Categories
Arctic Change

Arctic Worries

George Divoky frets–with good reason. In 2016, CNN Correspondent John D. Sutter called him the man who is watching the world melt. The description is as distressing as it is apt.

George sends us regular dispatches from a small field camp on Cooper Island, about 25 miles east of Utqiaġvik, where he has studied a colony of nesting Mandt’s Black Guillemots for the last 44 years. Since his work began in 1975, the research has morphed into one of the longest-running studies of seabirds, sea ice, and climate change.

Guillemots look like small penguins headed off to a fancy party replete with ice sculptures and all-night dancing. Unlike other seabirds that migrate out of the region seasonally, they live out over the frigid waters year-round, only returning to land to breed and fledge their young–this makes them an excellent indicator of how climate change is impacting the Arctic.

Weather delayed the start of this research season in early June. While warm temperatures in the Arctic have made headlines in recent months, unusually late snow and ice kept the guillemots from reaching their nesting boxes until mid-June; the first egg was laid on June 24.

His communications are tinged with an effort to buoy spirits–I’m guessing his own more so than ours. This week, the bad news came first: a 29-year-old female died. He wrote that she had been banded during the first George Bush administration. (While many humans rely on a simple Gregorian calendar, George’s memories appear to be synchronized according to a timeline rooted firmly in geopolitics.)

Bad news was followed with happy; two siblings from the 2014 cohort returned and recruited partners for breeding.

Otherwise, it’s been a stormy week on the island. On July 20, he wrote that the wind was finally dying down. A bad week for the infrastructure, the camp’s weather station was blown over and part of the heavy-duty WeatherPort tarp separated from the frame, which caused a number of things to get wet. On Wednesday he saw record high rainfall for that date.

Egg laying hit an all-time low this year, with fewer breeding pairs than any previous year.

He’s asking questions about how changing ice conditions will impact these seabirds – his seabirds. In his most recent field report, he spoke at length about the relationship between the guillemots and nearshore sea ice. The location of the sea ice impacts how far parents will have to fly to access suitable prey for their chicks. Increased travel time means greater energy expended by parents – for seabirds that live predominantly out in open waters, it’s all about balancing resources and energy. The presence or absence of sea ice combined with the temperature of the ocean waters impacts the availability of Arctic Cod, the small nutritious fish the guillemots prefer.

George hopes the slowly departing nearshore sea ice will keep ideal prey in foraging range for the seabirds. He wrote, the cod is “urgently needed for the colony to reduce its current population decline.”

David Douglas is a research wildlife biologist for United States Geological Survey (USGS) Alaska Science Center; he and George are frequent collaborators. This week he emailed the MODIS images displayed above and wrote that Cooper Island was pretty well surrounded until July 16 when the persistent ice immediately around the island broke up and melted.

Studies like George’s will help scientists to better understand the ramifications of long-term warming and less sea ice for wildlife in the region. Impacts to wildlife will directly affect the lives of the people who depend on subsistence fishing and hunting for survival.

Warming Arctic conditions have persisted with 2018 reaching record lows for sea ice extent, according to a report published by NOAA and University of Alaska Fairbanks’s International Arctic Research Center.

Late ice formation and early retreat in the Chukchi and Bering Seas impacted local communities by making travel for subsistence hunting and fishing dangerous and, at times, impossible. Storm damage and erosion was worsened by exposed shorelines, left unprotected by a lack of sea ice. Island villages and coastal communities experienced flooding and property damage as well. You can read more about the storm impacts here and here.

The report attributes late and minimal ice coverage to warmer temperatures, particularly over the last four years. Increased temperatures combined with stronger storms helped break up weaker ice.

In 2018, there was less sea ice in the Bering Sea than any year since 1850, when commercial whalers began recording this data. Experts agree, loss of sea ice is a result of climate change. Continued warming creates a feedback loop where warming temperatures melt ice; without a reflective snow and ice covering, the ocean absorbs more of the sun’s warming rays and temperatures continue to rise.

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Sea ice since 1850. Image Credit: NOAA and University of Alaska Fairbanks International Arctic Research Center (UAF-IARC).

