Washington is the second most-glaciated state in the United States, after Alaska. Mount Baker, located in the North Cascade Range, is an active stratovolcano that contains about 49 square kilometers of glaciers. The region is a popular skiing destination and the surrounding Skagit Valley provides a beautiful location from which to photograph glaciers.
Chris Pribbernow is an outdoor and sports photographer based in Washington. He recently captured the Skagit Valley and Mount Baker glaciers. Take a look at some of the photographs from his visits or see his other images from Washington State @PribbernowPhotography.
Glacier lake outburst floods (GLOFs) pose an immediate threat to locations in mountain regions where rising temperatures contribute to glacier melt. This risk makes it crucial that communities at risk to GLOFs develop early warning systems (EWS) to alert residents of impending danger. In order for EWS to be effective, gender needs to be prioritized. In a recent paper published by the International Center for Integrated Mountain Development (ICIMOD), Mandira Shrestha et al. evaluated flood early warning systems in Bhutan and found that many EWS exclude women, who are especially susceptible to natural disasters like GLOFs.
GLOFs, which are difficult to predict and devastating to local populations, occur when meltwater is suddenly released from a lake just below a glacier. When this occurs, large amounts of water rush down valleys, picking up debris. They can lead to many deaths and to extensive destruction of fields and property.
In total, Bhutan has 24 lakes which are capable of causing GLOFs. As temperatures rise, glacier melt increases, leading to exposed moraines and larger volumes of water. However, an EWS can help save lives during a GLOF, especially if it is combined with preparatory actions before a flood occurs.
In Bhutan, the EWS was first introduced in 1988 as part of the Hindu Kush Himalayan – Hydrological Cycle Observing System (HKH-HYCOS), a project developed by ICIMOD, national governments in the region, and the World Meteorological Organization. However, Shrestha et al. found that none of the current policies in Bhutan’s EWS address specific needs and experiences of women during natural disasters. In planning documents, women are described as victims, rather than presented as playing an important role in disaster risk management.
The Bhutan EWS contains four major elements, also found in other warning systems: risk assessment, monitoring and warning, dissemination and communication, and response capability. The Bhutanese government first prioritized flood early warning systems in 1994, following a detrimental GLOF, which killed 12 people, destroyed 21 homes, and washed away nearly 2,000 acres of land. Shrestha et al. point out that even a good warning system would not be fully effective in preventing such a tragedy if it fails to reach vulnerable populations like women, as well as other such populations including children, disabled people, and the elderly.
As Shrestha et al. explain, while women in Bhutan make up 49% of the population and legally have equal rights and access to education, public services, and health care, most women engage in household labor, while men dominate political work. The authors indicate that only 25 percent of women in Bhutan are involved in non-agricultural work. Extensive male out-migration in Bhutan, as elsewhere in the Hindu Kush Himalayas, leaves women to carry out the work in domestic agriculture. As a result, Bhutanese women are excluded from decision-making processes at community or larger scales.
This pattern is reflected in other nearby countries as well. One study done on disaster-affected people seeking mental health care in Bangladesh, which has the highest natural disaster mortality rate in the world, found that women have higher mortality rates in natural disasters, and are also extremely vulnerable in the aftermath of a natural disaster. For example, they are more likely to face food shortage, sexual harassment, and disease, among other issues.
Shrestha et al. describe how the social structure in Bhutan leaves women dependent on men for receiving disaster information, because these details are shared in public places, where women typically do not go. Many of the alerts are done through sirens, but some women cannot hear them as they are located in towns rather than rural areas. Even if women do receive the information, it is often too late. Due to cultural norms that restrict their freedom of movement when in public, women are frequently left waiting to ask for permission from men to take actions that can save their lives.
Gender-inclusive EWS emphasizes assuring that women receive early warnings, but also, more importantly, that they participate in decision-making processes. Without these features, early warning systems may prove inadequate to save the lives of women in natural disasters like GLOFs.
Learning by doing can be an effective educational tool. Irene Bollati et al. discovered this to be true while researching climbing as a way to educate students about earth science in the glacier-rich Italian Alps. Their findings were featured in a recent article in the Journal of the Virtual Explorer, in which they describe how climbing teaches young people about processes like weathering and glacial retreat.
