Posts by Yixing Zhu

Roundup: Cyanobacteria, Glacier Calving and Glacier Fluctuations

Posted by on May 25, 2015 in All Posts, Featured Posts, Images, News, Roundup, Science | 0 comments

Roundup: Cyanobacteria, Glacier Calving and Glacier Fluctuations

Spread the News:ShareArctic biocrust cyanobacterial communities “In the polar regions cyanobacteria are an important element of plant communities and represent the dominant group of primary producers. They commonly form thick highly diverse biological soil crusts that provide microhabitats for other organisms. Cyanobacteria are also producers of toxic secondary metabolites. The north-west coast of Spitsbergen, are able to synthesize toxins, especially microcystins and anatoxin-a. To the best of our knowledge, this is the first report on the presence of ANTX-a in the entire polar region. The occurrence of cyanotoxins can exert a long-term impact on organisms co-existing in biocrust communities and can have far-reaching consequences for the entire polar ecosystem.” See more about this article here   Dynamics of Glacier Calving “During summer 2013 we installed a network of nineteen GPS nodes at the ungrounded margin of Helheim Glacier in south-east Greenland together with three cameras to study iceberg calving mechanisms… The glacier calved by a process of buoyancy-force-induced crevassing in which the ice downglacier of flexion zones rotates upwards because it is out of buoyant equilibrium. Calving then occurs back to the flexion zone… “ See more about this article here.   Reconstruction of glacier fluctuations “It is presented the results of study of bottom sediments of the proglacial lakes enriched with meltwater of Peretolchin Glacier, Chersky Glacier and glaciers of the Kodar Ridge. Bottom sediments were investigated with time resolution in year-season, using X-ray fluorescence. We have defined three periods in significant increase of glacier flow/melting during the last 210 years. The first period (ca. 1800–1890), supply of suspended material by meltwater into Lake Ekhoy and Lake Preobrazhenskoe, was not intense until 1850 and 1875, respectively. However, the rate of meltwater supply into Lake Izumrudnoe was high during the Little Ice Age, and it is likely attributed to local moisture from Lake Baikal. The regional glacier water balances were most likely positive during the second period (ca. 1890–1940). The third period (ca. 1940–till present) was characterised by moderate melting rate of glaciers located on the Kodar and Baikalsky Ridges, in contrast to Peretolchin Glacier that demonstrated the highest rate of melting and changes in outlines during this period.” See more about this article here Spread the...

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Supercool water found near glaciers

Posted by on May 20, 2015 in All Posts, Featured Posts, Images, News, Science | 0 comments

