Photo Friday: These Glacier-Covered Volcanoes in Chile Could Soon Erupt

Stretching over 7,000 kilometers across seven countries, the Andes are the world’s longest mountain range. They make up the southeastern portion of the Ring of Fire and are well-known for their abundant volcanoes.

The Chilean Andes are home to 90 active volcanoes, all monitored by the Chilean National Geology and Mining Service (Sernageomin). The agency categorizes volcanic activity using four distinct alert levels: green (normal level of activity), yellow (increased level of activity), orange (probable development of an eruption in the short-term), and red (eruption is ongoing or imminent). Increased volcanic activity is associated with frequent earthquakes; plumes of gas, rocks, or ash; and lava flows.

Two areas monitored by Sernageomin are currently showing signs of increased activity: the Nevados de Chillán and Planchón-Peteroa volcanic complexes. The agency issued orange and yellow alert levels for them, respectively.

A satellite image of the Nevados de Chillán volcano complex, showing the glacier-covered volcano peaks (Source: Sernageomin).

Nevados de Chillán Volcanoes: Orange Alert

The Nevados de Chillán volcano complex is comprised of several glacier-covered volcanic peaks. When these volcanoes erupt, the glacial ice sitting atop them melts and mixes with lava, which can result in dangerous lahars, or mudflows. Several small earthquakes and the formation of new gas vents led Sernageomin to issue a yellow alert on December 31, 2015. (To view a detailed map of the Nevados de Chillán complex, click here.)

On April 5, 2018, Sernageomin upgraded the Nevados de Chillán’s yellow alert to an orange alert, following thousands of tremors and a thick, white column of smoke rising from the area. This signaled the likelihood of an eruption in the near future.

Sernageomin’s most recent volcanic activity report for Nevados de Chillán, issued on February 11, 2019, cited persistent seismic activity, which is directly related to increased frequency of explosions, along with the growth and/or destruction of the lava dome that lies in the crater. The expected eruption is most likely to have moderate to low explosive power, but sporadic observations over the last year have shown higher than average energy levels.

On February 15, 2019, the Volcanic Ash Advisory Center in Buenos Aires documented a volcanic-ash plume reaching 3,700 meters high at Nevados de Chillán, an example of the above mentioned “higher than average energy levels.”

Read more on GlacierHub:

Eruption in Glacier-covered Volcano in Chile

A Glacier-covered Volcano in Chile: Will It Erupt Soon?

Photo Friday: Code Yellow at Mount Veniaminof

Images Show Active, Glacier-Covered Volcanoes in the Russian Far East 

Drones in the Service of Sustainability: Tracking Soil Moisture in the Peruvian Andes

Amid the tropical Andes of Peru lies the Cordillera Blanca mountains, home to more tropical glaciers than anywhere else on Earth. This range provides water to some 95 million people. Rising temperatures over the last several decades, however, mean its once abundant glaciers are vanishing rapidly. That’s impacting the water supply of downstream communities, which are becoming increasingly dependent on soil moisture.

In an innovative study published in the journal Remote Sensing of Environment, researchers used drones to obtain high-resolution images of the valleys left behind as Cordillera Blanca’s glaciers recede. As the drones pass over these “proglacial valleys,” they can produce highly accurate maps of the soil moisture within the fields, rivers, wetlands, and meadows below.

Historically there has been “very little understanding” of how water circulates in areas like proglacial valleys, Jorge Recharte, director of the Andes program at the Mountain Institute, told GlacierHub.

The study’s lead author, Oliver Wigmore of the University of Colorado, Boulder, said his team’s findings help to improve understanding of proglacial hydrology. “This data … is providing unique insights into the patterns and processes that move and store water within these dynamic proglacial environments,” he said.

A view of Huandoy, the second-tallest peak in the Cordillera Blanca, at sunrise. Just beneath it is the Llanganuco Valley, which was surveyed in the study. (Source: cookierace/Flickr)

This study is the first to apply drone images to the temperature vegetation dryness index (TVDI) method. TVDI demonstrates the relationship between land surface temperature and normalized difference vegetation index (NDVI), which measures an area’s greenness, or density of vegetation, which can then be used to determine soil moisture.

Anais Zimmer, a Ph.D candidate in the department of geography and the environment at the University of Texas, Austin, said the study offered “excellent outcomes on surface and subsurface hydrological processes that could be used at a broader scale and applied to many other sub-disciplines to understand the functioning and the future of alpine ecosystem services.”

The researchers found that soil moisture varied drastically over very short distances. “The unique, high-resolution multispectral drone imagery that we collected has provided an unprecedented snapshot of the spatial variability of surface soil moisture within these systems,” said Wigmore.

high elevation drone on GlacierHub
A photo of one of the drones used to conduct this study. (Source: Wigmore, et al.)

Drones are essentially the third generation of technology to be used in scientific research. First were direct measurements, which cannot be accurately generalized over such a variable area. Then came remote sensing using satellites, which provides averaged data over larger areas, but would likely miss any important variability happening on a smaller scale. For this study, researchers used two types of drone-mounted cameras: one to measure greenness, an indicator of plant health, and a second to record temperature.

“[The images] provide excellent tools to establish comparisons between valleys, depending on land use changes and climatic factors,” Zimmer said. 

Wigmore and his team conducted their survey in two proglacial valleys in the Cordillera Blanca that were markedly different from each other in terms of precipitation level, glacier extent, land cover, and land use. The researchers found that soil moisture variability across the Cordillera Blanca’s proglacial valleys can be attributed to three criteria: distance from local water supplies; the type and abundance of vegetation; and soil disturbance such as animal grazing.

