Anthropogenic Sulfate and Asian Dust Signals in Snow from Tien Shan, Northwest China

Snow samples were collected from a 0.5 m snowpack at Glacier No. I and near Bogda Feng, eastern Tien Shan, northwest China. Samples that were melted in the field were analyzed for chloride, nitrate, sulfate, sodium, potassium, magnesium, calcium, and microparticles. Eight samples were returned frozen and were analyzed for the above ions plus ammonium, acetate, formate, methylsulfonate, and hydrogen peroxide. There was no significant difference in measured major ion concentrations between the melted and frozen samples. Measured cations in both sets of samples were two to three times greater than measured anions. Calcium and sodium are the dominant cations while sulfate is the dominant measured anion. High ion burdens are associated with dusty layers in the snowpack, indicating that dust from the vast arid regions of central Asia is the dominant source for major ions in Tien Shan snow. The significant increase in sulfate and decrease in the cation: anion ratio in Bogda Feng snow relative to Glacier No. I snow suggest that anthropogenic emissions from Urtimqi are an important source of sulfate to precipitation downwind from the city

Soluble species in aerosol and snow and their relationship at Glacier 1, Tien Shan, China

Simultaneous sampling of aerosol (n = 20) and snow (n = 114) was made at Glacier 1, Tien Shan, between May 19 and June 29, 1996. Similar temporal patterns of some major ion (calcium, magnesium, potassium, sodium, chloride, and sulfate) concentrations between snow and aerosol show that snow chemistry basically reflects changes in the chemistry of the atmosphere. This gives us confidence in the reconstruction of past atmospheric change using some snow data. There are no significant correlations between aerosol and snow samples for ammonium and nitrate. This suggests that post-depositional and/or post-collection processes may alter ammonium and nitrate concentrations in snow. The fact that the measured cations in aerosol and snow always exceed the measured anions suggests that the atmosphere is alkaline over Glacier 1, Tien Shan. In aerosol and snow samples, calcium is the dominant cationic species, with sulfate and presumed carbonate being the dominant anions. There is a very good inverse relationship (r = 0.96) between the equivalence ratio of calcium to sulfate and the ratio of ammonium to sulfate in aerosols, but this relationship does not hold for snow. This further suggests that post depositional and/or post collection processes exert important controls on ammonium concentrations in snow. Although melt-freeze cycles might increase the concentration of all crustal species through progressive dissolution of dust, these cycles seem most important for magnesium and carbonate

Estimating the characteristics of runoff inflow into Lake Gojal in ungauged, highly glacierized upper Hunza River Basin, Pakistan

Motivated by the potential flood outburst of Lake Gojal in the ungauged highly glacierized (27%) upper Hunza River Basin (HRB) in Pakistan that was dammed by a massive landslide on 4 January 2010, we attempt to analyze the characteristics of water inflow to the lake employing remote sensing data, two hydrological models, and sparsely observed data. One of the models (Model I) is a monthly degree-day model, while another (Model II) is the variable infiltration capacity (VIC) model. The mixture of glacier runoff output from Model I and runoff over unglacierized areas calculated by Model II has a similar seasonal variation pattern as that estimated from data recorded at a downstream station. This suggests that glacier runoff is the main source (87%) of runoff inflow into the lake. A sensitivity analysis suggests that the water inflow to the lake is highly sensitive to an increase in air temperature. Runoff in May is predicted to sharply increase by 15% to more than two-fold if the air temperature increases by 1 to 7, but it is predicted to increase only from 9% to 34% if the precipitation increases by 10% to 40%. The results suggested that the water inflow into Lake Gojal will not sharply rise even if there is heavy rain, and it needs to be in caution if the air temperature sharply increases. Analysis on long-term air temperature record indicates that the water inflow into the lake in May 2010 was probably less than average owing to the relatively low air temperature. Consequently, the flood outburst did not occur before the completion of the spillway on 29 May 2010. © 2013 China University of Geosciences and Springer-Verlag Berlin Heidelberg