Supercool water found near glaciers

Spread the News:ShareTemperatures in Spitbergen, Norway may be below freezing, but the water around the Glacier Front isn’t frozen, researchers Eugene Morozov from Shirshov Institute of Oceanology, Aleksey Marchenko from the University Center in Svalbard, and Yu. D. Fomin from Moscow Institute of Physics and Technology, found, This process of supercooling, also known as undercooling, happens when the temperature of a liquid or a gas drops below its freezing point without it becoming a solid. Experiments on Youtube show people taking liquid water out of their freezers, and pouring it on white plate under normal temperature. As the water hits the plate, it instantaneously turns into ice. There are two methods for making water supercool. The first method, like the one show in Youtube videos, can only be achieved when water is extremely pure. Impure water has ‘nucleation sites,’ where water molecules gather and gradually solidify during the freezing process. People can make supercool water with a simple refrigerator and a bottle of pure water. The other method relates to salinity and water pressure. Supercool water can occur under conditions of heat removal, different rates of heat and salt diffusion and rapid pressure decrease, chemists Valeria Molinero and Emily Moore in University of Utah found after much experimentation in 2011. With higher pressure, water will freeze at temperatures below 0 degree Celsius. In addition, higher salinity will also result in a lower freezing temperature. According to Figure 2, the freezing point will change depending on salinity and water pressure.     Previously, supercool water had only been created under laboratory conditions. However, the new findings from Eugene Morozov and his colleagues show that there is Glaciohydraulic supercooling water around the glacier that mixes and cools with high salinity and high pressure water. The bottom of the glacier is approximately 15 m from the sea surface. The melt water (fresh water) flows from the glacier at a temperature of 0 C. After mixing with surrounding seawater with a temperature of – 1.8 C, melt water cools to temperatures lower than -1.8 C while ascending to the surface. As it surfaces, its temperature is close to the freezing point of seawater(-1.8 C). That temperature is lower than the freezing temperature of freshwater and its internal energy does not reach the equilibrium state required for freezing. This freshwater from glaciers cools to temperatures lower than freezing without becoming ice.     The finding in Spitbergen is supported by research from Dr. Igor Dmitrenko, who works for Leibniz Institute of Marine Sciences at University of Kiel. He found that supercool water also exists in polynas, an area of open water surrounded by sea ice. However, this condition cannot be observed all the time since it cannot exist for an extended period. Supercooling water will transfer to the other states of water in a short time. It could play a crucial role in sea ice formation, researchers say. “While frazil ice [needle-shaped ice fragments in water] formation in the Arctic was carefully examined over the past several years for the St. Lawrence Island and the Storfjord polynyas […] the processes controlling the sea ice growth due to supercooled water and frazil ice formation over the Siberian Arctic shelf remain poorly understood, owing to the scarce instrumental records and extreme climatic conditions,” Dmitrenko wrote in his study.  “From these considerations, supercooling might play a critical role in the shelf salt budget and sea ice production” Check more information about glacier at Glacierhub. Spread the...

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Photo Friday: Visible Glacier Shrinking in Puncak Jaya

Posted by on May 8, 2015 in All Posts, Featured Posts, Images, Science | 0 comments

Photo Friday: Visible Glacier Shrinking in Puncak Jaya

Spread the News:ShareEven though mountain peaks near the equator have supported glaciers for thousands of years, they have retreated significantly in the last century because of climate change. Many tropical glaciers have lost more than half of their volume with the rapid development of global industry. Puncak Jaya, the earth’s highest island peak in Indonesia, holds the last glaciers in the tropical Pacific. Back in 1989, five ice masses sat on the slopes of Puncak Jaya. But by 2009, two of the glaciers, Meren and Southwall, were gone. The other three, Carstenz, East Northwall Firn, and West North Wall Firn, have retreated dramatically since the 1970’s, according to satellite imagery analyzed by Joni L. Kincaid and Andrew G. Klein, from the department of Geography in Texas A&M University. The Meren Glacier melted away sometime between 1994 and 2000. Pictures below, provided by NASA and U.S. Government show, the dynamic shrinking glacier in Puncak Jaya. sight 2009 1989 1972 1936 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.  Spread the...

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Climate Change Adaptation is Key to Water Security