For their research, Bollati et al. looked specifically at the Verbano-Cusio-Ossola Province in the western Italian Alps, where there is a long tradition of mountaineering. As the most northern province in Italy’s Piedmont region, the Verbano-Cusio-Ossola is located in a subduction zone in which the Eurasian and African plates collide. Mountain chains like the Alps are an ideal location for education, because they contain geosites, places where many geological and geomorphological processes are exposed in a relatively small area. By finding these locations on which to climb, younger generations can be inspired to learn and become more invested in the preservation of the site’s features.
Finding geosites typically has one of two goals, according to Bollati et al. The first is geosite conservation when the site is rare and at risk of degradation. The second is earth science dissemination in cases where the site is valuable for educational purposes. In the latter, it is important that the site’s usage for educational purposes not put its scientific integrity at risk. In their study, Bollati et al. focused on methodology to find the most valuable geosites which meet both goals.
Specifically, the researchers focused on a pilot educational project, in which they assessed 100 13 and 14-year-old students from four schools about 80 km from the study region. The project sought to identify the most suitable climbing locations and best mountain cliffs on which students could learn about earth science and geoheritage. According to Bollati et al., geoheritage includes earth features and processes that should be sustained, conserved or managed for their natural heritage value. To determine these regions, Bollati et al. relied on eight major criteria including accessibility, rock cliff quality, and the presence of evident and active hazards. In total, they analyzed 59 crags using the eight major criteria, further dividing those crags into sub-locations.
In total, the study pinpointed 14 sub-locations or “geodiversity” sites in the Verbano-Cusio-Ossola province best suited for hiking and climbing. Subduction-collision zones like the Alps are excellent examples of geodiversity sites due to the many different types of rocks found within narrow areas. “Geodiversity,” a term first introduced in 1993, can be understood as the equivalent of biodiversity for geology, according to a paper by Murray Gray. It includes all geological, geomorphological, and soil features. It also encompasses their properties, relationships, and systems, according to Bollati et al.
The researchers defined three categories of geodiversity: extrinsic geodiversity (geodiversity of a region in comparison with other regions), regional intrinsic geodiversity (within a region), and geodiversity of a single site. The best examples of these processes and resulting features are called “geodiversity sites.” The most valuable of these for geoconservation are referred to as “geosites” and form the “geoheritage” of a region.
In the Verbano-Cusio-Ossola province, students can observe several important signs of glaciation. For example, rock slopes along the Ossola Valley and in the tributary valleys demonstrate glacial modeling. In addition, the researchers used rock samples and virtual methods to introduce the students to the three major rock families, igneous, metamorphic, and sedimentary, as well as the geomorphology of the cliffs.
Bollati et al. also used videos of climbers along three selected routes to help students learn where climbers were finding foot- and hand-holds. The hope was that students would become curious and ask questions about how the rocks formed. However, the authors found that the videos served better as support than as a substitute for the hands-on learning about earth science that climbing provides. By physically climbing the peaks, students learn first-hand how different climates and rock types impact the Earth.
In their study, Bollati et al. confirmed that students can more effectively learn by doing, understanding earth science better by identifying the more suitable locations on which to climb. Their findings encourage future generations interested in geology and conservation to find inspiration while climbing mountains.
Indigenous Arctic and Subarctic communities face social and environmental challenges that could impact their traditional knowledge systems and livelihoods, decreasing their adaptive capacity to climate change. In a paper featured in Ecology and Society, Nicole Herman-Mercer et al. discuss recent research that took place during an interdisciplinary project called Strategic Needs of Water on the Yukon (SNOWY). The project focused on how indigenous communities in the Lower Yukon River Basin and the Yukon-Kuskokwim Delta regions of Alaska interpret climate change.
Global warming has had a significant impact on these regions, with mean annual temperatures increasing 1.7°C over the past 60 years, according to the study. Rising temperatures are predicted to further change water chemistry, alter permafrost distribution, and increase glacier melt. These changes have had a massive impact on the residents living in the Yukon River Basin and their indigenous knowledge, as well as on the basin itself. For example, the basin’s largest glacier, the Llewellyn Glacier, has had a major contribution to increased runoff.
