Posts by Yuanrong Zhou

Roundup: Black Carbon, Winds, and Supraglacial Lakes

Posted by on May 4, 2015 in All Posts, Featured Posts, Roundup | 0 comments

Roundup: Black Carbon, Winds, and Supraglacial Lakes

Spread the News:ShareLight-absorbing Particles in Peru “Glaciers in the tropical Andes have been rapidly losing mass since the 1970s. In addition to the documented increase in temperature, increases in light-absorbing particles deposited on glaciers could be contributing to the observed glacier loss. Here we report on measurements of lightabsorbing particles sampled from glaciers during three surveys in the Cordillera Blanca Mountains in Peru.” Read more here. Winds on Glaciers “We investigate properties of the turbulent flow and sensible heat fluxes in the atmospheric surface layer of the high elevation tropical Zongo glacier (Bolivia) from data collected in the dry season from July to August 2007, with an eddy-covariance system and a 6-m mast for wind speed and temperature profiles. Focus is on the predominant downslope wind regime.” Read more here. Supraglacial Lakes in Central Karakoram Himalaya “This paper discusses the formation and variations of supraglacial lakes on the Baltoro glacier system in the Central Karakoram Himalaya during the last four decades. We mapped supraglacial lakes on the Baltoro Glacier from 1978 to 2014 using Landsat MSS, TM, ETM+ and LCDM images. Most of the glacial lakes were formed or expanded during the late 1970s to 2008. After 2008, the total number and the area of glacial lakes were found to be lesser compared to previous years.” Read more here.   Spread the...

Read More

Photo Friday: Kyrgyz Glaciers

Posted by on Apr 24, 2015 in All Posts, Communities, Featured Posts, Images | 0 comments

Photo Friday: Kyrgyz Glaciers

Spread the News:ShareKyrgyzstan, located in Central Asia, is a country with enormous glaciers. About 30% of the total land area in Kyrgyzstan is covered by permanent snow and 4% is covered by glaciers. The total amount of glaciers in Kyrgyzstan is equivalent to 580 billion cubic meters of water, which can cover the whole country to a depth of 3 meters. The most famous glacier is the Enilchek Glacier in the Eastern Tien Shan mountain range. The Kyrgyz are semi-nomadic herders and their nomadic movements still take place seasonally. To learn about political controversies surrounding mining near glaciers in Kyrgyzstan, click here. Panorama of the Glacier Northern Inulchek with the glacial rivers and lakes. he hills Central Tian Shian is located in Central Asia. On the maximum points of this file there passes border of three countries - China, Kazakhstan and the Kirghizstan. On gorges of this hills powerful glaciers with the glacial rivers and lakes proceed. Here the most northern peaks with a mark above 7000ì. Peak of Khan Tengri 7010ì., and peak the Pobeda 7439ì are located. 5107239963_f42971bb19_b 5506051320_7e148753e1_b 6086490322_da8574ebfe_b 5508607661_81d3137d39_b 5107835696_b9b18beb3c_b 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...

Read More

New Discovery: Record of Glacial Cycles on Sea Floor

Posted by on Apr 14, 2015 in All Posts, Featured Posts, News, Science | 0 comments

