Articles | Volume 25, issue 8
https://doi.org/10.5194/hess-25-4455-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/hess-25-4455-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Aug 2021
Research article |
| 19 Aug 2021
| 19 Aug 2021
Snowpack dynamics in the Lebanese mountains from quasi-dynamically downscaled ERA5 reanalysis updated by assimilating remotely sensed fractional snow-covered area
Esteban Alonso-González
CORRESPONDING AUTHOR
Instituto Pirenaico de Ecología, Spanish Research Council
(IPE-CSIC), Zaragoza, Spain
Ethan Gutmann
Research Application Laboratory, National Center for Atmospheric Research (RAL-NCAR), Boulder, CO, USA
Kristoffer Aalstad
Department of Geosciences, University of Oslo, Oslo, Norway
Abbas Fayad
Centre for Hydrology, University of Saskatchewan, Saskatoon,
Saskatchewan, Canada
Marine Bouchet
Centre d'Etudes Spatiales de la Biosphère (CESBIO),
UPS/CNRS/IRD/INRA/CNES, Toulouse, France
Simon Gascoin
Centre d'Etudes Spatiales de la Biosphère (CESBIO),
UPS/CNRS/IRD/INRA/CNES, Toulouse, France
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Sara Arioli, Ghislain Picard, Laurent Arnaud, Simon Gascoin, Esteban Alonso-González, Marine Poizat, and Mark Irvine
Earth Syst. Sci. Data, 16, 3913–3934, https://doi.org/10.5194/essd-16-3913-2024, https://doi.org/10.5194/essd-16-3913-2024, 2024
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Lahoucine Hanich, Ouiaam Lahnik, Simon Gascoin, Adnane Chakir, and Vincent Simonneaux
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Dylan Reynolds, Ethan Gutmann, Bert Kruyt, Michael Haugeneder, Tobias Jonas, Franziska Gerber, Michael Lehning, and Rebecca Mott
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Esteban Alonso-González, Simon Gascoin, Sara Arioli, and Ghislain Picard
The Cryosphere, 17, 3329–3342, https://doi.org/10.5194/tc-17-3329-2023, https://doi.org/10.5194/tc-17-3329-2023, 2023
Short summary
Short summary
Data assimilation techniques are a promising approach to improve snowpack simulations in remote areas that are difficult to monitor. This paper studies the ability of satellite-observed land surface temperature to improve snowpack simulations through data assimilation. We show that it is possible to improve snowpack simulations, but the temporal resolution of the observations and the algorithm used are critical to obtain satisfactory results.
Ixeia Vidaller, Eñaut Izagirre, Luis Mariano del Rio, Esteban Alonso-González, Francisco Rojas-Heredia, Enrique Serrano, Ana Moreno, Juan Ignacio López-Moreno, and Jesús Revuelto
The Cryosphere, 17, 3177–3192, https://doi.org/10.5194/tc-17-3177-2023, https://doi.org/10.5194/tc-17-3177-2023, 2023
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The Aneto glacier, the largest glacier in the Pyrenees, has shown continuous surface and ice thickness losses in the last decades. In this study, we examine changes in its surface and ice thickness for 1981–2022 and the remaining ice thickness in 2020. During these 41 years, the glacier has shrunk by 64.7 %, and the ice thickness has decreased by 30.5 m on average. The mean ice thickness in 2022 was 11.9 m, compared to 32.9 m in 1981. The results highlight the critical situation of the glacier.
Marie Dumont, Simon Gascoin, Marion Réveillet, Didier Voisin, François Tuzet, Laurent Arnaud, Mylène Bonnefoy, Montse Bacardit Peñarroya, Carlo Carmagnola, Alexandre Deguine, Aurélie Diacre, Lukas Dürr, Olivier Evrard, Firmin Fontaine, Amaury Frankl, Mathieu Fructus, Laure Gandois, Isabelle Gouttevin, Abdelfateh Gherab, Pascal Hagenmuller, Sophia Hansson, Hervé Herbin, Béatrice Josse, Bruno Jourdain, Irene Lefevre, Gaël Le Roux, Quentin Libois, Lucie Liger, Samuel Morin, Denis Petitprez, Alvaro Robledano, Martin Schneebeli, Pascal Salze, Delphine Six, Emmanuel Thibert, Jürg Trachsel, Matthieu Vernay, Léo Viallon-Galinier, and Céline Voiron
Earth Syst. Sci. Data, 15, 3075–3094, https://doi.org/10.5194/essd-15-3075-2023, https://doi.org/10.5194/essd-15-3075-2023, 2023
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Saharan dust outbreaks have profound effects on ecosystems, climate, health, and the cryosphere, but the spatial deposition pattern of Saharan dust is poorly known. Following the extreme dust deposition event of February 2021 across Europe, a citizen science campaign was launched to sample dust on snow over the Pyrenees and the European Alps. This campaign triggered wide interest and over 100 samples. The samples revealed the high variability of the dust properties within a single event.
César Deschamps-Berger, Simon Gascoin, David Shean, Hannah Besso, Ambroise Guiot, and Juan Ignacio López-Moreno
The Cryosphere, 17, 2779–2792, https://doi.org/10.5194/tc-17-2779-2023, https://doi.org/10.5194/tc-17-2779-2023, 2023
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The estimation of the snow depth in mountains is hard, despite the importance of the snowpack for human societies and ecosystems. We measured the snow depth in mountains by comparing the elevation of points measured with snow from the high-precision altimetric satellite ICESat-2 to the elevation without snow from various sources. Snow depths derived only from ICESat-2 were too sparse, but using external airborne/satellite products results in spatially richer and sufficiently precise snow depths.
Norbert Pirk, Kristoffer Aalstad, Yeliz A. Yilmaz, Astrid Vatne, Andrea L. Popp, Peter Horvath, Anders Bryn, Ane Victoria Vollsnes, Sebastian Westermann, Terje Koren Berntsen, Frode Stordal, and Lena Merete Tallaksen
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We measured the land–atmosphere exchange of CO2 and water vapor in alpine Norway over 3 years. The extremely snow-rich conditions in 2020 reduced the total annual evapotranspiration to 50 % and reduced the growing-season carbon assimilation to turn the ecosystem from a moderate annual carbon sink to an even stronger source. Our analysis suggests that snow cover anomalies are driving the most consequential short-term responses in this ecosystem’s functioning.
