species discovery. The State of the World’s Plants
report did find, however, that one-fifth of the world’s plant species are at risk of extinction from habitat loss, disease, invasive species, and climate change. “Plants are absolutely fundamental to humankind,” Kathy Willis, director of science at Kew, told The Guardian
. “Plants provide us with everything — food, fuel, medicines, timber, and they are incredibly important for our climate regulation. We are facing some devastating realities if we do not take stock and re-examine our priorities and efforts.”
05 May 2016:
With Climate Change, It Is
Survival of the Oldest, Not the Fittest
When it comes to climate change, the world’s oldest species are more likely to survive than newly evolved ones, says a new study
published in the journal BMC Evolutionary Biology
The logic is relatively simple: The reason they’re so old is that they’ve been tested by abrupt environmental shifts before and have come out on top. This group includes species like the cane toad and California sea lion. More specifically, the study found the planet’s oldest animals all share at least one of the following characteristics: They come in various colors, give birth to live young (as opposed to eggs), and live at low latitudes. The research could help “predict which [species] could be better able to deal with current climate change and to better predict the threat status of species on the red list of the International Union for Conservation of Nature,” said
Sylvain Dubey, an ecologist at the University of Lausanne in Switzerland and co-author of the new study.
28 Apr 2016:
Half of All Farmed Fish Have
Deformed Ear Bones That Cause Hearing Loss
Farmed fish have become an increasingly larger share of the world’s seafood market in recent decades—now accounting for 50 percent of global seafood consumption.
At the same time, however, debate about the ethics, safety and health of farmed fish versus their wild counterparts has also intensified. A new study
published in the journal Nature Scientific Reports
finds that half of all farmed Atlantic salmon have deformed ear bones that lead to hearing loss. These salmon are 10 times more likely to have the deformity than wild fish. The findings “raise questions about the welfare of farmed animals," said
Tim Dempster, a biologist at the University of Melbourne involved in the study. It may also explain why efforts to boost wild populations by releasing farmed juveniles have proven unsuccessful. Hearing loss would prevent farmed fish from detecting predators, or restrict their ability to navigate to breeding sites, the scientists said.
25 Apr 2016:
Scientists Discover Antarctic
Lake That Could Contain Unique Life Forms
Scientists have discovered what they think is a massive, ribbon-shaped lake under the Antarctic ice sheet that could lead to the discovery of a bevy of new unique life forms.
The lake, which measures 60 miles long by 6 miles wide, was discovered using satellite imagery, and scientists plan to confirm its existence using ice-penetrating radar this spring. The lake has likely been locked under the ice for millions of years — allowing bacteria and other life forms to evolve in complete isolation from the rest of the world, according to a report released at the European Geosciences Union meeting. Unlike the continent’s largest under-ice lake, Vostok, the newly discovered waterbody — located in East Antarctica — is relatively close to a research station, making it easier to explore. “It’s the last un-researched part of Antarctica, so it’s very exciting news,” Bryn Hubbard of the University of Aberystwyth UK told the New Scientist
20 Apr 2016:
Entries Invited for Third
Annual Yale Environment 360 Video Contest
The third annual Yale Environment 360
Video Contest is now accepting entries. The contest honors the year's best environmental videos. Submissions must focus on an environmental issue or theme, have not been widely viewed online, and be a maximum of 15 minutes in length. Videos that are funded by an organization or company and are primarily about that organization or company are not eligible. 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 contest judges will be Yale Environment 360
editor Roger Cohn, New Yorker
writer and e360
contributor Elizabeth Kolbert, and documentary filmmaker Thomas Lennon. Deadline for entries is June 10, 2016. Read More.
12 Apr 2016:
Scientists Reimagine The
Tree of Life With New Microbe Knowledge
Following years of intense exploration and research into the microbial world, scientists have reimagined the tree of life
—the iconic visual representation of the living world first proposed by Charles Darwin in 1859.
The new tree of life.
The project was led by researchers at the University of California, Berkeley, who over the last decade have been gathering DNA from across the globe—from everywhere from meadow soils and river mud to deep sea vents—to reconstruct genomes and describe thousands of new microbial species. Curious how their findings fit into the tree of life, the scientists used a supercomputer
to visualize how more than 3,000 new and known species related to one another. They discovered that eukaryotes, the group that includes humans, exist on a thin twig compared to the microbial branch of the tree. “The tree of life as we know it has dramatically expanded due to new genomic sampling of previously enigmatic or unknown microbial lineages,” the authors wrote
For James Hansen, the Science
Demands Activism on Climate
Climate scientist James Hansen has been a prominent figure in the global climate conversation for more than 40 years. His 1988 congressional testimony on climate change helped introduce the problem of rising greenhouse gas emissions to the American public,
and he has led study after study examining how our world will change as a result of global warming. Eight years ago, Hansen made the rare decision to begin engaging in climate activism—a move that has earned him both praise and criticism from the media and scientific community. In an interview with Yale Environment 360
last week, Hansen opened up about his unconventional career path and what he believes the world could look like a century from now. “I don't think that I have been alarmist — maybe alarming, but I don't think I'm an alarmist,” he said. “We have a society in which most people have become unable to understand or appreciate science, and partly that's a communication problem, which we need to try to alleviate.”
