As Alaska Glaciers Shrink, Salmon Populations May Also Decline

A view of the Kenai River (Source: Frank Kovalchek/Wikimedia Commons).

Alaska is experiencing some of the most rapid changes to glaciers and ice fields on Earth. Global warming is causing drier summers and wetter autumns, and changing the landscape through the melting of glaciers and the loss of wetlands and wildfires. The salmon population in the area will also likely be impacted from these environmental changes: some will benefit from the changes, while some will be negatively impacted. A new study in Fisheries Journal investigates the region’s Kenai River and the future climate change impacts on healthy salmon populations.

Salmon in the Kenai River

The Gulf of Alaska region produces a third of the world’s wild salmon; however, the Chinook Salmon (O. tshawytscha) population has declined. Environmental changes are likely to impact future populations. The Kenai River supports world-famous fisheries in the region and exemplifies the high social, economic, and ecological value of wild salmon as well as the complex changes they face. Its yield faces a serious threat with the area strongly influenced by glaciers that are losing mass. The Chinook Salmon may not recover, and the populations that are declining threaten the livelihoods of the dependent fishing communities. The fishing communities are diverse and include indigenous, sport and commercial fishers. The authors of the study wrote, “Kenai River salmon support several of Alaska’s largest recreational salmon fisheries, major commercial gill-net and personal-use dip-net fisheries, as well as small-scale subsistence and educational fisheries.”

The Salmon Life Cycle

Chinook Salmon (fry) (Source: USFWS Photo by Roger Tabor/Flickr).

Chinook salmon is an anadromous fish species. Individuals hatch in freshwater rivers, then the young fish swim out to the ocean to grow and mature, and later return up the river to spawn and then die. The cycle begins as the female lays eggs in the gravel on the bottom of the river (this nest is called redd). The redd is then fertilized by a male, and the eggs remain in the gravel throughout the winter as the embryos develop. As the eggs hatch in the spring, alevins emerge. Alevins are tiny fish with the yolk sac of the egg attached to their bellies. After they have consumed the yolk sac and grown larger, they emerge from the gravel and are then considered fry. Fry can spend up to a year or more in their natal stream. After, the fry begin to migrate downstream toward the ocean.

Eran Hood, professor of Environmental Science & Geography at the University of Alaska Southeast, told GlacierHub that glaciers provide an important source of streamflow during the late summer salmon spawning season. In addition, Hood added, “glaciers are important for moderating stream temperatures during warm periods when spawning salmon can become metabolically stressed by warm water temperatures and associated low levels of dissolved oxygen.”

Glacial Rivers

Glacially-fed rivers respond to weather and climate differently than non-glacial rivers. During hot and dry summers, the water in a typical non-glacial river will warm up and streamflows will drop. However, the same summer conditions will cause glaciers to melt faster and lead to more cold water input into glacial rivers. In Alaska, many important salmon rivers are fed by a mix of glacial and non-glacial streams. If one of the streams suffers from drought conditions, there is a chance that another stream in the same section of the watershed has a lot of deep and cold water. Schoen explained to GlacierHub, “This habitat diversity helps to stabilize salmon runs on a large scale, and lessen the risks of boom-and-bust dynamics in our fisheries.”

Jeffrey A. Falke, professor of fisheries and assistant leader at the Institute of Arctic Biology at the University of Alaska Fairbanks, explained to GlacierHub that the major concerns from a freshwater perspective are changing patterns in the timing and magnitude of stream flows, and increasing water temperatures. “Salmon are at the margin of their range in much of Alaska so the latter may be less of an immediate concern. However, changes to flows have already occurred and are projected to increase into the future,” he said.

Falke told GlacierHub that the glacial rivers are an important habitat for multiple species of salmon across Alaska. The river bottoms and banks are also important habitats for the fish. Glacier loss causes changes to the hydrology of these systems, which includes both the rivers and the habitats that they support. Climate change could make the glacier river systems more similar to surface water/snowmelt runoff systems, which would therefore reduce the diversity of habitats. By reducing or removing the habitats favored by specific salmon species and by specific stocks (sub-populations) within the species, it would also reduce the salmon biodiversity. Falke further stated, “I’m not sure we can do anything about glacial loss, but continuing to work to ensure that there is a broad array of intact habitats in other areas will be key.”

Perspective rendering showing retreat of the Skilak Glacier, a major source of glacial runoff to the Kenai River. Colored lines indicate ice extent for 1952, 1978, and 2013 derived from aerial photographs (Source: Future of Pacific Salmon in the Face of Environmental Change).

The author of the study, Erik Schoen, a postdoctoral fellow at Alaska Cooperative Fish and Wildlife Research Unit at the University of Alaska Fairbanks, told GlacierHub that climatic and landscape changes influence salmon ecosystems. These diverse ecosystems are large, varied, and interact with glaciers in different ways,. Thus, the changes will not necessarily be all negative or all positive. “Some of the salmon runs that Alaskans have relied on for generations are probably going to decline, but other runs may become more productive, and we have a chance to shape that with strong habitat protections,” he said.

Changing Environmental Factors

The authors of the study conclude that salmon rivers in this region face a complex set of climate-driven changes, including warmer summer stream temperatures, glacier retreat, and increasing streamflows during fall and winter when developing embryos are vulnerable to more rapid flow even in relatively sheltered areas where females deposit their eggs.

The overall results of climate change are likely going to cause winners and losers, the authors note. There are five species of Pacific salmon, and they each use a range of different life-history strategies and habitat types, so are likely to respond in different ways. Schoen explained to GlacierHub that hotter, drier summers will expose salmon to low oxygen levels which can cause die-offs. “This is a big concern in small, lowland streams, but less so in streams with a cooling glacial or snow-melt influence. Warmer winters are causing more rain-on-snow events, which can cause floods that kill salmon eggs in the streambed,” he said. It’s important to mention that some streams are more likely to be affected than others, he added. A positive outcome from glacier retreat is that it allows salmon to colonize new streams and lakes. Longer ice-free growing seasons allow the juvenile salmon to grow larger in certain habitats.

Economic Impacts

Schoen explained the economic importance of salmon in the region: “Salmon fishing is one of the main pillars of the Kenai Peninsula’s economy, and an important part of the overall Alaskan economy. This includes commercial fishing (and support industries) and recreational fishing, which is a major driver of the tourism industry.”

The study can help build resilience toward a changing climate. Schoen told GlacierHub, “Our goal was to highlight the rapid changes happening in the Gulf of Alaska region and explain what this means for salmon and the people who depend on them.” There is a large amount of research documenting these changes; however, the majority does not always allow for an easy understanding of the big picture. “We wanted to make the science more accessible to the general public, policy makers, and scientists in other fields,” Schoen added.

Increased Resilience

A Chinook salmon or Oncorhynchus tshawytscha (Source: Alaska Department of Fish and Game).

Falke told GlacierHub that the best way to ensure robust salmon populations is to maintain and promote diverse habitats and life histories. “Luckily in Alaska there are mostly intact habitats, and the example of the Bristol Bay sockeye salmon fishery is the best to highlight how diversity equals both ecological and economic resilience,” Falke added.