“We have found that the proglacial valleys in Cordillera Blanca often have substantial groundwater reservoirs that regulate dry season stream flow by storing and gradually releasing wet season precipitation and glacial meltwater,” said Wigmore. He added that knowing the groundwater storage capacity of these valleys could help minimize negative impacts of meltwater decline on downstream communities.

Cordillera Blanca Laguna 69 on GlacierHub
A view of a glacier in the Cordillera Blanca from the Laguna 69, one one of the most famous hikes in Peru. (Source: Esmée Winnubst)/Flickr)

“Research in these high landscapes is key to planning for both local impacts in the short term and whole-watershed impacts in the long term,” Recharte said.

Zimmer emphasized the need for enhanced monitoring, modeling, and case studies that might help to better predict the impact of climate change in mountain communities.

Around the world, many glaciers have already reached peak discharge, which threatens the freshwater supplies of downstream communities. The study by Wigmore and his team not only provides an unprecedented look into the hydrology of proglacial valleys, it also provides a glimmer of hope that not all is lost, at least for now. Their results document the enormous water-storage potential that lies beneath the surface of proglacial valleys, but also highlights the extreme vulnerability of these ecosystems.

Read more on GlacierHub:

Hindu Kush Himalaya Assessment Outlines Potentially Dire Impacts of Climate Change

COP24 President Highlights Risk of Political Instability During NYC Visit

A Survey of the UNESCO Andean Glacier Water Atlas

Roundup: Lichen Colonization, Mercury Contamination, and Double Exposure

In this week’s Roundup, read about lichen colonization on Svalbard’s glaciers, mercury inputs from glacial rivers in High Arctic Canada, and the impact of both climate change and globalization on a small village in the Indian Himalayas.

Lichen Colonization on Svalbard’s Glaciers

From Acta Societatis Botanicorum Poloniae: “The high number of lichen species that were new to Svalbard indicates the need for further research on the biodiversity of lichens in the Arctic. In particular, the glacier forelands deserve attention if further warming of the climate continues, as species sensitive to competition from vascular plants will move into habitats in the vicinity of glaciers.”

Read more here.

Lichen in Svalbard on GlacierHub
A colony of Lichen in Svalbard (Source: lnk75/Flickr).

Mercury Contamination in High Arctic Canada

From Environmental Science & Technology: “Glacial rivers were the most important source of MeHg and THg to Lake Hazen, accounting for up to 53% and 94% of the inputs, respectively. However, due to the MeHg and THg being primarily particle-bound, Lake Hazen was an annual MeHg and THg sink…This study highlights the potential for increases in mercury inputs to arctic ecosystems downstream of glaciers despite recent reductions in global mercury emissions.”

For more detail, click here to read GlacierHub’s recent post regarding this study.

Henrietta Nesmith glacier Lake Hazen on GlacierHub
A glacial river from the Henrietta Nesmith glacier, which flows into Lake Hazen (Source: Judith Slein/Flickr).

“Double Exposure” in Indian Himalayan Communities

From Environmental Science & Policy: “This study uses a living with approach to explore how change and development was experienced by a small agricultural community in the Indian Himalayas. The findings reveal ‘double exposure’ to an increasingly deficient water supply, and aspects of globalisation.”

Read more here.

village in Indian Himalayas on GlacierHub
A small village, nestled within the Indian Himalayas (Source: K/Flickr).

 

GLOF Risk Perception in Nepal Himalaya

Khumbu valley Mt. Everest region Nepal on GlacierHub
Overlooking a village and glacial river in the Khumbu valley, Mt. Everest region of Nepal (Source: Matt W/Flickr).

Glacial lake outburst floods (GLOFs) pose a significant, climate change-related risk to the Mt. Everest region of Nepal. Given the existence of this imminent threat to mountain communities, understanding how people perceive the risk of GLOFs, as well as what factors influence this perception, is crucial for development of local climate change adaptation policies. A recent study, published in Natural Hazards, finds that GLOF risk perception in Nepal is linked to a variety of socioeconomic and cultural factors.

Sonam Sherpa, lead author of the study and PhD candidate at Arizona State University, spoke to GlacierHub about the study’s primary objectives. She and the other researchers aimed to “capture the complex natural-social system interactions of cryospheric hazards in the Nepal Himalaya.” She further emphasized the importance of understanding how communities, “perceive the risk coming from glacial lake outburst flood, as perceptions can influence their actions, beliefs, and responses to natural hazards and associated risks.”

GLOFs occur when a lake’s natural barrier, usually a moraine, suddenly fails. The trigger can be a natural disruption, like a landslide, earthquake, or avalanche, or simply the buildup of excess water pressure from increased melt. GLOFs result in a rapid discharge of a lake’s water, inundating the downstream ecosystem with little to no warning. These events are destructive and endanger the lives and livelihoods of communities downstream.

Himalaya Nepal on GlacierHub
The Himalaya in Nepal (Source: cb@utblog/Flickr).

While scientists are clear about the threats posed by GLOFs, downstream communities often ignore or underestimate the potential impact floods could cause to life and livelihoods. So what are the factors contributing to how communities perceive this risk, and what factors influence their opinions?

The researchers conducted a survey of 138 households across nine villages within the Mt. Everest region. The survey elicited self-reported demographic information, such as age, gender, and sources of income. It also assessed risk perception regarding climate change, natural hazards, and hazards specific to regions with glaciers.

One survey question asked locals to rank various hazards “based on their likelihood and potential to damage.” Twenty seven percent of people ranked earthquakes first, while 23 percent put glacial floods first.

The researchers noted the 7.4 magnitude Gorkha earthquake in Nepal one year before, and attributed this result to cognitive availability, whereby recent or common events are more readily recalled than rare events. Sherpa, who is from the Khumbu area within the Mt. Everest region, even recalled her own fear that a glacial lake outburst flood would occur following the Gorkha earthquake.

