Search

Your search keyword '"Immerzeel, Walter W."' showing total 346 results
Start Over Author "Immerzeel, Walter W."
346 results on '"Immerzeel, Walter W."'

2. The Great Glacier and Snow-Dependent Rivers of Asia and Climate Change: Heading for Troubled Waters

Author

Molden, David J., Shrestha, Arun B., Immerzeel, Walter W., Maharjan, Amina, Rasul, Golam, Wester, Philippus, Wagle, Nisha, Pradhananga, Saurav, Nepal, Santosh, Biswas, Asit K., Series Editor, Tortajada, Cecilia, Series Editor, Altinbilek, Dogan, Editorial Board Member, González-Gómez, Francisco, Editorial Board Member, Gopalakrishnan, Chennat, Editorial Board Member, Horne, James, Editorial Board Member, Molden, David J., Editorial Board Member, and Varis, Olli, Editorial Board Member

Published
2022
Full Text
View/download PDF

4. Snow depth variability in the Northern Hemisphere mountains observed from space.

Author

Lievens, Hans, Demuzere, Matthias, Marshall, Hans-Peter, Reichle, Rolf H, Brucker, Ludovic, Brangers, Isis, de Rosnay, Patricia, Dumont, Marie, Girotto, Manuela, Immerzeel, Walter W, Jonas, Tobias, Kim, Edward J, Koch, Inka, Marty, Christoph, Saloranta, Tuomo, Schöber, Johannes, and De Lannoy, Gabrielle JM

Abstract

Accurate snow depth observations are critical to assess water resources. More than a billion people rely on water from snow, most of which originates in the Northern Hemisphere mountain ranges. Yet, remote sensing observations of mountain snow depth are still lacking at the large scale. Here, we show the ability of Sentinel-1 to map snow depth in the Northern Hemisphere mountains at 1 km² resolution using an empirical change detection approach. An evaluation with measurements from ~4000 sites and reanalysis data demonstrates that the Sentinel-1 retrievals capture the spatial variability between and within mountain ranges, as well as their inter-annual differences. This is showcased with the contrasting snow depths between 2017 and 2018 in the US Sierra Nevada and European Alps. With Sentinel-1 continuity ensured until 2030 and likely beyond, these findings lay a foundation for quantifying the long-term vulnerability of mountain snow-water resources to climate change.

Published
2019

5. Quality Assessment of Multiple UAV-SfM DEMs Derived for Impact Assessment of a Co-Seismic Avalanche in the Himalayas.

Author

Sunako, Sojiro, Fujita, Koji, Yamaguchi, Satoru, Inoue, Hiroshi, Immerzeel, Walter W., Izumi, Takeki, and Kayastha, Rijan B.

Subjects
GLOBAL Positioning System, DIGITAL elevation models, RISK assessment, STANDARD deviations, EARTHQUAKES
Abstract

Combined with the structure from motion (SfM) technique, unmanned aerial vehicles (UAVs) are powerful tools for generating high-resolution digital elevation models (DEMs) for application in hazard assessments. During our field observations in October 2015 at Langtang Village, which was destroyed by the Gorkha earthquake in April 2015, three different UAVs with mounted cameras were operated to evaluate the volume of the avalanche deposit covering the village. This study evaluated the performance of DEMs created from the different cameras on board those UAVs. Multiple DEMs for the different cameras, including Sony-α7R (PA7), Ricoh-GR (XGR), and Canon-IXUS (EIX), were created using SfM software. All DEMs were compared with a base DEM created from differential global positioning system survey data, which was obtained simultaneously with the UAV campaigns. The results show that the elevation difference of PA7-, XGR-, and EIX-DEMs are within ±0.14 m; the standard deviations of elevation difference range from 0.33 to 0.40 m. Although there were slightly larger differences in elevation on the southwest-to-west sides of the XGR- and EIX-DEMs, which can be attributed mainly to the flight paths and ground control point network, our DEMs are still of high enough quality to be used in hazard assessments. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

6. Fate of Mountain Glaciers in the Anthropocene (2011) : A Report by the Working Group Commissioned by the Pontifical Academy of Sciences