As for future winters, what can people expect to see if warming continues at current rates?

“Communities need to prepare for more winters with low sea ice and stormy conditions. Although not every winter will be like this one,” concludes the report, “there will likely be similar winters in the future. Ice formation will likely remain low if warm water temperatures in the Bering Sea continue.”

And for George’s seabirds? How many birds will successfully fledge this year? How many will return next?

We’ll just have to wait and see.


This piece is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.


Read More

Historic Low Sea Ice in the Bering Sea by Kathryn Hansen for NASA Earth Observatory

Arctic Sea Ice a Major Determinant in Mandt’s Black Guillemot Movement and Distribution During Non-Breeding Season By G. J. Divoky, D.C. Douglas, and I.J. Stenhouse

Melting Arctic Sends a Message: Climate Change Is Here In a Big Way by Mark Serreze

The First Frontier: Creating a Climate Displacement Fund for Displaced Alaska Communities By Wen Hoe

Categories
Arctic Change

Seabirds and Sea Ice

MODIS June
MODIS image from June 5; snow and ice have blue/cyan color, while clouds will be lighter gray/white. Image Credit: David Douglass/USGS

Over most of its range the Black Guillemot is a nearshore seabird, occupying coastal waters during both the breeding and nonbreeding seasons, as do other members of the genus Cepphus. Pelagic or open ocean waters can offer abundant prey resources, but these options are often distant, patchy and unpredictable.

The nearshore typically offers seabirds a smaller but more reliable source prey base consisting of forage fish and benthic fauna from the ocean floor such as crustaceans or mussels.

The Arctic Ocean has extensive sea ice cover in the nearshore for the majority of the year; this presents a number of challenges to a nearshore species. Our work on the Cooper Island Black Guillemots has revealed a number of ways in which the species has met these challenges.

The current view from my cabin window illustrates one of the major problems guillemots face in the Arctic. Sea ice extends from the north beach of the island to the horizon and covers Elson Lagoon to the south. The only water available to the guillemots is a brackish pond in the center of the colony that provides no prey but is deep enough to provide sanctuary if the guillemots need to dive when pursued by an owl or falcon — regular visitors to the island.

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MODIS image from July 9; snow and ice have blue/cyan color, while clouds will be lighter gray/white. Image Credit: David Douglass/USGS

While guillemots arrived on the island almost a month ago and egg laying is now complete, until recently the closest predictable open water where guillemots could find prey was approximately 20 miles away, off Point Barrow where winds and currents shift the sea ice creating an area of open water. This opening is called a lead. The Cooper Island guillemots stage there in April and May before coming to the island. (Editor’s note: Leads are important for wildlife, because they allow for access to oxygen in the case of seals and walruses and prey in the case of seabirds; you can read more from the National Snow and Ice Data Center here.)

This distance between the Cooper Island guillemots’ nesting colony and access to their prey resources during egg laying and incubation is in sharp contrast to what guillemots breeding in subarctic or temperate waters find at their breeding colonies. These birds occupy waters directly adjacent to colonies well before egg laying and foraging areas may even be within sight of nests. The birds breeding on Cooper Island (and likely all colonies of Mandt’s Black Guillemot Cepphus grylle mandti, the high Arctic subspecies of Black Guillemot) have responded to this spatial disconnect by having a well-defined periodicity in their daily colony attendance. Every day, the parent not incubating eggs and all nonbreeding individuals vacate the colony from approximately noon until midnight. The birds fly individually or in small groups to open water where they can feed for almost half the day before returning to the colony just as the “midnight sun” is at its lowest point in the sky.

BeachwCases 2015
Cooper Island beach with nesting boxes from 2015. Image Credit: George Divoky

While it seems individual birds could fly offshore to open water to feed anytime during the day, there are a number of possible reasons the observed colony-wide pattern of attendance and abandonment developed. For the half of the day when the guillemots are absent – from approximately noon to midnight – there is no evidence that Cooper Island supports a colony of Black Guillemots. It appears to be just a barren sandbar that happens to inexplicably have 200 scattered black plastic cases along with a small cabin surrounded by a bear fence. Falcons, Snowy Owls, and other predators moving along the barrier islands would have little reason to be attracted to this place.