Schoen explained to GlacierHub that prior research has shown that fishing communities can stabilize their revenue streams by diversifying their catch to include different fish species and stocks. A stock of fish is a population within a species that migrates together, breeds together, and is genetically distinct; one species will have a number of stocks, some of which could respond to climate impacts more favorably than others. However, many fishing communities have adopted strategies that are the reverse, concentrating their efforts on fewer stocks. “Diversifying the fishing sector (and overall economy) is an important goal to increase the resilience of Alaskan communities to rapid and unpredictable climate change,” Schoen further explained.

Hood told GlacierHub about the critical importance of more holistic research, which can provide an understanding of how glacier change is impacting the structure and function of food webs downstream rivers and estuaries. “This information will allow us to better project future impacts and understand how ecosystems services such as fisheries and tourism opportunities may change in the future,” Hood added.

This research show the complex effects of glacier retreat on salmon populations and the humans that depend on them. Though most salmon species face less favorable conditions in most of their range, some species are hit harder than others. And the impacts on the habitats, though generally negative, are less severe in some areas than others, and some new habitats are being created by glacier retreat. This article marks a major advance in this complex system, a topic of great importance for the fishing communities— indigenous, sport and commercial fishers.

Glacier Retreat and Trace-Metal Contamination in Peru

The Cordillera Blanca, the largest glacial area in the tropics (Source: Richard Doker/Flickr).

The Cordillera Blanca is the most glacierized area in the tropics, but in the last 30 years the region has lost over 25 percent of its glacier area. A consequence of this glacier retreat has been higher concentrations of heavy metals downstream, which have created serious water contamination issues for indigenous communities living nearby the shrinking glaciers. A recent study led by Alexandre Guittard, Michel Baraër, Jeffrey M. McKenzie and others provided a comprehensive assessment of the extent of trace-metal contamination across the Rio Santa basin, one of the largest and most important rivers in the Cordillera Blanca range.

Part of the glacier runoff from the Cordillera Blanca that feeds the Rio Santa (Source: Esmée Winnubst/Flickr).

About 300 miles northeast of the capital city of Lima, the glacier-fed Santa river is located in the Ancash Region of Peru, flowing north between the glacierized Blanca and the non-glacierized Negra mountain ranges, winding west through the Cañon del Pato before discharging into the Pacific Ocean. Since the 1940s, the region has experienced population growth and increased economic activities, greatly intensifying water demand.

“For two decades we have been hearing about shrinking mountain glaciers and the impacts on downstream water supplies. But the vast majority of the research in glacierized basins so far has been on the quantity of water coming out of the glaciers, not the quality of that water,” environmental historian Mark Carey, one of the authors of the study, explained to GlacierHub. “Studies must also take seriously the issues of intensifying water contamination and risk levels for communities living downstream from shrinking glaciers.”

But how does glacier retreat result in trace metal contamination? Essentially, there are two opposing theories, according to lead author Michel Baraër. The first theory is that glacier retreat uncovers bedrock rich in pyrite that oxidizes when uncovered, acidifying the water and facilitating the release of trace metals in water, he told GlacierHub.

The second theory deals with glacier retreat and its impact on the physical weathering of the bedrock, which decreases in intensity. “There are therefore less fresh particles released in water bodies and therefore less trace metals,” he said. To break down the two theories, the authors pinpoint anthropogenic sources (i.e. active mining) to be a major source of the trace metal contamination. Thus, even if the two theories counteract one another, scientists consider the anthropogenic influence of industrial mining, as noted throughout the study, to be a much stronger contributor to the water contamination.

This map demonstrates the breakdown of trace-metal contamination across the Rio Santa Basin (Source: Guittard et al.).

According to the study, “the findings indicate that contamination levels in some areas of the watershed could potentially represent a threat to the health of humans or ecosystems.” Water quality has been a major issue in recent years, and the contamination of arsenic and manganese as found could have devastating health and ecological impacts on the quality of life in the Rio Santa basin.

Even if mining activities are shut down, contamination would continue to be problematic under climate change if the first theory— that glacier retreat exacerbates the oxidation process— outweighs the second that states it slows the release. There is already concern about another health risk: disease-causing organisms that may be lying dormant in ice. They might become more active as they thaw. If that is the case, communities and scientists must keep a careful eye on receding glaciers across the world to see what health impacts may arise when the ice melts.

Cooperation in the Face of Glacier Retreat: The Plants’ Story

As new areas become exposed by glacier retreat, plants begin to colonize them. Do the different species support or compete with one another? A recent study in the Journal of Vegetation Science follows the interactions of the circumpolar moss Silene acaulis, a type of cushion plant, with other secondary species like the buckwheat Bistorta vivipara in a southern Norway glacier, which has been retreating.

Five transact sites chosen for the study (Source: Klanderud et al.)

To answer this question, Kari Klanderud and her colleagues from the Norwegian University of Life Sciences demarcated five transact areas that were of increasing distance from the Midtdalsbreen glacier. Areas further away from the glacier represent better environmental conditions for growth as abiotic stress decreases, showing an environment gradient. The further from the glacier, the longer the area has been exposed, resulting in more advanced colonization. The abundance of buckwheat and the number of species of secondary plants within and outside of cushion plants were analyzed by conscientiously photographing the plant species in those areas. Soil temperature, moisture, organic content and pH measurements were also taken to examine if cushion plants modify the abiotic environment.

“We chose to work on S. Acaulis because it is common in alpine and arctic areas worldwide,” lead author Klanderud told Glacierhub. The cushion plant, a fascinating species that can survive in harsh climates, is commonly found in exposed habitats such as alpine tundra and places of cold-air drainage such as glacial moraines. It resembles a large green mat that can grow up to three meters in diameter. As a pioneer species in alpine habitats, the cushion plant nobly optimizes environmental conditions to facilitate growth of secondary plants like the buckwheat. This kickstarts the process of primary succession. These ungrateful secondary plants will continue to shamelessly grow, dominate and ultimately replace their pioneers so that eventually a community with larger species variety is achieved.

Cushion Plant, Silene acaulis which is also known as Moss Campion (Source: Wikipedia Commons)

Why is the cushion plant able to survive the harsh conditions in the first place? Lawrence Walker, a professor at the University of Nevada who specializes in plant ecology, told Glacierhub, “Their compact growth form preserves heat, which leads to a longer growing season and minimal frost damage during summer months. The cushion growth form also avoids breakage of stems from strong winds.” The benefits of being compact is not only self-serving, its structure also facilitates secondary plants’ growth and survival by buffering extreme soil temperatures. “Even pollinating insects may find refuge in the cushion,” says Walker.

In an environment with limited space and resources for growth, it is every plant for itself. The cushion plant allows other plants to grow within them and in turn compete for nutrients. There must be a threshold for its altruism if the cushion plant wants to survive in the face of the buckwheat and other secondary plants. As Walker explains, “It is common that nurse plants (ones providing protection for small individuals of other plants) can later be outcompeted by the plant that they nursed.”

Must the cushion plant really engage in negative interactions to impede the growth of its ‘child’, the buckwheat to survive? Biologists have discovered that relations of plants vary depending on the level of stress. Coined the stress-gradient hypothesis, this means that competition between plant species is strongest during favorable environmental conditions, but these species will support one another when the going gets tough. With decreasing biotic stress, plant interactions tend to shift from facilitative to competitive.