Author

Ajai, Bengtsson, Lennart, Breashears, David, Crutzen, Paul J., Fuzzi, Sandro, Haeberli, Wilfried, Immerzeel, Walter W., Kaser, Georg, Kennel, Charles F., Kulkarni, Anil, Pachauri, Rajendra, Painter, Thomas H., Rabassa, Jorge, Ramanathan, Veerabhadran, Robock, Alan, Rubbia, Carlo, Russell, Lynn M., Sorondo, Marcelo Sánchez, Schellnhuber, Hans Joachim, Sorooshian, Soroosh, Stocker, Thomas F., Thompson, Lonnie G., Toon, Owen B., Zaelke, Durwood, Mittelstraß, Jürgen, Brauch, Hans Günter, Series Editor, Benner, Susanne, editor, Lax, Gregor, editor, Crutzen, Paul J., editor, Pöschl, Ulrich, editor, and Lelieveld, Jos, editor

Published
2021
Full Text
View/download PDF

10. From theoretical to sustainable potential for run-of-river hydropower development in the upper Indus basin

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Pradhananga, Saurav, Smolenaars, Wouter, Khanal, Sonu, Biemans, Hester, Nepal, Santosh, Ludwig, Fulco, Shrestha, Arun Bhakta, Immerzeel, Walter W., Hydrologie, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Pradhananga, Saurav, Smolenaars, Wouter, Khanal, Sonu, Biemans, Hester, Nepal, Santosh, Ludwig, Fulco, Shrestha, Arun Bhakta, and Immerzeel, Walter W.

Published
2024

12. Understanding the Asian water tower requires a redesigned precipitation observation strategy.

Author

Chiyuan Miao, Immerzeel, Walter W., Baiqing Xu, Kun Yang, Qingyun Duan, and Xin Li

Subjects
*HYDROLOGIC cycle, *WATERSHEDS, *RUNOFF, *PARADOX, *EVAPOTRANSPIRATION
Abstract

The Asian water tower (AWT) serves as the source of 10 major Asian river systems and supports the lives of ~2 billion people. Obtaining reliable precipitation data over the AWT is a prerequisite for understanding the water cycle within this pivotal region. Here, we quantitatively reveal that the "observed" precipitation over the AWT is considerably underestimated in view of observational evidence from three water cycle components, namely, evapotranspiration, runoff, and accumulated snow. We found that three paradoxes appear if the so-called observed precipitation is corrected, namely, actual evapotranspiration exceeding precipitation, unrealistically high runoff coefficients, and accumulated snow water equivalent exceeding contemporaneous precipitation. We then explain the cause of precipitation underestimation from instrumental error caused by wind-induced gauge undercatch and the representativeness error caused by sparse-uneven gauge density and the complexity of local surface conditions. These findings require us to rethink previous results concerning the water cycle, prompting the study to discuss potential solutions. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

17. Recent ground thermo-hydrological changes in a southern Tibetan endorheic catchment and implications for lake level changes.

Author

Martin, Léo C. P., Westermann, Sebastian, Magni, Michele, Brun, Fanny, Fiddes, Joel, Lei, Yanbin, Kraaijenbrink, Philip, Mathys, Tamara, Langer, Moritz, Allen, Simon, and Immerzeel, Walter W.

Subjects
METEOROLOGICAL stations, WATER supply, WATERSHEDS, FROZEN ground, GROUNDWATER, LAKES, PALEOHYDROLOGY
Abstract

Climate change modifies the water and energy fluxes between the atmosphere and the surface in mountainous regions such as the Qinghai–Tibet Plateau (QTP), which has shown substantial hydrological changes over the last decades, including rapid lake level variations. The ground across the QTP hosts either permafrost or is seasonally frozen, and, in this environment, the ground thermal regime influences liquid water availability, evaporation and runoff. Consequently, climate-induced changes in the ground thermal regime may contribute to variations in lake levels, but the validity of this hypothesis has yet to be established. This study focuses on the cryo-hydrology of the catchment of Lake Paiku (southern Tibet) for the 1980–2019 period. We process ERA5 data with downscaling and clustering tools (TopoSCALE, TopoSUB) to account for the spatial variability of the climate in our forcing data (Fiddes and Gruber, 2012, 2014). We use a distributed setup of the CryoGrid community model (version 1.0) to quantify thermo-hydrological changes in the ground during this period. Forcing data and simulation outputs are validated with data from a weather station, surface temperature loggers and observations of lake level variations. Our lake budget reconstruction shows that the main water input to the lake is direct precipitation (310 mmyr-1), followed by glacier runoff (280 mmyr-1) and land runoff (180 mmyr-1). However, altogether these components do not offset evaporation (860 mmyr-1). Our results show that both seasonal frozen ground and permafrost have warmed (0.17 ∘C per decade 2 m deep), increasing the availability of liquid water in the ground and the duration of seasonal thaw. Correlations with annual values suggest that both phenomena promote evaporation and runoff. Yet, ground warming drives a strong increase in subsurface runoff so that the runoff / (evaporation + runoff) ratio increases over time. This increase likely contributed to stabilizing the lake level decrease after 2010. Summer evaporation is an important energy sink, and we find active-layer deepening only where evaporation is limited. The presence of permafrost is found to promote evaporation at the expense of runoff, consistently with recent studies suggesting that a shallow active layer maintains higher water contents close to the surface. However, this relationship seems to be climate dependent, and we show that a colder and wetter climate produces the opposite effect. Although the present study was performed at the catchment scale, we suggest that this ambivalent influence of permafrost may help to understand the contrasting lake level variations observed between the south and north of the QTP, opening new perspectives for future investigations. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