In addition, the researchers found that rapid-onset events, namely earthquakes and GLOFs, were consistently ranked much higher than slow-onset impacts of climate change, such as changing weather patterns and water availability. GLOFs and earthquakes, though infrequent, occur rapidly and have catastrophic impacts, so people fear these events more.

Experience was a huge influence on risk perception. Both among individuals and communities that had previously experienced a GLOF event, the researchers observed a direct correlation between their experience and their perception of GLOFs as a critical threat.

When responses were analyzed by demographic, however, there was increased variation in the results. For example, young people perceived GLOFs as a greater risk than older people. The researchers surmised that media exposure coupled with more sources of information on climate change among the younger generation could explain this result.

Dingboche village in Nepal on GlacierHub
A view of the Dingboche village in Nepal (Source: smallufo/Flickr).

In search of more factors influencing risk perception, the researchers chose two of the nine villages to compare—Dingboche and Monjo. The two villages are located in different altitudinal zones, Monjo at 2,835 meters and Dingboche at 4,350 m, are considered high-risk areas for GLOFs. Residents of Monjo perceived the most risk from earthquake, then unseasonal rainfall, and finally  drought, while residents of Dingboche ranked earthquake, GLOF, then wind in order of risk.

“As a local Sherpa from Khumbu (the Mt. Everest region) myself, I had a little hint with regard to how one would perceive risk from glacial hazard based on spatial proximity,” said Sherpa. “It was surprising to see that in the data showed a similar result as well.”

The study identifies several reasons for the two villages’ variety in rankings. First is their geographical location. At its higher altitude, Dingboche is in closer proximity than Monjo to glacial lakes. The Dingboche village sits directly below Imja Lake, a heavily studied glacial lake which scientists categorize as a moderate to critical GLOF risk.  

Geographical location further influences the primary source of livelihoods. Villages dependent on tourism are more likely to have access to have information about GLOF risks. Dingboche is heavily dependent on tourism because its altitude is too high to support much agriculture. In contrast, Monjo relies equally on the tourism and agriculture industries.

Imja Tsho on GlacierHub
A shot of Imja Tsho, the lake which stretches across the middle of the photograph. Taken in 2012, four years before the remediation project took place (Source: Kiril Rusev/Flickr).

In 2016, Imja Lake underwent emergency remediation work to lower its water levels by 3.5 m. Following the project’s completion, perceived risk of GLOFs decreased in Monjo, but not in Dingboche. For Monjo, the remediation was a cognitive fix, but not for Dingboche. The project lowered the probability of a GLOF occurring, but as the closest village to Imja Lake, residents of Dingboche continued to perceive it as a critical threat to their community. Sherpa noted the remediation’s function as a cognitive fix as one of the study’s most interesting results, following the finding that proximity was a huge influencing factor on risk perception.

“I went through an emotional roller coaster thinking how rapid the changes are, in the glacial system and how it could impact my community, but at the same time how, very little is understood with regard to what’s happening in this biophysical system,” said Sherpa. Through this risk perception analysis, the researchers aimed to emphasize the necessity of including locals in the development of climate change adaptation policies.

Accurate scientific information is critical, but it is equally as important to communicate potential hazards properly so communities truly understand the risks they face. Only then will scientists, government, and local communities truly be able to work together to create a comprehensive plan to mitigate and adapt to the risks they face.

Roundup: Tibet’s Cryosphere, Methane Release, and Rockfall-induced GLOFs

The Tibetan Plateau’s Changing Cryosphere

From Earth-Science Reviews: “This paper comprehensively reviews the current status and recent changes of the cryosphere (e.g., glacier, snow cover, and frozen ground) in the TP from the perspectives of observations and simulations. Because of enhanced climate warming in the TP, a large portion of glaciers have experienced significant retreat since the 1960s, with obvious regional differences. The retreat is the smallest in the TP interior, and gradually increases towards the edges.”

Check out the full study here.

Tibetan Plateau mountains on GlacierHub
A view of the mountains from a green valley in the Tibetan Plateau (Source: Hans Johnson/Flickr).

 

Methane Release Under Greenland’s Ice Sheet

From Nature: “Here we find that subglacially produced methane is rapidly driven to the ice margin by the efficient drainage system of a subglacial catchment of the Greenland ice sheet…We show that subglacial hydrology is crucial for controlling methane fluxes from the ice sheet…Overall, our results indicate that ice sheets overlie extensive, biologically active methanogenic wetlands and that high rates of methane export to the atmosphere can occur via efficient subglacial drainage pathways. Our findings suggest that such environments have been previously underappreciated and should be considered in Earth’s methane budget.”

Check out the full study here.

Helheim Kangerdlugssuaq Greenland ice sheet on GlacierHub
NASA’s IceBridge flying over the Helheim/Kangerdlugssuaq region of Greenland’s ice sheet, documenting summertime melt (Source: NASA Goddard/Flickr).

 

Rockfall-induced GLOFs in Nepal

From Landslides: “On April 20, 2017, a flood from the Barun River, Makalu-Barun National Park, eastern Nepal formed a 2–3-km-long lake at its confluence with the Arun River as a result of blockage by debris. Although the lake drained spontaneously the next day, it caused nationwide concern and triggered emergency responses…This study highlights the importance of conducting integrated field studies of recent catastrophic events as soon as possible after they occur, in order to best understand the complexity of their triggering mechanisms, resultant impacts, and risk reduction management options.”

Check out the full study here.

Upper Barun Valley on GlacierHub
Upper Barun Valley, Nepal. The aftermath of the Langmale GLOF are shown on the lower left portion of the image (Source: Roger Nix/Flickr).