The timing of the birds’ departure and return may be related to changes in air temperature and its effect on ice formation. On nights when the air temperature is below freezing (as it was last night), I have frequently observed the formation of new ice on the surface of the few spaces of open water in the sea ice directly adjacent to shore. This newly formed ice melts in the morning as air temperatures rise. Nocturnal formation of new ice in the waters adjacent to the pack ice reduces the amount of open water available for guillemots to dive for the prey.

This temporary daily reduction in foraging area could be expected to have been pronounced during the Last Glacial Maximum when air temperatures were lower and the ancestors of the Cooper Island guillemots occupied an Arctic refugium. The current pattern of colony attendance for the Cooper Island colony – foraging during the warmest part of the day and attending the breeding colony at night – could have evolved as a way of maximizing the amount of open water available for guillemots.

The large expanse of shorefast ice north of the island this year is persisting later than expected compared to recent years. While the nearshore ice may now be forcing the Cooper Island guillemots to fly further in search of prey, it could benefit the colony later this summer should ice remain in the nearshore close to the colony. In recent years a lack of sea ice when the guillemots are feeding young resulted in increased nestling mortality as higher sea surface temperatures reduced the availability of Arctic Cod, the guillemots’ preferred prey.

Should this year’s nearshore ice break up slowly over the next month, Arctic Cod could remain in the guillemots’ foraging range and allow increased chick growth and fledging success. The latter is urgently needed for the colony to reduce its current population decline. First eggs will be hatching in about two weeks and our daily weighing of nestlings and prey observations should demonstrate how much this year’s persistent sea ice has affected the guillemots’ nearshore environment.


This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.


Read more

Arctic Sea Ice a Major Determinant in Mandt’s Black Guillemot Movement and Distribution During Non-Breeding Season by G. J. Divoky, D. C. Douglas, I. J. Stenhouse

All About Sea Ice by National Snow and Ice Data Center

Summertime and the Sea Ice is Leaving by Jenny Woodman

Take the A-Train to the Arctic by Jenny Woodman

 

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Categories
Arctic Change

Long-term Decline Accelerates in Arctic

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George collecting data at nesting case in 2015; the cases were added once polar bears became regular visits on the island. Image Credit: George Divoky

The Cooper Island Black Guillemot colony experiences a major decrease in breeding pairs as long-term decline accelerates.

As of July 6, egg laying ended at the Cooper Island colony and the number of breeding pairs is the lowest it has been in four decades. Only 50 guillemot pairs have laid eggs, down from 85 pairs last year, 100 pairs in 2016 and 200 pairs in the late 1980s.

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Cooper Island breeding pairs over the years; it is important to note that the number of available sites has not decreased as the population has decreased, meaning some environmental factor has likely been decreasing the population. Image Credit: Jenny Woodman

A primary reason for the decline was increased overwinter mortality, with almost one third of the last year’s breeders failing to return to the colony. The long-term average for overwinter mortality is ten percent. Also contributing to the decline was a paucity of recruits to occupy the vacancies created by the mortality. Many of this year’s pairs are composed of two birds that lost mates over the winter. All recruitment that did occur were of birds that had fledged from Cooper Island. Immigrants used to constitute the majority of birds recruited into the breeding population.

A potential reason for the high mortality is the lack of sea ice in the area traditionally occupied by Cooper Island guillemots in winter. The unprecedented lack of sea ice over the Bering Sea shelf likely forced birds to occupy the ice edge in the Arctic Basin north of the Bering Strait, where prey resources may not be as abundant.

The 15 geolocators recently removed from returning birds will allow determination of the winter distribution.

The number of breeding pairs also declined due to the number of pairs maintaining nest sites but failing to lay eggs. Nonbreeding by experienced birds and established pairs has been extremely rare on Cooper Island but this year there are 20 such pairs. The presence of such birds, unable to initiate clutches after occupying a nest site, is an indication that overwinter or spring conditions caused both a decrease in the condition of returning birds as well as increased mortality.

