COUPLING GLACIO-HYDROLOGICAL RESPONSE TO CLIMATE VARIABILITY IN MT EVEREST REGION IN CENTRAL HIMALAYA

Mt. Everest region in the central Himalaya is one of the most heavily glacierized parts of the Himalaya that is characterized by large debris-covered glaciers and many glacial lakes. The glaciers and ice are important sources of fresh water and play vital role in modulating the climate and the hydrological process. Previous studies from different parts of the Himalaya and around the world have revealed climate change at regional and global-scale and in general, shrinking of glaciers and ice caps. Climate change is thus, expected to impact in many ways to Cryosphere, hydrological process, and human livelihood. Temperature is often suggested to be increasing and considered as the main driver of change, however, in the higher elevations where the glaciers exist, climatic data are rarely available and limiting the climate related interpretation. This study is therefore conducted with the aim of linking variation of glaciers, glacial lakes, and river flow to local climatic trends in the higher elevations of Mt. Everest region. The study uses a comprehensive multi-temporal data from different sources: satellite observations, ground hydro-meteorological stations, and regular gridded and reanalysis climate data from the regional and global products (1960s to 2013). First, using the weather data from ground stations, gridded, and reanalysis products, the climatic trends and climate variability are evaluated. From 1979 to 2013, temperature has increased by 0.052 \ub0C a-1, while the precipitation has shown an increasing tendency in 1960s to early 1990s and significantly decreasing afterward. During 1994\u20132013 period, at an elevation of ~ 5000 m, minimum temperature (0.072 \ub1 0.011 \ub0C a-1) has increased more than maximum temperature (0.009 \ub1 0.012 \ub0C a-1), with an average temperature increase of 0.044 \ub1 0.008 \ub0C a-1 in the last two decades. The increases in the temperature are observed during the pre- and post-monsoon months, favouring melting ice close to the glacier terminus. At the same elevation, precipitation has significantly decreased (-9.3 \ub1 1.8 mm a-1) for all months, corresponding to a loss of 47 % during the monsoon. Second, the glacier changes are studied within the Sagarmatha (Mt. Everest) National Park (SNP; glacier area: ~ 400 km2) between 1962 and 2011, using multi-temporal optical satellite imagery, assisted by topographic maps. During the period, glaciers have experienced a surface area loss of 13.0 \ub1 3.1 %, an average terminus retreat of 403 \ub1 9 m, a Snow-Line Altitude (SLA) upward shifting of 182 \ub1 22 m, and an increasing of debris- covered area by 17.6 \ub1 3.1 %. An accelerated rate of glacier shrinkage is observed after the 1990s, which is caused not only due to increased temperature, but also as a result of a significant decreasing precipitation over the last decades. Moreover, selected glaciers have indicated a significant decreasing glacier flow velocities from the 1990s to recent year and a significant loss of glacier thickness (0.73 \ub1 0.63 m a-1) in the last decade. Third, a complete mapping and characterization of a total of 624 glacial lakes with surface area of 7.43 km2 (\ub118 %) are conducted in the SNP, with particular focus on conditions related to the formation of lakes using 2008 satellite imagery. Further, evolutions of glacial lakes are examined using the satellite imagery and topographic maps between 1963 and 2013. Three types of glacial lakes (supra, pro, and unconnected) present in the SNP have their distinctive potential to explain the glaciological and climatic conditions. Results show that the slope of the glacier where lakes are located influence the supraglacial lake formation. Furthermore, the slope to glacier upstream favours the formation of the supraglacial lakes, as a boundary condition. The formation of proglacial lakes is related to the growing and coalescing of the supraglacial lakes. The unconnected lakes are evaluated as a useful indicator of precipitation trend. During the study period (1960s\u20132011), both number and surface area of supraglacial lakes has continuously increased (number +109.7 %; area +13.3 %) with an accelerated rate in the last decade due to increase in the glacier melting. Proglacial lakes are more or less constant in both numbers and size, except Imja Lake that have exceptionally increased, while the surface area of unconnected lakes has increased from 1960s\u20131990s (+4.3 %) and decreased from early 1990s afterward (-10.9 %). The thesis has shown that the accelerated rate of glacier shrinkage and the decreasing of the unconnected lakes in the last decades are associated to decreasing precipitation. Supraglacial lakes behaviour confirms the acceleration of the negative mass balance of glaciers due to the reduced ice velocities caused by decreased precipitation. Finally, the hydrological dynamics of the Dudh Koshi river examined by stochastic frequency analysis, physically-based hydrological models, and multilinear regression using river discharge data and climate data. The analysis suggests that the Dudh Koshi river discharge is mainly dependent on precipitation from 1960s to 2000s, however a non-stationarity in the river discharge is observed since the early 2000s, indicating increased discharge, not justifiable by the observed weakening monsoon. The study concludes by underlining that an accelerated glacier melting as observed through the glacier change analysis affects an increasing of the discharge