Glacial Rivers Release Mercury into High Arctic Watersheds

Lake Hazen Canada on GlacierHub
On the shore of Lake Hazen, Nunavut, Canada (Source: Judith Slein/Flickr).

Mercury is a contaminant which poses environmental health risks to terrestrial and aquatic ecosystems around the world, especially in the Arctic. A recent study in Environmental Science & Technology traces the source of mercury concentrations in Lake Hazen to increased flow in glacial rivers. Lake Hazen, located in Nunavut, Canada, is the High Arctic’s largest lake by volume, and reaches depths up to 267m.

There are both natural and anthropogenic sources of mercury. Global mercury emissions have been declining, specifically after ratification of the Minamata Convention. However, as anthropogenic sources decrease, climate change could be increasing natural sources of mercury—if in a less direct fashion than emissions.

Mercury is stored in permafrost and glacial ice, so as permafrost thaws and ice melts, downstream ecosystems could be impacted. Microbes can also transform mercury into a poisonous neurotoxin called methylmercury, which impacts the nervous system. Both can bioaccumulate in organisms, especially at higher levels of the food chain.

“The primary focus of the research program at Lake Hazen is on understanding the biogeochemistry of freshwater ecosystems downstream of the glaciers of the Northern Ellesmere Icefield,” said Kyra St. Pierre, the study’s lead author, in an interview with GlacierHub. St. Pierre, who conducted this research as a part of the Department of Biological Sciences at the University of Alberta, Canada, went on to say that the study aimed to explain how recent warming patterns might impact biogeochemical cycles in the future.

Henrietta Nesmith glacier river on GlacierHub
One of the glacial rivers that feeds into Lake Hazen, flowing from the Henrietta Nesmith glacier (Source: Judith Slein/Flickr).

Lake Hazen receives meltwater—and up to 94 percent of total mercury inputs—primarily from three glacial rivers. The study showed that most mercury from these rivers flowed into the lake in particulate form. This means that the particles carrying mercury are not dissolved, making the water flowing into Lake Hazen more turbid, or cloudy, than the lake’s existing water. Due to the weight of the particles it carries, turbid water is also very dense. The increased weight creates what is called a turbidity current, which efficiently deposits most of the mercury particles in the bottom of the lake.

St. Pierre named these turbidity currents the study’s most surprising result, because it revealed important aspects of how Lake Hazen’s watershed functions. “Not only do [turbidity currents] transport mercury from the surface but also oxygen and other nutrients directly to the depths of the lake,” she said.

This study is distinctive in that it approached mercury cycling at a watershed-scale instead of looking at individual system components. St. Pierre called this one of the study’s most important attributes, explaining that if, for example, they had decided to focus simply on Lake Hazen’s outflows, they would have concluded that mercury concentrations were extremely low.

western part of Lake Hazen on GlacierHub
The western part of Lake Hazen in the summer of 1997 (Source: Ansgar Walk/Wikimedia Commons_).

Lake Hazen’s turbidity currents make it a huge mercury sink. Despite huge mercury inputs from glacial rivers, the lake’s main outflow, the Ruggles River, discharges relatively small amounts of mercury and methylmercury. The researchers found that the lake sequestered over 95 percent of total mercury inputs to the system annually. Downstream in the Ruggles River, mercury concentrations rose exponentially, a result of erosion and thawing permafrost.

The High Arctic is extremely sensitive to increasing temperatures and precipitation in the context of anthropogenic climate change. Craig Emmerton and Jennifer Graydon, researchers at the University of Alberta, spoke to GlacierHub about some of the larger implications of this study. “The High Arctic is among the most rapidly changing regions on Earth and its climate is expected to become warmer and wetter,” they said, pointing out the potential role of glaciers and permafrost as developing sources of mercury with the power to contaminate freshwater and marine ecosystems.

“I think we can safely infer that as warming continues in High Arctic latitudes, we can expect a greater delivery of mercury from the cryosphere to downstream ecosystems,” said St. Pierre. Though Lake Hazen retains most mercury inputs from glacial rivers, the researchers found a 3.4-times greater water volume and 2-times higher delivery of total mercury in the notably warm summer of 2015, than in the much cooler summer of 2016. So, as glaciers continue to melt, more mercury will inevitably make its way downstream.

Henrietta Nesmith River delta on GlacierHub
The Henrietta Nesmith River delta on the northwest coast of Lake Hazen (Source: Ansgar Walk/Wikimedia Commons).

Lake Hazen’s depth and size draw close similarities to High Arctic fjord systems. The researchers showed that these turbidity currents also occur in fjords indirectly fed by land-terminating glaciers. Almost 70 percent of arctic glaciers are land-terminating glaciers, and so could be important sources of mercury for marine ecosystems. More, fjords fed by marine-terminating glaciers can flow directly into high productivity zones, increasing potential for bioaccumulation in organisms and into coastal food webs.

Ultimately, this study highlights an important discovery—even with reduction of direct anthropogenic sources of mercury, there is a lingering, growing anthropogenic driver—climate change.

Video of the Week: Massive Calving Event at Helheim Glacier

In this week’s Video of the Week, watch a massive glacier calving event that occurred at Helheim Glacier in Greenland. The video was captured on 22 June 2018 by Denise Holland of New York University.

The calving event took place over a 30-minute time period, and was sped up into a time-lapse of about 90 seconds. During this time span, over four miles of the glacier’s edge broke off, flowing into one of the fjords that connects Helheim Glacier to the ocean. To put this in perspective, a calving event of this size would measure roughly the size of lower Manhattan, all the way to Midtown in New York City. In a warming world, glacier calving is a large force contributing to global sea-level rise.