18. Recent ground thermo-hydrological changes in a southern Tibetan endorheic catchment and implications for lake level changes

Author

Hydrologie, Martin, Léo C. P., Westermann, Sebastian, Magni, Michele, Brun, Fanny, Fiddes, Joel, Lei, Yanbin, Kraaijenbrink, Philip, Mathys, Tamara, Langer, Moritz, Allen, Simon, Immerzeel, Walter W., Hydrologie, Martin, Léo C. P., Westermann, Sebastian, Magni, Michele, Brun, Fanny, Fiddes, Joel, Lei, Yanbin, Kraaijenbrink, Philip, Mathys, Tamara, Langer, Moritz, Allen, Simon, and Immerzeel, Walter W.

Published
2023

19. Quantification of run-of-river hydropower potential in the Upper Indus basin under climate change

Author

Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, Immerzeel, Walter W., Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, and Immerzeel, Walter W.

Abstract

Introduction: Despite ambitious plans to quadruple hydropower generation in the Indus basin, a quantitative assessment of the impact of climate change on hydropower availability in the basin is missing. To address this gap, we combine downscaled CMIP6 projections with the Hydropower Potential Exploration (HyPE) model to quantify future hydropower potential available in the upper Indus basin. Methods: HyPE uses a spatial cost-minimization framework to evaluate four classes of hydropower potential, namely theoretical, technical, financial and sustainable, considering various constraints on the siting and sizing of two run-of-river hydropower plant configurations. Results: Under future discharge projections, all classes of potential increase while subbasin changes align with the spatial patterns projected in hydro-climatology. Theoretical potential changes by 3.9–56 %, technical potential by −2.3–46.8 %, financial potential by −8.8–50.4 % and sustainable potential by −6.1–49.7 %. A small decline is observed in the northwestern subbasins where increase in potential is lower than in the southeast. In contrast, with increasing variability in the Indian Summer Monsoon in the future, the southeastern subbasins have the strongest increase in sustainable potential accompanied by higher increase in plant size, decrease in costs and higher variability. The southeastern Satluj subbasin is the hotspot where sustainable potential has the highest increase of up to 145 %. The northwestern Kabul subbasin has the highest decrease of up to −27 %. The Swat subbasin has the lowest variability in sustainable potential while the Jhelum and Indus main subbasins remain the subbasins with the cheapest potential into the future. The performance of future sustainable portfolios differ from the performance of historical portfolios by −11.1–39.9 %. Discussion: Hence, considering future climate in the present-day planning of hydropower will lead to improved performance under a majority of scenario

Published
2023

20. Preprocessed input files for HyPE model for Upper Indus basin

Author

Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, Immerzeel, Walter W., Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, and Immerzeel, Walter W.

Abstract

This archive contains preprocessed input data file setup for running the Hydropower Potential Exploration (HyPE) model for the Upper Indus basin. It contains inputs for running historical or future discharge scenarios. Preprocessed data are based on publicly available datasets described in supporting papers., This archive contains preprocessed input data file setup for running the Hydropower Potential Exploration (HyPE) model for the Upper Indus basin. It contains inputs for running historical or future discharge scenarios. Preprocessed data are based on publicly available datasets described in supporting papers.