Sebastian Westermann, Thomas Ingeman-Nielsen, Johanna Scheer, Kristoffer Aalstad, Juditha Aga, Nitin Chaudhary, Bernd Etzelmüller, Simon Filhol, Andreas Kääb, Cas Renette, Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Robin B. Zweigel, Léo Martin, Sarah Morard, Matan Ben-Asher, Michael Angelopoulos, Julia Boike, Brian Groenke, Frederieke Miesner, Jan Nitzbon, Paul Overduin, Simone M. Stuenzi, and Moritz Langer
Geosci. Model Dev., 16, 2607–2647, https://doi.org/10.5194/gmd-16-2607-2023, https://doi.org/10.5194/gmd-16-2607-2023, 2023
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The CryoGrid community model is a new tool for simulating ground temperatures and the water and ice balance in cold regions. It is a modular design, which makes it possible to test different schemes to simulate, for example, permafrost ground in an efficient way. The model contains tools to simulate frozen and unfrozen ground, snow, glaciers, and other massive ice bodies, as well as water bodies.
Arthur Bayle, Bradley Z. Carlson, Anaïs Zimmer, Sophie Vallée, Antoine Rabatel, Edoardo Cremonese, Gianluca Filippa, Cédric Dentant, Christophe Randin, Andrea Mainetti, Erwan Roussel, Simon Gascoin, Dov Corenblit, and Philippe Choler
Biogeosciences, 20, 1649–1669, https://doi.org/10.5194/bg-20-1649-2023, https://doi.org/10.5194/bg-20-1649-2023, 2023
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Glacier forefields have long provided ecologists with a model to study patterns of plant succession following glacier retreat. We used remote sensing approaches to study early succession dynamics as it allows to analyze the deglaciation, colonization, and vegetation growth within a single framework. We found that the heterogeneity of early succession dynamics is deterministic and can be explained well by local environmental context. This work has been done by an international consortium.
Josep Bonsoms, Juan Ignacio López-Moreno, and Esteban Alonso-González
The Cryosphere, 17, 1307–1326, https://doi.org/10.5194/tc-17-1307-2023, https://doi.org/10.5194/tc-17-1307-2023, 2023
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This work analyzes the snow response to temperature and precipitation in the Pyrenees. During warm and wet seasons, seasonal snow depth is expected to be reduced by −37 %, −34 %, and −27 % per degree Celsius at low-, mid-, and high-elevation areas, respectively. The largest snow reductions are anticipated at low elevations of the eastern Pyrenees. Results anticipate important impacts on the nearby ecological and socioeconomic systems.
Cas Renette, Kristoffer Aalstad, Juditha Aga, Robin Benjamin Zweigel, Bernd Etzelmüller, Karianne Staalesen Lilleøren, Ketil Isaksen, and Sebastian Westermann
Earth Surf. Dynam., 11, 33–50, https://doi.org/10.5194/esurf-11-33-2023, https://doi.org/10.5194/esurf-11-33-2023, 2023
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One of the reasons for lower ground temperatures in coarse, blocky terrain is a low or varying soil moisture content, which most permafrost modelling studies did not take into account. We used the CryoGrid community model to successfully simulate this effect and found markedly lower temperatures in well-drained, blocky deposits compared to other set-ups. The inclusion of this drainage effect is another step towards a better model representation of blocky mountain terrain in permafrost regions.
Esteban Alonso-González, Kristoffer Aalstad, Mohamed Wassim Baba, Jesús Revuelto, Juan Ignacio López-Moreno, Joel Fiddes, Richard Essery, and Simon Gascoin
Geosci. Model Dev., 15, 9127–9155, https://doi.org/10.5194/gmd-15-9127-2022, https://doi.org/10.5194/gmd-15-9127-2022, 2022
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Snow cover plays an important role in many processes, but its monitoring is a challenging task. The alternative is usually to simulate the snowpack, and to improve these simulations one of the most promising options is to fuse simulations with available observations (data assimilation). In this paper we present MuSA, a data assimilation tool which facilitates the implementation of snow monitoring initiatives, allowing the assimilation of a wide variety of remotely sensed snow cover information.
Norbert Pirk, Kristoffer Aalstad, Sebastian Westermann, Astrid Vatne, Alouette van Hove, Lena Merete Tallaksen, Massimo Cassiani, and Gabriel Katul
Atmos. Meas. Tech., 15, 7293–7314, https://doi.org/10.5194/amt-15-7293-2022, https://doi.org/10.5194/amt-15-7293-2022, 2022
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In this study, we show how sparse and noisy drone measurements can be combined with an ensemble of turbulence-resolving wind simulations to estimate uncertainty-aware surface energy exchange. We demonstrate the feasibility of this drone data assimilation framework in a series of synthetic and real-world experiments. This new framework can, in future, be applied to estimate energy and gas exchange in heterogeneous landscapes more representatively than conventional methods.
Maximillian Van Wyk de Vries, Shashank Bhushan, Mylène Jacquemart, César Deschamps-Berger, Etienne Berthier, Simon Gascoin, David E. Shean, Dan H. Shugar, and Andreas Kääb
Nat. Hazards Earth Syst. Sci., 22, 3309–3327, https://doi.org/10.5194/nhess-22-3309-2022, https://doi.org/10.5194/nhess-22-3309-2022, 2022
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On 7 February 2021, a large rock–ice avalanche occurred in Chamoli, Indian Himalaya. The resulting debris flow swept down the nearby valley, leaving over 200 people dead or missing. We use a range of satellite datasets to investigate how the collapse area changed prior to collapse. We show that signs of instability were visible as early 5 years prior to collapse. However, it would likely not have been possible to predict the timing of the event from current satellite datasets.
Joel Fiddes, Kristoffer Aalstad, and Michael Lehning
Geosci. Model Dev., 15, 1753–1768, https://doi.org/10.5194/gmd-15-1753-2022, https://doi.org/10.5194/gmd-15-1753-2022, 2022
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This study describes and evaluates a new downscaling scheme that addresses the need for hillslope-scale atmospheric forcing time series for modelling the local impact of regional climate change on the land surface in mountain areas. The method has a global scope and is able to generate all model forcing variables required for hydrological and land surface modelling. This is important, as impact models require high-resolution forcings such as those generated here to produce meaningful results.