Discover more news on GlacierHub:

Glaciers and Reefs with Diane Burko

Ice Loss, Gravity, and Asian Glacier Slowdown

Historical Data on Black Carbon and Melting Glaciers in Tibet

Ice Loss, Gravity, and Asian Glacier Slowdown

A recent international study found that glaciers in high mountain Asia (HMA) are actually slowing down. Researcher Amaury Dehecq of NASA’s Jet Propulsion Laboratory and his co-authors analyzed 17 years of data from 2000 to 2017, attributing their results to widespread glacial thinning. They found that 94 percent of variability in glacial flow rates could be explained by ice thickness changes.

The study asserts that glaciers are thinning worldwide and at an increasing rate from the start of the 21st century. However, according to Dehecq, exactly how glaciers respond to mass loss on a regional scale was previously not well understood. This uncertainty highlighted the necessity of understanding the consequences of glacier thinning in a warming world and catalyzed this innovative study.

Nyenchen Tanglha mountains Tibet on GlacierHub
The Nyainqêntanglha mountains of Tibet, where some of the most significant glacier slowdown is occurring as a result of ice loss (Source: randomix/Flickr).

Trending: Velocity Over Time

Dehecq and his co-researchers measured glacier surface velocity changes with 1 million satellite image pairs from Landsat-7, obtaining annual velocities by comparing images taken one year apart over the same area. This was done through feature tracking; the researchers identified specific, recognizable features (i.e. crevasses, dirt patches), then measured how far they moved from one picture to the next. They did this over and over again, millions of times, to translate the image pairs into usable velocity data.

In all, the researchers calculated velocity changes over time for 11 subregions in high mountain Asia. The most significant glacier slowdowns were seen in the Nyainqêntanglha mountains of Tibet and in the Himalayas in India (Spiti Lahaul), with 37.2 and 34.3 percent velocity decreases per decade, respectively.

Lesser but still significant slowdowns were observed for glaciers in the following regions: West Nepal, East Nepal, Bhutan, Hindu Kush, Pamir, Tien Shan, and the inner Tibetan Plateau.

velocity map for high mountain asia glaciers on GlacierHub
Velocity changes from 2000-2016 for glaciers in high mountain Asia (Source: NASA Earth Observatory).

“It is only recently that big data crunching has allowed this hypothesis to be tested on such a grand scale,” said William Colgan, a research climatologist at the Geological Survey of Denmark and Greenland, in an interview with GlacierHub.

Noel Gourmelen, a co-author of the study and professor of glaciology at the University of Edinburgh, Scotland, emphasized the importance of data availability in allowing studies like this one to be successful in the future. “This research was possible because of sustained and open Earth Observation programs,” he said, also calling for continued support, maintenance, and expansion of programs like NASA’s Landsat and ESA’s Sentinels satellite series.

On Thin Ice

Dehecq and his co-researchers matched calculated velocity trends with observations of glacier thickness from 2000 to 2017. Data on glacier thickness is obtained by using remote sensing to create a model of glacier elevation change over time. This comparison showed a strong relationship between the two; each region that observed a decreasing velocity trend also observed a corresponding trend in ice thinning over the same time period.

Colgan also spoke to GlacierHub about the trending relationships this study revealed. “This study is some of the clearest evidence to date of the link between climate forcing and ice dynamics in land-terminating glaciers,” he said. “Based on these Himalayan observations, the study is telling us to expect widespread slowdowns in ice flow in regions where glaciers are experiencing widespread thinning; that’s most regions of land-terminating glaciers.”  

Karakoram region China on GlacierHub
Muztagh Ata and Lake Karakul in the Kunlun region, one of the few places where glaciers are advancing (Source: dreamX/Flickr).

Despite the strong relationship between thinning ice and decreasing velocity, each subregion had a slightly different magnitude of change. The researchers suggested that “regional differences in climate and glacier sensitivity to temperature,” could influence small spatial variations in the overall trend.

Accordingly, this study also found that regions with advancing glaciers are speeding up. Two adjacent regions in high mountain Asia, Karakoram and West Kunlun, experienced a positive mass balance along with slight velocity increases from 2000 to 2017.

The Glacial Pace

Mountain glaciers have a simple motivation for their downhill progression—gravity. Gravity causes the surface ice on a glacier to creep, slowly deforming and thinning the glacier as it moves down the mountain.

How fast glaciers travel on this journey is controlled by two factors: gravitational driving stress and glacier thickness. Driving stress is dependent on slope. The steeper the mountain, the stronger the gravitational force. Since surface ice moves faster than the ice underneath, ice thins as a glacier travels, meaning a glacier will get progressively slower the further it goes. That is, until it reaches an elevation where the surrounding climate is warm enough to rapidly melt the ice.

Dehecq and his co-researchers concluded that these two factors alone can be used to effectively calculate glacier surface velocity. “The strength of the link between mass loss and change in flow was surprisingly strong,” said Gourmelen. “One might have expected that changes at the base of the glacier would have played a role and impacts basal sliding of the ice, but this does not appear to be the case when looking at the HMA region as a whole.”

A Warning for Warming

Mount Kailash on GlacierHub
The sacred Mt. Kailash in Tibet and surrounding mountains are home to several glaciers that feed major rivers, lakes, and communities. Read more about Mt. Kailash on GlacierHub (Source: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team).

A warming world means more glacial surface melting, and at higher elevations. However, surface melting also means ice thinning, which slows down the flow of glaciers due to gravity. So although less ice exists overall, there is also less ice reaching the elevation where it will melt.

The findings of this study improve knowledge of glacier feedbacks in the context of anthropogenic climate change regarding sea-level rise and the hydrology of certain regions. Glacial slowdown in high mountain Asia could potentially impact the availability of freshwater for communities in surrounding countries like Kazakhstan, Pakistan, India, Nepal, Bhutan, Tibet, and China.