Published
2023

21. Quantification of run-of-river hydropower potential in the Upper Indus basin under climate change

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, Immerzeel, Walter W., Hydrologie, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Smolenaars, Wouter Julius, Khanal, Sonu, Jamil, Muhammad Khalid, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun Bhakta, and Immerzeel, Walter W.

Published
2023

23. Critical Role of Groundwater Inflow in Sustaining Lake Water Balance on the Western Tibetan Plateau

Author

Lei, Yanbin, Yang, Kun, Immerzeel, Walter W., Song, Peiping, Bird, Broxton W., He, Jiankun, Zhao, Huabiao, Li, Zhiguo, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Hydrologie, and Landscape functioning, Geocomputation and Hydrology

Subjects
Geophysics, General Earth and Planetary Sciences, Earth and Planetary Sciences(all)
Abstract

It is difficult to quantify the amount of groundwater inflow on the Tibetan Plateau (TP), yet it can be critically important for sustaining lake water balance. Here we show that most endorheic lakes on the western TP exhibited considerable water level increase during the ice-covered period, which contrasts with lakes in other regions of the TP. An analysis of lake water balance attributes this water surplus to significant groundwater inflow, which is estimated to be about 59%–66% of total inflow into lakes. The groundwater inflow occurred after the 2000s, which is consistent with the rapid lake expansion and significant increase in precipitation. We suggest that the groundwater inflow is mainly related to large-scale active faults in the limestone bedrock and sufficient meltwater from high elevations. Our results imply that groundwater may be deeply involved in the water cycle and modify the seasonal and inter-annual lake variations on the western TP.

Published
2022

24. Progress and challenges in glacial lake outburst flood research (2017–2021): a research community perspective

Author

Emmer, Adam, primary, Allen, Simon K., additional, Carey, Mark, additional, Frey, Holger, additional, Huggel, Christian, additional, Korup, Oliver, additional, Mergili, Martin, additional, Sattar, Ashim, additional, Veh, Georg, additional, Chen, Thomas Y., additional, Cook, Simon J., additional, Correas-Gonzalez, Mariana, additional, Das, Soumik, additional, Diaz Moreno, Alejandro, additional, Drenkhan, Fabian, additional, Fischer, Melanie, additional, Immerzeel, Walter W., additional, Izagirre, Eñaut, additional, Joshi, Ramesh Chandra, additional, Kougkoulos, Ioannis, additional, Kuyakanon Knapp, Riamsara, additional, Li, Dongfeng, additional, Majeed, Ulfat, additional, Matti, Stephanie, additional, Moulton, Holly, additional, Nick, Faezeh, additional, Piroton, Valentine, additional, Rashid, Irfan, additional, Reza, Masoom, additional, Ribeiro de Figueiredo, Anderson, additional, Riveros, Christian, additional, Shrestha, Finu, additional, Shrestha, Milan, additional, Steiner, Jakob, additional, Walker-Crawford, Noah, additional, Wood, Joanne L., additional, and Yde, Jacob C., additional

Published
2022
Full Text
View/download PDF

26. Spatial and temporal patterns of snowmelt refreezing in a Himalayan catchment

Author

Veldhuijsen, Sanne B.M., De Kok, Remco J., Stigter, Emmy E., Steiner, Jakob F., Saloranta, Tuomo M., Immerzeel, Walter W., Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, Hydrologie, Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, and Hydrologie

Subjects
geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, snowmelt, Himalaya, 0207 environmental engineering, Drainage basin, modeling, 02 engineering and technology, 15. Life on land, 01 natural sciences, Catchment, 13. Climate action, Snowmelt, snow hydrology, Environmental science, Physical geography, 020701 environmental engineering, Geology, 0105 earth and related environmental sciences, refreezing, Earth-Surface Processes
Abstract