Energy, forest, and indoor air pollution models for Sagarmatha National Park and Buffer Zone, Nepal

This paper presents the results of management-oriented research on energy, forest, and human health issues in a remote mountain area, the Sagarmatha National Park and Buffer Zone (SNPBZ), Nepal. The research was based on a broader, integrated participatory framework ultimately intended for use in adaptive management. The present study focused on the application of a participatory modeling framework to address problems related to energy demand and consumption, forest condition, and indoor air pollution, which were defined by the stakeholders as important issues to be addressed. The models were developed using a generalizing design that allows for user-friendly adaptation to other contexts (free download at http://hkkhpartnership.org). Moreover, we simulated management scenarios in collaboration with all modeling actors with the aim of building consensus on the understanding of the system as well as supporting decision-makers' capacity not only to respond to changes, but also to anticipate them. Importantly, the system dynamics assessment found that the SNPBZ forests are affected by an increasing demand for fuelwood (occurring due to tourism growth), as one of the main sources of energy. Selected forests show an average reduction of 38 in forest biomass from 1992 to 2008. This shows that the business-as-usual scenario is unlikely to result in the preservation of the current forest status; in fact, such preservation would require 75 of fuelwood to be replaced with alternative energy sources. At the same time, a 75 reduction of fuelwood use (and an 80 reduction of dung use) would reduce indoor carbon monoxide (CO) concentrations to the standard limits for CO exposure set by the World Health Organization

High altitude smokeless metal stove: A research, development and implementation project through the Kathmandu University

This paper aims to highlight the importance and need of a Smokeless Metal Stove (SMS) for high altitude rural communities, in order to improve their health condition through better indoor air conditions, and to help in active ways to slow down the fast increasing, wide spread deforestation. It brings close through facts and pictures the living conditions and way of life of people who suffer under open indoor fire places, as well as the improved living conditions and benefits people themselves have identified through the use of a smokeless metal stove in their home. Experiences from actual “Jumla Design” stove installations in the villages in Humla, as well as the latest KU laboratory data and results of the new designed secondary combustion stove prototypes are discussed and presented through pictures, data and graphs

Identification and evaluation of the losses occurring in a solar PV system under real field conditions for rural electrification in Humla

Nepal, which is situated along the solar belt of 30° northern latitude, is blessed with an average of 300 days of sunshine a year. Over the last decade, private companies and local NGOs/INGOs have been increasingly providing electricity services through government subsidised Solar Photovoltaic (PV) Systems to the local communities for basic indoor lighting in rural areas. In many cases, the users consider PV technology to be inappropriate when the performance of their solar PV system is less than what they expected or were initially promised. The understanding of the real field conditions in a set environment, as well as the losses occurring due to PV cell temperatures, PV module mismatches, wrong battery bank usage etc. are lacking, not discussed or considered in the design of a PV system prior to its installation. In order to identify and understand the losses which may occur in installed solar PV systems, and thus understand their limited performance in greater detail, Kathmandu University (KU) and Rural Integrated Development Service (RIDS)–Nepal, with the support of the ISIS Foundation, have started monitoring several solar PV systems' performance on a continual basis within their installed geographical, meteorological and users' context in one of the remotest and poorest communities in Humla, Nepal. This paper aims to identify and present the main losses in a solar PV system. In particular, losses occurred due to non-standard temperature conditions (STC), non-ideal PV module angle position, increased PV cell temperature, PV module mismatch, and battery bank and wire losses, are discussed and presented with data, graphs and pictures