Sub-debris melt rates on southern Inylchek Glacier, central Tian Shan

Melt rates of glacier surfaces are strongly influenced by the existence of a debris cover. Dependent on thickness and other physical parameters the debris layer can enhance or reduce ablation as compared to bare ice conditions. Supraglacial moraines appear very frequently on Central Asian glaciers, highly affecting water yield from these high mountain regions. In summer 2005, a network of 22 ablation stakes was drilled into locations with varying debris thicknesses on Southern Inylchek glacier in the central Tian Shan. Mean ablation rates varied from 2.8 to 6.7 cm/d, strongly correlated with moraine thickness. Parallel observation of air temperature allowed the application of a simple degree-day approach and the calculation of ablation rates. Efforts to improve calculations of melt rates by incorporating relative air humidity to account for latent heat fluxes failed. This proves that air temperature is already a very good melt indicator. Ice albedo measurements show that reflectivity might be controlled by the occurrence of evaporation or condensation, but this topic needs further investigation

Qinghai-Tibet Railway, China and the Solutions to Its Major Geotechnical Problems for Construction

The Qinghai-Tibet Railway (QTR) is the highest-elevation one for passenger trains in the world and the first railway to connect central China to Tibet. Construction of this railway starting in 2001 had to contend with major geotechnical challenges, such as permafrost, environmental protection and seismic hazards. Its completion in 2006 is a remarkable feat in the world’s railway construction history and crystallization of wisdom of human beings. In this paper, the planning and preparing history and the construction project of QTR are introduced. The major three thorny problems, permafrost, lack of oxygen and environmental frangibility for the construction and their solutions are presented, which are active methods of riprap roadbeds, heat pipe roadbed and bridges over land for permafrost, health care system for lack of oxygen and environmental protection measures for construction and operation. Seismic safety assessment was carried out for earthquake damage mitigation of the railway. The laboratory test, field test and observation, and it’s operation have shown that design, construction, and measures for earthquake hazards mitigation and environmental protection of the Qinghai-Tibet Railway are completely successful

Soluble Species in Aerosol and Snow and Their Relationship at Glacier 1, Tien Shan, China

Simultaneous sampling of aerosol (n = 20) and snow (n = 114) was made at Glacier 1, Tien Shan, between May 19 and June 29, 1996. Similar temporal patterns of some major ion (calcium, magnesium, potassium, sodium, chloride, and sulfate) concentrations between snow and aerosol show that snow chemistry basically reflects changes in the chemistry of the atmosphere. This gives us confidence in the reconstruction of past atmospheric change using some snow data. There are no significant correlations between aerosol and snow samples for ammonium and nitrate. This suggests that postdepositional and/or postcollection processes may alter ammonium and nitrate concentrations in snow. The fact that the measured cations in aerosol and snow always exceed the measured anions suggests that the atmosphere is alkaline over Glacier 1, Tien Shan. In aerosol and snow samples, calcium is the dominant cationic species, with sulfate and presumed carbonate being the dominant anions. There is a very good inverse relationship (r = 0.96) between the equivalence ratio of calcium to sulfate and the ratio of ammonium to sulfate in aerosols, but this relationship does not hold for snow. This further suggests that postdepositional and/or postcollection processes exert important controls on ammonium concentrations in snow. Although melt-freeze cycles might increase the concentration of all crustal species through progressive dissolution of dust, these cycles seem most important for magnesium and carbonate

COLLABORATIVE RESEARCH: A Glaciochemical Record of Natural and Anthropengic Environmental Change in the Northwestern North American Arctic