Gourmelen gave GlacierHub an apt overview of the importance of understanding climate-glacier feedbacks:

“This is yet another sign of the impact of climate change on glaciers, the machine is slowing down. Glacier flow is a fundamental component of the glacier machine, it is the conveyor belt bringing ice from high elevation where it forms to lower elevation where it melts. This process impacts glacier met rates and glacier extent and is a key component of glacier modeling and hydrology. By providing a relationship between mass loss and flow change, parameterising model predicting future of glaciers and water availability will be made easier and more precise. It will also help interpreting some of the changes in glacier shape that we have observed in the last decades.”

Mauri Pelto, professor of environmental science at Nichols College and director of the North Cascades Glacier Climate Project, spoke to GlacierHub about the global implications of this study. “The key takeaway is the same we see for alpine glaciers around the globe, warming temperatures lead to mass balance losses, which is the key driver in glacier response,” he said. “A sustained negative mass balance leads to thinning, which leads to a glacier slow down whether the glacier is in the Himalaya, Alps, or Cascade Range.”

Pelto further explained his considerations for both the short and long-term implications of glacial slowdown in high mountain Asia. “In the short run the slow down will increase retreat rate. In the long run less dynamic mass transfer to lower elevations will lead to a reduction in glacier retreat,” he said.

In all, glacial slowdown could help preserve ice mass in the foreseeable future. However it could be at the cost of abundant freshwater for mountain communities.

Photo Friday: Norway’s Climate Quiz

This Photo Friday features pictures from an online quiz called “What Do You Really Know About The Climate?” The quiz was posted by journalists Sjur Øverås Knudsen and Gry Eirin Skjelbred of NRK, the largest media organization in Norway. Following the publication of the IPCC’s Special Report on Warming of 1.5 degrees Celsius in October 2018, these two journalists compiled a seven-question quiz so people could test their knowledge of the world’s largest emitters of CO2, factors contributing to climate change, and how food contributes to emissions. After answering each question, the quiz shows a short blurb explaining the correct answer.

Below are the photos accompanying some of the quiz questions. Click here to take the quiz (which was originally published in Norwegian), and test your climate knowledge!

 

cars driving at night on GlacierHub
Question 1 asks which listed country emits the most CO2 (Source: China Stringer Network/Reuters).

 

driver of climate change on GlacierHub
Question 4 asks what is the main driver of the climate change we see today (Source: Kai Stokkeland/NRK).

 

food on GlacierHub
Question 5 asks how food waste contributes to global greenhouse gas emissions (Source: Knut Bry/Nationen).

 

polar ice on GlacierHub
Question 6 is a True/False which asks if there is a large scientific consensus about the human contribution to climate change (Source: Harvey Goodwin/Norwegian Polar Institute).

Glaciers Feature Prominently at COP24 in Poland

From 2-14 December 2018, 197 countries gather in Katowice, Poland, for the 24th Conference of the Parties to the United Nations Framework Convention on Climate Change, or better known as COP24. During these two weeks of negotiations, countries will attempt to finish what they started in Paris three years ago. In Paris, parties set 2018 as the deadline to come up with robust plans for their Nationally Determined Contributions (NDCs), which will include significant reductions in carbon emissions as well as an increased commitment to sustainable development.

Mountain countries are taking an active role in this year’s conference, and the impact of future warming scenarios on glacier melting, sea level rise, and mountain communities has been a prominent point of discussion throughout.

16 November 2018

Postcards created by over 125,000 children from around the world are compiled into a mosaic at the base of Switzerland’s Aletsch Glacier, spelling a message across the snow. “STOP GLOBAL WARMING #1.5 DEGREES C,” it reads, serving as a gesture to countries preparing for COP24. According to Swiss glaciologists at the University of Zurich, the Aletsch glacier, though currently the largest expanse of continuous ice in Western Europe, is receding at a rate of 12 meters per year, and it could completely disappear by 2100.

The quote references the findings of the IPCC Special Report, Global Warming of 1.5ºC, published in October 2018. In order to minimize the adverse impacts of climate change, the report urged limiting global warming to 1.5 degrees Celsius instead of the 2 degrees Celsius agreed upon in Paris three years ago.

3 December 2018

“We can’t afford to fail in Katowice,” says UN Secretary-General Antonio Guterres during his opening remarks at COP24. He thinks that public will to fight climate change has faded since Paris in 2015, and now climate change is “running away from us.” Notable climate change impacts detailed in the IPCC special report, such as increasing temperatures, sea level rise, and receding glaciers, are happening faster than we expected.

Speaking up for small states in attendance, Nepal’s President Bidhya Devi said that Nepal has “been bearing the brunt of disproportionate impact of climate change despite being a low carbon-emitting country… We feel as if we have been penalised for the mistakes we never made. It is incumbent on the international community to ensure that justice is done.”

4 December 2018

UNESCO, in partnership with the Norwegian GRID-Arendal Foundation, presents a new report, titled “Andean Glacier and Water Atlas: the impact of glacier retreat on water resources,” which details the consequences of glacier retreat on water availability and security for communities who depend on glaciers for drinking water, hydropower, agriculture, and other industries. Since the 1980s, when Andean glaciers were in a period of peak discharge, there has been less and less meltwater each year. This has huge negative impacts on communities who depend on glacial meltwater, and even more so during times of drought.

Precipitation trends suggest that snow cover will continue to decrease, along with temperatures rising 2-5 degrees Celsius in the tropical Andes and 1-7 degrees Celsius in the southern Andes. The report further estimates that even under moderate warming scenarios, low-altitude glaciers in the tropical Andes could lose 78 to 97 percent of their volume in the 21st century.