With environments changing at an ever-rapid pace around the world, more studies have begun to focus on indigenous knowledge and climate change vulnerability. Scientists believe it is important to understand indigenous culture because indigenous knowledge informs perceptions of environmental change and impacts how communities interpret and respond to risk.
The focus of previous studies in the Arctic and Subarctic had been on older generations in the community, whose observations help shape historical baseline records of weather and climate. These records are frequently missing or incomplete. However, as Herman-Mercer et al. explain, the role of younger generations in indigenous Yukon communities is often overlooked, despite younger people driving community adaptation efforts in response to climate change. Additionally, Kusilvak County, Alaska, where Herman-Mercer et al. focused their study, has a median age of 21.9 years, which makes it the youngest county in the United States.
During the project, Herman-Mercer et al. studied four villages with populations under 1,000 people. These villages are home to the native Alaska communities of the Yup’ik and Cup’ik peoples, named for the two main dialects of the Yup’ik language. These indigenous communities are traditionally subsistence-based, with the availability of game and fish, such as moose, salmon, and seals, determining the location of seasonal camps and villages.
Herman-Mercer et al. interviewed residents to better understand the communities’ observations of climate change and relationship with the environment. For example, the Yup’ik and Cup’ik people traditionally believe in a reciprocal relationship between humans and the environment, which influences how they view natural disasters and climate change. Rather than seeing these events as naturally occurring, the communities believe that environmental events are punishment for improper human behavior. As a result, the Yup’ik and Cup’ik people have cautionary tales of past famines and poor harvest seasons caused by immoral behavior. These tales also contain information on how to survive hardships using specific codes of conduct.
Herman-Mercer et al. relied on three methods to obtain interview participants for the study. First, the researchers had local partners and facilitators recruit members of the communities who were seen as experts. Then a community dinner was held in order to introduce the research team and SNOWY to the Yup’ik and Cup’ik people. Lastly, the researchers used a “snowball” approach in which the team encouraged participants to recommend other people for the study.
Nicole Herman-Mercer explained to GlacierHub that all but two of the interviews were conducted in English. For the two remaining interviews, a translator was used. In order to avoid influencing answers, the researchers refrained from using the phrase “climate change” when speaking with the Yup’ik and Cup’ik people. The research team then sorted the participants into four cohorts based on their ages: Cohort 1 was comprised of Millennials (early 1980s to present), Cohort 2 of Generation X (early 1960s to early 1980s), Cohort 3 of Baby Boomers (1946-1964), and Cohort 4 of participants over age 65 (the point at which a community member becomes an elder).
The interviews demonstrated that all participants observed changes in the environment occurring over a number of years and across seasons. However, older and younger generations had different perceptions of environmental changes and alternate contexts in which to understand these changes, according to Herman-Mercer et al. For example, younger generations believed that the warmer temperatures are part of the norm, while older generations noted differences between current and past climate conditions. In fact, younger generations had to be specifically prompted on their thoughts on how climate has changed, while older generations were generally forthcoming about their views on how climate has changed throughout the decades. Younger generations tended to remark more on other changes related to climate, such as the diminished populations of game animals.
In addition, the reciprocal relationship pivotal to the Yup’ik and Cup’ik communities was interestingly not mentioned by the younger generations. Herman-Mercer told GlacierHub that she is not fully aware of the implications of this finding, but she understands that it will have significant meaning for the future. The relationship between the communities and the environment is still prevalent in the worldview of the Yup’ik and Cup’ik people, but it is manifesting differently within younger generations. For example, historical Yup’ik traditional rituals like giving water back to the Earth are not practiced as before, but the relationship is still part of the culture.
From a social perspective, the Yukon River Basin communities have undergone very large changes in a few short decades. In that time, many residents have gone from living in houses made from sod to modern homes with running water and electricity. Younger generations in particular have access to technology like smart phones.
Herman-Mercer told GlacierHub that even older generations are now hunting with the aid of GPS and benefiting from its use. As the study explains, this increased connectivity has occurred more dramatically in these indigenous communities than elsewhere in the United States. With the rising effects of climate change and evolving societal norms, it is unclear how the Yup’ik and Cup’ik people will continue to communicate between generations. However, the combination of the younger generations’ steps towards adaptation and the elders’ perspectives of cultural history and knowledge will be key in helping these communities adapt to climate change.