This is a collaborative proposal between the Universities of New Hampshire and Maine and the Geological Survey of Canada. This Office of International Science and Engineering is contributing to this award. The Principal Investigators will recover two ice cores the Eclipse Icefield (3100 meters) in the St. Elias Mountains, Yukon Territory, Canada in cooperation with the Geological Survey of Canada in 2002. The core will be analyzed for stable isotopes, major ions, trace elements, rare earth elements and persistent organic pollutants. The Eclipse record will provide, for the first time, detailed depositional histories of a wide variety of pollutants during the last 200 years in the remote northwest North American Arctic. Through the use of unique chemical tracers, the Principal Investigators will be able to identify source regions for these pollutants, changes in source regions with time, and the role of atmospheric circulation in controlling contaminant distributions in the northwest North American Arctic. The detailed multi-parameter record of natural and anthropogenic change will result in a greatly improved record of climate and environmental change for a region in which very few records currently exist

Variations in spruce (Picea sp.) distribution in the Chinese Loess Plateau and surrounding areas during the Holocene

&nbsp;&nbsp;&nbsp; Based on published pollen data from 44 sites in the Loess Plateau and surrounding areas, we recalculate values of Picea abundance digitized from the original diagrams and construct six isopoll maps to reconstruct the distribution of spruce forest at 2000 yr intervals during the Holocene. Spruce forest gradually expanded from about 10 ka BP ago and reached its peak distribution around 8 ka BP. It retained its maximum extent between 8 ka BP and 6 ka BP, broadly covering the subalpine area and stretching to the valleys of the western Loess Plateau with high densities and even reaching the edges of the adjacent desert regions. After 6 ka BP, spruce forest began to retreat to higher elevations. This trend was accelerated after 4 ka BP. After 2 ka BP, it disappeared completely from the Loess Plateau and most of its surrounding areas. Precipitation strongly dominated by the Asian summer monsoon was the primary controlling factor in the distribution of spruce before 2 ka BP. After about 2 ka BP, the increasing intensity of human activity became the primary factor in the disappearance of spruce in the Loess Plateau, resulting in an enormous impact on the present landscape.</h3

Collaborative Research: Asian Ice Core Array (AICA)--Reconstruction of Past Physical and Chemical Climate over Asia

Funding is provided to help the researchers build on success using ice cores for understanding past physical and chemical climate change from Antarctica, Arctic, North Pacific and Asia by analyzing and interpreting a new array of Asian ice cores. The researchers plan to use five existing ice cores and collect one new ice core to enhance the reconstruction of environmental conditions over Asia. The primary research questions for the Asian Ice Core Array (AICA) research include: (1) Asian climate variability - How do major Asian circulation features (i.e., Asian monsoon, Westerlies, polar air masses, Siberian and Tibetan Highs) vary on annual to longer scales? What factors (i.e., solar variability, volcanic activity, greenhouse gases) control changes in the major circulation features impacting Asia? What is the association between Asian climate and global circulation features? Can Asian climate be simulated and predicted from the state of past atmospheric circulation patterns (analog modeling)? How does the interaction between tropical and extra-tropical circulation impact climate over Asia? What are the regional climatic changes to be expected in near future based on trends? Are Asian climate change events related to climate change in other regions?(2) Environmental change over Asia - How have natural versus anthropogenic sources for chemical species notably sulfate, nitrate, and select heavy metals and trace and major elements varied in the atmosphere over central Asia? Are spatial and temporal variations in contaminants related to changes in contaminant source areas or production? Have changes in atmospheric circulation impacted distribution of chemical species in the atmosphere over central Asia?Scientifically, ice cores from Asian glaciers could provide a source of high-resolution records of seasonal to millennial climate dynamics and atmospheric chemistry. This is important because the Eurasian continent is the largest landmass in the World and exerts substantial influence on atmospheric and terrestrial systems and the 2.5 billion people living in the region. Changes in environment over this region could have dramatic impacts on humans and ecosystems. Unpredictable changes in water resources and desertification over this heavily populated region may have significant global consequences. The results from AICA could be of interest to climatologists, paleoclimatologists, atmospheric chemists, geochemists, climate modelers, solar-terrestrial physicists, and environmental statisticians. Educationally, the research project will support two PhD students as well as several undergraduate students for three years. This will help provide a rich research experience for the graduate and undergraduate students. Also, this project has strong ties to colleagues in China and Europe and offers intellectual and financial leveraging to aid in the success of the project