Buckwheat, Bistorta vivipara (Source: Pinterest).

Indeed, for sites close to the glacier that represent the harshest abiotic conditions, the buckwheat performed better, as shown by bigger leaves when it is grown between the stems of the cushion plant. These sites are characterized by fewer organisms which accentuates the harsh conditions. Soils closer to the glacier contain less organic matter due to a shorter lifespan of the ecosystem present. The plants also lack support and shelter from one another to moderate the environmental conditions. “The very dense and dome-shaped cushion modifies the microclimate and thus the growing condition for other plants,” Klanderud explained.

There was limited difference in buckwheat growth performance in more favourable environments further from the glacier. In this case, the cushions support the theory above. However, during conditions of low abiotic stress, it still has a “conscience,” shifting only from facilitative to neutral interactions instead of negatively affecting the performance of the buckwheat. In terms of secondary plant species diversity, a trend of higher species richness was observed within the cushions across all the sites, with cushions buffering extreme soil temperatures as the main abiotic reason.

While glacier retreat often has a negative connotation, it can also represent new opportunities for plants and other species to build communities in newfound lands. Nonetheless, one thing is for sure – survival is key, prompting cooperation when needed but also knowing when to draw the line, just like humans.

Let it Snow… and Save a Glacier

Snow machines would be used to cover a section of the glacier (Source: Hans/Creative Commons).

News about shrinking glaciers is not uncommon, but have you ever heard of regrowing one artificially? That is exactly what a team of researchers intends to do: use snow machines, also known as Schneekanonen (snow-cannons) in German, to save Morteratsch Glacier in the Swiss Alps.

Felix Keller, a glaciologist at the Academia Engiadina in Switzerland, and Johannes Oerlemans, director of the Institute for Marine and Atmospheric Research at Utrecht University in the Netherlands, will use snow machines to slow down, or even reverse, the retreat of the glacier as announced at the annual meeting of the European Geosciences Union in Vienna, Austria, on April 27th.

Morteratsch, located in Pontresina in the canton of Graubünden, is the third largest glacier in the Eastern Alps. It is also one of the most easily accessible glaciers: a 50-minute walk from Morteratsch train station along a hiking trail leads visitors directly to the glacier tongue. This makes it a popular tourist attraction that contributes to the economy of the region. However, the glacier has been shrinking rapidly because of climate change, retreating about 2.5 kilometers over the last 150 years.

Morteratsch Glacier is easily accessible by a foot traill (Source: Simo Räsänen/Creative Commons).

The plan to save the glacier using snow machines was inspired by the successful use of white fleece coverings to slow down the retreat of the nearby Diavolezzafirn Glacier. This method has been applied over the past 10 years to help the glacier grow by up to 8 meters in length. Locals reached out to Oerlemans and Keller, who have done prior research in the region, to try to save Morteratsch in a similar manner, except the latest plan involves covering sections of the glacier with snow to reduce melting during the summer.

The municipality of Pontresina, in whose territory the glacier is situated, is trying to position itself as a village at the forefront of climate change issues,” Daniel Farinotti, a glaciologist at both Swiss Federal Institute of Technology (ETH) in Zurich and the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), shared in an interview with GlacierHub.

Pontresina and Morteratsch glacier can be reached by train (Source: Creative Commons).

A layer of snow will protect the ice from incoming radiation, which would warm up the glacier. A secondary and smaller effect would be to protect the ice from overlying air, which could be above freezing. Models used by the researchers suggest that a thin layer of snow covering under one square kilometer at the top of the glacier would be enough to protect the glacier. Oerlemans also estimates that this could help the glacier regain 800 meters of length in two decades.

This plan would involve the use of 4,000 snow machines, which produce snow from water and pressurized air. They will be supplied with meltwater from a nearby glacier, which addresses a key concern: “If we want to do it on a larger scale, the main challenge will be the availability and transportation of meltwater onto the glacier,” Oerlemans shared with GlacierHub.

Not everyone is convinced that the plan will work. “I am still a little skeptical that the technical problems are solved and would like to see answers to some questions,” Greg Greenwood, executive director of the Mountain Research Initiative, shared with GlacierHub. These questions include exactly where the snow will be deposited, financial and environmental costs, and a comparison with other technical options.

Oerlemans and Keller are currently conducting a pilot project costing $100,000 at the foot of Diavolezzafirn glacier, also in Switzerland. 13 feet of snow will be blown over the 1,300-square-foot glacier by the end of the month. If it works, they hope that the Swiss government will fund the Morteratsch project, which will cost several million Swiss Francs.

We will try to get the glacier through the summer with one snow machine. We can produce snow only 5 percent of the time, but it could be sufficient as making snow is faster than the melting process,” Oerlemans explained.

The glacier is part of Switzerland’s longest downhill glacier ski run (Source: Terje Sollie/Creative Commons).

Morteratsch glacier is part of Switzerland’s longest downhill glacier ski run, making it part of a popular ski destination. However, the project is also being attempted to protect water supplies, as meltwater is often an important source of water in mountainous regions.

Costs are a concern, particularly those related to “how much energy they would require per unit of time,” Farinotti shared. “This would be one of the key numbers needed to assess whether the project is sensible or not,” he added. Oerlemans also explained that the need to cover a large area for many years will contribute to significant costs.

Snow machines use electricity to make snow from water. Although Switzerland produces about 65 percent of its electricity from hydropower, it still relies on fossil fuels for a proportion of its electricity. As such, energy use is also an important consideration in relation to the indirect production of greenhouse gases.

It is unlikely that this plan can  provide a solution to glacier recession due to the high costs of the endeavor and the difficulties of up-scaling it. However, it could send very compelling messages depending on how it is communicated. “The initiative could be very powerful in conveying the message that even partially offsetting climate change impacts will need tremendous efforts.” Farinotti said. “The project could be powerful in putting a price on this kind of initiative.”

Check out other geoengineering projects, such as this one to refreeze the Arctic or an artificial glacier built to help save some of Ladakh’s winter water for the summertime.

Glacier Retreat Exposes New Breeding Ground for Kelp Gulls in Antarctica

Glacier retreat caused by anthropogenic climate change is often in the news because of its impacts on sea level rise and shrinking habitats. However, a recent study published by Lee et al. in the Journal of Ethology has found that glacier retreat on King George Island could have a positive impact on kelp gulls, exposing new ground with suitable breeding sites.

Kelp gulls have a large range in the southern Hemisphere (Source: Yuri Hutflesz / Creative Commons).
Kelp gulls have a large range in the southern Hemisphere (Source: Yuri Hutflesz/Creative Commons).

The kelp gull, Larus dominicanus, breeds on coasts and islands throughout the Southern Hemisphere, as detailed on the IUCN Red List. It has a large range, from subantarctic islands and the Antarctic peninsula to coastal areas of Australia, Africa and South America. Breeding occurs between September and January, with nests usually built on bare soil, rocks or mud in well-vegetated sites.

King George Island, the largest of the South Shetland islands, is part of the kelp gull’s range. It can be found off the coast of the Antarctic peninsula and is a nesting ground for seabird species during the summer months. Numerous research stations are located on the island, and its coasts are home to a variety of wildlife, such as elephant and leopard seals, and Adelie and Gentoo penguins.

