Roundup: Project BlackIce, Larvae, and Nature Study Retraction

Project BlackIce Examines Microbes and Glacial Albedo

From Project BlackIce: “Algae can protect themselves before damaging UV-radiation by darker pigmentation which results in a darkening of the surface which is increasing the availability of liquid water, hence again the growth of microbial communities. This biologically induced impact on albedo is called ‘bioalbedo’ which has never been taken into account in climate models. So far we have most information on bioalbedo on arctic glaciers which is quite a shame that literally nothing is known about alpine glaciers. The aim of this interdisciplinary study is a quantification and qualification of organic and inorganic particles on an alpine glacier (Jamtalferner).”

Learn more about Project BlackIce here.

Photo of Project BlackIce logo.
The Project BlackIce logo (Source: Project BlackIce).

Patterns in Larvae Size in Glacial Streams

From Schütz & Füreder: “Glacially influenced alpine streams are characterized by year-round harsh environmental conditions. Only a few, highly adapted benthic insects, mainly chironomid larvae (genus Diamesa) live in these extreme conditions. Although several studies have shown patterns in ecosystem structure and function in alpine streams, cause–effect relationships of abiotic components on aquatic insects’ life strategies are still unknown. Sampling was performed at Schlatenbach, a river draining the Schlatenkees (Hohe Tauern NP, Austria)… This is the first study to show that harsh conditions in these environments (low temperatures, high turbidity and flow dynamics) may exclude many taxa, but favor other, highly adapted species, when their essential needs (food quality and quantity) are guaranteed.”

Learn more about the study here.

Image of the Diamesa cinerella larva
The Diamesa cinerella larva. Numbers represent the sites where measurements were taken (Source: Schütz & Füreder).

 

Nature Study on Asian Glaciers Retracted

From Nature: “In this article, I estimated net glacial melt volumes on the river-basin scale from long-term precipitation and temperature records (1951–2007), taking into account the various mass contributions from avalanching, sublimation, snow drifting and so on… I estimated the second meltwater component (the additional contribution from glacier losses) as −0.35 to −0.40 metres water-equivalent per decade based on a global compilation of long-term mass-balance observations (from table 2 in ref. 32 of the Article). In this table, losses are described as ‘decadal averages (millimetres water equivalent)’ but the units are actually intended to be decadally averaged annual values. Hence, the loss components of total meltwater that I used in my calculations are too small and the summed meltwater volumes reported here should be larger. Asia’s glaciers are thus regionally a more important buffer against drought than I first stated, strengthening some of the conclusions of this study but also altering others. I am therefore retracting this article.”

Learn more about the retraction here.

A figure from the retracted study.
A figure from the retracted study (Source: Nature/Twitter).

 

 

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Roundup: Pakistan’s Glaciers, Jobless Sherpas, Ancient Rivers

This Week’s Roundup:

Pakistan has more glaciers than almost anywhere on Earth. But they are at risk.

From The Washington Post:

Mohammad Idrees, 11, eats ice that has been hacked from the mountain peaks by vendors and offered for sale along a road in the Chitral Valley last month (Source: Insiya Syed /For The Washington Post).

“For generations, the glacier clinging to Miragram Mountain, a peak that towers above the village, has served as a reservoir for locals and powered myriad streams throughout Pakistan’s scenic Chitral Valley. Now, though, the villagers say that their glacier — and their way of life — is in retreat….

With 7,253 known glaciers, including 543 in the Chitral Valley, there is more glacial ice in Pakistan than anywhere on Earth outside the polar regions, according to various studies. Those glaciers feed rivers that account for about 75 percent of the stored-water supply in the country of at least 180 million.

But as in many other parts of the world, researchers say, Pakistan’s glaciers are receding, especially those at lower elevations, including here in the Hindu Kush mountain range in northern Khyber Pakhtunkhwa province. Among the causes cited by scientists: diminished snowfall, higher temperatures, heavier summer rainstorms and rampant deforestation.”

Read the full story here.

 

Sherpas Denied Summit Certificates

From The Himalayan Times:

Climbers ascending the Lhotse face on Mt Everest. Photo credit: Garrett Madison
Climbers ascending the Lhotse face on Mt Everest (Source: Garrett Madison/THT)

“The Department of Tourism, under the Ministry of Culture, Tourism and Civil Aviation, has refused to award high-altitude workers summit certificates, citing a clause of the Mountaineering Expedition Regulation that bars them from obtaining government certificates….

He said DoT couldn’t issue certificates to Sherpas as per the existing law, claiming that high-altitude workers are not considered a part of the expedition as per the Mountaineering Expedition Regulation that was framed in 2002. ‘The regulation considers only those who obtain climbing permit by paying royalty to the government as members of an expedition’ [Laxman Sharma, Director at DoT’s Mountaineering Section, told THT].

This is the first time in the country’s mountaineering history that Sherpas have failed to obtain government certificates despite successfully scaling mountains.”

Read the full article here.

 

Ancient Rivers Beneath Greenland Glacier

From Live Science:

Image from the research article published in Nature (Source: Cooper et al, 2016/Live Science).

“A network of ancient rivers lies frozen in time beneath one of Greenland’s largest glaciers, new research reveals.