Read the interview.
07 Apr 2016:
How Ancient Algae Could
Help Cure Brain and Breast Cancer
One of the oldest life forms on earth may hold the key to battling hard-to-treat cancers, according to new research
by scientists at Oregon State University. The compound, coibamide A, is found in blue-green algae, organisms that have existed for at least two billion years. It was found during a diving trip in Panama’s Coiba National Park eight years ago and run through the National Cancer Institute’s database of potential anti-cancer compounds. Coibamide A was tested on mice and found to be more effective at killing brain and triple negative breast cancer cells—two of the most aggressive and hard-to-treat types of the disease—than anything ever tested before. "The chemical diversity found in nature has always been a significant source of inspiration for drug design and development, but… marine environments remain relatively unexplored," said Jane Ishmael, a cellular biologist at Oregon State University and lead author of the new study.
06 Apr 2016:
Half of World Heritage Sites Are
Threatened By Industrial Development
Since 1972, the United Nations has worked to protect 229 locations in 96 countries known for their “exceptional natural beauty” and “cultural significance.” These spots, known as World Heritage Sites,
The Great Barrier Reef
range from Mount Kilimanjaro in Tanzania to the Great Barrier Reef in Australia, China’s panda sanctuaries, and the Grand Canyon in the United States. A new survey by the World Wildlife Fund, however, has found half of these sites are under threat
from oil and gas development, mining, illegal logging, overfishing, or other industrial activities. Eleven million people live in or near these sites, the report says, and depend on them for their housing, food, water, jobs, or ecosystem services like flood protection and CO2 sequestration. “We are not going to develop a just and prosperous future, nor defeat poverty and improve health, in a weakened or destroyed natural environment,” the authors wrote.
01 Apr 2016:
Scientists Study the Skies
To Create a Map of the World’s Biomes
Curious where certain species live? Don’t look down. Rather, study the skies, according to new research published in the journal PLoS Biology
. Scientists from the University of Buffalo and Yale University
used images from NASA satellites to build a database of cloud cover for every square kilometer of the planet from 2000 to 2014. They then used the information to map the world’s biomes. They found that cloud patterns are a much more accurate way of predicting species distribution than using extrapolated on-the-ground observations, the method most conservationists use today. “Sunlight drives almost every aspect of ecology,” Adam Wilson, an ecologist at the University of Buffalo who led the study, told New Scientist
. “So when you put something in between the sun and plants, that is going to have implications on the amount of energy they are receiving, soil moisture, leaf wetness, and humidity—almost everything that is important.”
Interview: How Ocean Noise
Wreaks Havoc on Marine Life
Bowing to public pressure, the Obama administration recently reversed an earlier decision to allow oil drilling off the U.S. East Coast. But the five-year moratorium on drilling does not prohibit exploratory seismic air gun surveys
used to locate oil and gas reserves under the seabed, and those surveys are expected to be authorized this spring. Cornell University marine bioacoustics expert Christopher Clark says the testing, which can go on for weeks at a time, will only add to the rising din in the oceans. “Imagine that every 10 seconds there is an explosion that is rattling grandma’s china out of the cupboard,” he says, “and it is falling on the floor.” In an interview with Yale Environment 360
, Clark explains how noise, most of it from ship traffic, severely disrupts marine life, especially among whales. But the good news, he says, is that technologies are being developed to drastically reduce the noise from ships and geological surveying.
Read the interview.
23 Mar 2016:
Microbes Are Likely Speeding
Up the Melting of the Glaciers
As if soaring global temperatures weren’t bad enough, scientists reported this week that microbes are also speeding up the melting of Arctic ice.
National Parks Service
A pool of meltwater on the Root Glacier in Alaska.
The problem lies in cryoconite, the soil-like composite of dust, industrial soot and photosynthetic bacteria that darkens the surface of ice and causes it to melt, scientists from Aberystwyth University in Wales said. As it melts, ice leaves behind small water-filled holes full of bacteria. The sun-loving microbes then shape the pockmarks’ depth and size to get more light exposure, in turn melting the ice even more—a process previously unaccounted for in global climate change models. "It's only recently that we've begun to understand that these cryoconite holes are dynamic, changing in size and shape,” said
biologist Arwyn Edwards, who led the study. "In the long term, this contributes to the loss of glacier habitats, and the unique microbial biodiversity living on them."