Eggs will begin hatching in the third week of July and one has to hope fledging success will be high.


This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island website.


Read more

The Earliest Year by George Divoky

Summertime and the Sea Ice is Leaving by Jenny Woodman

In the Arctic, the Old Ice Is Disappearing by Jeremy White and Kendra Pierre-Louis (2018)

Sea Ice by Michon Scott and Kathryn Hansen for NASA Earth Observatory

Categories
Arctic Change

Work Worth Doing

G. Divoky at BG-1 1972
George Divoky in the field at the first Black Guillemot nest site discovered on Cooper Island in 1972. Image Credit: George Divoky

The Cooper Island Black Guillemot study was recently mentioned in an Associated Press story by Seth Borenstein about researchers who “accidentally” began studying climate change. A number of scientists measuring a biological phenomenon have encountered unanticipated effects from climate change and understood those effects were more important, both biologically and politically, than what originally motivated them to initiate their research. The 44-year Cooper Island study has undergone a number of changes before its current focus on assessing the decadal effects of Arctic warming on seabirds.

When I first landed on Cooper Island in 1975, I had no intention of studying climate change or global warming.

Neither the globe nor the Arctic had warmed in the decades immediately preceding the start of my study. Research at the Cooper Island Black Guillemot colony started as part of a large federal program assessing Alaska’s then largely unknown marine ecosystems in anticipation of leasing offshore waters for oil development. Cooper Island was the furthest north of many seabird colonies in coastal Alaska where biologists documented the extent and basic biology of the state’s seabird resources in the late 1970s. When that program ended in 1981, due to a change of administrations and a less urgent need to move forward with offshore drilling, it had provided sufficient information for the drafting of environmental impact statements.

In 1982, lacking federal funding, and possibly more importantly logistical support, I made the decision to return to Cooper Island to continue the Black Guillemot study. I had developed a real attachment to northern Alaska with its field seasons of 24 hours of daylight and sea ice always visible just offshore. Through annual banding of breeding birds and their nestlings in the late 1970s, I had developed a population of largely known-history and known-age seabirds. I was initially drawn to the study of seabirds having read the works of British ornithologists conducting multi-year studies at a single colony and documenting the life histories of individual birds. Such work is beyond the scope and timeframe of pre-development environmental assessments and of federal agencies, with their frequently shifting agendas.

Only in the third decade of research was there an indication that increasing atmospheric temperatures were affecting the Black Guillemot colony. Earlier snowmelt in the 1990s allowed earlier initiation of breeding. Climate change impacts rapidly increased in the 21st Century as decreasing sea ice and increasing sea surface temperatures reduced the guillemots’ preferred prey and greatly reduced breeding success. The least nuanced sign of Arctic warming, polar bears stranded on the island approaching our field camp, began in 2002 and this will certainly occur again this summer.

While monitoring the effects of climate change will continue to be the focus of the work, the study is now proceeding in ways never anticipated in 1975. Since 2011, we have deployed biologgers on the bands of guillemots to measure diving behavior during breeding and location and activity of birds during the nonbreeding season. That work is being continued and analyzed as part of the Sentinels of Sea Ice (SENSEI) project, which this fall will have our collaborators from France’s National Center for Scientific Research (CNRS) hiring a post-doc to examine our demographic database.

Vicki Friesen of Queen’s University in Kingston, Ontario has a graduate student, Drew Sauve, examining the genetics of individual guillemots and the heritability of the metrics we have obtained on breeding biology.  Drew recently completed a master’s degree on the heritability of timing of egg laying and is beginning a doctoral program utilizing the Cooper Island colony and database. He will be joining me on the island later this month to gather additional genetic material.

As I walked around the colony this past week in this 44th year of the study, determining nest ownership and dates of egg laying, it is extremely satisfying to know the data is part of a data set spanning six generations of guillemots and can provide unparalleled insights into the biology of an Arctic seabird experiencing a rapidly changing environment.


This field report is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island.