Zacharie Barrou Dumont, Simon Gascoin, Olivier Hagolle, Michaël Ablain, Rémi Jugier, Germain Salgues, Florence Marti, Aurore Dupuis, Marie Dumont, and Samuel Morin
The Cryosphere, 15, 4975–4980, https://doi.org/10.5194/tc-15-4975-2021, https://doi.org/10.5194/tc-15-4975-2021, 2021
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Since 2020, the Copernicus High Resolution Snow & Ice Monitoring Service has distributed snow cover maps at 20 m resolution over Europe in near-real time. These products are derived from the Sentinel-2 Earth observation mission, with a revisit time of 5 d or less (cloud-permitting). Here we show the good accuracy of the snow detection over a wide range of regions in Europe, except in dense forest regions where the snow cover is hidden by the trees.
Nora Helbig, Michael Schirmer, Jan Magnusson, Flavia Mäder, Alec van Herwijnen, Louis Quéno, Yves Bühler, Jeff S. Deems, and Simon Gascoin
The Cryosphere, 15, 4607–4624, https://doi.org/10.5194/tc-15-4607-2021, https://doi.org/10.5194/tc-15-4607-2021, 2021
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The snow cover spatial variability in mountains changes considerably over the course of a snow season. In applications such as weather, climate and hydrological predictions the fractional snow-covered area is therefore an essential parameter characterizing how much of the ground surface in a grid cell is currently covered by snow. We present a seasonal algorithm and a spatiotemporal evaluation suggesting that the algorithm can be applied in other geographic regions by any snow model application.
Esteban Alonso-González and Víctor Fernández-García
Earth Syst. Sci. Data, 13, 1925–1938, https://doi.org/10.5194/essd-13-1925-2021, https://doi.org/10.5194/essd-13-1925-2021, 2021
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We present the first global burn severity database (MOSEV database), which is based on Moderate Resolution Imaging Spectroradiometer (MODIS) surface reflectance and burned area products. The database inludes monthly scenes with the dNBR, RdNBR and post-burn NBR spectral indices at 500 m spatial resolution from November 2000 onwards. Moreover, in this work we show that there is a close relationship between the burn severity metrics included in MOSEV and the same ones obtained from Landsat-8.
Andreas Kääb, Mylène Jacquemart, Adrien Gilbert, Silvan Leinss, Luc Girod, Christian Huggel, Daniel Falaschi, Felipe Ugalde, Dmitry Petrakov, Sergey Chernomorets, Mikhail Dokukin, Frank Paul, Simon Gascoin, Etienne Berthier, and Jeffrey S. Kargel
The Cryosphere, 15, 1751–1785, https://doi.org/10.5194/tc-15-1751-2021, https://doi.org/10.5194/tc-15-1751-2021, 2021
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Hardly recognized so far, giant catastrophic detachments of glaciers are a rare but great potential for loss of lives and massive damage in mountain regions. Several of the events compiled in our study involve volumes (up to 100 million m3 and more), avalanche speeds (up to 300 km/h), and reaches (tens of kilometres) that are hard to imagine. We show that current climate change is able to enhance associated hazards. For the first time, we elaborate a set of factors that could cause these events.
Johannes Horak, Marlis Hofer, Ethan Gutmann, Alexander Gohm, and Mathias W. Rotach
Geosci. Model Dev., 14, 1657–1680, https://doi.org/10.5194/gmd-14-1657-2021, https://doi.org/10.5194/gmd-14-1657-2021, 2021
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This process-based evaluation of the atmospheric model ICAR is conducted to derive recommendations to increase the likelihood of its results being correct for the right reasons. We conclude that a different diagnosis of the atmospheric background state is necessary, as well as a model top at an elevation of at least 10 km. Alternative boundary conditions at the top were not found to be effective in reducing this model top elevation. The results have wide implications for future ICAR studies.
Ana Moreno, Miguel Bartolomé, Juan Ignacio López-Moreno, Jorge Pey, Juan Pablo Corella, Jordi García-Orellana, Carlos Sancho, María Leunda, Graciela Gil-Romera, Penélope González-Sampériz, Carlos Pérez-Mejías, Francisco Navarro, Jaime Otero-García, Javier Lapazaran, Esteban Alonso-González, Cristina Cid, Jerónimo López-Martínez, Belén Oliva-Urcia, Sérgio Henrique Faria, María José Sierra, Rocío Millán, Xavier Querol, Andrés Alastuey, and José M. García-Ruíz
The Cryosphere, 15, 1157–1172, https://doi.org/10.5194/tc-15-1157-2021, https://doi.org/10.5194/tc-15-1157-2021, 2021
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Our study of the chronological sequence of Monte Perdido Glacier in the Central Pyrenees (Spain) reveals that, although the intense warming associated with the Roman period or Medieval Climate Anomaly produced important ice mass losses, it was insufficient to make this glacier disappear. By contrast, recent global warming has melted away almost 600 years of ice accumulated since the Little Ice Age, jeopardising the survival of this and other southern European glaciers over the next few decades.
Vincent Vionnet, Christopher B. Marsh, Brian Menounos, Simon Gascoin, Nicholas E. Wayand, Joseph Shea, Kriti Mukherjee, and John W. Pomeroy
The Cryosphere, 15, 743–769, https://doi.org/10.5194/tc-15-743-2021, https://doi.org/10.5194/tc-15-743-2021, 2021
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Mountain snow cover provides critical supplies of fresh water to downstream users. Its accurate prediction requires inclusion of often-ignored processes. A multi-scale modelling strategy is presented that efficiently accounts for snow redistribution. Model accuracy is assessed via airborne lidar and optical satellite imagery. With redistribution the model captures the elevation–snow depth relation. Redistribution processes are required to reproduce spatial variability, such as around ridges.