In the future, Herman-Mercer believes that technology can be used to spread indigenous knowledge and help communities cope with climate change. She has already witnessed residents taking to digital platforms to share their knowledge and awareness. Historically, the Yup’ik and Cup’ik people have had to adapt to the changing conditions of a harsh Arctic environment. By sharing indigenous knowledge using modern tools, older generations can further teach the younger generations how to cope with climate change.
Roundup: Glacier Surface Motion, Black Carbon & Skiing
Remote Sensing Measures Glacier Surface Motion
From ISPRS Journal of Photogrammetry and Remote Sensing: “For monitoring of glacier surface motion in pole and alpine areas, radar remote sensing is becoming a popular technology accounting for its specific advantages of being independent of weather conditions and sunlight… Synthetic aperture radar (SAR) imaging is a complementary information source which has the advantage of providing images all year long, with no limitations in terms of weather condition and imaging time. It can reliably collect data with a pre-defined temporal interval over long periods of time with a ground resolution meeting the demands of glacier monitoring. Additionally, active SAR sensors observe both the amplitude and phase information of the backscattered signal from the ground target.”
Read more about remote sensing in alpine areas here.
Effects of Black Carbon on the Tibetan Plateau
From Advancements in Climate Change Research: “The Tibetan Plateau (TP), which has an abundance of snow and ice cover, is referred to as the water tower of Asia. Melting snow/ice makes a large contribution to regional hydrological resources and has direct impacts on local society and economic development. Recent studies have found that light-absorbing impurities, which may accelerate snow/ice melting, are considered as a key factor in cryospheric changes. However, there have been few assessments of the radiative effects of light-absorbing impurities on snow/ice cover over the Tibetan Plateau. Flanner et al. (2007) coupled a snow radiative model with a global climate model (GCM) and estimated the anthropogenic radiative forcing by the deposition of black carbon in snow averaged 1.5 W m−2 over the Tibetan Plateau.”
From National Geographic: “Børge Ousland, now 54, teamed up with French adventurer Vincent Colliard, 30, for the Alpina Ice Legacy project. Over 10 years, the duo plans to ski across the world’s 20 largest glaciers in an effort to raise awareness about climate change. They crossed Alaska’s Stikine Glacier on their second expedition in May 2015, and in May 2016 they tackled the project’s third glacier, the St. Elias-Wrangell Mountains Range Ice Field. After 19 days and 267 miles in the field, [National Geographic] caught up with Ousland and Colliard in Alaska to talk suffering, partnership, and coming home alive.”
When people think of the Arctic, they often think of polar bears on melting sea ice, not of an area contaminated by pollutants. However, according to an article by Maria Papale et al. in the Marine Pollution Bulletin, findings of polychlorinated biphenyls (PCBs) in the Arctic demonstrate that ice can be a major transporter of pollutants in this remote region. The research team examined the concentration of PCBs in a fjord called Kongfjorden, located in Svalbard in Arctic Norway (79° N, 12° E), in order to understand how the Arctic is affected by pollutants. Given the impact these chemicals can have on human and animal health, the increase in ice melt due to climate change will have serious consequences for the release of these toxins.
PCBs are an important type of persistent organic pollutants (POPs); as such, they have a long lifetime in the environment, although they can be broken down by sunlight or some microorganisms. They are compounds once used heavily in the production of refrigerator coolants, electrical insulators and other items from 1929 until the late 1970s, when they were banned in the United States and elsewhere due to health concerns, particularly their carcinogenic effects. The presence of PCBs in Svalbard in the Arctic Basin indicates some form of long-distance transport because the Arctic is thousands of miles from industrial centers where PCBs are produced. Pollutants like PCBs are transported from regions in the northern mid-latitudes into the Arctic by the prevailing winds and ocean currents.
As Papale et al. explain, the PCBs deposited from the atmosphere accumulate on the snow and ice. This deposition has a drastic effect on the region, because PCBs that get trapped in the ice are ultimately released into the environment once the ice melts. For this reason, decades-old PCBs can enter rivers and oceans now, as glaciers melt; they are also emitted when PCB-containing materials wear out through use or when they are burned. In the Arctic, concentrations of PCBs are on average 0.2 ng/m3. Those concentrations have increased since the 1980s, after the banning of PCBs in the United States.