Posted by on Apr 29, 2015 in Adaptation, All Posts, Featured Posts | 1 comment

Climate Change Adaptation is Key to Water Security

Spread the News:ShareA significant research gap may be hindering community efforts to withstand climate-induced glacier melt, according to a new review from researcher Graham McDowell and his colleagues at McGill University. Understanding how to help communities adapt to the effects of glacier melt, which threatens water sources for communities worldwide, will require deeper assessments of existing projects, the review found. A research agenda should focus on assessing different adaptation measures to better inform policy and community projects in the future. Glaciers are key water sources in mountain areas, especially in South America and South Asia. More than 72 million people live in mountain regions, and large proportions of these populations reside in glaciated regions. Without glaciers, the livelihoods and health of communities worldwide will be threatened, but the issue is not well understood. Only 36 studies of adaptation projects have been published. In total, studies document 74 adaptations, mainly in Peru, India and Nepal, though the lack of research in this area suggests the number of existing adaptation plans may be greater than researchers have studied. Almost 50 percent of documented adaptation plans are driven by a need to cope with the repercussions of climate change. Adaptation plans differ depending on how communities living near glaciers make their livelihoods, whether they are in ski towns in the European Alps or subsistence agrarian communities in the Himalayas and Andes. McDowell found that most of the work on adaptation in glaciated regions comes from academic institutions, while NGOs and governments contribute much less. 50% of the projects in the papers which McDowell et al. reviewed concentrated in agricultural sector, followed by hazard management (31%), tourism (26%), water management (24%) and public health security (19%). McDowell’s assessment suggests that adaptations to climatic changes are frequently embedded within responses to other socio-economic, political, and environmental challenges. To address these challenges, autonomous adaptation without government help at local scales may be especially important in often-remote glaciated mountain regions, where 58 % of adaptation initiatives were at an individual, household, or community scale, and 46 % were categorized as being autonomous, the review found. Communities in need South America, which holds more than 99% of the world’s tropical glaciers, is particularly vulnerable to global warming. As climate change converges with human activities in glacier-filled mountains, the degradation of high Andean ecosystems is accelerating. These glaciers, which provide drinking water and sustain rivers, are crucial to water supply in South America and are used for agriculture, hydroelectricity and industry such as agro-exports and mining. At the same time, there are growing concerns that the rainy season will bring a higher risk of flooding, even if climate change leads to seasonal drought in the region. Facing abnormal rainfall, local farmers have to adapt to avoid economic loss. Unavoidable glacier melt will severely reduce water supply in a continent that is already water-poor. In Peru, 8.9 million people live in rural areas and 3.3 million currently don’t have access to safe portable water. Around 3 million people, most of them children, die each year related to disease linked to consumption of contaminated water. In order to provide more safe potable water, people are now trying to build large public facilities, such as reservoirs to store drinking water. However, microorganisms such as E. coli, Salmonella and Campylobacter are a concern as studies show increased temperatures favor conditions under which these microorganisms thrive. A research agenda that addresses projects that can help communities adapt to the cascading effects of climate change is becoming increasingly urgent as the lives of millions come under threat. For more information about adaptation in glacier areas, look here. Spread the...

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Photo Friday: Tulips in the Wild

Posted by on Apr 3, 2015 in All Posts, Experiences, Featured Posts, Images | 0 comments

Photo Friday: Tulips in the Wild

Spread the News:ShareFew people have had seen tulips grow in their original habitat even though they are a familiar presence in gardens and florist shops. Here is a great opportunity to discover the tulips that are native to some of the most remote places on earth. Mountains at high elevations, especially the area centering on the glacier-filled Pamirs and Tien Shan Mountains of Central Asia, are the habitats of wild tulips. The bulbs of these flowers store energy which allows them to grow quickly in the short spring and summer seasons at high elevations. Many wild tulips grow in rock crevices on these mountains. Some wild tulips may languish in garden soil in a more temperate climate – they can only survive in their natural habitats. “Ironic as it may seem, many of these rugged beauties are easily killed with kindness.” Eric Breed, a freelance bulb photographer and a member of Tulips in the Wild , states on his website. Eric and his friends travel to the lands where tulips grow wild and capture the most beautiful moments of these flowers. For more wild tulips photographs, please check out Tulips in the Wild.  Many thanks to Sally Ferguson, Colorblends and the Amsterdam Tulip Museum for their help. wild tulips T. bakeri is endemic to the Omalos Plain (1,000m/3,300ft) in the Lefka Ori (White Mountains) of western Crete. wild tulips Tulips, especially those with needlelike petals, were greatly prized by sultans such as Ahmed III, who reigned from 1703 to 1730. wild tulips As soon as the snow melts, the fragrant flowers begin to emerge. wild tulips tulips in the wild wild tulips This grape farmer has stepped on a plant in bloom as though it were just another weed wild tulips At higher elevations—up to 5,000m/16,400ft—plants can sometimes be found blooming into August. 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.  Spread the...

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