Assessment of potential outburst floods from the Tsho Rolpa glacial lake in Nepal   总被引：1，自引：1，他引：0  

Badri Bhakta Shrestha  Hajime Nakagawa 《Natural Hazards》2014,71(1):913-936

Flood and sediment disasters caused by glacial lake outbursts have occurred frequently in recent years in the Himalayas of Nepal. Glacial lake outburst floods (GLOFs) can cause catastrophic flooding in downstream areas with serious damage to lives and property. It is thus important to investigate outburst floods from potentially dangerous glacial lakes. In this study, the characteristics of potential outburst floods from the Tsho Rolpa glacial lake due to two types of moraine dam failure caused by seepage flow or water overtopping were analyzed with various scenarios by using integrated modeling system of three numerical models: (1) the flow and bed-surface erosion model, (2) the seepage model and (3) the slope stability model. Flood inundation areas were also identified by using the numerical model of the flow and moraine dam failure and geographical information system tools. Possible threats and damages due to the potential GLOF events from the lake were also analyzed based on numerical results, flood inundation maps and field investigations.  相似文献   

Spatio-temporal trend mapping of precipitation and its extremes across Afghanistan (1951–2010)     

Aliyar  Qurban  Dhungana  Santosh  Shrestha  Sangam 《Theoretical and Applied Climatology》2022,147(1-2):605-626

Theoretical and Applied Climatology - The civil war, harsh climate, tough topography, and lack of accurate meteorological stations have limited observed data across Afghanistan. To fulfill the gap,...  相似文献   

Methodological Advances in the Spatial Analysis of Land Fragmentation   总被引：1，自引：0，他引：1  

Sainan Zhang  Abigail M. York  Christopher G. Boone  Milan Shrestha 《The Professional geographer》2013,65(3):512-526

This article evaluates the effect of moving window (MW) size on observed fragmentation spatial patterns and proposes a method to identify an effective MW size using Simpson's diversity index. To test the robustness of the proposed method, we demonstrate its use in six cities in the Phoenix metropolitan area that have substantial variation in land composition and configuration. Next we explore the effects of gradient observation scale and the role of scale in removing noise. We compare and discuss two popular approaches to measuring urban-to-rural fragmentation gradients—concentric ring- and transect-based approaches—highlighting the usefulness of each approach in an extensive and rapidly urbanizing region. This study provides a new method for selecting window size, offers insights on scale effects, and provides guidance on gradient scale selection to achieve the best representation of land fragmentation patterns for urban analysis.  相似文献   

Shaking table tests of steel frame with superelastic Cu–Al–Mn SMA tension braces          下载免费PDF全文

Yoshikazu Araki  Kshitij C. Shrestha  Nao Maekawa  Yuji Koetaka  Toshihiro Omori  Ryosuke Kainuma 《地震工程与结构动力学》2016,45(2):297-314

Shaking table tests are performed on a one‐bay one‐story steel frame with superelastic Cu–Al–Mn shape memory alloy (SMA) tension braces. The frame is subjected to a series of scaled ground motions recorded during the 1995 Kobe earthquake, Japan. The test results demonstrate that the SMA braces are effective to prevent residual deformations and pinching. It is also shown that the time history responses observed from the shaking table tests agree well with the numerical predictions using a rate‐independent piecewise‐linear constitutive model calibrated to the quasi‐static component tests of the SMA braces. This suggests that the loading rate dependence of Cu–Al–Mn SMAs as well as the modeling error due to the piecewise linear approximation can be neglected in capturing the global response of the steel frame. Numerical simulations under a suite of near‐fault ground motion records are further performed using the calibrated analytical models to demonstrate the effectiveness of the SMA braces when the variability of near‐fault ground motions is taken into account. A stopper, or a deformation restraining device, is also proposed to prevent premature fracture of SMA bars in unexpectedly large ground motions while keeping the self‐centering capability in moderate to large ground motions. The effectiveness of the stopper is also demonstrated in the quasi‐static component and shaking table tests. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Assessing flood disaster impacts in agriculture under climate change in the river basins of Southeast Asia   总被引：1，自引：0，他引：1  

Shrestha  Badri Bhakta  Perera  Edangodage Duminda Pradeep  Kudo  Shun  Miyamoto  Mamoru  Yamazaki  Yusuke  Kuribayashi  Daisuke  Sawano  Hisaya  Sayama  Takahiro  Magome  Jun  Hasegawa  Akira  Ushiyama  Tomoki  Iwami  Yoichi  Tokunaga  Yoshio 《Natural Hazards》2019,97(1):157-192