Rhae Sung Kim, Sujay Kumar, Carrie Vuyovich, Paul Houser, Jessica Lundquist, Lawrence Mudryk, Michael Durand, Ana Barros, Edward J. Kim, Barton A. Forman, Ethan D. Gutmann, Melissa L. Wrzesien, Camille Garnaud, Melody Sandells, Hans-Peter Marshall, Nicoleta Cristea, Justin M. Pflug, Jeremy Johnston, Yueqian Cao, David Mocko, and Shugong Wang
The Cryosphere, 15, 771–791, https://doi.org/10.5194/tc-15-771-2021, https://doi.org/10.5194/tc-15-771-2021, 2021
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High SWE uncertainty is observed in mountainous and forested regions, highlighting the need for high-resolution snow observations in these regions. Substantial uncertainty in snow water storage in Tundra regions and the dominance of water storage in these regions points to the need for high-accuracy snow estimation. Finally, snow measurements during the melt season are most needed at high latitudes, whereas observations at near peak snow accumulations are most beneficial over the midlatitudes.
Nora Helbig, Yves Bühler, Lucie Eberhard, César Deschamps-Berger, Simon Gascoin, Marie Dumont, Jesus Revuelto, Jeff S. Deems, and Tobias Jonas
The Cryosphere, 15, 615–632, https://doi.org/10.5194/tc-15-615-2021, https://doi.org/10.5194/tc-15-615-2021, 2021
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The spatial variability in snow depth in mountains is driven by interactions between topography, wind, precipitation and radiation. In applications such as weather, climate and hydrological predictions, this is accounted for by the fractional snow-covered area describing the fraction of the ground surface covered by snow. We developed a new description for model grid cell sizes larger than 200 m. An evaluation suggests that the description performs similarly well in most geographical regions.
El Mahdi El Khalki, Yves Tramblay, Christian Massari, Luca Brocca, Vincent Simonneaux, Simon Gascoin, and Mohamed El Mehdi Saidi
Nat. Hazards Earth Syst. Sci., 20, 2591–2607, https://doi.org/10.5194/nhess-20-2591-2020, https://doi.org/10.5194/nhess-20-2591-2020, 2020
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In North Africa, the vulnerability to floods is high, and there is a need to improve the flood-forecasting systems. Remote-sensing and reanalysis data can palliate the lack of in situ measurements, in particular for soil moisture, which is a crucial parameter to consider when modeling floods. In this study we provide an evaluation of recent globally available soil moisture products for flood modeling in Morocco.
César Deschamps-Berger, Simon Gascoin, Etienne Berthier, Jeffrey Deems, Ethan Gutmann, Amaury Dehecq, David Shean, and Marie Dumont
The Cryosphere, 14, 2925–2940, https://doi.org/10.5194/tc-14-2925-2020, https://doi.org/10.5194/tc-14-2925-2020, 2020
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We evaluate a recent method to map snow depth based on satellite photogrammetry. We compare it with accurate airborne laser-scanning measurements in the Sierra Nevada, USA. We find that satellite data capture the relationship between snow depth and elevation at the catchment scale and also small-scale features like snow drifts and avalanche deposits. We conclude that satellite photogrammetry stands out as a convenient method to estimate the spatial distribution of snow depth in high mountains.
Cited articles
Aalstad, K., Westermann, S., Schuler, T. V., Boike, J., and Bertino, L.: Ensemble-based assimilation of fractional snow-covered area satellite retrievals to estimate the snow distribution at Arctic sites, The Cryosphere, 12, 247–270, https://doi.org/10.5194/tc-12-247-2018, 2018.
Aalstad, K., Westermann, S., and Bertino, L.: Evaluating satellite retrieved
fractional snow-covered area at a high-Arctic site using terrestrial
photography, Remote Sens. Environ, 239, 111618,
https://doi.org/10.1016/j.rse.2019.111618, 2020.
Albergel, C., Dutra, E., Munier, S., Calvet, J.-C., Munoz-Sabater, J., de Rosnay, P., and Balsamo, G.: ERA-5 and ERA-Interim driven ISBA land surface model simulations: which one performs better?, Hydrol. Earth Syst. Sci., 22, 3515–3532, https://doi.org/10.5194/hess-22-3515-2018, 2018.
Alonso-González, E., López-Moreno, J. I., Gascoin, S., García-Valdecasas Ojeda, M., Sanmiguel-Vallelado, A., Navarro-Serrano, F., Revuelto, J., Ceballos, A., Esteban-Parra, M. J., and Essery, R.: Daily gridded datasets of snow depth and snow water equivalent for the Iberian Peninsula from 1980 to 2014, Earth Syst. Sci. Data, 10, 303–315, https://doi.org/10.5194/essd-10-303-2018, 2018.
Alonso-González, E., López-Moreno, J. I., Navarro-Serrano, F.,
Sanmiguel-Vallelado, A., Aznárez-Balta, M., Revuelto, J., and Ceballos, A.: Snowpack sensitivity to temperature, precipitation, and solar
radiation variability over an elevational gradient in the Iberian mountains, Atmos. Res., 243, 104973, https://doi.org/10.1016/j.atmosres.2020.104973, 2020a.
Alonso-González, E., López-Moreno, J. I., Navarro-Serrano, F.,
Sanmiguel-Vallelado, A., Revuelto, J., Domínguez-Castro, F., and Ceballos,
A.: Snow climatology for the mountains in the Iberian Peninsula using
satellite imagery and simulations with dynamically downscaled reanalysis
data, Int. J. Climatol., 40, 477–491, https://doi.org/10.1002/joc.6223,
2020b.
Arasa, R., Porras, I., Domingo-Dalmau, A., Picanyol, M., Codina, B.,
González, M. Á., and Piñón, J.: Defining a Standard
Methodology to Obtain Optimum WRF Configuration for Operational Forecast:
Application over the Port of Huelva (Southern Spain), Atmos. Clim. Sci., 6,
329–350, https://doi.org/10.4236/acs.2016.62028, 2016.
Baba, M. W., Gascoin, S., and Hanich, L.: Assimilation of Sentinel-2 data into a
snowpack model in the High Atlas of Morocco, Remote Sens., 10, 1982,
https://doi.org/10.3390/rs10121982, 2018a.
Baba, M. W., Gascoin, S., Jarlan, L., Simonneaux, V., and Hanich, L.: Variations
of the snow water equivalent in the ourika catchment (Morocco) over
2000–2018 using downscaled MERRA-2 data, Water, 10, 1120,
https://doi.org/10.3390/w10091120, 2018b.