Once introduced into the food web, the fate of PCBs depends on which bacteria is present in the environment, since bacteria, such as Actinobacteria and Gammaproteobacteria, possess genetic and biochemical capacities for breaking down PCB pollution. Papale et al. gathered data on the occurrence of cold-adapted, PCB-oxidizing bacteria in seawater and sediment along Kongsfjord, a fjord located on the west coast of Spitsbergen, an island in the Svalbard archipelago. The fjord is fed by two glaciers, Kronebreen and Kongsvegen. The outer fjord is influenced by oceanographic conditions, while the inner fjord is influenced by large tidewater glaciers.
Higher concentrations of PCBs were observed in the water right next to the glacier (due to high flows of sediment and sea currents) or next to the open sea (likely due to water circulation inside the fjord). The higher concentrations of PCBs next to the glacier indicate the influence of glacial meltwater containing PCBs. Once the PCBs arrive in Svalbard Archipelago by long-range transport, they build up in the glaciers on Kongfjorden, sometimes by attaching to fine-grained particles, which are then incorporated into the ice. When the ice melts in the summer, the glacier meltwater containing PCBs flows into the fjord and could also freeze into sea ice in the winter. Sea ice transported from other regions also brings POPs to the region. For example, Arctic Ocean sea ice that forms near Siberia can contain pollutant-laden sediments; it is carried to Svalbard by currents, receiving depositions from the atmosphere as it travels. It can also contain heavy metals like lead, iron and copper, as well as organochlorides like PCBs or DDTs.
Once PCBs enter the waters of Kongsfjorden, they can be absorbed by plankton and other organisms at the bottom of food webs. They become concentrated in the tissues of the invertebrates that eat these organisms. As they pass up the food webs to organisms such as fish, and then to birds and mammals, the concentrations increase, through a process known as bioaccumulation. Recent research has found dangerous levels of these compounds in polar bears, a top predator. As advocacy organizations for these iconic animals have argued, these toxins represent an additional threat to the viability of the species, already challenged by the loss of icebergs and sea ice so critical to their survival. In this way, polar bears can provide testimony to the dangers of chemical pollution, as well as to the dangers of global warming, in the remote high Arctic.
In honor of International Mountain Day on Sunday, December 11th, GlacierHub is excited to share with you our most-liked photos on Instagram. You can follow us @glacierhub for more images collected by our authors. After all, who doesn’t love amazing photos of glaciers?
And don’t forget to check out more info on International Mountain Day, a global celebration of mountain life established by the United Nations General Assembly in 2003. This year’s theme is “Mountain Cultures,” celebrating diversity and strengthening identity. #MountainsMatter
Lack of access to health facilities is a massive problem facing developing countries. Zaheer Abbas et al. recently published a paper on the Karakoram Range in Northern Pakistan in which the communities have been relying on traditional methods for treating common physical ailments. Like many remote communities without access to modern health care, the Balti community have honed their traditional knowledge of local plants over the centuries using herbal treatments readily available to them in the Karakoram range. However, traditional knowledge is not well recorded in the region because medicinal plant concoctions are only passed down orally. This knowledge, if documented and shared, could inform other non-traditional medicine, according to Abbas et al. However, as R. Jilani et al. describe in another paper, if glaciers in Northern Pakistan start to melt, the reduction in the water resources could greatly affect the plants grown in the region, threatening the future use of Balti knowledge.
The Karakoram Range, a large mountain range that spans across Pakistan, Afghanistan, China, India, and Tajikistan, is one of the most glaciated areas outside of the polar regions and also one of the most botanically diverse. The range is home to the Biafo Glacier, which is the third largest glacier in the Karakoram and the fourth largest in Asia. For now, as Abbas et al. explain, the glaciers in the Karakoram Range are stable and not experiencing glacier melt like other regions. This is due to the very high altitude of the glaciers and the fact that temperatures remain cold throughout the year. However, a paper by Rajiv Chaturvedi et al. explains that in climate scenarios where carbon emissions continue to increase, we can expect melting of the Karakoram glaciers to occur at a rapid rate. The region and its glaciers have not previously been studied in depth due to the area’s remoteness, high altitude and harsh climate. Adding additional complications to future research is the fact that there is no weather station in the region, so temperature readings typically come from Skardu, 55 km away. This raises questions about the future impact of climate on the use of medicinal plants and traditional Balti knowledge.