A map of Barton Peninsula on King George Island (Source: NOAA).
A map of Barton Peninsula on King George Island (Source: NOAA).

Research has shown that breeding nests of kelp gulls have been recorded in ice-free areas of King George Island since the 1970s. Studies of Gentoo penguin populations  also suggest that rapid glacier retreat could give species that favor ice-free environments a chance to expand their habitats. As such, Lee et al. used a combination of satellite photographs and field observations of kelp gull nests in newly exposed locations to study possible correlations between glacier retreat and nest distribution in the Barton Peninsula on King George Island.

Based on eight different satellite images, Lee et al. determined that glaciers on the Barton Peninsula have retreated 200-300m from the coast since 1989, exposing an area of approximately 96,000 square kilometers. Within this area, they found up to 34 kelp gull breeding nests between 2012 and 2016, along with evidence that kelp gulls have been breeding on newly exposed ground for decades.

A map of the study site showing the extent of glacier retreat and locations of kelp gull nests (Source: Lee et al.).
A map of the study site showing the extent of glacier retreat and locations of kelp gull nests (Source: Lee et al.).

As the glaciers on the Barton peninsula retreat inland, moraine surfaces made up of glacial soil and rock debris are left on the coast. Rocks within these moraines provide shelter from harsh Antarctic coastal winds, reducing the stress to the gulls arising from these winds. This makes the exposed areas more attractive for breeding.

Previous studies have suggested that kelp gulls select nest sites in favorable locations with rock and vegetation cover, and kelp gull populations are known to nest in neighboring areas like Potter Peninsula and Admiralty Bay. In this study, kelp gull nests were found between 40-50cm away from the rocks, suggesting that a combination of rocks and vegetation present on the moraines help to create favorable nesting conditions.

The rocky moraines left on the coast by retreating glaciers are suitable breeding ground for kelp gulls (Source: Acaro / Creative Commons).
The rocky moraines left on the coast by retreating glaciers are suitable breeding ground for kelp gulls (Source: Acaro/Creative Commons).

These gulls probably originated from neighboring kelp gull populations, such as those on King George Island or the Nelson Islands. Continued retreat of glaciers on King George Island could expose larger areas of suitable breeding ground, attracting more gulls from neighboring islands and increasing kelp gull populations.

Anthropogenic climate change and glacier retreat have many adverse effects, but research like this sheds light on the ways in which some species might benefit in unexpected ways.

BREAKING: Ryan Zinke Confirmed as Interior Secretary, Talks Glacier Retreat

U.S. Congressman Ryan Zinke of Montana speaking at the 2016 Conservative Political Action Conference in Maryland (source: Gage Skidmore/Creative Commons).
U.S. Congressman Ryan Zinke of Montana at the 2016 Conservative Political Action Conference in Maryland (source: Gage Skidmore/Creative Commons).

It’s official. The Senate voted today to confirm Rep. Ryan Zinke (RMT) as the nation’s next Secretary of the Interior. The strong majority confirmation vote of 68-31 gives Zinke, a Westerner and fourthgeneration Montanan, commanding power over the nation’s most prized public lands and wildlife as well as 70,000 employees, 280,000 volunteers, and a $12 billion annual budget.

The Department of the Interior— a Cabinet-level agency created in 1849 to manage the country’s internal affairs— oversees such critical offices as the National Park Service, U.S. Fish and Wildlife Service, the Bureau of Indian Affairs, and the U.S. Geological Survey, among others.

A former boy scout turned Navy SEAL in the Iraq desert, Zinke grew up 30 minutes outside of Glacier National Park in Montana, an experience he cites as the impetus for his interest and dedication to environmental stewardship. He has promised to “restore trust” in the department and address the $12-billion maintenance backlog in America’s national parks from Alaska to the beaches of Maine.

Republicans hope Zinke will also usher in a “culture of change” to the Interior by repealing many of the Obama administration’s land management policies seen to favor environmentalists over local interests.

Zinke, a Trump administration favorite, was once considered a moderate Republican when it came to environmental and land management issues, siding with Democrats on bipartisan legislation and standing up to fellow Republicans on conservation principles. He challenged Republican colleagues on the transfer of federal lands to the states, for example, speaking out and voting against certain Republican-led proposals. In 2016, he also supported Democrats in calling for full funding and permanent authorization for the Land and Water Conservation Fund in a bipartisan effort. Most recently, in July 2016, Zinke publicly withdrew from the Republican Convention due to the party’s support of federal land transfers to the states.

150 people joined a rally at Senator Wyden’s office in Portland opposed to President-elect Trump’s 'Climate Denial Cabinet' (Source: 350.org/Flickr). https://www.flickr.com/photos/350org/31426067143/in/photolist-QVxoFh-RuZMuZ-pjY1P1-oehSGb-qN2AVJ-ndCjQY-ELPXyq-EXiFgc-rqSFGM-qu6h96-p1ALEN-r9jjK1-oN9qAq-r9qM7B-r9iiRY-rqSHAr-r9jmCj-EUZyBu-DZVtEt-EUZPR7-QTiGxm-QVYmQe-QTiJiq-QxfyAy-QTiMrj-v2c3ey-PT1NEz-PT1NNv-PT1P2g-PT1NTR-Q3iznc-NWbo9m-Qahg9J-PZABAW-NWb8f3-NWb6P7-Qdw8Av-PDB8CN-QdwzU2-DZVL9k-EP7KHe-EXiU6k-EXiMNv-EvbM3h-ELQjbs-Qdwzcv-QagR3h-PDAKCW-QdwbFD-r9qLwt
150 people joined a rally at Senator Wyden’s office in Portland opposed to President-elect Trump’s ‘Climate Denial Cabinet’ (Source: 350.org/Flickr).

At the same time, Zinke is a vocal advocate for oil and gas development on public lands, fracking and coal mining interests, and weaker protection for endangered species and national monuments, among other anti-environmental platforms, earning him a five percent rating from the League of Conservation Voters and an F rating from the National Parks Action Fund. His recent statements, particularly on the issue of climate change, have some scientists and environmentalists deeply concerned.

On the topic, Zinke openly oscillates between acceptance and denial, both of which he displayed during his confirmation hearing before the U.S. Senate Committee on Energy and Natural Resources in January. However, unlike President Trump, who flat out denies climate change, Zinke went on record during the hearing citing glacier retreat as evidence that the planet is warming in a heated exchange with Senator Bernie Sanders (I-VT).

Sanders was the first to challenge Zinke on the issue during the hearing.

“Climate change is very important to issues that the Department of the Interior deals with,” said Sanders. “Is President-elect Trump right? Is climate change a hoax?”

Zinke seemed to have a response prepared for the question, launching into a multi-part answer on what he called the “tenants” of his climate change perspective. These include: one, his recognition that climate is changing, and two, his belief that man is an influence. “That is indisputable,” Zinke said, adding later, “I do not believe it is a hoax.”

Grinnel Glacier in Glacier National Park (Source: Nathan Young/Flickr).
Grinnell Glacier in Glacier National Park (Source: Nathan Young/Flickr).