Baba, M. W., Gascoin, S., Kinnard, C., Marchane, A., and Hanich, L.: Effect of
Digital Elevation Model Resolution on the Simulation of the Snow Cover
Evolution in the High Atlas, Water Resour. Res., 55, 5360–5378,
https://doi.org/10.1029/2018WR023789, 2019.
Bakalowicz, M., El Hakim, M., and El-Hajj, A.: Karst groundwater resources in
the countries of eastern Mediterranean: The example of Lebanon, Environ.
Geol., 54, 597–604, https://doi.org/10.1007/s00254-007-0854-z, 2008.
Barlage, M., Chen, F., Tewari, M., Ikeda, K., Gochis, D., Dudhia, J.,
Rasmussen, R., Livneh, B., Ek, M., and Mitchell, K.: Noah land surface model
modifications to improve snowpack prediction in the Colorado Rocky
Mountains, J. Geophys. Res.-Atmos., 115,
https://doi.org/10.1029/2009JD013470, 2010.
Betts, A. K. and Miller, M. J.: A new convective adjustment scheme. Part II:
Single column tests using GATE wave, BOMEX, ATEX and arctic air-mass data
sets, Q. J. Roy. Meteor. Soc., 112, 693–709,
https://doi.org/10.1002/qj.49711247308, 1986.
Bormann, K. J., Westra, S., Evans, J. P., and McCabe, M. F.: Spatial and temporal
variability in seasonal snow density, J. Hydrol., 484, 63–73,
https://doi.org/10.1016/j.jhydrol.2013.01.032, 2013.
Chen, F. and Dudhia, J.: Coupling an advanced land surface-hydrology model with
the Penn-State-NCAR MM5 modeling system. Part II: Preliminary model
validation, Mon. Weather Rev., 129, 587–604,
https://doi.org/10.1175/1520-0493(2001)129<0587:CAALSH>2.0.CO;2, 2001.
Cluzet, B., Lafaysse, M., Cosme, E., Albergel, C., Meunier, L.-F., and Dumont, M.: CrocO_v1.0: a particle filter to assimilate snowpack observations in a spatialised framework, Geosci. Model Dev., 14, 1595–1614, https://doi.org/10.5194/gmd-14-1595-2021, 2021.
Cook, B. I., Anchukaitis, K. J., Touchan, R., Meko, D. M., and Cook, E. R.:
Spatiotemporal drought variability in the mediterranean over the last 900
years, J. Geophys. Res., 121, 2060–2074,
https://doi.org/10.1002/2015JD023929, 2016.
Cortés, G., Girotto, M., and Margulis, S.: Snow process estimation over the
extratropical Andes using a data assimilation framework integrating MERRA
data and Landsat imagery, Water Resour. Res., 52, 2582–2600,
https://doi.org/10.1002/2015WR018376, 2016.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B., Hersbach, H., Hólm, E. V., Isaksen, L., Kållberg, P., Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, J.-N., and Vitart, F.: The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. Roy. Meteor. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Dawson, N., Broxton, P., and Zeng, X.: A new snow density parameterization for
land data initialization, J. Hydrometeorol., 18, 197–207,
https://doi.org/10.1175/JHM-D-16-0166.1, 2017.
El-Fadel, M., Zeinati, M., and Jamali, D.: Water resources in Lebanon:
Characterization, water balance and constraints, Int. J. Water Resour. Dev.,
16, 615–638, https://doi.org/10.1080/713672540, 2000.
Essery, R.: A factorial snowpack model (FSM 1.0), Geosci. Model Dev., 8, 3867–3876, https://doi.org/10.5194/gmd-8-3867-2015, 2015a.
Essery, R.: Flexible Snow Model – a multi-physics energy balance model of accumulation and melt of snow on the ground and in forest canopies, available at: https://github.com/RichardEssery/FSM2 (last access: 14 July 2021), 2015b.
Farajalla, N. and Ziade, R.: Drought frequency under a changing climate in the Eastern Mediterranean: the Beka'a Valley, Lebanon, in: EGU General Assembly Conference Abstracts, p. 11653, available at: https://ui.adsabs.harvard.edu/abs/2010EGUGA..1211653F/abstract (last access: 14 July 2021), 2010.
Fayad, A. and Gascoin, S.: The role of liquid water percolation representation in estimating snow water equivalent in a Mediterranean mountain region (Mount Lebanon), Hydrol. Earth Syst. Sci., 24, 1527–1542, https://doi.org/10.5194/hess-24-1527-2020, 2020.
Fayad, A., Gascoin, S., Faour, G., Fanise, P., Drapeau, L., Somma, J., Fadel, A., Al Bitar, A., and Escadafal, R.: Snow observations in Mount Lebanon (2011–2016), Earth Syst. Sci. Data, 9, 573–587, https://doi.org/10.5194/essd-9-573-2017, 2017a.
Fayad, A., Gascoin, S., Faour, G., López-Moreno, J. I., Drapeau, L.,
Page, M. L., and Escadafal, R.: Snow hydrology in Mediterranean mountain
regions: A review, J. Hydrol. 551, 374–396,
https://doi.org/10.1016/j.jhydrol.2017.05.063, 2017b.
Fayad, A., Gascoin, S., Faour, G., Fanise, P., and Drapeau, L.: Snow dataset for Mount-Lebanon (2011–2016), https://doi.org/10.5281/zenodo.583733, 2017.
Fiddes, J. and Gruber, S.: TopoSCALE v.1.0: downscaling gridded climate data in complex terrain, Geosci. Model Dev., 7, 387–405, https://doi.org/10.5194/gmd-7-387-2014, 2014.
Fiddes, J., Aalstad, K., and Westermann, S.: Hyper-resolution ensemble-based snow reanalysis in mountain regions using clustering, Hydrol. Earth Syst. Sci., 23, 4717–4736, https://doi.org/10.5194/hess-23-4717-2019, 2019.
García-Ruiz, J. M., López-Moreno, I. I., Vicente-Serrano, S. M.,
Lasanta-Martínez, T., and Beguería, S.: Mediterranean water resources
in a global change scenario, Earth-Sci. Rev., 105, 121–139,
https://doi.org/10.1016/j.earscirev.2011.01.006, 2011.