21 Mar 2016:
Newly Discovered Butterfly
Could Be Climate Bellwether in the Arctic
Scientists have discovered the first new butterfly species in Alaska in nearly 28 years, according to new research
published in the Journal of Research on the Lepidoptera
The dorsal side of new species Oeneis tanana.
Named the Tanana Arctic, or Oeneis tanana
, the species is thought to be a hybrid and the only butterfly endemic to the state. Because butterflies are so sensitive to environmental change, the Tanana Arctic could serve as an early warning signal to the impacts of climate change in the region, the scientists said. “This butterfly has apparently lived in the Tanana River valley for so long that if it ever moves out, we’ll be able to say ‘Wow, there are some changes happening,’” said
Andrew Warren, the senior collections manager at the McGuire Center for Lepidoptera and Biodiversity at the Florida Museum of Natural History who discovered the species. “This is a region where the permafrost is already melting and the climate is changing.”
17 Mar 2016:
The World’s Economy Grew,
But Greenhouse Gas Emissions Didn't
Despite a 3.1 percent growth in global GDP in 2015, greenhouse gas emissions remained flat for the second year in a row, according to the International Energy Agency.
A man installs new solar panels in Oregon.
The decoupling of emissions from economic growth is “welcome news,” IEA executive director Fatih Birol said in the press statement. “Coming just a few months after the landmark COP21 agreement in Paris, this is yet another boost to the global fight against climate change.” The world’s nations released 32.1 billion metric tons of greenhouse gases last year, equal to—or perhaps even a slight downtick from—2014, the agency said. The stabilization is likely due to the booming renewable energy industry and global cutbacks on the use of coal, particularly in the U.S. and China, the two largest emitters of carbon dioxide. Chinese emissions, for example, declined 1.5 percent last year.
08 Mar 2016:
JP Morgan Will No Longer Invest
In New Coal Mines, Citing Climate Change
JP Morgan will no longer finance new coal mines or support new coal-fired power plants in “high income” countries, the banking giant said
in a policy statement on its website.
Coal mine in Jharia, India
Bank of America, Citigroup, Morgan Stanley and Wells Fargo have made similar pledges in recent months, all part of a larger divestment movement aimed at transitioning the world’s economies off fossil fuels. The anti-coal campaign has dealt a blow to an already struggling industry. The price of coal has dropped from $140 per ton in 2009 to $42 in 2016 as cheap, abundant natural gas and renewables have flooded the U.S. energy market. At the same time, support for climate action has grown, with the signing of an international climate agreement in Paris last December. “We believe the financial services sector has an important role to play as governments implement policies to combat climate change,” JPMorgan said
in the document.
09 Feb 2016:
Ice-Free Arctic Trade Route
Unlikely For Decades to Come, Study says
Despite the impact climate change is having on Arctic sea ice, it will be decades before big cargo ships will be able to take an ice-free shortcut
Russian tanker making its way through ice.
across the Arctic Ocean, according to a new report from the Arctic Institute
. In recent years, countries have been vying for access to possible Arctic shipping lanes in the belief that use of the passage was more imminent and would contribute to shorter travel times and associated cost savings
. But given the Arctic’s short sailing season, continuing treacherous ice conditions, the high costs associated with armoring cargo ships to withstand the ice, as well as low fuel prices, the Institute predicts that such crossings won’t become commercially viable until at least 2040. Until that time, shipping between Europe and Asia will continue to use the Suez Canal. Arctic shipping has decreased in recent years, from 1.3 metric tons in 2013 to 300,000 tons in 2014.
18 Nov 2015:
Icelandic Ice Cap Gains Mass for
First Time in Two Decades, Researchers Say
An Icelandic ice cap known as Hofsjökull, shown in this NASA satellite image, has gained mass for the first time since 1993,
Iceland's Hofsjökull ice cap
measurements taken last month. All ice caps in Iceland had been retreating rapidly and losing volume since 1995, due to decreasing precipitation and rising temperatures. Hofsjökull’s resurgence this year is the result of abundant winter precipitation and cooler than normal summer temperatures, explained Thorsteinn Thorsteinsson, a glaciologist at the Icelandic Meteorologial Office. Last winter, snowfall in the region of the ice cap was 25 to 60 percent thicker than the 1995-2014 average. Cool northerly winds slowed Hofsjökull’s summer melt rate, contributing to the positive measurements obtained last month.