For their Karakoram study, Abbas et al. interviewed 69 inhabitants of the region, including five herbalists, in order to understand how regional plants are used by the local communities for medicinal purposes. As Abbas et al. explain, many modern drug discoveries have been based on medicinal plants used by indigenous people. For this study, the team explored a total of 63 plant species, and with the help of the Balti people, categorized the plants into uses for 11 common diseases and disorders. They also looked at how effective the plants were at resolving those particular health issues based on a scale of 1 to 5 (5 being most effective). The common health issues ranged from anything from a common toothache to kidney stones. The study also showed the diversity of the plant parts used in the remedy, including flowers, seeds, leaves, and in some cases, the entire plant. The majority of the species studied were indigenous to the Tormik Valley due to its microclimate. The Tormik Valley is lush and fed by freshwater streams and springs.
Of the 63 species examined, three of them were particularly valuable due to their effectiveness, and each scored a 4 or 5 on the scale. Thymus linearis(a shrub with small dark purple blooms), commonly known as Himalayan thyme or common thyme and belonging to the Mint family, is used by the Balti people to treat abdominal pain and vomiting. Hippophae rhamnoides, commonly known as sea-buckthorn(a tree with bright orange seeds) is used to treat a multitude of disorders, including arthritis pain, eczema and urinary disorders. Convolvulus arvensis, a winding weed and relative of the morning glory, when ingested as a whole plant, is used to treat constipation.
Interestingly, Abbas et al. share that the upper and lower parts of Northern Pakistan have unique ethnobotanical traditional knowledge. The communities in the neighboring Skardu valley, located at the junction of the Indus and Shigar Rivers, for example, use the same Thymus linearis plant to treat colds and pneumonia. While they may use similar plants depending on the availability, communities sometimes use the plants in different ways. In some cases, they may use plants for activities beyond food and medicine, such as for building huts and fences.
Ethnobotany, the study of interactions between humans and plants, is especially important now as the documentation of traditional knowledge decreases with time. The Balti community demonstrates how important traditional knowledge of plants can be. The traditional knowledge cultivated within these communities can provide important data to help inform health care policy. However, if melting begins to affect the glaciers in the Karakoram Range, these plants may be entirely destroyed.
Roundup: Glacier-Fed Lakes, Remote Sensing, and Soil
Global Warming and Glacier-Fed Lakes
From Freshwater Biology: “Climate warming is accelerating the retreat of glaciers, and recently, many ‘new’ glacial turbid lakes have been created. In the course of time, the loss of the hydrological connectivity to a glacier causes, however, changes in their water turbidity (cloudiness) and turns these ecosystems into clear ones. To understand potential differences in the food-web structure between glacier-fed turbid and clear alpine lakes, we sampled ciliates (single-celled animals bearing ciliates), phyto-, bacterio- and zooplankton in one clear and one glacial turbid alpine lake, and measured key physicochemical parameters. In particular, we focused on the ciliate community and the potential drivers for their abundance distribution.”
Learn more about how global warming affects lakes here:
Glacier Remote Sensing Using Sentinel-2
From Remote Sensing: “Mapping of glacier extents from automated classification of optical satellite images has become a major application of the freely available images from Landsat. A widely applied method is based on segmented ratio images from a red and shortwave infrared band. With the now available data from Sentinel-2 (S2) and Landsat 8 (L8) there is high potential to further extend the existing time series (starting with Landsat 4/5 in 1982) and to considerably improve over previous capabilities, thanks to increased spatial resolution and dynamic range, a wider swath width and more frequent coverage.”
From Journal of Ecology: “Plant–soil interactions are temporally dynamic in ways that are important for the development of plant communities. Yet, during primary succession [colonization of plant life in a deglaciated landscape], the degree to which changing soil characteristics (e.g. increasing nutrient availabilities) and developing communities of soil biota influence plant growth and species turnover is not well understood. We conducted a two-phase glasshouse experiment with two native plant species and soils collected from three ages (early, mid- and late succession) of an actively developing glacial chronosequence ranging from approximately 5 to <100 years in age.”
