Science

The Restlessness of Cotopaxi: A “Benevolent” Eruption

Posted by on Aug 17, 2017 in All Posts, Communities, Featured Posts, News, Science | 0 comments

The Restlessness of Cotopaxi: A “Benevolent” Eruption

Spread the News:ShareOn August 14, 2015, Ecuador’s glacier-capped Cotopaxi erupted for the first time since the 1940s. A billowing plume of ash rose early in the morning and grew through the day, reaching heights of over three miles. Two small eruptions rained ash on the southern outskirts of Quito, Ecuador’s capital 45 kilometers from the volcano. These dramatic events rattled the country and punctuated a period of seismic and low-level volcanic activity that lasted from April to November 2015. Recently, scientists at Ecuador’s Instituto Geofísico Escuela Politécnica Nacional (IGEPN) analyzed both the physical properties of the episode and the institutional and community responses of this “dry run,” yielding information that will help Ecuador prepare for future events. Lead author and IGEPN geologist Patricia Mothes told GlacierHub that among the most important lessons learned from the period of restlessness were that “changes can occur very rapidly,” and that certain seismic trends and deformation of the volcanic cone will act as precursors to actual eruption. The report found that over the seven months of earthquakes, degassing, ground deformation, glacial melting and plumes towering over the landscape, the activity level of the episode actually remained relatively low, at two out of eight on the Volcanic Explosivity Index. Nevertheless, the impacts of the activity were manifold. Heat from the rising magma, in tandem with the layer of dark ash that formed on the glaciers, increased melting and formed new crevasses. People donned masks to avoid breathing in the ash, which damaged crops, sickened livestock, and lowered visibility on the roads for people in transit across the country. Some residents hastily sold their land and livestock or abandoned them entirely. The net effect was to depress the local economy. With this geophysical unrest came unrest to those living near the volcano. The controversial President Rafael Correa declared a state of emergency, and thousands of residents of nearby villages evacuated to safer areas. After weeks to months of displacement in shelters and other towns, some returned to their homes, but recovery was slow and incomplete. In addition to economic harm, the volcanic activity had psychological dimensions. The Atlantic reported that people living in the risk zone experienced sleeplessness, anxiety, depression, and Post Traumatic Stress Disorder. The most intense threat to Ecuadorians was the potential of lahars, slurries of mud and melted snow and ice that can flow for tens of miles and devastate landscapes. The geologic record shows that in each major eruption, most recently in 1877, Cotopaxi has spawned major lahars on each of its flanks. During the 2015 event, glacial melt formed small lahars that sometimes covered the road to the volcano. In the event of a more major eruption, glacial outburst floods could occur, according to Mothes. “If impacted by hot pyroclastic flows that would come out of the summit crater and careen down the steep flanks, the glaciers would be greatly eroded, ripped up, and much internal glacier water would likely be released,” she told GlacierHub. During the eruption of 1877, between five and ten meters of ice melted, and giant lahars formed. In the event of an eruption in the future, “the only mitigation scheme is to have people go to higher ground, out of the areas to be potentially affected by lahars,” said Mothes. Communication surrounding the eruption events at the science-society interface was fraught, according to the IGEPN report. Though the agency released three updates daily, misinformation spread broadly through social media, causing panic. In response, emergency services and the IGEPN formed a “vigía” (“look-out” in Spanish) network of observers near the volcano, who disseminated observations of Cotopaxi on...

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Glacial Change in China’s Central Asia

Posted by on Aug 16, 2017 in All Posts, Experiences, Featured Posts, Science | 0 comments