Read more

Alaska’s North Slope Snow-Free Season is Lengthening from University of Colorado Boulder

Exit, Pursued by Bear by George Divoky

Categories
Arctic Change

Cooper Island’s 44th Field Season Underway

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George Divoky’s 2018 arrival on Cooper Island for his 44th field season. Image Credit: Craig George

June 19, 2018, after several weather-related delays, Search and Rescue pilots transported George and his gear to Cooper Island. His cabin is packed floor to ceiling with supplies stored over the winter, and he arrived with 800 pounds of equipment to support his 44th season studying Arctic seabirds.

While the Arctic has experienced back-to-back record-breaking years of warming, Utqiaġvik and North Slope of Alaska encountered unusually cold weather and snowfall this spring. According to George, he hasn’t seen conditions like this since the 1970s.

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The most recent image of NOAA’s Earth System Research Laboratory (ESRL) Barrow Observatory show snow accumulation in the middle of June 2018. Image Credit: NOAA ESRL

He predicts the late snowmelt will make this season particularly difficult for his Black Guillemots, who are already struggling to adapt to an ecosystem imperiled by climate change.

The delayed breeding season means the parents will have to fly farther to reach retreating sea ice in order find food that is ideal for guillemot chicks.

The longer distance means the parents expend more energy, which is a precious commodity for seabirds. In Far from Land, Michael Brooke writes, “Natural selection will favour individuals which do not imperil their own long-term chances of survival by recklessly over-investing in any single year’s offspring.” Brooke adds that it is better to forgo a single year’s offspring in the hopes of future generations of potential chicks, because seabirds like albatross and guillemots tend to lay small clutches of eggs. The Cooper Island birds typically lay two eggs each year.

Based on previous year’s data collected via geolocators George uses to track the birds, he thinks they’ve been in Nuvuk for the last month. Also known as Point Barrow, this headland is about nine miles east of Utqiaġvik. The guillemots are waiting for the snow to melt, George says.

“Snowmelt at NOAA’s Barrow Observatory typically occurs about a week before egg laying,”  George noted on social media. “Female guillemots don’t ovulate until snowmelt allows access to the nest cavity.”

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George waves goodbye from Cooper Island on June 19. Image Credit: Craig George

Once George sets up camp — which is no small feat alone in freezing temperatures — he’ll be sending us regular updates via satellite, which we will be sharing here. Follow us on Facebook, Twitter, and Instagram for the latest news and Arctic insights.


This story is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island.


Read More

NOAA’s Earth System Research Laboratory (ESRL) Global Monitoring Division, Barrow, Alaska Observatory

Looking For Signs of Global Warming, They’re All Around You by Seth Borenstein

Trying To Stay Optimistic In A Seabird Colony That Is Half Full – When It Is Really Half Empty by George Divoky

Categories
Arctic Change

Take the A-Train to the Arctic

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This Aqua satellite was launched in 2004; it collects about 89 Gigabytes of data per day about elements of the Earth’s water cycle — including water in liquid, solid, and vapor form. Image Credit: NASA’s Earth Observing System

In the Arctic, much depends on ice. Pack ice. Drift ice. Old ice. New ice. For some wildlife, ice provides safe haven from predators and for others, it offers access to prey. For humans, many of whom are living in isolated coastal communities with no roads in or out, ice is everything.

Sailors and explorers have kept sporadic records about ice conditions dating back thousands of years, but only since 1979, with the launch of Earth observing satellites, have streams of near-constant information about Arctic sea ice been available. Using images and observations captured daily, scientists are able to measure ice thickness, area of coverage, and seasonal fluctuations in the advance and retreat of ice coverage.

Real-time sea ice images and data are vital for the safety of researchers like George Divoky and for people in Arctic communities who depend on ice for subsistence hunting and fishing. Anthony Fischbach is a wildlife biologist for the United States Geological Survey (USGS) in the Alaska Science Center Walrus Research Program, where he has worked since 1994. Fishbach delivers a daily “Ice Mail” to just over 100 people interested in up-to-date information on Arctic sea ice. Subscribers include Divoky, scientists in Russia, and remote Inuit communities who may not have easy access to internet connections capable of retrieving large amounts of data.