Natural Hazards - This study focused on flood damage assessment for future floods under the impact of climate change. Four river basins of Southeast Asia were selected for the study. They included...  相似文献   

Cryospheric hazards and risk perceptions in the Sagarmatha (Mt. Everest) National Park and Buffer Zone,Nepal     

Sherpa  Sonam Futi  Shrestha  Milan  Eakin  Hallie  Boone  Christopher G. 《Natural Hazards》2019,96(2):607-626

Glacial lake outburst floods (GLOFs) are among the most serious cryospheric hazards for mountain communities. Multiple studies have predicted the potential risks posed by rapidly expanding glacial lakes in the Sagarmatha (Mt. Everest) National Park and Buffer Zone of Nepal. People’s perceptions of such cryospheric hazards can influence their actions, beliefs, and responses to those hazards and associated risks. This study provides a systematic approach that combines household survey data with ethnography to analyze people’s perceptions of GLOF risks and the socioeconomic and cultural factors influencing their perceptions. A statistical logit model of household data showed a significant positive correlation between the perceptions of GLOF risks and livelihood sources, mainly tourism. Risk perceptions are also influenced by spatial proximity to glacial lakes and whether a village is in potential flood zones. The 2016 emergency remediation work implemented in the Imja Tsho (glacial lake) has served as a cognitive fix, especially in the low-lying settlements. Much of uncertainty and confusions related GLOF risks among locals can be attributed to a disconnect between how scientific information is communicated to the local communities and how government climate change policies have been limited to awareness campaigns and emergency remediation efforts. A sustainable partnership of scientists, policymakers, and local communities is urgently needed to build a science-driven, community-based initiative that focuses not just in addressing a single GLOF threat but develops on a comprehensive cryospheric risk management plan and considers opportunities and challenges of tourism in the local climate adaptation policies.

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Spatial and temporal variation in the trends of hydrological response of forested watersheds in Thailand     

Jessada Techamahasaranont  Sangam Shrestha  Mukand S. Babel  Rajendra P. Shrestha  Damien Jourdain 《Environmental Earth Sciences》2017,76(12):430

Thailand has undergone significant forest cover changes in recent decades, and this is likely to have altered the hydrological functioning of many watersheds; however, such potential impacts are not fully understood. To contribute towards a better understanding of the potential hydrological impacts of forest cover changes, this study examines the temporal trends of several hydrological indices in eight watersheds of Thailand over the period from 1982 to 2013. A number of hydrological indices (runoff coefficient, baseflow index, flow duration indices, streamflow elasticity, dryness index) were analysed using a combined Thiel–Sen/Mann–Kendall trend-testing approach, to assess the magnitude and significance of patterns in the observed data. These trend tests indicated that the change in the hydrological response of watersheds varied with the change in structure and composition of forest species. A significant increase in runoff (viz. average flow) was observed in those watersheds covered with natural forests, whereas a significant reduction in runoff (viz. baseflow and low runoff) was observed in those watersheds where the land cover was changed to Para rubber plantations and reforested areas. It is also noteworthy that the watersheds covered by natural forest showed more streamflow elasticity than plantations or reforested areas. These results highlight the importance of considering both forest types/dynamics and watershed characteristics when assessing hydrological impacts.  相似文献   

HUMAN RELATIONS AND PRIMARY HEALTH CARE DELIVERY IN RURAL NEPAL: THE CASE OF DEURALI *     

Nanda R. Shrestha 《The Professional geographer》1988,40(2):202-214

A preliminary analysis of the primary health care delivery component of a small rural development project in Deurali, Nepal, suggests that personal relations between project personnel and their target population (e.g., implementors'sincerity and commitment to service) can overcome many cultural, geographical, and class-related social barriers to achieving project objectives. The Deurali medical staff's ability to combine their technical skills with sincerity, hard work, and commitment has made the Deurali project reasonably successful in meeting villagers'primary health care needs.  相似文献   

Optimal selection of representative climate models and statistical downscaling for climate change impact studies: a case study of Rhode Island,USA     

Shrestha  Shiva Gopal  Pradhanang  Soni M. 《Theoretical and Applied Climatology》2022,149(1-2):695-708

Theoretical and Applied Climatology - The future climate impact studies rely on future projections obtained from downscaling of Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models....  相似文献   

Simulating land use for protecting food crop areas in northeast Thailand using GIS and Dyna-CLUE     

Sakayarote  Kanda  Shrestha  Rajendra P. 《地理学报(英文版)》2019,29(5):803-817

Journal of Geographical Sciences - Land use in the northeast region of Thailand has changed dramatically in the past two decades. These changes are mainly due to the government policies, which...  相似文献