Zinke offered Glacier National Park as an example of a visible symptom of climate change that he has witnessed personally. “I have seen glaciers over the period of my time recede. As a matter of fact, when my family and I have eaten lunch on Grinnell Glacier, the glacier has receded during lunch,” Zinke said.

This comment prompted chiding from Sen. Angus King (I-ME) later in the proceedings. “I want to thank you for your straightforward admission that climate change is happening, that human activity is contributing to it, and for also the image of the glacier retreating during lunch,” said King. “I am going to add that to my arsenal of climate change anecdotes.”

Sen. Al Franken (D-MN) also weighed on the topic of receding glaciers. “Glacier National Park is going to be… I don’t know, ‘Lake National Park’ or ‘Mountain National Park,'” said Franken. “But it isn’t going to be Glacier National Park in 30 years.”

A view of Grinnel Lake, Glacier National Park (Source: Kelly Marcum/Flickr).
A view of Grinnel Lake, Glacier National Park (Source: Kelly Marcum/Flickr).

Around glaciers and the subject of glacier retreat, at least, the body seemed to find common ground. But when further probed by Sanders on whether climate change is a hoax, Zinke seemed hesitant. “I believe we should be prudent to be prudent,” he said. “That means, I don’t know definitively. There is a lot of debate on both sides of the aisle,” a response that did not sit well with Sanders.

“Well, actually, there is not a whole lot of debate now,” replied Sanders. “The scientific community is virtually unanimous that climate change is real and causing devastating problems.”

After several hours of testimony and questions that touched on diverse topics from wildfires in Tennessee, coal mining in West Virginia, protection of wild horses across the West, and the delisting of the greater sage-grouse, the committee ultimately approved Zinke’s nomination by a 16-6 vote, advancing his nomination to the full Senate. He was well received by the Republican senators on the committee who see in the congressman an ally and fellow Westerner sympathetic to regional concerns; less so by environmentalists and some Democrats who fear Zinke will shepherd the department in the wrong direction, perhaps even into an era of public land privatization from which there is no return.

Republicans see Zinke, who hails from Montana, an ally who understands local interests (Source: Atauri/Creative Commons).
Republicans see Zinke, who hails from Montana, as an ally who understands local interests (Source: Atauri/Creative Commons).

But on this point, Zinke drove a hard line, at least in rhetoric. “I want to be clear on this point. I am absolutely against the transfer or sale of public land,” he said in his testimony. “I can’t be anymore clear.”

He drew attention to his service in the military as an example of his strong backbone. “This is probably one of the reasons why the president elect put a former Navy SEAL in place,” he said. “I don’t yield to pressure. Higher principle, yes. But my job is to advocate for the Department of the Interior to make sure we have the right funds and to be a voice in the room for great public policy.”

But not all Montanans are convinced of Zinke’s ability to lead the Interior Department well.

“I believe that Zinke has at least minimal qualifications to be Secretary of the Interior simply by virtue of coming from a state in which hunting, fishing, hiking and outdoorsmanship are prominent concerns,” said Bill Cox, an economist and Democrat who lives in Montana. “About where he would come down when public lands confront mining companies, oil and gas drillers, and other commercial ambitions, I am much less confident.”

Jamey Loran, a fourth generation Montanan and a certified public accountant who has worked with Native American tribes for the past 15 years, agreed. “It is difficult to pigeon-hole him as a strict environmentalist or anti-regulation proponent. He will almost always do what is in his own political best interest,” he said.  “He brings a very simplistic mindset to complex problems. I have little hope that he will have much success dealing with problems such as climate change. In fact, I have grave concerns that matters will get much worse because ‘quick fixes’ always benefit those with economic interests over future generations or endangered species.”

Ryan Zinke speaking in Montana (Source: Tony Llama/Flickr).
Ryan Zinke speaking in Montana (Source: Tony Llama/Flickr).

Despite negative views like these, Zinke remains quite popular in his home state, recently winning re-election by a 16-percent margin.

“We are happy with Ryan Zinke as our Secretary of the Interior because he was raised in Montana surrounded by the wilderness and environment, which he will manage as opposed to someone who was raised in the city,” said Carl and Cheryl Baldwin, third-generation conservative ranchers from Montana. “We have talked to him personally as our representative in Congress and know his decisions will not hurt or harm our federal lands.”

Jim Martin, a retired home-builder in Montana, and his wife Judy, added that the balance of timber, recreation, ranching and wilderness is important, something that a Westerner like Zinke understands. “He has lived in other sections of the U.S. so as to realize regional problems with the environment,” said the Martins. “He will not let liberals overpower the conservative right.”

Chairwoman Lisa Murkowski (R-AK), who gave the opening statement at the hearing, drew attention to the deep divides along party lines that exist at the end of the Obama administration’s leadership under Secretary Sally Jewell, a former CEO of REI.

“To state that Alaska has had a difficult or tenuous relationship with the outgoing administration is probably more than an understatement,” said Murkowski. “Instead of seeing us as the State of Alaska, our current President and Secretary seem to see us as ‘Alaska, the National Park and Wildlife Refuge’ — a broad expanse of wilderness, with little else of interest or value.’” It is a sentiment that was echoed by other senators from mostly red states throughout the hearing.

Zinke attempted to appease concerns about his ability to work with both sides of the aisle. “Even in this body, we are all different, but we all share a common purpose: to make our country great again. As secretary of the interior, I will have inherited 70,000 hard charging, dedicated professionals that want to do the same thing,” he said. “My task is to organize for a better future for interior and our country. I will work with anybody, as the list would indicate. I’ve never been red or blue. To me it has always been red, white and blue.”

Environmentalists, opposed to Zinke, must now hope awareness of the disappearance of our white glaciers might promote coordinated action between red and blue leadership under the new secretary, before it is too late.

 

 

Research Shows How Climate Change Drives Glacier Retreat

Shrinking glaciers are oft-cited examples of the effects of anthropogenic climate change, providing dramatic imagery in different parts of the world. However, this has mostly been based on global aggregates of glacier extent. Differing opinions also exist about the best way to measure glacial change all over the world.  A recent study by Roe et al., published in Nature Geoscience, confirms that climate change has contributed to the shortening of numerous glaciers around the world, but the study is not immune to controversy surroundings the methods used.

Retreating glaciers, such as these in the Himalayas, are a popular symbol of climate change (Source: NASA/Creative Commons).
Retreating glaciers, such as these in the Himalayas, are a popular symbol of climate change (Source: NASA/Creative Commons).

Using a combination of meteorological data and observations of glacier length, Roe et al. studied the influence of climate on 37 glaciers between 1880 and 2010. The glaciers were selected based on the continuity of length observations and the need for a wide geographical distribution.

Glacier mass-balance records are a more direct measure of the effect of climate than glacier length as they measure the difference between the accumulation and ablation (sublimation or melting) of glacier ice. However, most mass-balance records do not extend for more than two decades, contributing to the previous lack of confirmation of the effect of climate change on individual glaciers around the world.

The use of observations of glacier length helped to overcome this obstacle, but challenges were still encountered in obtaining long, continuous data sets, particularly for regions such as Asia and South America. In conversation with GlacierHub, Roe shared that many factors can affect the availability of continuous data sets. “For example, the collapse of the Soviet Union led to many glacier observation programs being abandoned,” he stated.