Learn more about the impact of soil during glacier succession here:
From 2001 to 2014, climate scientists observed a “hiatus” or pause in global warming. It is an issue that has led to much discussion in the scientific community and among climate skeptics who see the trend as an indication that global warming does not exist. According to a paper published by Fyfe et al., the word “hiatus” is not fully accurate. Instead, instrument data shows a slowdown or deceleration (as opposed to a full halt) of global warming at the beginning of the 21st century. Glaciers are key in helping us understanding the global warming slowdown.
In a recent article, Wenling An et al. describe how the glaciers of the Tibetan Plateau show evidence of the recent warming slowdown. Known as the “Roof of the World,” the Tibetan Plateau spans 1,565,000 square kilometers and is the origin of the Indus, Mekong, and Yangtze Rivers. Due to its large size and location near the tropics, the plateau is one of the most ecologically diverse alpine regions in the world. Therefore, the Tibetan Plateau’s response to climate change has been studied extensively, with researchers relying on both meteorological and paleoclimate data.
Most studies to date have taken place in the more accessible eastern and central parts of the Tibetan Plateau, where there are a greater number of meteorological stations. Meanwhile, the northwestern part of the plateau remains remote and formidable. Thus, data gathered in the northwestern plateau continues to be sparse and collected during shorter timeframes. But the northwestern area has an important connection to the Asian monsoon season and mid-latitudes, recently prompting scientists to focus increased attention on gathering higher resolution data from the area. For one, the Tibetan Plateau plays an important role in the Asian monsoon season by acting as a heat source in the summer and a heat sink in the winter, according to an article by Hongxu Zhao and G.W.K. Moore.
Interestingly, the new data collected by An et al. revealed that the eastern and northwestern parts of the plateau have experienced entirely different temperature trends since the beginning of the 21st century. The eastern part shows increased warming during that period, while the northwestern part shows no warming.
In their research, An et al. describe the usefulness of using ice cores (drilled samples of ice from a glacier) to detect this phenomena in climate data. For example, ratios of stable isotopes (forms of the same element with a different number of neutrons) found in ice cores provide information that informs us about past climate conditions.
Studies were done on ice cores taken from the Tibetan Plateau examining the relationship of a particular variation of the amount of an oxygen isotope (δ18O) with precipitation and air temperature. The precipitation on the plateau was captured within the ice core as snow, which then converted to ice. The data demonstrated a positive correlation. This means the higher the concentration of δ18O, the higher the temperature of the air when the water evaporated.
In situations of higher δ18O, the research indicates that the air temperature was higher at the time the snow formed. Aside from temperature, the effect of seasonality and the precipitation amount were also examined to understand the relationship of the δ18O concentrations. Through statistical t-tests, An et al. concluded that seasonality and the precipitation amount did not have an effect on the concentration as temperature does. The results indicate that the temperature is the factor influencing the concentration of δ18O, rather than other factors.
The authors of the study drilled ice cores at Chongce Glacier on the northwestern part of the Tibetan Plateau. They looked at samples approximately 60m long and 6000m above sea level, focusing on the δ18O in the ice cores. The team’s conclusions were consistent with other studies of the area, showing that the levels of the isotope increased significantly in the 1990s, and remained high until 2008, when the δ18O levels started to show a steep decline in concentration from 2009 to 2012. This demonstrates that temperature increased significantly until 2008, when the increases in temperature slowed. This research matches two other ice cores taken from the area, as well as instrument data, demonstrating that the Chongce ice cores provide accurate information about past climate. This data further matches global trends.
Temperature has the largest effect on regulating the state of the Tibetan Plateau. As temperatures increase, melting of the glaciers on the plateau increases. The state of the glaciers on the northwestern part of the plateau has been largely stable since the beginning of the 21st century, likely due to slowed warming in the area. Tibetan Plateau glaciers tell us a lot about the pace of global warming and will continue to be a key tool in understanding how the Earth responds to changes in temperature.
Most people think of algae as the bothersome green stuff that grows on the tops of ponds and needs to be removed from the inside of fish tanks, but algae also provides clues about the environment. The response of Harmful Algal Blooms (HABs) to climate change, for example, provides evidence that some algae are extremely efficient environmental adaptors.