Gascoin, S., Hagolle, O., Huc, M., Jarlan, L., Dejoux, J.-F., Szczypta, C., Marti, R., and Sánchez, R.: A snow cover climatology for the Pyrenees from MODIS snow products, Hydrol. Earth Syst. Sci., 19, 2337–2351, https://doi.org/10.5194/hess-19-2337-2015, 2015.
Gascoin, S., Grizonnet, M., Bouchet, M., Salgues, G., and Hagolle, O.: Theia Snow collection: high-resolution operational snow cover maps from Sentinel-2 and Landsat-8 data, Earth Syst. Sci. Data, 11, 493–514, https://doi.org/10.5194/essd-11-493-2019, 2019.
Gómez, B. and Miguez-Macho, G.: The impact of wave number selection and
spin-up time in spectral nudging, Q. J. Roy. Meteor. Soc., 143, 1772–1786,
https://doi.org/10.1002/qj.3032, 2017.
Günther, D., Marke, T., Essery, R., and Strasser, U.: Uncertainties in
Snowpack Simulations – Assessing the Impact of Model Structure, Parameter
Choice, and Forcing Data Error on Point-Scale Energy Balance Snow Model
Performance, Water Resour. Res., 55, 2779–2800,
https://doi.org/10.1029/2018WR023403, 2019.
Gutmann, E. D., Rasmussen, R. M., Liu, C., Ikeda, K., Gochis, D. J., Clark,
M. P., Dudhia, J., and Thompson, G.: A comparison of statistical and dynamical
downscaling of winter precipitation over complex terrain, J. Climate, 25,
262–281, https://doi.org/10.1175/2011JCLI4109.1, 2012.
Gutmann, E. D., Barstad, I., Clark, M. P., Arnold, J. R., and Rasmussen, R. M.: The Intermediate Complexity Atmospheric Research Model, J. Hydrometeorol., 17, 957–973, https://doi.org/10.1175/JHM-D-15-0155.1, 2016a.
Gutmann, E. D., Barstad, I., Clark, M. P., Arnold, J. R., and Rasmussen, R. M.: The Intermediate Complexity Atmospheric Research model (ICAR), available at: https://github.com/NCAR/icar (last access: 14 July 2021), 2016b.
Hall, D. K. and Riggs, G. A.: MODIS/Aqua Snow Cover Daily L3 Global 500 m SIN
Grid, Version 6, NASA Natl. Snow Ice Data Cent. Distrib. Act. Arch. Center,
Boulder, Coloroda, USA, https://doi.org/10.5067/MODIS/MYD10A1.006, 2016.
Hall, D. K., Riggs, G. A., and Salomonson, V.: MODIS/Terra Snow Cover 8-day L3
Global 500 m Grid V005, Natl. Snow Ice Data Cent., Colorodo, USA, 2006.
Harder, P. and Pomeroy, J.: Estimating precipitation phase using a
psychrometric energy balance method, Hydrol. Process., 27, 1901–1914,
https://doi.org/10.1002/hyp.9799, 2013.
Herrero, J. and Polo, M. J.: Evaposublimation from the snow in the Mediterranean mountains of Sierra Nevada (Spain), The Cryosphere, 10, 2981–2998, https://doi.org/10.5194/tc-10-2981-2016, 2016.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J. N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020.
Horak, J., Hofer, M., Maussion, F., Gutmann, E., Gohm, A., and Rotach, M. W.: Assessing the added value of the Intermediate Complexity Atmospheric Research (ICAR) model for precipitation in complex topography, Hydrol. Earth Syst. Sci., 23, 2715–2734, https://doi.org/10.5194/hess-23-2715-2019, 2019.
Ikeda, K., Rasmussen, R., Liu, C., Gochis, D., Yates, D., Chen, F., Tewari,
M., Barlage, M., Dudhia, J., Miller, K., Arsenault, K., Grubišić,
V., Thompson, G., and Guttman, E.: Simulation of seasonal snowfall over
Colorado, Atmos. Res., 97, 462–477,
https://doi.org/10.1016/j.atmosres.2010.04.010, 2010.
Jaafar, H., Ahmad, F., Holtmeier, L., and King-Okumu, C.: Refugees, water
balance, and water stress: Lessons learned from Lebanon, Ambio, 49,
1179–1193, https://doi.org/10.1007/s13280-019-01272-0, 2020.
Janjic, Z.: Nonsingular Implementation of the Mellor-Yamada Level 2.5 Scheme
in the NCEP Meso model, NCEP Off. Note, 437, 61 pp., 2002.
Janjic, Z. I.: The step-mountain eta coordinate model: further developments
of the convection, viscous sublayer, and turbulence closure schemes, Mon.
Weather Rev., 122, 927–945,
https://doi.org/10.1175/1520-0493(1994)122<0927:TSMECM>2.0.CO;2, 1994.
Jefferson, A. J.: Seasonal versus transient snow and the elevation dependence
of climate sensitivity in maritime mountainous regions, Geophys. Res. Lett.,
38, L16402, https://doi.org/10.1029/2011GL048346, 2011.
Jomaa, I., Saab, M. T. A., Skaf, S., El Haj, N., and Massaad, R.: Variability in
Spatial Distribution of Precipitation Overall Rugged Topography of Lebanon,
Using TRMM Images, Atmos. Clim. Sci., 9, 369–380,
https://doi.org/10.4236/acs.2019.93026, 2019.
Koeniger, P., Margane, A., Abi-Rizk, J., and Himmelsbach, T.: Stable
isotope-based mean catchment altitudes of springs in the Lebanon Mountains,
Hydrol. Process., 31, 3708–3718, https://doi.org/10.1002/hyp.11291, 2017.
Kuribayashi, M., Noh, N. J., Saitoh, T. M., Tamagawa, I., Wakazuki, Y., and
Muraoka, H.: Comparison of snow water equivalent estimated in central Japan
by high-resolution simulations using different land-surface models, Sci.
Online Lett. Atmos., 9, 148–152, https://doi.org/10.2151/sola.2013-033,
2013.