  • Peru, home to the largest number of tropical glaciers on the continent, has seen extremely rapid glacier retreat, with very few, brief intermittent periods of advancement.
  • Venezuela’s only remaining glacier will likely cease to exist by 2021.
  • Bolivia’s glaciers have lost more than two-thirds of their volume since the 1980s.
  • Colombia is also experiencing rapid glacier retreat; by 2050 the sole survivors will be the largest glaciers at the highest altitudes.
  • Ecuador’s glaciers have been subject to dramatic losses in the last 50 years.
  • Chile and Argentina are seeing accelerating melting among low-lying freshwater and tidewater glaciers in Patagonia and Tierra del Fuego.

5 December 2018

The World Health Organization (WHO) releases the COP24 special report: health and climate change. The report implicates anthropogenic climate change as the source of huge challenges for human health. The same industries who emit greenhouse gases, which warm the planet, are also responsible for emitting PM2.5, which harms human health. Within the public health and climate change conversation, glaciers receive a small but important cameo on black carbon. Black carbon, a by-product of inefficient combustion (from cookstoves, diesel engines, biomass, etc.) is second only to CO2 emissions in its global warming contribution. 

Not only is black carbon important on a global scale, but it also has impacts on regional climate systems. Black carbon works to accelerate glacier retreat in mountainous regions as well as the Arctic. As it settles, black carbon darkens a glacier’s surface, absorbing instead of reflecting heat, and inducing glacial melting.

Read more about black carbon on GlacierHub.

The Global Carbon Project reports that global CO2 emissions are projected to increase by 2.7 percent by the end of 2018. Following a brief stagnation in global CO2 emissions from 2014-2016, emissions rose by 1.6 percent. To limit warming to 1.5 degrees Celsius (or briefly overshoot it and come back down), global emissions need to be drastically decreasing, not increasing, and at current levels the world will certainly exceed this threshold by 2030.  

7 December 2018

COP24 Side Event – Mountain regions moving towards carbon neutrality

This side event’s keynote speaker, Eric Nanchen, is the director of the Foundation for Sustainable Development in Mountain Regions (FDDM). His talk covered climate change impacts and vulnerability of mountain regions, in the context of laying foundations for sustainable development. He also discussed the Mountain Research Initiative’s #VanishingGlaciers campaign, which is also being promoted at COP24. Deputy Secretary General of the Alpine Convention, Marianna Elmi, discussed steps that Alpine countries are taking toward climate neutrality, for example, coming up with a climate target system for 2050. 

10 December 2018

Newly released maps from NASA indicate that a group of four glaciers on the eastern coastline of Antarctica have been losing ice over the last decade. Since 2008, these four glaciers, which are located just to the west of the massive Totten glacier, have lost about 9 feet of their surface height. Prior to these findings, East Antarctica was thought to be much more stable than its western counterpart.

11 December 2018

COP24 Side Event – International Mountain Day – Mountain adaptation: Vulnerable peaks and people

On International Mountain Day, UN Environment releases two reports: Mountain Adaptation Outlook Series – Synthesis Report, and its more regionally focused counterpart, Outlook on climate change adaptation in the Hindu Kush Himalaya. The same day, in an UNEP press release, Joyce Msuya, Acting Executive Director at UN Environment says, “Mountain ranges are extremely complex ecosystems home to some of the most marginalized and vulnerable communities. It is critical that we focus on helping these communities adapt to changing climate in mountain regions.”

The synthesis report begins by framing the importance of mountain ecosystems, which cover 25 percent of the Earth’s landmass, house 15 percent of the world’s population, and provide essential ecosystem services to over half the world’s population. The report then goes on to call mountainous regions the “frontline of climate change.” Mountainous regions are subject to altitude amplification, whereby warming at high altitudes actually occurs at a faster rate than the global average, much like it does at the poles. Almost every mountain in the world is seeing substantial glacier retreat, which impacts ecosystems all the way downstream. In addition, the steep, sometimes unstable terrain leaves mountain communities more susceptible to floods and landslides. The synthesis report strives to capture regional differences in primary risk factors, climate change impacts, and current policy gaps in order to identify potential adaptation measures for each region.

The second report specifically targets the Hindu Kush Himalaya, and is actually part of a progressive series which has previously covered other mountainous regions around the world. The Hindu Kush Himalaya are of particular importance because it is already one of the most disaster-prone regions on Earth. Further, the report states this region could warm upwards of 4-5 degrees Celsius by 2100. The disproportionate warming effects of climate change at altitude, coupled with increased severity of precipitation events and the high probability of natural disasters in Hindu Kush Himalaya all work in tandem to make the region even more vulnerable to global warming.

12 December 2018

Side Event – IPCC Special Report on 1.5 Degrees, NDCs and Cryosphere: Pathways for Both High Urgency and Ambition

This event was focused on the IPCC Special Report, Global Warming of 1.5ºC, and working within the emissions constraints set by the report to minimize any further damage incurred by positive global warming feedbacks such as sea level rise and other impacts on mountainous and polar areas. Discussion was focused primarily on how to incorporate cryosphere considerations into the Nationally Determined Contributions (NDCS) for 2020 in order to minimize future risk and impact. 

During closing remarks for the COP24 High-Level Segment of the Talanoa Dialogue, the Secretary General makes note of three reports published in the past few days that “added to the long list of warnings signals.” Among them is the special WHO report on human health and climate change and NASA’s research showing signs of glacier melting in East Antarctica, which are both discussed above. He used these current events to show that we cannot ignore the rapidly accumulating effects of climate change, and to encourage countries to participate in successful policy-creation during COP24’s final days.  