Seasonal snow contributes significantly to the annual runoff in the Himalaya and both timing and volume are important for downstream users. In polar regions, meltwater refreezing within snowpacks has been well-studied. While the conditions in the Himalaya are considered favorable for refreezing, little is known about refreezing in this region, hindering a complete understanding of seasonal snowmelt dynamics. In this study, we simulated refreezing with the seNorge (v2.0) snow model for the Langtang catchment in the Nepalese Himalaya covering a 5-year period. Thereby, we aim to improve our understanding about how refreezing varies in space and time and to provide a framework for future snow modeling studies. The first part of this study focuses extensively on developing meteorological forcing data, which were derived from an unique elaborate network of meteorological stations and high-resolution meteorological simulations. The snow model was validated against in-situ snow observations and snow cover satellite data. In the second part of this study, we analyze the spatial and temporal refreezing patterns, and attempt to identify possible driving factors. The results show that the annual average refreezing amounts to 122 mm (21% of the total melt). We found that the magnitude of refreezing varies strongly in space depending on elevation and aspect. In addition, there is a strong seasonal altitudinal variability related to air temperature and snow depth, with most refreezing during the early melt season. We also found a substantial intra-annual variability, which mainly results from fluctuations of snowfall, highlighting the importance of using multi-year time series in refreezing assessments. Daily refreezing simulations decreased by 84% (to an average 19 mm year-1) compared to hourly simulations, emphasizing the importance of using sub-daily time steps to capture diurnal melt-refreeze cycles. Climate sensitivity experiments revealed that refreezing is highly sensitive to future changes in air temperature, as a temperature increase of 2°C leads to a refreezing decrease of 35%. We conclude that including refreezing with a sub-daily temporal resolution is highly relevant for understanding snow dynamics in the current and future climate of the Himalaya.

Published
2022

27. High Mountain Asia hydropower systems threatened by climate-driven landscape instability

Author

Sub Process Management and Analytics, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Li, Dongfeng, Lu, Xixi, Walling, Desmond E., Zhang, Ting, Steiner, Jakob F., Wasson, Robert J., Harrison, Stephan, Nepal, Santosh, Nie, Yong, Immerzeel, Walter W., Shugar, Dan H., Koppes, Michèle, Lane, Stuart, Zeng, Zhenzhong, Sun, Xiaofei, Yegorov, Alexandr, Bolch, Tobias, Sub Process Management and Analytics, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Li, Dongfeng, Lu, Xixi, Walling, Desmond E., Zhang, Ting, Steiner, Jakob F., Wasson, Robert J., Harrison, Stephan, Nepal, Santosh, Nie, Yong, Immerzeel, Walter W., Shugar, Dan H., Koppes, Michèle, Lane, Stuart, Zeng, Zhenzhong, Sun, Xiaofei, Yegorov, Alexandr, and Bolch, Tobias

Published
2022

28. Progress and challenges in glacial lake outburst flood research (2017-2021): a research community perspective

Author

Leerstoel Dijkerman, LS Moderne letterkunde Engels, ICON - Modern and Contemporary Literature, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Emmer, Adam, Allen, Simon K., Carey, Mark, Frey, Holger, Huggel, Christian, Korup, Oliver, Mergili, Martin, Sattar, Ashim, Veh, Georg, Chen, Thomas Y., Cook, Simon J., Correas-Gonzalez, Mariana, Das, Soumik, Diaz Moreno, Alejandro, Drenkhan, Fabian, Fischer, Melanie, Immerzeel, Walter W., Izagirre, Eñaut, Joshi, Ramesh Chandra, Kougkoulos, Ioannis, Kuyakanon Knapp, Riamsara, Li, Dongfeng, Majeed, Ulfat, Matti, Stephanie, Moulton, Holly, Nick, Faezeh, Piroton, Valentine, Rashid, Irfan, Reza, Masoom, Ribeiro De Figueiredo, Anderson, Riveros, Christian, Shrestha, Finu, Shrestha, Milan, Steiner, Jakob, Walker-Crawford, Noah, Wood, Joanne L., Yde, Jacob C., Leerstoel Dijkerman, LS Moderne letterkunde Engels, ICON - Modern and Contemporary Literature, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Emmer, Adam, Allen, Simon K., Carey, Mark, Frey, Holger, Huggel, Christian, Korup, Oliver, Mergili, Martin, Sattar, Ashim, Veh, Georg, Chen, Thomas Y., Cook, Simon J., Correas-Gonzalez, Mariana, Das, Soumik, Diaz Moreno, Alejandro, Drenkhan, Fabian, Fischer, Melanie, Immerzeel, Walter W., Izagirre, Eñaut, Joshi, Ramesh Chandra, Kougkoulos, Ioannis, Kuyakanon Knapp, Riamsara, Li, Dongfeng, Majeed, Ulfat, Matti, Stephanie, Moulton, Holly, Nick, Faezeh, Piroton, Valentine, Rashid, Irfan, Reza, Masoom, Ribeiro De Figueiredo, Anderson, Riveros, Christian, Shrestha, Finu, Shrestha, Milan, Steiner, Jakob, Walker-Crawford, Noah, Wood, Joanne L., and Yde, Jacob C.