Legates, D.: Climate models and their simulation of precipitation, Energy
Environ., 25, 1163–1175, https://doi.org/10.1260/0958-305X.25.6-7.1163,
2014.
Liston, G. E.: Representing subgrid snow cover heterogeneities in regional
and global models, J. Climate, 17, 1381–1397,
https://doi.org/10.1175/1520-0442(2004)017<1381:RSSCHI>2.0.CO;2, 2004.
Liston, G. E. and Elder, K.: A distributed snow-evolution modeling system
(snowmodel), J. Hydrometeorol., 7, 1259–1276,
https://doi.org/10.1175/JHM548.1, 2006.
López-Moreno, J. I. and García-Ruiz, J. M.: Influence of snow
accumulation and snowmelt on streamflow in the central Spanish Pyrenees (Influence de l'accumulation et de la fonte de la neige sur les
écoulements dans les Pyrénées centrales espagnoles), Hydrol. Sci.
J., 49, 802, https://doi.org/10.1623/hysj.49.5.787.55135, 2004.
López-Moreno, J. I., Fassnacht, S. R., Beguería, S., and Latron, J. B. P.: Variability of snow depth at the plot scale: implications for mean depth estimation and sampling strategies, The Cryosphere, 5, 617–629, https://doi.org/10.5194/tc-5-617-2011, 2011.
López-Moreno, J. I., Gascoin, S., Herrero, J., Sproles, E. A., Pons, M.,
Alonso-González, E., Hanich, L., Boudhar, A., Musselman, K. N., Molotch,
N. P., Sickman, J., and Pomeroy, J.: Different sensitivities of snowpacks to
warming in Mediterranean climate mountain areas, Environ. Res. Lett., 12, 074006, https://doi.org/10.1088/1748-9326/aa70cb, 2017.
Lundquist, J., Hughes, M., Gutmann, E., and Kapnick, S.: Our skill in modeling
mountain rain and snow is bypassing the skill of our observational networks, B. Am. Meteorol. Soc., 100, 2473–2490,
https://doi.org/10.1175/BAMS-D-19-0001.1, 2019.
Margulis, S. A., Girotto, M., Cortés, G., and Durand, M.: A particle batch
smoother approach to snow water equivalent estimation, J. Hydrometeorol., 16,
1752–1772, https://doi.org/10.1175/JHM-D-14-0177.1, 2015.
Margulis, S. A., Cortés, G., Girotto, M., and Durand, M.: A landsat-era
Sierra Nevada snow reanalysis (1985–2015), J. Hydrometeorol., 17, 1203–1221,
https://doi.org/10.1175/JHM-D-15-0177.1, 2016.
Marty, C., Schlögl, S., Bavay, M., and Lehning, M.: How much can we save? Impact of different emission scenarios on future snow cover in the Alps, The Cryosphere, 11, 517–529, https://doi.org/10.5194/tc-11-517-2017, 2017.
Mernild, S. H., Liston, G. E., Hiemstra, C. A., Malmros, J. K., Yde, J. C.,
and McPhee, J.: The Andes Cordillera. Part I: snow distribution, properties, and
trends (1979–2014), Int. J. Climatol., 37, 1680–1698,
https://doi.org/10.1002/joc.4804, 2017.
Mhawej, M., Faour, G., Fayad, A., and Shaban, A.: Towards an enhanced method to
map snow cover areas and derive snow-water equivalent in Lebanon, J. Hydrol.,
513, 274–282, https://doi.org/10.1016/j.jhydrol.2014.03.058, 2014.
Montavez, J. P., Lopez-Romero, J. M., Jerez, S., Gomez-Navarro, J. J.,
and Jimenez-Guerrero, P.: How much spin-up period is really necessary in
regional climate simulations?, in: Geophysical Research Abstracts, EGU
General Assembly, Vienna, Austria, 19, 2017–15806, 2017.
Nappo, C. J.: The Linear Theory, 2nd edn., International Geophysics, Academic
Press, https://doi.org/10.1016/B978-0-12-385223-6.00002-1, 2012.
Neale, R. B., Chen, C., Lauritzen, P. H., Williamson, D. L., Conley, A. J.,
Smith, A. K., Mills, M., and Morrison, H.: Description of the NCAR Community
Atmosphere Model (CAM 5.0), Ncar/Tn-464+Str 214, available at: https://www.cesm.ucar.edu/models/cesm1.0/cam/docs/description/cam5_desc.pdf (last access: 14 July 2021), 2004.
Niu, G. Y., Yang, Z. L., Mitchell, K. E., Chen, F., Ek, M. B., Barlage, M.,
Kumar, A., Manning, K., Niyogi, D., Rosero, E., Tewari, M., and Xia, Y.: The
community Noah land surface model with multiparameterization options
(Noah-MP): 1. Model description and evaluation with local-scale
measurements, J. Geophys. Res.-Atmos., 116, D12109,
https://doi.org/10.1029/2010JD015139, 2011.
Peel, M. C., Finlayson, B. L., and McMahon, T. A.: Updated world map of the Köppen-Geiger climate classification, Hydrol. Earth Syst. Sci., 11, 1633–1644, https://doi.org/10.5194/hess-11-1633-2007, 2007.
Rasmussen, R., Liu, C., Ikeda, K., Gochis, D., Yates, D., Chen, F., Tewari,
M., Barlage, M., Dudhia, J., Yu, W., Miller, K., Arsenault, K.,
Grubišić, V., Thompson, G., and Gutmann, E.: High-resolution coupled
climate runoff simulations of seasonal snowfall over Colorado: A process
study of current and warmer climate, J. Climate, 24, 3015–3048,
https://doi.org/10.1175/2010JCLI3985.1, 2011.
Saavedra, F. A., Kampf, S. K., Fassnacht, S. R., and Sibold, J. S.: A snow
climatology of the Andes Mountains from MODIS snow cover data, Int. J.
Climatol., 37, 1526–1539, 2017.
Salomonson, V. V. and Appel, I.: Estimating fractional snow cover from MODIS
using the normalized difference snow index, Remote Sens. Environ., 89,
351–360, https://doi.org/10.1016/j.rse.2003.10.016, 2004.