 

Roundup: Glacier Thickness, Hydropower, and Mountain Communities

Measuring Glacier Thickness in Svalbard

From American Geophysical Union: “To this day, the ice volume stored in the many glaciers on Svalbard is not well known… This surprises because of the long research activity in this area. A large record of more than 1 million thickness measurements exists, making Svalbard an ideal study area for the application of a state‐of‐the‐art mapping approach for glacier ice thickness….we provide the first well‐informed estimate of the ice front thickness of all marine‐terminating glaciers that loose icebergs to the ocean.”

Read more about scientific advancements in measuring glacier thickness here.

Monacobreen glacier Svalbard on GlacierHub
The Monacobreen glacier, in Svalbard, calves into the Arctic Ocean (Source: Gary Bembridge/Flickr).

 

Hydropower in Iceland: Opinions of Visitors and Operators

From Journal of Outdoor Recreation and Tourism: “The majority of visitors are against the development of hydropower in Skagafjarðardalir. They believe that the associated infrastructure would reduce the quality of their experience in the region that they value for perceived notions of it being untouched and undeveloped. If the quality of their experience is reduced, so would their satisfaction with that experience.”

Read more about the views regarding the impact of a proposed hydroelectric plant on the tourist experience in Skagafjarðardalir here.

Skagafjörður, Iceland on GlacierHub
A picturesque view of Skagafjörður, one of the sites where the hydroelectric power plant has been proposed (Source: James Stringer/Flickr).

 

8 Experts Explain What Mountain Communities Need Most

From National Science Review:

“What happens [in the Third Pole] can affect over 1.4 billion people and have regional and global ramifications.” – Tandong Yao

“Researchers and the media tend to focus on big glaciers, but it’s the much smaller and much less glamorous glaciers and ice fields that are going to affect mountain communities the most.” – Anil Kulkarni

Read more about future difficulties mountain communities will face, and how they should be addressed here.

Tibetan village in the Himalayas on GlacierHub
A Tibetan village sits at the foot of the Himalayas, with Cho Oyo to the left. Mountain communities like this one are extremely vulnerable to climate change (Source: Erik Törner/Flickr).

Exception or Rule? The Case of Katla, One of Iceland’s Subglacial Volcanoes

Katla Volcano in Iceland on GlacierHub
Grasslands in the foreground, with Katla covered by clouds in the background (Source: Inga Vitola/Flickr).

A recent study in Geophysical Research Letters about Katla, a subglacial volcano in Iceland, revealed that Katla emits CO2 at a globally important level. Previously, Katla’s CO2 emissions were assumed to be negligible on a global scale.

In this study, conducted by Evgenia Ilyinskaya, a volcanologist at the University of Leeds, and her associate researchers, airborne measurements were carried out using gas sensors to obtain CO2 source and emission rates for Katla. In addition, the researchers used atmospheric dispersion modeling to identify the source of gas emissions and calculate gas emission rates.

A CO2 emission rate of 12-24 kilotons per day is considered significant on a global level. Ilyinskaya and coauthors’ measurements taken on the western side of Katla indicated significant CO2 flux levels in both 2016 and 2017. Also in 2017, the researchers identified another significant source of CO2 emissions, Katla’s central caldera.

Katla 1918 eruption on GlacierHub
Katla’s last eruption was in 1918 (Source: Creative Commons).

Emissions estimates that are both accurate and representative for subglacial volcanoes are challenging to obtain. According to the study, this is because these volcanoes are hard to access and “lack a visible gas plume.” The researchers noted that CO2 flux measurements are available for just two of Iceland’s 16 subglacial volcanoes, and these measurements indicate only modest emissions estimates. Further, these measurements were obtained by analyzing gas content dissolved in water, a method which likely underestimates CO2 flux. Ilyinskaya and her coauthors used a more precise estimate in this study than previous methods, such as the one discussed above.

Total CO2 emissions from passively degassing subaerial volcanoes are currently estimated at 1,500 kt/d, and CO2 flux is currently estimated at 540 kt/d. The results Ilyinskaya and the other researchers found indicate that Katla’s CO2 emissions would account for 2-4 percent of that total. However, they stipulated that subglacial volcanoes were underrepresented in the data collected to create this estimate. Measurements from 33 volcanoes were extrapolated to cover CO2 emissions of 150 volcanoes, but only three of the 33 were subglacial volcanoes.

Myrdalsjokull glacier covering Katla volcano on GlacierHub
View of the Myrdalsjokull glacier, which covers Katla (Source: Zaldun Urdina/Flickr).

Regarding Katla, Ilyinskaya and coauthors identified two possible implications of this information. First, Katla could be an exceptional emitter. Katla’s large size and recent heightened seismic activity make this possibility more plausible. But the researchers pointed out that measurements must be conducted at other subglacial volcanoes before this possibility can be corroborated.

A second possibility is that Katla’s CO2 emissions are representative of what other subglacial volcanoes emit. If this is true, estimates of CO2 emissions from subglacial volcanoes are grossly underestimated at present. Once measured properly, these volcanoes would make a much more significant contribution to global volcanic CO2 emissions. Currently, subaerial volcano CO2 emissions are assumed to be just 2 percent of anthropogenic CO2 emissions totals, but this could change with improved measurement practices.

Myrdalsjokull glacier above Katla volcano on GlacierHub
Atop the Myrdalsjokull glacier, with Katla beneath it (Source: Adam Russell/Flickr).

In the context of climate change, it is important that CO2 emissions from natural sources are adequately quantified alongside anthropogenic sources. As the results of this study suggest, subglacial volcanoes such as Katla could have emissions contributions that are more significant than originally thought. Ilyinskaya and her fellow researchers stressed the vital importance of conducting similar measurements at other subglacial volcanoes to ensure that their CO2 emissions are properly quantified in global estimates.