Published
2022

29. Spatial and temporal patterns of snowmelt refreezing in a Himalayan catchment

Author

Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, Hydrologie, Veldhuijsen, Sanne B.M., De Kok, Remco J., Stigter, Emmy E., Steiner, Jakob F., Saloranta, Tuomo M., Immerzeel, Walter W., Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, Hydrologie, Veldhuijsen, Sanne B.M., De Kok, Remco J., Stigter, Emmy E., Steiner, Jakob F., Saloranta, Tuomo M., and Immerzeel, Walter W.

Published
2022

30. Critical Role of Groundwater Inflow in Sustaining Lake Water Balance on the Western Tibetan Plateau

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Lei, Yanbin, Yang, Kun, Immerzeel, Walter W., Song, Peiping, Bird, Broxton W., He, Jiankun, Zhao, Huabiao, Li, Zhiguo, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Lei, Yanbin, Yang, Kun, Immerzeel, Walter W., Song, Peiping, Bird, Broxton W., He, Jiankun, Zhao, Huabiao, and Li, Zhiguo

Published
2022

31. The Great Glacier and Snow-Dependent Rivers of Asia and Climate Change: Heading for Troubled Waters

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Molden, David J., Shrestha, Arun B., Immerzeel, Walter W., Maharjan, Amina, Rasul, Golam, Wester, Philippus, Wagle, Nisha, Pradhananga, Saurav, Nepal, Santosh, Biswas, Asit K., Tortajada, Cecilia, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Molden, David J., Shrestha, Arun B., Immerzeel, Walter W., Maharjan, Amina, Rasul, Golam, Wester, Philippus, Wagle, Nisha, Pradhananga, Saurav, Nepal, Santosh, Biswas, Asit K., and Tortajada, Cecilia

Published
2022

32. High Mountain Asia hydropower systems threatened by climate-driven landscape instability

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Li, Dongfeng, Lu, Xixi, Walling, Desmond E., Zhang, Ting, Steiner, Jakob F., Wasson, Robert J., Harrison, Stephan, Nepal, Santosh, Nie, Yong, Immerzeel, Walter W., Shugar, Dan H., Koppes, Michèle, Lane, Stuart, Zeng, Zhenzhong, Sun, Xiaofei, Yegorov, Alexandr, Bolch, Tobias, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Li, Dongfeng, Lu, Xixi, Walling, Desmond E., Zhang, Ting, Steiner, Jakob F., Wasson, Robert J., Harrison, Stephan, Nepal, Santosh, Nie, Yong, Immerzeel, Walter W., Shugar, Dan H., Koppes, Michèle, Lane, Stuart, Zeng, Zhenzhong, Sun, Xiaofei, Yegorov, Alexandr, and Bolch, Tobias

Published
2022

33. Output of model simulations used for publication 'South Asian agriculture increasingly dependent on meltwater and groundwater'

Author

Lutz, Arthur F., Immerzeel, Walter W., Siderius, Christian, Wijngaard, René R., Nepal, Santosh, Shrestha, Arun B., Wester, Philippus, Biemans, Hester, Lutz, Arthur F., Immerzeel, Walter W., Siderius, Christian, Wijngaard, René R., Nepal, Santosh, Shrestha, Arun B., Wester, Philippus, and Biemans, Hester

Abstract

Output of model simulations used for publication "South Asian agriculture increasingly dependent on meltwater and groundwater", published in Nature Climate Change in 2022. The archive contains outputs of 8 model runs forced with different combinations of GCMs and SSPs. All outputs are stored in NetCDF files at 5 minute spatial resolution covering the downstream spatial model domain (Indus, Ganges and Brahmaputra river basins), and cover the period 1981-2100.