The researchers tracked changes in the length of 37 glaciers, including those highlighted here (Source: Roe et al./Nature Geoscience).
The researchers tracked changes in the length of 37 glaciers, including those highlighted here (Source: Roe et al./Nature Geoscience).

An additional challenge arose from the variation in conditions experienced by each glacier. “Every glacier is a unique product of its local climate and landscape,” Roe shared, citing the example of maritime glaciers, which typically experience a large degree of wintertime accumulation variability. “This can mask the signal of a warming that, so far, has mainly impacted the summertime mass balance,” he added.

Nevertheless, Roe et al. found that there was at least a 99% chance that a change in climate was needed to account for the retreat of 21 of the glaciers studied. “Even for the least statistically significant (Rabots Glacier in Sweden), there was still an 89% chance that its retreat required a climate change,” Roe said.

As glaciers tend to have decadal responses to changes in climate, their retreat since 1880 is likely to be a result of twentieth-century temperature trends. They also act as amplifiers of local climate trends, providing strong signal-to-noise ratios that serve as strong evidence for the effects of anthropogenic climate change. For example, one of the glaciers included in the study, Hintereisferner in the Austrian Alps, retreated 2,800m since 1880, with a standard deviation (a measure of the deviation of values from the mean) of 130m. This value is small compared to the amount of retreat, providing a strong signal of change.

Hintereisferner was one of the 37 glaciers included in the study (Source: Creative Commons)
Hintereisferner was one of the 37 glaciers included in the study (Source: Woodsiailvensis/Creative Commons).

“We hope that these results will lead to a stronger scientific consensus about the cause of glacier retreat. The last round of the Intergovernmental Panel on Climate Change was quite timid, concluding only that it was ‘likely’ that a ‘substantial’ part of glacier retreat was due to human-caused climate change,” Roe added. IPCC nomenclature would make it “very likely” (≥90%) that all but one of the glaciers in this study have retreated because of climate change, allowing for stronger conclusions to be drawn.

Excitement about the results of this study was shared by Joerg Schaefer, professor at the Lamont-Doherty Earth Observatory: “Under Roe’s lead, the really smart glacier people find ways to explain this strange observation that glaciers are highly individual beasts if you look at short time scales (years and decades), but behave like a flock of well-behaved sheep when you look at longer (centennial and millennial time-scales),” Schaefer said in an interview with GlacierHub. “This will help us a lot down the road to better predict rates of glacier change for the next century.”

In contrast, Mauri Pelto, professor of environmental science at Nichols College who has been involved in the North Cascade Glacier Climate Project for 34 of years, expressed that the paper was interesting but not the first confirmation of glaciers being impacted by anthropogenic climate change. “This does not mean it is not worth writing about,” said Pelto, “but it needs to be placed in the context of the other key studies that were both earlier, and, I believe, stronger.”

For example, the authors looked at fewer glaciers than Oerlemans et al. (2005) while modelling each in more detail. Pelto notes that they also used far less data than Zemp et al. (2015) in making an even more compelling statement on the status of glaciers. Finally, the authors are not the first to conduct an attribution study: note Marzeion et al. (2014). While their statistical method is quite robust, their modelling approach that generates data does not have an impressive verification record, according to Pelto.

“Other recent studies better represent the certainty of glacier change being driven by climate,” Pelto concluded.

These opinions indicate that glacier retreat continues to attract attention and stimulate active debate, pointing to the importance of glaciers and climate change. The approach used in this study relies on glacier length, a less precise measure than mass-balance. However, its value lies in the ability to consider long meteorological and glacier length records for a number of glaciers, contributing to an important and growing body of knowledge about the effects of anthropogenic climate change on glaciers all over the world.

Ion Concentrations Are Growing in Himalayan Lakes

The Group Photo of the Whole Team Taken in Himalaya ( Source: Dr. Salerno)
A group photo of the research team taken in the Himalayas (Source: Franco Salerno).

Dr. Franco Salerno and a team of Italian researchers conducted long-term field work in the Himalayan area, discovering a dramatic increase of ionic concentrations in glacial lakes. This increase may lead to some large and irreversible environmental effects, according to Salerno et al. A report detailing their findings was published in the journal of Environmental Science & Technology in July.

Over the past two decades, Dr. Salerno and his team have observed a significant rise in ionic content in a total of 20 remote high-altitude glacial lakes located in central southern Himalaya. When asked by GlacierHub about why his team conducted their research in the Himalayan region, Dr. Salerno said, “The Italians have a long experience and passion for the high mountains. The culture and the capacity to climb is probably born around the Alps, and also drove us to study the Himalayan glaciers.”

The group had to overcome many difficulties to perform their research including low temperatures, language barriers, and even snowblindness. But thanks to help from the local people, they managed to finish their research. The scientists also received support from the Ev-K2-CNR Association and the Italian National Research Council (CNR) to conduct studies in the Hindu Kush – Karakorum – Himalaya region and the countries of Nepal, Pakistan, China (Tibetan Autonomous Region) and India.

Dr. Salerno and his team are doing field research (Source: Dr. Salerno).
Dr. Franco Salerno and his team conducting field research (Source: Franco Salerno).

Among their findings, the team detected a substantial rise of in-lake chemistry determined mainly by the sulfate concentration. LCN9, one of the 20 lakes monitored on an annual basis for the last 20 years, was found to have sulfate concentrations that increased by over 4-fold over that time period. In this region, the researchers also observed a significant relationship between the increase in the annual temperature recorded in the area and the enhanced conductivity in two glacial lakes.

After examining several factors, including temperature, precipitation, rocks and soil weathering processes, and seasonal snow cover duration, they concluded that glacier retreat likely was the main factor responsible for the observed increase of sulfate concentrations. Moreover, the weakened monsoon of the past two decades has partially contributed to the lakes’ enrichment through runoff waters that are concentrated in solutes and by lowering the water table, resulting in more rock exposed to air and enhanced mineral oxidation.

Scientists record daily data (Source: Dr. Salerno).
Scientists record daily data (Source: Franco Salerno).

The higher mineral contents have not threatened the ecosystems, but high mountain ecosystems can be especially vulnerable to climate change. The change may lead to some negative outcomes not yet foreseen. Research in other areas including the Florida Everglades, California Limekiln Creek and Vestfold Hills have shown the negative impacts of increased sulfate concentrations on lake ecosystems. By the same token, a notable increase of ionic concentrations may lead to irreversible changes to the fragile local ecosystem, biodiversity in the lakes or even human health.

As Dr. Salerno commented, “We think that the glacier masses in this region are decreasing as coupled effect of the global warming and the weakness of the monsoon. Even if these changes do not pose a direct and immediate threat to the ecosystem, they occurred in a limited time span and significantly modified the average chemical composition of lake water, which will cause some potential changes in the future.”