“The main niche I’m trying to fill is a way to get meaningful sea ice imagery and charts in the palm of your hand or on the deck of a ship where you’ve got really minimal bandwidth,” said Fischbach. “If you’re in a remote community that has 2G cell phone connection or if you’re on an Iridium-linked vessel, the existing ways of accessing the data just don’t meet the need.”

He described his own experiences of working in Arctic coastal communities or being on board a retrofitted crabber, “We just struggled to get the data through the existing methods and we couldn’t get all the data we wanted.”

Today, Fischbach relies heavily on two satellites we’ll be following closely this summer — Aqua and Terra. Both are part of NASA’s Afternoon Constellation or A-Train, which is a convoy of satellites operated by NASA and international partners. The satellites travel together, completing a polar orbit twice a day; because of the Earth’s rotation, a polar orbit means that the satellites will observe the entirety of the planet’s surface every one to two days.

The A-Train crosses the equator at about 1:30 a.m and 1:30 p.m.; the Terra satellite passes the equator in the early morning, Aqua in the afternoon. This timing and repetition allows scientists to generate cloud-free images and to study how temperatures over land and water change from day to day.

By flying satellites loaded with a host of Earth-observing instruments in a formation, scientists are able to gather a great deal of meaningful data. According to NASA, flying in concert “allows for synergy between the missions—synergy means that more information about the condition of the Earth is obtained from the combined observations than would be possible from the sum of the observations taken independently.”

While each satellite is tasked with different mission objectives, the data from individual instruments can be combined to paint a more vivid and informative picture of the Earth’s climate and atmospheric systems.

This visualization shows the orbits of NASA-related near-Earth science missions that are considered operational as of March 2017. Video Credit: Greg Shirah for NASA Visualization Studio

A key instrument on board Aqua and Terra is a moderate resolution imaging spectroradiometer, or MODIS for short, which is capable of of observing across 36 spectral bands or wavelengths at different resolutions (250, 500, and 1000 meters). (A complete technical profile of this instrument and the data it provides can be found here.)

MODIS is an integral instrument for studying the ocean, because it aids in the creation of ocean color maps. Ocean color reveals much about phytoplankton productivity, which, according to NASA, forms the basis of the ocean’s food chain and plays a big part in carbon storage and movement. MODIS also allows for detailed maps of sea surface temperatures, which are known to influence weather patterns. Since MODIS is able to study water in liquid, solid or gas form, the instrument aids measurement of snow and sea ice and how much solar energy is being absorbed or reflected back to space.

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This ice map for May 24, 2018, generated by United States Geological Survey (USGS) in Alaska, combines MODIS images from Aqua and Terra with National Ice Center data. Image Credit: Anthony Fischbach for USGS

Fischbach explains that the images in his daily emails (seen above) are processed with false color so you can distinguish the white of the clouds with the white of the sea ice; sea ice is aqua-colored and the clouds appear white. The images show detail down to 250 meter resolution, meaning you can clearly see objects that are 250 meters or 820 feet wide.

To people living and working in the the Arctic, these sea ice data could be comparable to monitoring hazards on roadways in the lower 48, because the ice and water provide access for both transportation and food.

The ice is moving constantly, which creates precarious decision-making choices in remote regions without the right information. With several days of ice data in hand, people in the field  like Fishbach and Divoky can make better choices.

“I’d really like to know as much as I can about how the ice is moving. Is there more ice coming this way? Is it going to be congesting? Is it going to be opening up?” he asks. “You know, do I launch boat out in to the ice —  the shifting seascape — where I could get pinned in and trapped and not make it home?”


This story is part of an ongoing series titled Arctic Change centered around George Divoky’s 44th field season studying Black Guillemots, sea ice, and climate change on a remote Arctic island off the coast of Alaska. To donate and support Divoky’s work on Cooper Island, visit the Friends of Cooper Island.


Read More

Arctic Sea Ice By NASA Earth Observatory

50 Years of Earth Observation by European Space Agency

Monitoring Sea Ice by NASA Earth Observatory