The subglacial river network, which threads through much of Greenland’s landmass and looks, from above, like the tiny nerve fibers radiating from a brain cell, may have influenced the fast-moving Jakobshavn Isbrae glacier over the past few million years.

‘The channels seem to be instrumental in controlling the location and form of the Jakobshavn ice stream — and seem to show a clear influence on the onset of fast flow in this region,’ study co-author Michael Cooper, a doctoral candidate in geography at the University of Bristol in the United Kingdom, told Live Science. ‘Without the channels present underneath, the glacier may not exist in its current location or orientation.”

Full story continued here.

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Photo Friday: Nunataks in Antarctica

Nunataks are small volumes of rock that emerge above ice sheets and glaciers. They are isolated from mountain ranges and are often easier to access. This makes them particularly useful to geologists as a source of data about bedrock. The photos here shows the view of nunataks in Antarctica taken by Euphro and Chantal, who are both nunatak scientists and photographers.

Photo Friday highlights photo essays and collections from areas with glaciers. If you have photos you’d like to share, let us know in the comments, by Twitter @glacierhub or email us at glacierhub@gmail.com.

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Yes, Glaciers Melt, But Do You Know How?

https://www.flickr.com/photos/logicalrealist/14494532650/in/photolist-nWJPeD-nWJQTR-9Y9Any-nWryPM-bDWXVm-6VtJ1d-9YpxJ2-nYw5Cr-o5Qgzm-nYvYLX-cJqHgJ-hKxWT-nWAuQu-wAom3-8uqaNk-hxSgW-nWrmyp-nEcxKK-528Y2j-nYw5Rc-cwXHRy-9YssPU-9Y9Ajd-9YpxeB-cwXJdL-cwXJTq-deJjfx-9YssXL-9Y9zqY-9YpxCc-9Ysszu-wAmcR-wAoTs-9YJcob-cwXKuw-9Y9ApQ-9Y9zR5-9Y6F9F-acuhzL-cJqCA3-8wxq4K-9YsspY-9YJcmG-9Ypwxn-9XLdsz-9Y9zy1-prjm3-9YssN9-9YpxAg-ca1XX5/
Perito Moreno Glacier calving (Sean Munson/Flickr)

Have you ever wondered how glaciers melt? Do they melt from underneath? Top down? Maybe from all around at once? From the center outward? How fast do they melt? Do all glaciers melt? These are questions scientists’ wonder too, and they’ve been getting some interesting answers.

Virtually every glacier on earth melts each year during the summer, but as long as winter snow accumulation is equal to or greater than that summer melt, a glacier is considered to be stable or growing. If the glacier melts more in the summer than it grows in the winter however, it retreats. But exactly how glaciers melt has not been understood in a comprehensive manner. What is known is that glacial ablation can be caused by any number of natural forces: wind, sun, rain, fauna, evaporation, sublimation and every other possible fashion one could imagine removing a chunk of ice from a even larger chunk of ice.

One of the most talked about forms of glacial ablation is glacial calving. Icebergs, for instance, are created when a chunk of glacier breaks off (or calves), usually falling into the body of water to which it drains. Calving often occurs from a process of erosion at the water line. Calving has gotten attention lately because of new evidence showing that for some glaciers, warmer ocean temperatures have been inarguably increasing the rate of glacial erosion underneath the water line. “Researchers found that, for some ice shelves, melting on its underbelly could account for as much as 90 per cent of the mass loss,” according to research published in Nature in September of last year. This aspect of glacial melt that was not previously well understood, but calving and ocean erosion are not the whole story to glacial ablation.

In 2008, Natalie Kehrwald, a Ph.D. student at Ohio State University, was attempting to date ice cores she drilled from a glacier in Tibet twenty thousand feet above sea level by searching for particular radioactive isotopes found all over the world from the mid-20th Century U.S. and Soviet Union atomic testing. She soon realized she couldn’t find the isotopes she was looking for. Confused, she used a different technique to date the top-most layer of the ice cores, and discovered that the newest ice in the samples dated from the 1940s. Kehrwald inadvertently proved that glaciers at those elevations in the Himalayas melt from top to bottom. Of course, it was the first time anyone had observed such a phenomenon, and it doesn’t mean top-down is the only way mountain glaciers melt.

At the Sandy Glacier on Mount Hood in Oregon, two climbers have discovered another particularly fascinating way glaciers melt. Brent McGregor and Eddy Cartaya have been exploring a system of glacial caves that extend more than 7,000 feet inside the glacier. Beautifully sculpted on the inside and ready-made for adventure, these glacier caves are significant because they exhibit glacial melt that is otherwise difficult to document. Scientist sometimes use satellites to record glacial melt, but those techniques would not perceive internal loss occurring within a glacier, as in the ice caves on Mount Hood. Andrew Fountain, a glaciologist at Portland State University, said he didn’t know of any effort to track how much the ice inside a glacier melts from year to year, before learning of the Sandy cave system, according to a recent Oregon Public Broadcasting article on the discovery.

Studying the many different ways the world’s glaciers can melt may help the scientific community better understand how to prevent them from disappearing.

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