Published
2022

38. Distributed Melt on a Debris-Covered Glacier: Field Observations and Melt Modeling on the Lirung Glacier in the Himalaya

Author

Steiner, Jakob F., Kraaijenbrink, Philip D.A., Immerzeel, Walter W., Landscape functioning, Geocomputation and Hydrology, Hydrologie, Landscape functioning, Geocomputation and Hydrology, and Hydrologie

Subjects
temperature index, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Scale (ratio), Science, Himalaya, Energy balance, Elevation, Earth and Planetary Sciences(all), Glacier, debris cover, Forcing (mathematics), 010502 geochemistry & geophysics, Monsoon, 01 natural sciences, Debris, energy balance, Thermal conductivity, General Earth and Planetary Sciences, glacier melt, Geomorphology, Geology, 0105 earth and related environmental sciences
Abstract

Debris-covered glaciers, especially in high-mountain Asia, have received increased attention in recent years. So far, few field-based observations of distributed mass loss exist and both the properties of the debris layer as well as the atmospheric drivers of melt below debris remain poorly understood. Using multi-year observations of on-glacier atmospheric data, debris properties and spatial surface elevation changes from repeat flights with an unmanned aerial vehicle (UAV), we quantify the necessary variables to compute melt for the Lirung Glacier in the Himalaya. By applying an energy balance model we reproduce observed mass loss during one monsoon season in 2013. We show that melt is especially sensitive to thermal conductivity and thickness of debris. Our observations show that previously used values in literature for the thermal conductivity through debris are valid but variability in space on a single glacier remains high. We also present a simple melt model, which is calibrated based on the results of energy balance model, that is only dependent on air temperature and debris thickness and is therefore applicable for larger scale studies. This simple melt model reproduces melt under thin debris (

Published
2021

42. The impact of meteorological and hydrological memory on compound peak flows in the Rhine river basin

Author

Khanal, Sonu, Lutz, Arthur F., Immerzeel, Walter W., de Vries, Hylke, Wanders, Niko, van den Hurk, Bart, Hydrologie, Landdegradatie en aardobservatie, Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, Hydrologie, Landdegradatie en aardobservatie, Sub Dynamics Meteorology, Landscape functioning, Geocomputation and Hydrology, and Water and Climate Risk

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, 0208 environmental biotechnology, Drainage basin, 02 engineering and technology, lcsh:QC851-999, Environmental Science (miscellaneous), Atmospheric sciences, 01 natural sciences, Memory, Compound events, Precipitation, Auto correlation, Meltwater, Temporal scales, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Flood myth, Snow, SDG 11 - Sustainable Cities and Communities, 020801 environmental engineering, 13. Climate action, Environmental science, lcsh:Meteorology. Climatology, Climate model, Surface runoff
Abstract

Spatio-temporal variation of hydrological processes that have a strong lagged autocorrelation (memory), such as soil moisture, snow accumulation and the antecedent hydro-climatic conditions, significantly impact the peaks of flood waves. Ignoring these memory processes leads to biased estimates of floods and high river levels that are sensitive to the occurrence of these compounding hydro-meteorological processes. Here, we investigate the role of memory in hydrological and meteorological systems at different temporal scales for the Rhine basin. We simulate the hydrological regime of the Rhine river basin using a distributed hydrological model (SPHY) forced with 1950&ndash, 2000 atmospheric conditions from an ensemble simulation with a high resolution (0.11&deg, /12 km) regional climate model (RACMO2). The findings show that meltwater from antecedent anomalous snowfall results in a time shift of the discharge peak. Soil moisture modulates the rainfall-runoff relationship and generates a strong runoff response at high soil moisture levels and buffers the generation of runoff peaks at low levels. Additionally, our results show that meteorological autocorrelation (manifesting itself by the occurrence of clustered precipitation events) has a strong impact on the magnitude of peak discharge. Removing meteorological autocorrelation at time scales longer than five days reduces peak discharge by 80% relative to the reference climate. At time scales longer than 30 days this meteorological autocorrelation loses its significant role in generating high discharge levels.

Published
2019

45. Distributed Melt on a Debris-Covered Glacier: Field Observations and Melt Modeling on the Lirung Glacier in the Himalaya

Author

Landscape functioning, Geocomputation and Hydrology, Hydrologie, Steiner, Jakob F.|info:eu-repo/dai/nl/119338653, Kraaijenbrink, Philip D.A., Immerzeel, Walter W.|info:eu-repo/dai/nl/290472113, Landscape functioning, Geocomputation and Hydrology, Hydrologie, Steiner, Jakob F.|info:eu-repo/dai/nl/119338653, Kraaijenbrink, Philip D.A., and Immerzeel, Walter W.|info:eu-repo/dai/nl/290472113

Published
2021

46. Climate change decisive for Asia’s snow meltwater supply

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Kraaijenbrink, Philip D.A., Stigter, Emmy E., Yao, Tandong, Immerzeel, Walter W., Hydrologie, Landscape functioning, Geocomputation and Hydrology, Kraaijenbrink, Philip D.A., Stigter, Emmy E., Yao, Tandong, and Immerzeel, Walter W.

