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Modeling water resources under competing demands for sustainable development: A case study of Kaligandaki Gorge Hydropower Project in Nepal

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Water Science and Engineering 2019年第1期12卷 19-26页

作者： Rakesh Sahukhal Tri ratna bajracharya Energy Environment Research and Development CentreLalitpur 44602Nepal Institute of Engineering Department of Mechanical EngineeringTribhuwan UniversityLalitpur 44600Nepal

The challenges posed by climate change require that the quantity and quality of water resources in Nepal be managed with sustainable development practices. The communities around the Kaligandaki Gorge Hydropower Project in the Myagdi District of Nepal depend on river flow for most of their rural and agricultural needs. Without a sustainable development plan, the growing population of the region, confined in an area with declining water resources, will face serious challenges to economic growth. Meteorological data show increasing annual average rainfall at a slight rate of about 0.284 mm/year, with erratic annual percentage change in rainfall in the area. The mean and minimum temperatures show decreasing trends at the rates of 0.05-C and 0.14-C per year, respectively. An assessment of the impacts on water availability for domestic and irrigation usage in the face of competing demands caused by the hydropower development project in the Kaligandaki Gorge was undertaken. The water demand and supply modeling were conducted using the water evaluation and planning (WEAP) model, based on discharge data from the Kaligandaki River, which were obtained from the Department of Hydrology and Meteorology, Nepal. The available data from 2001 to 2003 were used to estimate the model parameters while the stability of these parameters was tested with a validation period from 2004 to 2007. The performance of the model was assessed through statistical measures of calibration with the root mean square error and coefficient of determination, whose values were 0.046% and 0.79, respectively. Two scenarios were created in addition to the base case scenario: the discharge decrement scenario and new irrigation technology scenario. Analysis showed that a prioritization of demands will be necessary in the area in the near future for the purpose of sustainability of water resources, due to climate change impacts.

关键词： Climate change Competing demands Sustainable development Hydropower project WEAP

Validation of the Satellite-Derived Rainfall Estimates over the Tibet

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Acta meteorologica Sinica 2011年第6期25卷 734-741页

作者：除多普布顿珠罗布坚参 sagar bajracharya MANDIRA Shrestha 郭建平 Institute of Plateau Meteorology CMA Tibet Institute of Plateau Atmospheric and Environmental Sciences Tibet Weather Observatory Tibet Meteorological Service International Centre for Integrated Mountain Development (ICIMOD) Chinese Academy of Meteorological Sciences CMA

Measuring rainfall from space appears to be the only cost effective and viable means in estimating regional precipitation over the Tibet, and the satellite rainfall products are essential to hydrological and agricultural modeling. A long-standing problem in the meteorological and hydrological studies is that there is only a sparse raingauge network representing the spatial distribution of precipitation and its quantity on small scales over the Tibet. Therefore, satellite derived quantitative precipitation estimates are extremely usefill for obtaining rainfall patterns that can be used by hydrological models to produce forecasts of river discharge and to delineate the flood hazard area. In this paper, validation of the US National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） RFE （rainfall estimate） 2.0 data was made by using daily rainfall observations at 11 weather stations over different climate zones from southeast to northwest of the Tibet during the rainy season from 1 June to 30 September 2005 and 2006. Analysis on the time series of daily rainfall of RFE-CPC and observed data in different climate zones reveals that the mean correlation coefficients between satellite estimated and observed rainfall is 0.74. Only at Pali and Nielamu stations located in the southern brink of the Tibet along the Himalayan Mountains, are the correlation coefficients less than 0.62. In addition, continuous validations show that the RFE performed well in different climate zones, with considerably low mean error （ME） and root mean square error （RMSE） scores except at Nielamu station along the Himalayan range. Likewise, for the dichotomous validation, at most stations over the Tibet, the probability of detection （POD） values is above 73% while the false alarm rate （FAR） is between 1% and 12%. Overall, NOAA CPC RFE 2.0 products performed well in the estimation and monitoring of rainfall over the Tibet and can be used to analyze the precipitation pattern,

关键词： precipitation validation satellite rainfall estimation Tibetan Plateau

Decadal glacial lake changes in the Koshi basin, central Himalaya, from 1977 to 2010, derived from Landsat satellite images

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Journal of Mountain Science 2017年第10期14卷 1969-1984页

作者： Finu SHRESTHA GAO Xiao Narendra Raj KHANAL Sudan Bikash MAHARJAN Rajendra Bahadur SHRESTHA WU Li-zong Pradeep Kumar MOOL Samjwal ratna bajracharya International Centre for Integrated Mountain Development (ICIMOD) 44600 Kathmandu Nepal Cold and Arid Regions Environmental and Engineering Research Institute (CAREERI) CAS Lanzhou 730000 China Central Department of Geography Tribhuvan University 44600 Kirtipur Nepal Polar Research Institute of China Shanghai 200135 China