Glacial Change in China’s Central Asia

Spread the News:ShareThough I lived in China’s Xinjiang Uyghur Autonomous Region for almost two years, it was only when I was in the heart of the Tian Shan mountains, my motorcycle meandering its way around fallen rock, sheep herds and horses, that I felt truly at home. Just a few hours outside of the city of Shihezi, inspiring peaks soared over 4000 meters. Though I had no scientific data to support my feeling that these stunning vistas were impermanent, over the course of my stay there were fewer and fewer clear days to see the cresting glacier-capped peaks from my apartment window. The haze even began to influence my weekend trips deep into the mountains, sometimes choking off the views far outside of the city. There is too much pollution in these mountains, not like when I was a child— a common refrain that echoed among many Kazakh and Mongol herders who made their home there. In a recent article in the journal of Arctic, Antarctic, and Alpine Research, Baojuan Huai and a team of Chinese researchers use remote sensing to put scientific data in the place of the herders’ and my own perceptions. The glaciers of the Tian Shan— the impressive mountain range that historically has divided the region’s agrarian oasis-states to the south and nomadic communities to the north— are in danger of disappearing. The authors demonstrate that in the Chinese Tian Shan, the total area of the glaciers studied has decreased by 22 percent over a fifty year period. The data also shows that glacier retreat is a variable within different regions of the Tian Shan— the result of a convergence of factors both human-caused and natural. China is home to a baffling 46,377 glaciers. The Xinjiang Uyghur Autonomous Region contains 18,311 of them. The Tian Shan, which cuts across Xinjiang into Kazakhstan and Kyrgyzstan, boasts the largest number of glaciers in northwest China. These glaciers provide invaluable solid reservoirs to agriculture, animal husbandry, and industry in the region. When considering the Tian Shan range alone, the glacial loss will continue to have a severe impact on the livelihoods and ecology of Xinjiang, according to Weijun Sun, one of the paper’s authors. “Warming temperatures are causing a real reduction to glaciers across China, and ablation is occurring constantly, negatively impacting regional ecology,” he said in an interview with GlacierHub. To acquire data for so many glaciers, the team utilized remote sensing technology, which relies on satellites to monitor different sites, using automated glacier mapping technology to distinguish glaciers from other features. Remote sensing alleviates many of the difficulties typically faced in conducting research on glaciers, which are often remote and difficult to access, according to Sun. “Remote sensing is a fantastic tool, expanding the scope of what we are capable of measuring. With this technology we can now measure things like the amount of reflectance coming from under the surface, or the temperature at the base,” he stated. For the study, the team selected glaciers that covered a range of variables: glaciers large and small, debris-covered and debris-free, and at high and low elevations were all represented. The research shows that over the period studied, 182 Tian Shan glaciers disappeared, and several large glaciers divided into multiple small glaciers. The percentage of area reduction tended to be higher in small glaciers than in large glaciers, with small glaciers more likely to shrink significantly or disappear entirely. Glaciers across the Tian Shan experienced a real loss over the period studied, but the rate of change between regions within the mountain range showed significant variability. While glacier loss in one region...

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Photo Friday: The Shrinking Patagonian Icefield

Posted by on Aug 11, 2017 in All Posts, Featured Posts, Images, Science | 0 comments

Photo Friday: The Shrinking Patagonian Icefield

Spread the News:ShareTypically obscured by cloud cover and mist, it is difficult to study the glaciers of the Southern Patagonian Icefield from space. However, on April 29, May 1, and May 24, 2016, NASA satellites captured clear images of the glaciers. Compiled into striking mosaics, this data reveals a great deal about the shrinking icefield. For example, the mosaics obviate the differences between the eastern and western parts of the icefield. Heavy precipitation on the landscape west of the icefield keeps the terrain green and lush, while the eastern regions of retreat are characterized by bare, brown rock. Glacial flour, a fine sediment produced when ice grinds over of bedrock, colors the proglacial lakes a distinct turquoise. Enjoy observing the Patagonian Icefield through the images below.             Spread the...

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Roundup: Green Development, Glacier Reduction, and Psychiatry

Posted by on Aug 7, 2017 in All Posts, Featured Posts, News, Roundup, Science | 0 comments

Roundup: Green Development, Glacier Reduction, and Psychiatry

Spread the News:ShareGreen Development in Patagonia From Project Muse: “This paper examines how Southern Andean Patagonia has been increasingly incorporated within networks of global capital since the 1990s. This remote region has become an iconic center for green development in Latin America. The article develops the argument that a regional territorial imaginary has facilitated this recent shift towards green development across the resource domains of land conservation, hydropower, and forestry. The discussion addresses the different ways in which forests, waterways, and protected areas (public and private) have been integrated into a hegemonic vision promoting eco-regionalism among state, corporate, and civil society actors.” Read more about Southern Andean Patagonia here.   Glacier Reduction in Tibetan Plateau From AGU Publications: “In this study, we focused on light-absorbing impurities (LAIs), including black carbon, organic carbon, and mineral dust in glacial surface snow from southeaster Tibetan glaciers. This study showed the concentrations of LAIs, and estimated their impact on albedo reduction. Furthermore, we discussed the potential source of impurities and their impact to the study area. These results provide scientific basis for regional mitigation efforts to reduce black carbon.” Learn more about the light-absorbing impurities here.   Combat Psychiatry of Indian Armed Forces From Science Direct: “Indian Armed Forces have been engaged in various combat duties for long. The adverse effect of prolonged and repetitive deployment of troops in these highly stressful environment leads to many combat stress behaviors as well as misconduct behaviors. Preventing, identifying and managing these disruptive behaviors are an essential part of combat psychiatry within the larger domain of combat medicine. Indian Armed Forces have a well-oiled mechanism to handle these issues and military psychiatrists are deeply engaged in providing holistic mental health care to the esteemed clientele.” The article mentions the Siachen Glacier (where India and Pakistan meet) as one of the sites in the study. Learn more about the hardships faced by the Indian Armed Forces here. Spread the...