Published
2021

47. Multi‐year observations of the high mountain water cycle in the Langtang catchment, Central Himalaya

Author

Landscape functioning, Geocomputation and Hydrology, Hydrologie, Steiner, Jakob F., Gurung, Tika R., Joshi, Sharad P., Koch, Inka, Saloranta, Tuomo, Shea, Joseph, Shrestha, Arun B., Stigter, Emmy, Immerzeel, Walter W., Landscape functioning, Geocomputation and Hydrology, Hydrologie, Steiner, Jakob F., Gurung, Tika R., Joshi, Sharad P., Koch, Inka, Saloranta, Tuomo, Shea, Joseph, Shrestha, Arun B., Stigter, Emmy, and Immerzeel, Walter W.

Published
2021

48. A systematic framework for the assessment of sustainable hydropower potential in a river basin – The case of the upper Indus

Author

Hydrologie, Environmental Sciences, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Gernaat, David E.H.J., Nepal, Santosh, Smolenaars, Wouter, Pradhananga, Saurav, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun B., Immerzeel, Walter W., Hydrologie, Environmental Sciences, Landscape functioning, Geocomputation and Hydrology, Dhaubanjar, Sanita, Lutz, Arthur F., Gernaat, David E.H.J., Nepal, Santosh, Smolenaars, Wouter, Pradhananga, Saurav, Biemans, Hester, Ludwig, Fulco, Shrestha, Arun B., and Immerzeel, Walter W.

Published
2021

49. From narratives to numbers: Spatial downscaling and quantification of future water, food & energy security requirements in the Indus basin

Author

Hydrologie, Landscape functioning, Geocomputation and Hydrology, Smolenaars, Wouter J., Lutz, Arthur F., Biemans, Hester, Dhaubanjar, Sanita, Immerzeel, Walter W., Ludwig, Fulco, Hydrologie, Landscape functioning, Geocomputation and Hydrology, Smolenaars, Wouter J., Lutz, Arthur F., Biemans, Hester, Dhaubanjar, Sanita, Immerzeel, Walter W., and Ludwig, Fulco

Published
2021

50. Mapping the aerodynamic roughness of the Greenland Ice Sheet surface using ICESat-2: Evaluation over the K-transect

Author

van Tiggelen, Maurice (author), Smeets, Paul C. J. P. (author), Reijmer, Carleen H. (author), Wouters, B. (author), Steiner, Jakob F. (author), Nieuwstraten, Emile J. (author), Immerzeel, Walter W. (author), van den Broeke, Michiel R. (author), van Tiggelen, Maurice (author), Smeets, Paul C. J. P. (author), Reijmer, Carleen H. (author), Wouters, B. (author), Steiner, Jakob F. (author), Nieuwstraten, Emile J. (author), Immerzeel, Walter W. (author), and van den Broeke, Michiel R. (author)

Abstract

The aerodynamic roughness of heat, moisture, and momentum of a natural surface are important parameters in atmospheric models, as they co-determine the intensity of turbulent transfer between the atmosphere and the surface. Unfortunately this parameter is often poorly known, especially in remote areas where neither high-resolution elevation models nor eddy-covariance measurements are available. In this study we adapt a bulk drag partitioning model to estimate the aerodynamic roughness length (z0m) such that it can be applied to 1D (i.e. unidirectional) elevation profiles, typically measured by laser altimeters. We apply the model to a rough ice surface on the K-transect (west Greenland Ice Sheet) using UAV photogrammetry, and we evaluate the modelled roughness against in situ eddy-covariance observations. We then present a method to estimate the topography at 1 m horizontal resolution using the ICESat-2 satellite laser altimeter, and we demonstrate the high precision of the satellite elevation profiles against UAV photogrammetry. The currently available satellite profiles are used to map the aerodynamic roughness during different time periods along the K-transect, that is compared to an extensive dataset of in situ observations. We find a considerable spatiooral variability in z0m, ranging between 10-4 m for a smooth snow surface and 10-1 m for rough crevassed areas, which confirms the need to incorporate a variable aerodynamic roughness in atmospheric models over ice sheets., Physical and Space Geodesy

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results