Changes in glacial lakes and the consequences of these changes, particularly on the development of water resources and management of glacial lake outburst flood(GLOF) risk, has become one of the challenges in the sustainable development of high mountain areas in the context of global warming. This paper presents the findings of a study on the distribution of, and area changes in, glacial lakes in the Koshi basin in the central *** on the number of glacial lakes and their area was generated for the years 1977, 1990, 2000, and 2010 using Landsat satellite images. According to the glacial lake inventory in 2010, there were a total of 2168 glacial lakes with a total area of 127.61 km^2 and average size of 0.06 km^2 in the Koshi basin. Of these,47% were moraine dammed lakes, 34.8% bedrock dammed lakes and 17.7% ice dammed lakes. The number of glacial lakes increased consistently over the study period from 1160 in 1977 to 2168 in 2010, an overall growth rate of 86.9%. The area of glacial lakes also increased from 94.44 km^2 in 1977 to 127.61 km^2 in 2010, a growth rate of 35.1%. A large number of glacial lakes in the inventory are small in size(≤ 0.1km^2). End moraine dammed lakes with area greater than 0.1 km^2 were selected to analyze the change characteristics of glacial lakes in the basin. The results show that, in 2010, there were 129 lakes greater than 0.1 km^2 in area; these lakes had a total area of 42.92km^2 in 1997, increasing to 63.28 km^2 in 2010. The distribution of lakes on the north side of the Himalayas(in China) was three times higher than on the south side of the Himalayas(in Nepal).Comparing the mean growth rate in area for the 33 year study period(1977-2010), the growth rate on the north side was found to be a little slower than that on the south side. A total of 42 glacial lakes with an area greater than 0.2 km^2 are rapidly growing between 1977 and 2010 in the Koshi basin, which need to be paid more attention to monitoring in the future an

关键词： Glacial lake Decadal glacial lake GLOF Inventory Landsat Koshi basin Nepal China

Erratum to:Decadal glacial lake changes in the Koshi basin,central Himalaya,from 1977 to 2010,derived from Landsat satellite images

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Journal of Mountain Science 2022年第8期19卷 2449-2450页

作者： Finu SHRESTHA GAO Xiao Narendra Raj KHANAL Sudan Bikash MAHARJAN Rajendra Bahadur SHRESTHA WU Li-zong Pradeep Kumar MOOL Samjwal ratna bajracharya International Centre for Integrated Mountain Development(ICIMOD) 44600 KathmanduNepal Cold and Arid Regions Environmental and Engineering Research Institute(CAREERI) CASLanzhou 730000China Central Department of Geography Tribhuvan University44600 KirtipurNepal Polar Research Institute of China Shanghai 200135China

The article Decadal glacial lake changes in the Koshi basin,central Himalaya,from 1977 to 2010,derived from Landsat satellite images,written by Finu SHRESTHA,GAO Xiao,Narendra Raj KHANAL,Sudan Bikash MAHARJAN,Rajendra Bahadur SHRESTHA,WU Li-zong,Pradeep Kumar MOOL and Samjwal ratna bajracharya,was originally erroneously published electronicaliy on the publisher's internet portal(currently SpringerLink)on 04 October 2017 without open access.

关键词： glacial basin images

GeoSFM水文模型在西藏拉萨河流域的应用

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山地学报 2015年第6期33卷 751-758页

作者：除多达平向莉英罗布坚参 Shrestha Mandira bajracharya sagar 中国气象局成都高原气象研究所拉萨分部西藏高原大气环境科学研究所西藏自治区水文水资源勘测局西藏自治区气象台国际山地综合发展中心(ICIMOD)

基于物理过程的半分布式水文模型USGS Geo SFM(Geospatial Stream Flow Model)对拉萨河2005年1—12月日径流量进行了模拟,并与同期的观测资料进行了对比。结果表明,Geo SFM模型在拉萨河流域的模拟效果较好,Nash-Sutcliffe效率系数为0.72... 详细信息

基于物理过程的半分布式水文模型USGS Geo SFM(Geospatial Stream Flow Model)对拉萨河2005年1—12月日径流量进行了模拟,并与同期的观测资料进行了对比。结果表明,Geo SFM模型在拉萨河流域的模拟效果较好,Nash-Sutcliffe效率系数为0.72,模拟和观测值之间的线性相关系数达0.89。由于Geo SFM模型输入参数较少,很多可以从应用广泛的全球或大尺度数据中获取,尤其是卫星遥感降水估算产品直接可以作为模型的降水驱动参数,所以在没有或缺少水文气象观测资料的地区应用前景广阔。

关键词：水文模型 GeoSFM 拉萨河西藏

Influence of heat treatment on the machinability and corrosion behavior of AZ91 Mg alloy

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Journal of Magnesium and Alloys 2018年第1期6卷 52-58页

作者： Swetha Chowdary V Ravikumar Dumpala Anand Kumar S Kondaiah VV ratna Sunil B Department of Mechanical Engineering Rajiv Gandhi University of Knowledge Technologies(AP-IIIT)Nuzvid521202India Department of Mechanical Engineering Visvesvaraya National Institute of TechnologyNagpurMaharashtra 440010India Department of Mechanical Engineering Dayananda Sagar UniversityBengaluru560068India Department of Mechanical Engineering Tirumala Engineering CollegeNarasaraopetAndhra Pradesh 522601India

In the present study,AZ91 Mg alloy was heat treated at 410℃ for 6,12 and 24 h to investigate the influence of heat treatment on machinability and corrosion *** effect of soaking time on the amount and distribution of Mg 17 Al 12(β-phase)was analyzed under the optical *** measurements demonstrated the increased hardness with increased heat treatment soaking time,which can be attributed to the solid solution *** influence of super saturatedα-grains on reducing the cutting force(F z)with respect to increased cutting speed was observed as *** corrosion behavior of the heat treated specimens was studied by conducting electrochemical ***,corrosion rate of heat treated samples was observed as increased compared with the base *** the results,it is evident that the machinability of AZ91 Mg alloy can be improved by producing super saturatedα-grains through heat treatment but at the cost of losing corrosion resistance.

关键词： AZ91 Mg alloy Solid solution Turning Corrosion Machinability