Spatio-temporal variability and energy-balance implications of surface ponds on Himalayan debris-covered glaciers

Surface ponds play a key role in transferring atmospheric energy to the ice for debris-covered glaciers, but as the spatial and temporal distribution of ponds is not well documented, their effect on glacier ablation is unknown. This thesis uses remote sensing and field methods to assess the distribution of supraglacial ponds in the Langtang Valley of Nepal, then develops and applies numerical models of pond surface energy balance to determine energy receipts at the pond, glacier, and basin scales. 172 Landsat TM/ETM+ scenes are analysed to identify thawed supraglacial ponds for the debris-covered tongues of five glaciers for the period 1999-2013. There is high variability in the incidence of ponding between glaciers, and ponds are most frequent in zones of low surface gradient and velocity. The ponds show a pronounced seasonality, appearing rapidly in the pre-monsoon as snow melts, reaching a peak area in the monsoon of about 2% of the debris-covered area, then declining in the post-monsoon as ponds drain or freeze. The satellite observations are supplemented by diverse field observations on Lirung Glacier in the Langtang Valley made in 2013 and 2014, confirming that overall pond area is markedly higher in the pre-monsoon than post-monsoon. Four ponds are observed in detail showing pond drainage, stability, and growth. The thesis then advances efforts to develop a model of mass and energy balance for supraglacial ponds, using field data from a small pond on Lirung Glacier. Sensitivity testing is performed for several key parameters and alternative melt algorithms. The pond acts as a significant recipient of energy, and participates in the glacier’s local hydrologic system during the monsoon. The majority of absorbed energy leaves the pond via englacial conduits, delivering sufficient energy to melt 2612 m3 of ice (~5.3 m ablation for the pond area). Energy receipts for all Lirung Glacier ponds for 2014 are then determined, using the full model and simpler approaches based on data availability. The partition of absorbed energy between pond-proximal and englacial melt is inconsistent between ponds, and the shortwave energy balance alone is not adequate to represent pond energy absorption. The model results suggest that ponds absorbed sufficient energy to account for ~10% of Lirung Glacier’s ablation in 2014.Finally, a simplified pond surface energy-balance model is applied to assess pond energy absorption for the entire Langtang catchment, using local meteorological data for 2013 and mean monthly pond distributions from the Landsat observations. Supraglacial ponds are found to absorb sufficient atmospheric energy to account for 5-16% (mean ~12%) of the debris-covered area’s volume loss in 2013 (equivalent to 0.11 m thinning for this area). Less absorption occurs in the pre-monsoon and post-monsoon than in the monsoon due to decreased latent heat exchange. Altitude is an additional control, but seasonal surface energy balance remains positive at the ELA of 5400 m. This research suggests that due to the efficiency of supraglacial ponds as vectors of atmospheric energy to the glaciers’ interior, they may account for a considerable portion of the debris-covered area’s ablation (~10%) in spite of their low aerial coverage (1-2%), and ponds must be accounted for in studies of debris-covered glacier ablation and evolution

Design And Implementation of An Automatic Word Generator For Word Matching Interactives

An Automatic Word Match Generator is a software tool that can be used to generate word-matching interactives automatically. The purpose of a word-matching interactive is to provide students with the mechanism to learn new vocabulary and improve their reading comprehension skills. This thesis will present the design and implementation of an Automatic Word Match Generator, as well as the research and algorithms used in the program

Impact of Shared Discovery on Consortium Borrowing: Analyzing TRLN Discovery and TRLN Direct

In 2019, the Triangle Research Libraries Network (TRLN) launched a new shared index and discovery platform called TRLN Discovery that allowed users to seamlessly switch from local holdings to consortium holdings using a search facet. This new catalog was released as localized versions for member institutions. TRLN Discovery followed the development of consortium resource sharing system called TRLN Direct. To evaluate these resource sharing projects, this paper assesses the impact of shared discovery on consortium resource sharing at UNC Chapel Hill. Analysis of interlibrary borrowing and Document Delivery request data does not show an increase in request volume or number of patrons attributable to TRLN Discovery. Both new and returning users, however, are more likely to use consortium searches to place requests with the new catalog. These findings indicate that while users have an interest in using consortium resource discovery platforms, these user experience changes do not directly create demand.Master of Science in Library Scienc

S21RS SGR No. 19 (Indian mounds public statement)

A Resolution To urge and request Louisiana State University to make public statements discouraging people from going onto the LSU Indian Mound

S21RS SGR No. 19 (Discouraging going on the Indian Mounds)

A Resolution To Urge and Request Louisiana State University to make public statements discouraging people from going onto the LSU Indian Mound

Surface and subsurface hydrology of debris-covered Khumbu Glacier, Nepal, revealed by dye tracing