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When Rivers Meet the Sea: Carbon Cycling in the Gulf of Alaska

Posted by on Aug 3, 2017 in All Posts, Featured Posts, Science | 0 comments

When Rivers Meet the Sea: Carbon Cycling in the Gulf of Alaska

Spread the News:ShareWhen rivers meet the sea, the sediment they carry becomes mixed into the ocean, where it makes quite a splash, biogeochemically speaking. In the subarctic North Pacific Ocean, for example, iron-rich sediment delivered from the continental margin spurs a wintertime phytoplankton bloom over 900 kilometers offshore. The presence of these terrigenous particles is felt up the food chain— the higher levels of iron in the water support larger diatom populations, which means more snacking for copepods, a type of zooplankton. In the Gulf of Alaska, glacial meltwater is an important source of terrestrial particles. A recent study by Jessica Turner, Jessica Pretty, and Andrew McDonnell optically measured particles in the northern Gulf of Alaska, an area with extensive glacial inputs. This technique allowed the researchers to collect massive amounts of data with minimal lab work, maximizing the area they could survey, Jessica Pretty told GlacierHub. Their instrument measured a range of particle sizes, from some too small to be seen by the naked eye to others as large as paper clips. Pretty and her coauthors found that in the Gulf of Alaska, particle concentrations are denser in two main places: where glaciers and rivers flow into the Gulf, and offshore, near the continental shelf break, where they are buoyed by waves, currents and tidal action. These small particles wield great influence, increasing biological productivity at the shelf break. “The Gulf of Alaska is an interesting region,” said Pretty. “It has major freshwater input seasonally from melting glaciers and river runoff that eventually joins with Pacific waters and makes its way toward the Arctic.” The recent findings illuminate particle distribution in the northern Gulf of Alaska, yielding clues about how climate change may affect carbon cycling in the Gulf and parallel ocean systems. Beyond local significance to the Gulf of Alaska ecosystem, the influence of these river-borne terrestrial particles scales up— globally, such sediment inputs impacts the carbon cycle, which regulates climate. The bits of rock Pretty tracked in the Gulf of Alaska are essentially tiny bundles of carbon, and when these bundles sink in the ocean, they drive what scientists have termed the “biological pump,” the process by which the ocean cycles organic and inorganic carbon, and sequesters carbon dioxide in the deep ocean. Because carbon dioxide is constantly exchanged between the upper layers of the ocean and lower levels of the atmosphere, concentrations become equal in the shallow ocean and low atmosphere over time. However, sinking particles remove carbon from this exchange. “The biological pump allows the ocean to store more carbon than it would be able to just from equilibration,” explained Pretty. The ocean absorbs a quarter of the carbon dioxide released into the atmosphere each year, and so as carbon is pumped into the atmosphere, levels in the ocean increase in tandem. This leads to ocean acidification, which threatens many marine species. However, terrestrial carbon sequestration practices, like soil conservation and wildfire suppression, may be an important element of climate change mitigation. As global climate warms and glaciers melt, higher glacial inputs will carry more sediment to the Gulf of Alaska and analogous ecosystems around the world. These minute particles will ramp up the global biological pump, increase carbon sequestration, and lead to a myriad of impacts yet unknown. In addition, seasonal changes, like an earlier springtime, may also spur earlier phytoplankton blooms, changing the dynamics of life in the sea. Through the movement of minuscule specks of rock, the Gulf of Alaska, and ultimately the whole ocean, will change. Spread the...

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Roundup: Crack, Flood, Fight

Posted by on Jul 31, 2017 in All Posts, Featured Posts, News, Policy and Economics, Roundup, Science | 0 comments

Roundup: Crack, Flood, Fight

Spread the News:SharePetermann Crack Develops From Grist: “Petermann is one of the largest and most important glaciers in the world, with a direct connection to the core of the Greenland ice sheet. That means that even though this week’s new iceberg at Petermann is just 1/500th the size of the massive one that broke off the Larsen C ice shelf in Antarctica earlier this month, it could eventually have a much bigger effect on global sea levels. Scientists believe that if Petermann collapses completely, it could raise the seas by about a foot.” Read more about the potential collapse of the Petermann here.   Glacial Outburst Flood Rages in Iceland From The Watchers: “A glacial outburst flood started in Iceland’s Múlakvísl river around midnight UTC on July 29, 2017. Electrical conductivity is now measured around 580µS/cm and has increased rapidly the last hour, Icelandic Met Office (IMO) reported 10:14 UTC on July 29. Increasing water levels of this river are an important indicator of Katla’s upcoming volcanic eruptions.” Read about safety concerns associated with the flood here.   Conflict in the Himalayas From The New York Times: “The road stands on territory at the point where China, India and Bhutan meet…The standoff began last month when Bhutan, a close ally of India, discovered Chinese workers trying to extend the road. Now soldiers from the two powers are squaring off, separated by only a few hundred feet. The conflict shows no sign of abating, and it reflects the swelling ambition— and nationalism— of both countries. Each is governed by a muscular leader eager to bolster his domestic standing while asserting his country’s place on the world stage as the United States recedes from a leading role.” Learn more about the geopolitics of this standoff here.   Spread the...

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