HABs are formed when colonies of algae living in fresh or saltwater grow out of control and begin producing toxic effects that can threaten the health and lives of animals and humans. According to NOAA, they have occurred in every coastal state in the United States and are increasing in frequency due to rising temperatures associated with climate change. As a result, HAB responses to climate change, including changes in pH and CO2, have been increasingly studied.
These responses include the expansion of the blooms into larger areas and an increased release of toxic poisons with warming temperatures. In a recently published paper, Mardones et al examine a special type of algal bloom found to be an expert adaptor to climate change. This strain of algal blooms called Alexandrium catenella occurs in highly variable fjord systems in southern Chile.
These Chilean fjords have had to respond to fluctuations in CO2 and pH. They experience huge freshwater inputs from Patagonian ice fields and heavy precipitation events. When dissolved in water, CO2 forms carbonic acid, which has a low pH. Therefore, levels of CO2 and pH are inversely correlated. As CO2 increases due to climate change, algal blooms in the fjords produce more Paralytic Shellfish Toxin (PST). This toxin could have long-term effects on the fish population and therefore the entire food web and ecosystem in the fjord.
In an article by Pedro Costa, he describes how these neurotoxins can have a lasting impact: poisoned fish can be consumed by seals and humans, causing health issues or even death. As we expect CO2 to continue to rise, it is very likely harmful algal blooms like the ones in Chile will produce more PST, leading to more fish kills, disturbed ecosystems in the fjords, and possible human health issues.
During their research, Mardones et al explored six levels of CO2/pH and two light conditions to examine how the algal blooms react. The scientists identified key differences in the waters in the fjord closest to the melting ice fields and the waters in the fjord further offshore. The near-shore water in the fjord experiences the largest impact of the freshwater inputs from the ice fields. The freshwater means that the upper layers of the water are much less salty compared to lower layers. This creates an intense halocline (stronger layers of differences in salinity) in the water column. Strong winds in the region mix the layers, which produce highly fluctuating differences in carbonate chemistry. As Patagonian glaciers continue to melt, even more freshwater will be introduced into the fjords, which will continue to change the conditions of the water.
On the other hand, the more stable offshore waters have CO2 equilibrium with the atmosphere. The main environmental driver offshore is human-caused ocean acidification. As CO2 emissions increase in the atmosphere, it dissolves in oceans and lowers the pH of the water. For most species, this causes huge problems, but certain types of algal blooms are able to adapt to these conditions.
Previous studies done by Tatter et al. show that a type of the same algal bloom from Southern California have previously changed their physiological responses due to changing pCO2/pH. Under higher CO2 conditions, production of Paralytic Shellfish Toxin increased. In 2015, there was an unprecedentedly large algal bloom that stretched from Central California to the Alaskan peninsula.
Mardones et al. found similar results in the Chilean algal blooms by examining the strains of the bloom under lab conditions. The blooms had been previously harvested years before and kept in culture. They analyzed these HAB responses to changes in pH and CO2. While they had optimal physiological performance at near-equilibrium levels of pH/CO2, the algal blooms showed an ability to adapt to changing conditions. They found that the blooms are in fact able to adapt their cell size based on the pH/ CO2 levels. In conditions with high pH/low CO2, the blooms adapted to a smaller cell size. In conditions with low pH/high CO2, their cell size increased, which means they are able to change their shape to not only survive changing conditions, but to thrive in them. In low CO2, high pH could increase chain formation (they could increase their swim speed to maintain their location without being moved in the current).
These factors, in addition to others, contribute to the resiliency of the harmful algal blooms in changing conditions, demonstrating they are expert adaptors to climate change.
When we think of imaginary mountains, we often think of dream-like peaks and impossible journeys. Throughout history, painters, writers, and adventurers have portrayed mountains as powerful illusions.
In The Writings of Henry David Thoreau, Thoreau captures the ethereal qualities of mountains that inspire such human flights of fancy:
“I lost myself quite in the upper air and clouds, seeming to pass an imaginary line which separates a hill, mere earth heaped up, from a mountain, into a superterranean grandeur and sublimity…unhandselled, awful, grand. It can never become familiar; you are lost the moment you set foot there. You know no path, but wander, thrilled, over the bare and pathless rock, as if it were solidified air and cloud.”
Be inspired by this collection of imaginary mountains from artists around the web.