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Full-Text Articles in Physical Sciences and Mathematics
A Case Study Using 2019 Pre-Monsoon Snow And Stream Chemistry In The Khumbu Region, Nepal, Heather M. Clifford, Mariusz Potocki, Inka Koch, Tenzing Sherpa, Mike Handley, Elena Korotkikh, Douglas Introne, Susan Kaspari, Kimberley Miner, Tom Matthews, Baker Perry, Heather Guy, Ananta Gajurel, Praveen Kumar Singh, Sandra Elvin, Aurora C. Elmore, Alex Tait, Paul A. Mayewski
A Case Study Using 2019 Pre-Monsoon Snow And Stream Chemistry In The Khumbu Region, Nepal, Heather M. Clifford, Mariusz Potocki, Inka Koch, Tenzing Sherpa, Mike Handley, Elena Korotkikh, Douglas Introne, Susan Kaspari, Kimberley Miner, Tom Matthews, Baker Perry, Heather Guy, Ananta Gajurel, Praveen Kumar Singh, Sandra Elvin, Aurora C. Elmore, Alex Tait, Paul A. Mayewski
Geological Sciences Faculty Scholarship
This case study provides a framework for future monitoring and evidence for human source pollution in the Khumbu region, Nepal. We analyzed the chemical composition (major ions, major/trace elements, black carbon, and stable water isotopes) of pre-monsoon stream water (4300–5250 m) and snow (5200–6665 m) samples collected from Mt. Everest, Mt. Lobuche, and the Imja Valley during the 2019 pre-monsoon season, in addition to a shallow ice core recovered from the Khumbu Glacier (5300 m). In agreement with previous work, pre-monsoon aerosol deposition is dominated by dust originating from western sources and less frequently by transport from southerly air mass …
Spectral Signatures Of Submicron Scale Light-Absorbing Impurities In Snow And Ice Using Hyperspectral Microscopy, Farra Dal Anna, Susan Kaspari, James Beach, Thomas D. Bucheli, Michael Schaepman, Margit Schwikowski
Spectral Signatures Of Submicron Scale Light-Absorbing Impurities In Snow And Ice Using Hyperspectral Microscopy, Farra Dal Anna, Susan Kaspari, James Beach, Thomas D. Bucheli, Michael Schaepman, Margit Schwikowski
Geological Sciences Faculty Scholarship
Light-absorbing impurities (LAI) can darken snow and ice surfaces, reduce snow/ice albedo and accelerate melt. Efforts to allocate the relative contribution of different LAI to snow/ice albedo reductions have been limited by uncertainties in the optical properties of LAI. We developed a new method to measure LAI spectral reflectance at the submicron scale by modifying a Hyperspectral Imaging Microscope Spectrometer (HIMS). We present the instrument’s internal calibration, and the overall small influence of a particle’s orientation on its measured reflectance spectrum. We validated this new method through the comparison with a field spectroradiometer by measuring different standard materials. Measurements with …
Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen
Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen
All Faculty Scholarship for the College of the Sciences
High-resolution δ18O records from a Geladaindong mountain ice core spanning the period 1477-1982 were used to investigate past temperature variations in the Yangtze River source region of the central Tibetan Plateau (TP). Annual ice-core δ18O records were positively correlated with temperature data from nearby meteorological stations, suggesting that the δ18O record represented the air temperature in the region. A generally increasing temperature trend over the past 500 years was identified, with amplified warming during the 20th century. A colder stage, spanning before the 1850s, was found to represent the Little Ice Age with colder …
Optimized Method For Black Carbon Analysis In Ice And Snow Using The Single Particle Soot Photometer, I. A. Wendl, James A. Menking, R. Färber, M. Gysel, Susan D. Kaspari, M. J. G. Laborde, M. Schwikowski
Optimized Method For Black Carbon Analysis In Ice And Snow Using The Single Particle Soot Photometer, I. A. Wendl, James A. Menking, R. Färber, M. Gysel, Susan D. Kaspari, M. J. G. Laborde, M. Schwikowski
All Faculty Scholarship for the College of the Sciences
In this study we attempt to optimize the method for measuring black carbon (BC) in snow and ice using a Single Particle Soot Photometer (SP2). Beside the previously applied ultrasonic (CETAC) and Collison-type nebulizers we introduce a jet (Apex Q) nebulizer to aerosolize the aqueous sample for SP2 analysis. Both CETAC and Apex Q require small sample volumes (a few milliliters) which makes them suitable for ice core analysis. The Apex Q shows the least size-dependent nebulizing efficiency in the BC particle diameter range of 100–1000 nm. The CETAC has the advantage that air and liquid flows can be monitored …
Seasonal And Elevational Variations Of Black Carbon And Dust In Snow And Ice In The Solu-Khumbu, Nepal And Estimated Radiative Forcings, Susan Kaspari, T. H. Painter, M. Gysel, S. M. Skiles, M. Schwikowski
Seasonal And Elevational Variations Of Black Carbon And Dust In Snow And Ice In The Solu-Khumbu, Nepal And Estimated Radiative Forcings, Susan Kaspari, T. H. Painter, M. Gysel, S. M. Skiles, M. Schwikowski
All Faculty Scholarship for the College of the Sciences
Black carbon (BC) and dust deposited on snow and glacier surfaces can reduce the surface albedo, accelerate snow and ice melt, and trigger albedo feedback. Assessing BC and dust concentrations in snow and ice in the Himalaya is of interest because this region borders large BC and dust sources, and seasonal snow and glacier ice in this region are an important source of water resources. Snow and ice samples were collected from crevasse profiles and snow pits at elevations between 5400 and 6400 m a.s.l. from Mera glacier located in the Solu-Khumbu region of Nepal during spring and fall 2009, …
Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar
Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar
Undergraduate Honors Theses
The eastern portion of Washington State's Cascade Range is a place not previously examined for rock glaciers, due to proximity to the Pacific Ocean and its associated marine-influenced climate. The objectives of this study were to determine spatial, activity, and genesis patterns, and paleoclimatic implications of Eastern Cascade rock glaciers. Using Google Earth, I found 103 rock glaciers in the study area. Rock glaciers are more common further east of the Cascade crest and more north in latitude, with the largest concentrations occurring east of Lake Chelan (22) and in the Pasayten Wilderness (28) in the North Cascades. None were …
Predictability Of Biomass Burning In Response To Climate Changes, A.-L. Daniau, Megan Walsh
Predictability Of Biomass Burning In Response To Climate Changes, A.-L. Daniau, Megan Walsh
All Faculty Scholarship for the College of the Sciences
Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo- fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from …
Historical Changes In Mid-Water Stands Of Common Reed In The Winnebago Pool Lakes, Wisconsin, Anthony O. Gabriel, Leo R. Bodensteiner
Historical Changes In Mid-Water Stands Of Common Reed In The Winnebago Pool Lakes, Wisconsin, Anthony O. Gabriel, Leo R. Bodensteiner
All Faculty Scholarship for the College of the Sciences
Despite the tolerance of common reed grass to environmental extremes, mid-water stands in the Winnebago pool lakes of central Wisconsin appear to be diminishing. Formerly occupying shoreline locations, water level manipulations subsequent to dam construction beginning in the 1850's have isolated reed stands off shore. These stands have persisted but casual observations indicate that stand size has been declining. To address this perception we obtained an approximately decadal series of aerial photographs dating back to 1937 for four stands in Lake Poygan. Annual records were available for 1986–94. Using image analysis software, we determined shape and size metrics. Changes in …