New Discovery: Record of Glacial Cycles on Sea Floor

Spread the News:ShareThe history of the world’s hot and cold periods can be read on the ocean floor, according to a new study. The Earth has gone through cycles of glacial periods, when the great continental ice sheets advanced during colder periods, and interglacial periods – warmer climate cycles like like present day. These glacial-interglacial cycles are caused by the slow cycle of shifts in the Earth’s orbit, called Milankovitch cycles, which affect the amount of sunlight reaching the Earth. Now, scientists discovered that these ancient glacial-interglacial cycles are recorded on the sea floor through ocean ridges. A recent study by Crowley et al. in Oceanography demonstrated that new mapping of the sea floor from the Australian-Antarctic ridge showed statistically significant match with the Earth’s glacial cycles. “Step back and think about this: Small variations in the orbital parameters of the Earth—tilt and eccentricity and wobble—are recorded on the sea floor, it kind of blows my mind.” says Richard Katz, one of the researchers told Science Magazine. Each time the world passed between glacial and interglacial periods, global water distribution shifted. Specifically, when the Earth enters an ice age, the cold temperature freezes the sea water into glaciers, causing sea level to drop significantly. During the last glacial cycle, sea level dropped by 35 meters, which is more than twice the volume of the Greenland and West Antarctic ice sheets. As sea level drops, the pressure on the sea floor decreases accordingly. The ease in pressure allows magma beneath the seafloor to erupt and break the Earth’s surface, leading to divergence of the oceanic plates and forming the seafloor spreading center. This eruption thickens the crusts on teh sea floor and forms the abyssal hills – elevated landforms along the seaward margin parallel to mid-ocean ridges. So how did the researchers discover the record of glacial cycles on sea floor? The answer lies in the variations in crustal thickness at the seafloor spreading center. They examined the crustal thickness response to sea level change by computing the physical mechanisms beneath the sea floor, such as mantle flow, thermal structure, melting, and pathways of melt transport. The model they used, which predicts the time series of crustal thickness caused by sea level change, was used to simulate the dynamics of mid-ocean ridge. The numerical model results from this study contradict previous findings. Earlier research indicated an inverse relationship between variations in crustal thickness and spreading rate, which did not include the effects of sea level change. However, the new study reveals that melting or sensitivity to sea level variation does not simply decrease with increasing spreading rate. Instead, the crustal thickness response depends on changes in sea level and how long it took for melted magma to reach the surface. This newly discovered crustal response illustrates the link between glacial cycles and sea floor, contrary to findings from previous studies.   Spread the...

Read More

Roundup: Rock Avalanche, Melting Sound, Black Carbon

Posted by on Mar 23, 2015 in All Posts, Featured Posts, News, Roundup, Science | 0 comments

Roundup: Rock Avalanche, Melting Sound, Black Carbon

Spread the News:ShareLandslides on Glaciers “The chapter looks mainly at massive rock slope failures that generate high-speed, long- runout rock avalanches onto glaciers in high mountains, from subpolar through tropical latitudes. Drastic modifications of mountain landscapes and destructive impacts occur, and initiate other, longer-term hazards. Worst-case calamities are where mass flows continue into inhabited areas below the glaciers. Travel over glaciers can change landslide dynamics and amplify the speed and length of runout.” Read more about this chapter here.   Noise from Melting Glaciers “According to research accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union, the underwater noise levels are much louder than previously thought, which leads scientists to ask how the noise levels influence the behavior of harbor seals and whales in Alaska’s fjords.” Read more of this article.   Black Carbon in Tibetan Plateau “High temporal resolution measurements of black carbon (BC) and organic carbon (OC) covering the time period of 1956–2006 in an ice core over the southeastern Tibetan Plateau show a distinct seasonal dependence of BC and OC with higher respective concentrations but a lower OC / BC ratio in the non-monsoon season than during the summer monsoon. We use a global aerosol-climate model, in which BC emitted from different source regions can be explicitly tracked, to quantify BC source–receptor relationships between four Asian source regions and the southeastern Tibetan Plateau as a receptor.” Read the paper here.     Spread the...

Read More

Photo Friday: Alpine Photography by Fi Bunn

Posted by on Mar 20, 2015 in All Posts, Art/Culture, Experiences, Featured Posts, Images | 0 comments

Photo Friday: Alpine Photography by Fi Bunn

Spread the News:ShareFiona Bunn, a landscape photographer and alpinist, has been traveling to the Alps for over 25 years. Her alpine photography work has been frequently shared on social media, including The Alpine Club as well as Zermatt Tourism. Her work was recently included in an exhibition for a second time at The Brick Lane Gallery in the Shoreditch district of London’s East End. The exhibition featured the relationship between photographers and alpinists. Fi finds the worldwide alpine community to be supportive, with a desire to appreciate and express their interest in art. She  wrote “my aim is that my work highlights this vibrant, friendly, international community, who celebrate a shared interest for alpine exploration which literally crosses borders.” In addition, Fi is also concerned about climate change and glacial retreat. In her travels she has seen a large reduction in the size of glaciers firsthand. In an email she told GlacierHub,”I hope that my photos of these amazing mountains and glaciers perhaps help focus attention on how environmentally essential they are.” For more alpine photographs by Fi, please check out her website. dent blanche Castor 4228m, Pollux 4092m and Roccia Nera 4075m fi photos Matterhorn 4478m Monte Rosa, Hut & Lyskamm Allalinhorn 4027m Saas Fee Dufourspitze 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...

Read More