13 Oct 2015:
Antarctic Ice Shelves Face
Major Threat If CO2 Emissions Keep Rising
A new study says that many of Antarctica’s floating ice shelves — which play a key role in holding back vast amounts of land-based ice — could become highly unstable
later this century if greenhouse gas emissions are not sharply reduced. An international team of researchers, reporting in Nature Geoscience
, said that surface melting of Antarctica’s ice shelves could reach the point where many could disintegrate. Such surface melting has already led to the collapse of numerous ice shelves along the rapidly warming Antarctic Peninsula. The study said that surface melting of the continent’s ice sheets would double by 2050
under both intermediate- and high-emissions scenarios. After that, the fate of the ice shelves diverges sharply depending on emissions levels, with a high-emissions scenario leading to surface melting equaling or exceeding intensities associated with ice shelf collapse. Loss of the ice shelves could lead to major increases in sea level as inland glaciers flow to the sea, scientists say.
05 Oct 2015:
Icelandic Seafood Giant
May Be Involved in Endangered Whale Hunt
Iceland’s controversial annual hunt of fin whales — classified as "endangered" by the International Union for Conservation
of Nature — ended with a catch of 155 fin whales, the largest slaughter since the 1986 moratorium on commercial whaling, reports the London-based advocacy group Environmental Investigation Agency (EIA). The EIA and the Animal Welfare Institute obtained evidence
revealing the ongoing involvement of international seafood giant HB Grandi — a Reykjavík-based company with an annual income of roughly $230 million (as of 2011) — in the whaling business, despite its claims to the contrary. HB Grandi is Iceland’s largest seafood company and its CEO has repeatedly insisted that the company “is not involved in whaling and never has been.” Despite the international moratorium, Iceland recently has allowed commercial whaling and has shipped whale products to Japan.
28 Sep 2015:
Shell Ends Arctic Oil and Gas
Exploration Bid for Foreseeable Future
Shell Oil has announced
that it will stop its controversial exploratory drilling for oil and gas in Arctic waters for the foreseeable
Shell's Polar Pioneer rig as it left Seattle for the Arctic
future, saying in a statement that the reserves it had discovered were not “sufficient to warrant further exploration.” Shell began operating its first exploration well on July 30, 2015, in the Chukchi Sea off the northwestern coast of Alaska. But the company reported that although it had found indications of the presence of oil and gas, the reserves in the basin where they were drilling were, in the words of one company official, "clearly disappointing." Under Shell's federally approved exploration plan, all rigs and support vessels must leave the Chukchi Sea before the end of October. Environmental groups hailed Shell's announcement.
22 Sep 2015:
Antarctic Seafloor Life Is
Locking Away a Lot of Carbon, Study Says
The loss of sea ice over Antarctic waters has caused certain forms of life to flourish on the seafloor, and those underwater communities
An Antarctic icefish swimming over bryozoans
are acting as important and unexpected carbon sinks, according to research published in the journal Current Biology
. Based on studies of West Antarctic bryozoans — aquatic invertebrates sometimes referred to as "moss animals" — researchers have found that those and other seafloor organisms could play important roles in accumulating and burying carbon, removing it from the atmosphere for an extremely long time. The researchers calculate that growth of the bryozoans has nearly doubled over the past 20 years, with the animals taking in more than 200,000 tons of carbon per year since the 1980s. Accounting for other undersea species, the researchers suggest that roughly 3 million tons of carbon are sequestered each year, equivalent to nearly 200 square miles of tropical rainforest.
18 Sep 2015:
Genes of Greenlanders Preserve
Evidence of Ancient Arctic Adaptation
The DNA of modern-day Greenlanders shows how their Inuit forefathers adapted to the harsh Arctic environment they called home
80% of Greenlanders identify as Inuit.
for thousands of years, according to findings published in the journal Science
. The Arctic is an extreme environment, characterized by a cold climate and sparse vegetation. The typical diet of Greenlanders — and their ancient ancestors — is made up primarily of proteins and fats from fish and marine mammals, and carbohydrate and vegetable consumption is minimal. By collecting genetic information from 4,500 modern Greenlanders, researchers determined which genes have changed the most over the roughly 20,000 years since Greenlanders' most ancient Inuit ancestors separated from their nearest East Asian relatives, the Han Chinese. The genetic changes the researchers identified show that through natural selection the Greenlandic Inuit's genetic makeup evolved in a way that enabled them to efficiently metabolize the fatty acids from fish and to live with few carbohydrates and vegetables.
In Northern Canada Peaks, Scientists
Are Tracking Impact of Vanishing Ice
Earlier this month, a team of Canadian scientists braved a cold-weather thunderstorm, snow, rain, and high winds to spend a week working on the last extensive icefield in the interior of the Northwest Territories. Accompanying them was Yale Environment 360
contributor Ed Struzik, who reports on the trip and the importance of the research team’s investigations. The group worked on the Brintnell/Bologna icefield, which has shrunk by more than a third over the last three decades and continues to melt at a rapid clip. The scientists hope to determine how the melting of these glaciers and the loss of snowpack in the surrounding mountains might affect the region’s ecology and rivers, including the huge Mackenzie River, Canada’s largest.