Studies of air molecules at high sensitivities with the reflection interferometer under various vacuums

In this work, we report the studies of air molecules by recently developed reflection interferometer. The interferometer is highly sensitive so that the interference signal allows the monitoring of the index of the refraction of air under various vacuum, revealing the molecular behavior of air molecules by Kramers–Kronig relations. The interferometer is composed of a channel of a thickness of 13 µm and a width of 5mm. We have used a green laser of wavelength 532 nm and a red laser of wavelength 633 nm with the incident beam at an oblique angle. The vacuum ranged from 0 to -9.2 PSI. Our results reveal the molecular details of the dynamic nature of air molecules

In-stream habitat availability for river dolphins in response to flow: Use of ecological integrity to manage river flows

Population decline and extinction risk of river dolphins are primarily associated with flow alteration. Previous studies predominantly highlighted maintenance of adequate flow for low water seasons when habitats contract and the risk of local extinction escalates. Although river dolphins are sensitive to reduction in river flow, no studies quantify the relationships between flow and ecology of river dolphins to mitigate the potential adverse impacts of flow alteration. We quantify the relationships between flow and the ecology of river cetaceans concerning Ganges River dolphins (GRD; Platanista gangetica gangetica) usable area availability (AWS) for the low water season at wider flows (50-575 m3/s) at finer spatial and temporal scales. This study reveals that distribution of area usable to GRD is highly regulated by the adequate flow and river attributes (velocity and depth) interactions that likely offer energetically efficient modes of locomotion to GRD, suggesting the hydro-physical environment as a major determinant of river dolphin distribution and abundance. Flow and AWS relationships indicate that the flow during the dry season negatively contributed to AWS, whereas that of pre-monsoon maximized the AWS, suggesting that modifying flow regimes does alter in-stream habitats at varying spatial scales and may influence life-history strategies. Substantial fragmentation in suitable pool availability and loss of longitudinal connectivity exhibited by dry season flow suggested a higher risk of adverse biological effects during the dry season, which may reduce population viability by reducing survivorship and reproduction failure. Owing to river dolphins' dependence on the attribute of freshwater flow, they can be expected to be more affected by flow regulations as interactive effects. Considering the seasonal effects and changes in the availability of usable areas by flow alteration, adopting effective habitat retention plans by water-based development projects appears critical to avoid further ecological risks in aquatic species conservation. Identifying priority riverscapes for river cetaceans and prioritizing investment opportunities is an essential first step towards effective riverine cetacean conservation. © 2021 Paudel et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Thermal evaluation of a greenhouse in a remote high altitude area of Nepal

Remote communities in the high altitude areas of Nepal suffer both chronic and acute malnutrition. This is due to a shortage of arable land and a harsh climate. For seven months of the year, the harvesting of fresh vegetables is almost impossible. Greenhouse technology, if appropriate for the location and its community, can extend the growing season considerably. Experience in the Ladakh region of India indicates that year-round cropping is possible in greenhouses in cold mountainous areas. A simple 50-m2 greenhouse has been constructed in Simikot, the main town of Humla, northwest Nepal. This paper describes the evaluation of the thermal performance of that greenhouse. Both measurement and simulation were used in the evaluation. Measurements during the winter of 2006-7 indicate that the existing design is capable of producing adequate growing conditions for some vegetable crops, but that improvements are required if crops like tomatoes are to be grown successfully. Options to improve the thermal performance of the greenhouse have been investigated by simulation. Improvements to the building envelope such as wall insulation, double-glazing and using a thermal screen were simulated with a validated TRNSYS model. The impact of the addition of nighttime heat from internal passive solar water collectors was also predicted. The simulations indicate that the passive solar water collectors would raise the average greenhouse air temperature by 2.5°C and the overnight air temperature would increase by 4.0°C. When used in combination, overnight temperatures are predicted to by almost 7°C higher