 

Roundup: Porcupine Glacier, Patterned Ground and Ciliates

Roundup: Glacier Calving, Ciliates and the Alps

 

A calving event in Porcupine Glacier shows rapid retreat

From the American Geophysical Union: “Porcupine Glacier is a 20 km long outlet glacier of an icefield in the Hoodoo Mountains of Northern British Columbia that terminates in an expanding proglacial lake. During 2016 the glacier had a 1.2 square kilometer iceberg break off, leading to a retreat of 1.7 km in one year. This is an unusually large iceberg to calve off in a proglacial lake, the largest ever seen in British Columbia or Alaska… The retreat of this glacier is similar to a number of other glaciers in the area: Great Glacier, Chickamin Glacier, South Sawyer Glacier and Bromley Glacier. The retreat is driven by an increase in snowline/equilibrium line elevations which in 2016 is at 1700 m, similar to that on South Sawyer Glacier in 2016.”

Learn more about the retreat of Porcupine glacier, and view satellite images here.

A glacier in Kenai National Park, where Porcupine glacier is located
A glacier in Kenai National Park, where Porcupine glacier is located (Source: Dubhe/Wikimedia Commons)

 

Patterned ground exposed by glacier retreat in the Alps

From the Biology and Fertility of Soils: “Patterned ground (PG) is one of the most evident expressions of cryogenic processes affecting periglacial soils, where macroscopic, repeated variations in soil morphology seem to be associated with small-scale edaphic [impacted by soil] and vegetation gradients, potentially influencing also microbial communities. While for high-latitude environments only few studies on PG microbiology are available, the alpine context, where PG features are rarer, is almost unexplored under this point of view… These first results support the hypothesis that microbial ecology in alpine, periglacial ecosystems is driven by a complex series of environmental factors, such as lithology [study of the general physical characteristics of rocks], altitude, and cryogenic activity, acting simultaneously on community shaping both in terms of diversity and abundance.”

Learn more about glacier retreat in the Italian Alps here.

Glaciers in the Italian Alps
Glaciers in the Italian Alps (Source: Glac01 /Wikimedia Commons)

 

Microorganisms found in glacial meltwater streams

From Polar Biology: “Microbial communities living in microbial mats are known to constitute early indicators of ecosystem disturbance, but little is known about their response to environmental factors in the Antarctic. This paper presents the first major study on ciliates [single-celled animals bearing cilia] from microbial mats in streams on King George Island (Antarctica)… Samples of microbial mats for ciliate analysis were collected from three streams fed by Ecology Glacier. The species richness, abundance, and biomass of ciliates differed significantly between the stations studied, with the lowest numbers in the middle course of the stream and the highest numbers in the microhabitats closest to the glacier and at the site where the stream empties into the pond. Variables that significantly explained the variance in ciliate communities in the transects investigated were total organic carbon, total nitrogen, temperature, dissolved oxygen, and conductivity.”

Learn more about the ciliates here.

One of the glaciers on King George Island
One of the glaciers on King George Island (Source: Acaro/Wikimedia Commons).

Roundup: River Outlets, Plant Habitats, and Village Partners

Roundup: Canadian River Vanishes, Plants in the Himalayas and Pakistan’s Villages

Glacier retreat in Canada causes Yukon river to vanish.

From CBCNews: “It’s been the main source of water into Yukon’s Kluane Lake for centuries, but now the Slims River has suddenly slimmed down — to nothing. ‘What folks have noticed this spring is that it’s essentially dried up,” said Jeff Bond of the Yukon Geological Survey. ‘That’s the first time that’s happened, as far as we know, in the last 350 years.’ What’s happened is some basic glacier hydrology, Bond says — essentially, the Kaskawulsh Glacier has retreated to the point where its melt water is now going in a completely different direction, away from the Slims Valley. Instead of flowing north 19 kilometres from the glacier’s toe into Kluane Lake (and ultimately, the Bering Sea), that melt water is now draining eastward via the Kaskawulsh River towards the Pacific Ocean off the Alaska panhandle. It’s a reminder that glacier-caused change is not always glacial-paced.”

Read more about the effects of glacier retreat on the Slims River here:

slims-river-valley
The Slims River Valley in Canada following glacier retreat (source: Sue Thomas/CBCNews).

 

The world’s highest vascular plants found in Indian Himalayas.

From Microbial Ecology: “Upward migration of plants to barren [just below the snowl areas is occurring worldwide due to raising ambient temperatures and glacial recession. In summer 2012, the presence of six vascular plants, growing in a single patch, was recorded at an unprecedented elevation of 6150 m.a.s.l. close to the summit of Mount Shukule II in the Western Himalayas (Ladakh, India). Whilst showing multiple signs of stress, all plants have managed to establish stable growth and persist for several years.”

Learn more about the role of microbes in the process of plant upward migration here.

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Six plant species found over 6000 meters in the Indian Himalayas (source: Microbial Ecology).

 

Local struggles in Pakistan show adaptations to glacier thinning.

From Erdkunde: “Framing adaptation as a process of assemblage-building of heterogeneous human and non-human [actors], two village case studies are investigated where glacier thinning has dried up a source of irrigation water, turning cropland into desert. While in the first case case, villagers were able to construct a new and extraordinary water supply scheme with the help of external development agencies, in the second case, several approaches to utilize alternative water sources over three decades were unsuccessful. An account of the adaptation assemblages shows how a diversity of actants such as individual leaders, community, external agencies, construction materials, landslides and geomorphological features play variable and contingent roles in the success or failure of adaptation efforts, thus co-defining their outcome in complex ways.”

Learn more about the adaption efforts to glacier thinning in northern Pakistan here.

View of the Barpu Glacier (source: Michael Spies/Erdkunde)
View of the Barpu Glacier’s former meltwater stream (source: Michael Spies/Erdkunde).

Could Glacier Retreat Cause Seals to Wander?

Though populations of harbor seals – the captivating species seen in almost every zoo – are stable in other areas of the world, they are seeing declines in southeastern Alaska. These particular seals use icebergs calved from nearby glaciers as a place to rest and breed, but changes in ice availability are affecting these behaviors, crucial to their survival and reproduction.

Two separate studies, one by the National Park Service (NPS) and one by the Alaska Department of Fish and Game (ADFG), have independently found that seals may be changing their distribution and behavior to match the shifting locations of ice, as glaciers retreat.

Seals taking a break on top of a flat ice berg. (Courtesy of : Jamie Womble/National Park Service))
Seals taking a break on top of a flat iceberg. (Courtesy of: Jamie Womble/National Park Service)

Jamie Womble, leading the NPS research in Glacier Bay, is providing a new way of relating glacier ice extent and harbor seal territory, both in location and seasonality. Womble and her team aim to find the exact distribution and movements of these Alaskan harbor seals. Aerial tracking– flying above the ice and counting the seals–is a method that works effectively in the region. They also glue GPS transmitters to the seals, and track their movements on land-based monitors. These transmitters come off safely during the next summer’s molt, so they present only minimal risk to the animals.

Womble and her team found that “[d]espite extensive migration and movements of seals away from Glacier Bay during the post-breeding season, there was a high degree of inter-annual site fidelity (return rate) of seals to Glacier Bay the following pupping/breeding season.”

Harbor seal wearing GPS tracking device used in NPS research. (Courtesy of :National Park Service))
Harbor seal wearing GPS tracking device used in NPS research. (Courtesy of: National Park Service)

In addition to studying the distances which the seals traveled, Womble and her group also examined the patterns of seal movement in relation to the glacial ice. The team studied the ice distribution within John Hopkins Inlet, which they coordinated with aerial tracking data to examine the relationship between the ice extent and the harbor seals.