Schulz, O. and de Jong, C.: Snowmelt and sublimation: field experiments and modelling in the High Atlas Mountains of Morocco, Hydrol. Earth Syst. Sci., 8, 1076–1089, https://doi.org/10.5194/hess-8-1076-2004, 2004.
Skamarock, W. C., Klemp, J. B., Dudhia, J. B., Gill, D. O., Barker, D. M., Duda, M. G., Huang, X.-Y., Wang, W., and Powers, J. G.: A description of the Advanced Research WRF Version 3, NCAR Technical Note TN-475+STR, Tech. Rep., 113, https://doi.org/10.5065/D68S4MVH, 2008a.
Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Duda, M. G., Huang, X.-Y., Wang, W., and Powers, J. G.: The official repository for the Weather Research and Forecasting (WRF) model, available at: https://github.com/wrf-model/WRF (last access: 14 July 2021), 2008b.
Smolarkiewicz, P. K. and Margolin, L. G.: MPDATA: A Finite-Difference Solver for
Geophysical Flows, J. Comput. Phys., 140, 459–480, https://doi.org/10.1006/jcph.1998.5901,
1998.
Sproles, E. A., Nolin, A. W., Rittger, K., and Painter, T. H.: Climate change impacts on maritime mountain snowpack in the Oregon Cascades, Hydrol. Earth Syst. Sci., 17, 2581–2597, https://doi.org/10.5194/hess-17-2581-2013, 2013.
Suzuki, K. and Zupanski, M.: Uncertainty in solid precipitation and snow depth
prediction for Siberia using the Noah and Noah-MP land surface models,
Front. Earth Sci., 12, 672–682, https://doi.org/10.1007/s11707-018-0691-2,
2018.
Tarek, M., Brissette, F. P., and Arsenault, R.: Evaluation of the ERA5 reanalysis as a potential reference dataset for hydrological modelling over North America, Hydrol. Earth Syst. Sci., 24, 2527–2544, https://doi.org/10.5194/hess-24-2527-2020, 2020.
Telesca, L., Shaban, A., Gascoin, S., Darwich, T., Drapeau, L., Hage, M. El,
and Faour, G.: Characterization of the time dynamics of monthly satellite snow
cover data on Mountain Chains in Lebanon, J. Hydrol., 519, 3214–3222,
https://doi.org/10.1016/j.jhydrol.2014.10.037, 2014.
Thompson, G., Field, P. R., Rasmussen, R. M., and Hall, W. D.: Explicit forecasts
of winter precipitation using an improved bulk microphysics scheme. Part II:
Implementation of a new snow parameterization, Mon. Weather Rev., 136,
5095–5115, https://doi.org/10.1175/2008MWR2387.1, 2008.
Van Leeuwen, P. J.: Particle filtering in geophysical systems, Mon. Weather
Rev., 137, 4089–4114, https://doi.org/10.1175/2009MWR2835.1, 2009.
van Pelt, W. J. J., Kohler, J., Liston, G. E., Hagen, J. O., Luks, B., Reijmer,
C. H., and Pohjola, V. A.: Multidecadal climate and seasonal snow conditions in
Svalbard, J. Geophys. Res.-Earth, 121, 2100–2117,
https://doi.org/10.1002/2016JF003999, 2016.
Verseghy, D. L.: Class – A Canadian land surface scheme for GCMS. I. Soil
model, Int. J. Climatol., 11, 111–133,
https://doi.org/10.1002/joc.3370110202, 1991.
Viviroli, D., Dürr, H. H., Messerli, B., Meybeck, M., and Weingartner, R.:
Mountains of the world, water towers for humanity: Typology, mapping, and
global significance, Water Resour. Res., 43,
https://doi.org/10.1029/2006WR005653, 2007.
Von Storch, H., Langenberg, H., and Feser, F.: A spectral nudging technique for
dynamical downscaling purposes, Mon. Weather Rev., 128, 3664–3673,
https://doi.org/10.1175/1520-0493(2000)128<3664:ASNTFD>2.0.CO;2, 2000.
Waldron, K. M., Paegle, J., and Horel, J. D.: Sensitivity of a spectrally filtered
and nudged limited-area model to outer model options, Mon. Weather Rev., 124,
529–547, https://doi.org/10.1175/1520-0493(1996)124<0529:SOASFA>2.0.CO;2, 1996.
Wang, C., Graham, R. M., Wang, K., Gerland, S., and Granskog, M. A.: Comparison of ERA5 and ERA-Interim near-surface air temperature, snowfall and precipitation over Arctic sea ice: effects on sea ice thermodynamics and evolution, The Cryosphere, 13, 1661–1679, https://doi.org/10.5194/tc-13-1661-2019, 2019.
Wang, D., Morton, D., Masek, J., Wu, A., Nagol, J., Xiong, X., Levy, R.,
Vermote, E., and Wolfe, R.: Impact of sensor degradation on the MODIS NDVI time
series, Remote Sens. Environ., 119, 55–61,
https://doi.org/10.1016/J.RSE.2011.12.001, 2012.
Wegmann, M., Orsolini, Y., Dutra, E., Bulygina, O., Sterin, A., and Brönnimann, S.: Eurasian snow depth in long-term climate reanalyses, The Cryosphere, 11, 923–935, https://doi.org/10.5194/tc-11-923-2017, 2017.
Wu, X., Che, T., Li, X., Wang, N., and Yang, X.: Slower Snowmelt in Spring Along
With Climate Warming Across the Northern Hemisphere, Geophys. Res. Lett., 45,
12331–12339, https://doi.org/10.1029/2018GL079511, 2018.
Yilmaz, Y., Aalstad, K., and Sen, O.: Multiple Remotely Sensed Lines of Evidence
for a Depleting Seasonal Snowpack in the Near East, Remote Sens., 11, 483,
https://doi.org/10.3390/rs11050483, 2019.
Short summary
Snow water resources represent a key hydrological resource for the Mediterranean regions, where most of the precipitation falls during the winter months. This is the case for Lebanon, where snowpack represents 31 % of the spring flow. We have used models to generate snow information corrected by means of remote sensing snow cover retrievals. Our results highlight the high temporal variability in the snowpack in Lebanon and its sensitivity to further warming caused by its hypsography.
Snow water resources represent a key hydrological resource for the Mediterranean regions, where...