Ecological responses to flow variation inform river dolphin conservation

Many environmental flow (e-flow) studies and applications have predominantly used state—(i.e., at a single time point) and rate—(i.e., temporal change) based demographic characteristics of species representing lower trophic levels (e.g., fish communities) to build flow-ecology relationships, rather than using a process that incorporates population dynamics. Recent studies have revealed the importance of incorporating data on species traits when building flow-ecology relationships. The effects of flow on keystone megafauna species (i.e., body mass ≥ 30 kg) reverberate through entire food webs; however, the relationships between flow and these species are not well understood, limiting the scope of the relationships used in flow management. Here, we fill this gap by incorporating the habitat selection traits at different flows of a freshwater apex predator, Ganges River dolphin (GRD, Platanista gangetica gangetica), which plays a significant role in maintaining the structure, functions and integrity of the aquatic ecosystem. Using temporally and spatially measured GRD habitat selection traits, we quantified flow-ecology responses in the Karnali River of Nepal during the low-flow season when habitat was heavily reduced and water demand was highest. We define ecological responses as suitable habitat templates with enough usable surface area to support GRD fitness by improving reproduction and survival. We measured the available and occupied habitats to develop flow-ecology responses. Variation in flow resulted in substantial differences in the ecological response across time and space, suggesting that aquatic species adjusted in a variety of habitats to support their life histories and maintain viable populations. The limited availability of suitable habitats combined with uninformed water regulations by humans likely places GRDs under severe physiological stress during low-water seasons (i.e., January–April), suggesting that reduced flows contribute to the process of endangering and extirpating highly sensitive endemic aquatic biodiversity. Our study reveals that ad hoc or experience-based flow management is no longer tenable to maintain the integrity and functionality of aquatic ecosystems. We stress that quantifying the flow-ecology relationships of foundational species, particularly megafauna, in response to flow variation is crucial for monitoring the effects of water alterations and determining the minimum flows needed for maintaining healthy and functional freshwater ecosystems in the Anthropocene. © 2020, The Author(s).Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Behavioral responses to spatial heterogeneity in endangered Ganges River dolphins (Platanista gangetica gangetica)

Globally, the threat of endangerment and extinction of small cetaceans was highlighted after the recent extinction of the Chinese River dolphin or Baiji (Lipotes vexillifer). Species with a small population size and a limited geographic range, such as Ganges River dolphins (GRD), are more vulnerable to extinction. The social and behavioral needs of cetaceans have been identified as potential factors increasing their vulnerability to human disturbance. However, little is known about how GRD adapt their behaviors and diel activity patterns to spatiotemporal variation. In this paper, we examined the underwater behavior of GRDs in Nepal by collecting echolocation clicks from three spatially stratified habitats in the Sapta Koshi River system over a six-month period. Our research found that GRDs behave differently in response to spatial heterogeneity, indicating diverse environmental requirements for GRD persistence. Behavioral activity and duration varied across habitats but not across time of day, suggesting that GRD behaviors are likely to be regulated by habitat structure regardless of the time of day. However, GRD consistently exhibited nocturnal activity peaks even when diurnal activity varied substantially. This indicates that river dolphins may favor nocturnal refuges as a reaction to human disturbance in highly regulated rivers. Managing human disturbances in conjunction with habitat heterogeneity can improve the persistence of riverine cetaceans. Here, we document behavioral and ecological information pertaining to GRD, which is essential to the formation of river dolphin recovery plans that link ecological perspectives to planning and management. © 2022 The AuthorsOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]