John Hopkins Inlet, the main area of research for Womble, is home to Johns Hopkins Glacier and Gilman Glacier which are among the few advancing glaciers in this region. Seals were found to congregate in areas with the highest percentage of ice.

Aerial image of harbor seals. (Courtesy of :National Park Service))
Aerial image of harbor seals. (Courtesy of: National Park Service)

“Tidewater glacier fjords in Alaska host some of the largest seasonal aggregations of harbor seals in Alaska,” Womble told GlacierHub in an interview. Many of these tidewater glaciers – glaciers that run into the sea and calve frequent icebergs – are thinning, and a few have begun retreating.

In particular, rapid retreat on the east side of Glacier Bay is leading to decreased seal pupping. During this critical season when the pups are newborn, mother seals and the weaning baby seals use flat icebergs to rest. “By 2008, no seals were pupping in Muir Inlet, and fewer than 200 seals were counted in McBride Inlet near the terminus of the McBride Glacier, the only remaining tidewater glacier in the East Arm of Glacier Bay,“ the NPS team stated in a recent report.

John Hopkins glacier, one of the few advancing glaciers in southeastern Alaska. (Courtesy of :Peter Makeyev/Flikr)
John Hopkins glacier, one of the few advancing glaciers in southeastern Alaska. (Courtesy of: Peter Makeyev/Flikr)

In a report, ADFG  emphasizes the importance of  studying  “…why, how, and when harbor seals use glacial habitat, and whether the rapid thinning and retreat of Alaskan glaciers associated with climate change could negatively affect harbor seals…” Their research documented similar instances of glacier thinning and retreat and they are also monitoring seal movement, as well as other topics, including seal diet, seal weight and bodily composition and disturbances by tour vessels. Though ADFG began their work in Glacier Bay, the same site as the other team, they moved their research to Tracy Arm Ford’s Terror Wilderness Area – more than 200 miles to the southeast.

The ADFG team has attached transmitters such as SPOT  to track the seals. These beam data on location, heart rate and other biological indicators up to satellites. To gather data, the researchers depend on the seals surfacing to breathe or rest, since the satellites cannot receive signals that are released underwater. The tracking for both research projects was most important during winter months, since researchers were interested in monitoring movement and feeding after the summer breeding season. (More tracking information, here)

Harbor seals, said to be awkward on land, use icebergs as a place of safety from predators. (Courtesy of :Jamie Womble/National Park Service))
Harbor seals, said to be awkward on land, use icebergs as a place of safety from predators. (Courtesy of: Jamie Womble/National Park Service)

ADFG also saw regular return rates for the sea populations which they studied. They hypothesized that they may travel to find food in the winter, but still return to Glacier Bay in the summer for the safety that icebergs provide from land-based predators. Icebergs are also important sites for the animals to haul out, since many beaches are entirely covered during high tides.

The ongoing research conducted both by Womble’s group and by the Alaska Department of Fish and Game show how recent changes in glaciers have already had large effects on the seal life cycle, specifically pupping. Continued monitoring of seal reproduction and movement in the context of glacier retreat will allow for predictions of the future of this important species in a critical section of its range.

If You Can’t Handle the Heat – Retreat

Zachariæ Isstrøm, a large glacier in the northeast coast of Greenland, is in a state of accelerated retreat after it detached from an important sill. This shift has caused great instability for the glacier, according to a new study from Science Magazine.

Recognizing 0.5 meters of possible sea level rise held within Zachariæ, and its acceleration expected to continue, the authors point to an increased likelihood of sea level rise coming from this area in the next 20 or 30 years. This study is noteworthy since Zachariæ is found far north, close to 79 degrees N. The Greenland glaciers which have been highlighted for their fast retreats to date are found further south. 

Zachariæ Isstrøm retreat (2003-15) captured by NASA/USGS Landsat satellite (Courtesy of :NASA/USGS)
Zachariæ Isstrøm retreat (2003-15) captured by NASA/USGS Landsat satellite (Courtesy of :NASA/USGS)

Jeremie Mouginot from the University of California, Irvine and his coauthors looked specifically at the effects of warming ocean and air temperatures on the melting and discharge dynamics of the glacier. (More Greenland work from the UCI team can be found here.)

The precise measurements of the ice discharge data were made possible by NASA, who provided funds and much of the data and equipment. 

Zachariae Isstrom and Nioghalvfjerdsfjorden - a similar glacier currently seeing less drastic changes (Courtesy of :NASA/USGS)
Zachariae Isstrom and Nioghalvfjerdsfjorden – a similar glacier currently seeing less drastic changes (Courtesy of :NASA/USGS)

The researchers observed a 50% increase in the retreating speed since 2000. There was also a doubling of ice thinning. On the ice shelf, this process was extensive enough to be measured by satellites. Data showed Zachariæ in a stable state up until 2003 when a large piece broke off. Since that breaking point Zachariæ retreated at a steady state until 2013-14 when the retreat accelerated. It is now retreating at a rate of 125 meters per year and losing 5 gigatons of mass yearly.

The increased mass loss is attributed by the authors to a combination of warming air and ocean temperatures. These changes lead to increased ice loss by way of calving, as opposed to changes in the accumulation of mass through precipitation. 

Ocean temperatures play an important role in glacier retreat; the authors argue that the nearly 1 degree C increase in ocean temperatures near the glacier is largely responsible for triggering the enhanced retreat.

Warming air temperatures lead to an increase in ice thinning which affects the placement of the grounding line below the surface – an important transition area where the glacier begins floating.  As the grounding line retreats there is increased surface area of the glacier exposed to the melting from below. Zachariæ began to calve so rapidly at the grounding line in 2014 that the remaining ice shelf was “95% smaller than in 2002” according to the researcher’s Landsat optical imagery data.

The authors did speak of another glacier in the Northeast of Greenland that is also experiencing accelerations-Nioghalvfjerdsfjorden Glacier (NG). Though the overall changes on NG were not as rapid as Zachariæ, the authors suggest that NG will become more vulnerable in the future.

A tidewater glacier, Margerie Glacier, in Glacier Bay Alaska.(Courtesy of :LH Wong/Flikr)
A tidewater glacier, Margerie Glacier, in Glacier Bay Alaska.(Courtesy of :LH Wong/Flikr)

“Not long ago, we wondered about the effect on sea levels if Earth’s major glaciers were to start retreating,” said one of the authors, Eric Rignot. “We no longer need to wonder; for a couple of decades now, we’ve been able to directly observe the results of climate warming on polar glaciers. The changes are staggering and are now affecting the four corners of Greenland.”

Isstrøm, a Danish phrase that translates as ice stream, seems to take on a poetic meaning when one thinks of the drastic amount of ice now “streaming” from the glacier.

As Zachariæ transitions into a tidewater glacier, it can be expected to calve more icebergs and become more vulnerable to increases in ocean temperatures. With other glaciers in this area retreating quickly Greenland will be an important region to watch in the coming decades, the authors concluded.

Here is a quick video illustrating how the position of the grounding line can accelerate retreat of a glacier by increasing the area exposed to currents.