While the supraglacial hydrology of debris-covered glaciers is relatively well studied, almost nothing is known about how water is transported beneath the glacier surface. Here, we report the results of sixteen fluorescent dye tracing experiments conducted in April–May 2018 over the lowermost 7 km of the high-elevation, debris-covered Khumbu Glacier, Nepal, to characterise the glacier's surface and subsurface drainage system. Dye breakthroughs indicated a likely highly sinuous and channelised subsurface hydrological system draining water from the upper part of the ablation area. This flowpath was distinct from the linked chain of supraglacial ponds present along much of the glacier's lower ablation area, through which water flow was extremely slow (∼0.003 m s−1), likely reflecting the study's timing during the pre-monsoon period. Subsurface drainage pathways emerged at the glacier surface close to the terminus, and flowed into small near-surface englacial reservoirs that typically delayed meltwater transit by several hours. We observed rapid pathway changes resulting from surface collapse, indicating a further distinctive aspect of the drainage of debris-covered glaciers. We conclude that the surface and subsurface drainage of Khumbu Glacier is both distinctive and dynamic, and argue that further investigation is needed to refine the characterisation and test its regional applicability to better understand future Himalayan debris-covered glacier meltwater delivery to downstream areas

Internal structure of a Himalayan debris-covered glacier revealed by borehole optical televiewing

Characterising the structures within glaciers can give unique insight into ice motion processes. On debris-covered glaciers, traditional structural glaciological mapping is challenging because the lower glacier is hidden by the supraglacial debris layer. Here, we use high-resolution optical televiewer (OPTV) image logs from four boreholes drilled into Khumbu Glacier, Nepal, to overcome this limitation and investigate englacial structural features within a Himalayan debris-covered glacier. The OPTV logs show structural features that are up to an order of magnitude thinner than those observed at the glacier surface and reveal five structural units: (I) primary stratification of ice; (II) debris-rich planes that conform with the primary stratification; (III) water-healed crevasse traces; (IV) healed crevasse traces; and (V) steeply dipping planes of basally derived fine sediment near the glacier terminus. The OPTV logs also reveal that the primary stratification both decreases in dip with depth (by up to 56° over 20 m) and rotates with depth (by up to 100° over 20 m) towards parallelism with the proximal lateral moraine. This transformation and the presence of relict layers of basally derived sediment raised into an englacial position - possibly involving thrusting - near the glacier's now stagnant terminus reveal a previously more dynamic glacier regime

Instruments and Methods:hot-water borehole drilling at a high-elevation debris-covered glacier

While hot-water drilling is a well-established technique used to access the subsurface of ice masses, drilling into high-elevation (≳ 4000 m a.s.l.) debris-covered glaciers faces specific challenges. First, restricted transport capacity limits individual equipment items to a volume and mass that can be slung by small helicopters. Second, low atmospheric oxygen and pressure reduces the effectiveness of combustion, limiting a system's ability to pump and heat water. Third, thick supraglacial debris, which is both highly uneven and unstable, inhibits direct access to the ice surface, hinders the manoeuvring of equipment and limits secure sites for equipment placement. Fourth, englacial debris can slow the drilling rate such that continued drilling becomes impracticable and/or boreholes deviate substantially from vertical. Because of these challenges, field-based englacial and subglacial data required to calibrate numerical models of high-elevation debris-covered glaciers are scarce or absent. Here, we summarise our experiences of hot-water drilling over two field seasons (2017–2018) at the debris-covered Khumbu Glacier, Nepal, where we melted 27 boreholes up to 192 m length, at elevations between 4900 and 5200 m a.s.l. We describe the drilling equipment and operation, evaluate the effectiveness of our approach and suggest equipment and methodological adaptations for future use

Experiential-based learning in engineering project management within a global economy

Introduction Over the past century, great technological advances have enabled high-speed communication and transportation across the globe. This technology trend combined with the needs of continuous expansion of market place has motivated major corporations not to restrict their business activities to within a single principality. Engineering design activities can take place across the globe, while projects themselves tend heavily towards larger and international scope, affecting greater numbers of diverse populations within numerous principalities. The social, cultural, political, and economical differences have inevitably raised tremendous challenges for coordinating widely spread, yet inter-connected collaboration project activities among the various stakeholders. This establishes the need for effective project management to ensure that the stakeholders, all with diverse backgrounds, cooperate to effectively progress to the project’s completion for the corporate sector, governmental organizations, and non-profit groups. Though extensive project management literature exists, little has been done on addressing the challenges faced by new managers in a global economy. In addition, in the current engineering curriculum, scant attention has ever been put on teaching such knowledge. This has left those inexperienced young engineers with frustration when beginning a prominent project management position. It is therefore crucial to develop innovative ways of acquiring such knowledge, and this thesis will address some of the major project management challenges in a global economy and share case studies on experiential-based learning. Thesis Statement This thesis seeks to discuss international engineering project management as a broad practice, and will include the author’s learnings in the specific area

Environmental impact assessment of: Sunset Fish Passage and Energy Project

The Snohomish County Public Utility District (PUD) No. 1 filled for a preliminary permit with the United States of America Federal Energy Regulatory Commission (FERC) to study the feasibility of a hydroelectric project on the South Fork of the Skykomish River on September 28th, 2011. This small scale hydroelectric project is referred to as the Sunset Fish Passage and Energy Project. By 2015 the FERC had approved the preliminary permit, as well as granted a two-year extension to the Snohomish PUD to continue investigations. In addition to the proposed hydro project, this document suggests an expansion of a pre-existing wind energy facility, called Wild Horse Wind and Solar Facility, as an alternative to subsidize the energy output from the hydro facility. The following Environmental Impact Assessment (EIA) discusses the probable environmental impacts that would result from the hydroelectric project, alternative wind energy project, and no action alternative