Articles | Volume 19, issue 3
https://doi.org/10.5194/hess-19-1339-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-19-1339-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
10 Mar 2015
Research article |
| 10 Mar 2015
Fractional snow-covered area parameterization over complex topography
WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
A. van Herwijnen
WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
J. Magnusson
WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
T. Jonas
WSL Institute for Snow and Avalanche Research SLF, Davos Dorf, Switzerland
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Mathieu Le Breton, Éric Larose, Laurent Baillet, Yves Lejeune, and Alec van Herwijnen
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Bastian Bergfeld, Alec van Herwijnen, Grégoire Bobillier, Philipp L. Rosendahl, Philipp Weißgraeber, Valentin Adam, Jürg Dual, and Jürg Schweizer
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Stephanie Mayer, Alec van Herwijnen, Frank Techel, and Jürg Schweizer
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Cristina Pérez-Guillén, Frank Techel, Martin Hendrick, Michele Volpi, Alec van Herwijnen, Tasko Olevski, Guillaume Obozinski, Fernando Pérez-Cruz, and Jürg Schweizer
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Antoine Guillemot, Alec van Herwijnen, Eric Larose, Stephanie Mayer, and Laurent Baillet
The Cryosphere, 15, 5805–5817, https://doi.org/10.5194/tc-15-5805-2021, https://doi.org/10.5194/tc-15-5805-2021, 2021
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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 Cryosphere, 15, 3539–3553, https://doi.org/10.5194/tc-15-3539-2021, https://doi.org/10.5194/tc-15-3539-2021, 2021
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The modern picture of the snow slab avalanche release process involves a
dynamic crack propagation phasein which a whole slope becomes detached. The present work contains the first field methodology which provides the temporal and spatial resolution necessary to study this phase. We demonstrate the versatile capabilities and accuracy of our method by revealing intricate dynamics and present how to determine relevant characteristics of crack propagation such as crack speed.
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.
Michaela Wenner, Clément Hibert, Alec van Herwijnen, Lorenz Meier, and Fabian Walter
Nat. Hazards Earth Syst. Sci., 21, 339–361, https://doi.org/10.5194/nhess-21-339-2021, https://doi.org/10.5194/nhess-21-339-2021, 2021
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Marius G. Floriancic, Wouter R. Berghuijs, Tobias Jonas, James W. Kirchner, and Peter Molnar
Hydrol. Earth Syst. Sci., 24, 5423–5438, https://doi.org/10.5194/hess-24-5423-2020, https://doi.org/10.5194/hess-24-5423-2020, 2020
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Deep ice layers may form in the snowpack due to preferential water flow with impacts on the snowpack mechanical, hydrological and thermodynamical properties. We studied their formation and evolution at a high-altitude alpine site, combining a comprehensive observation dataset at a daily frequency (with traditional snowpack observations, penetration resistance and radar measurements) and detailed snowpack modeling, including a new parameterization of ice formation in the 1-D SNOWPACK model.
Frank Techel, Kurt Winkler, Matthias Walcher, Alec van Herwijnen, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 20, 1941–1953, https://doi.org/10.5194/nhess-20-1941-2020, https://doi.org/10.5194/nhess-20-1941-2020, 2020
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Snow instability tests, like the extended column test (ECT), provide valuable information regarding point snow instability. A large data set of ECT – together with information on slope instability – was explored. The findings clearly show that combining information regarding propagation propensity and fracture initiation provided the best correlation with slope instability. A new four-class stability interpretation scheme is proposed for ECT results.
Neige Calonne, Bettina Richter, Henning Löwe, Cecilia Cetti, Judith ter Schure, Alec Van Herwijnen, Charles Fierz, Matthias Jaggi, and Martin Schneebeli
The Cryosphere, 14, 1829–1848, https://doi.org/10.5194/tc-14-1829-2020, https://doi.org/10.5194/tc-14-1829-2020, 2020
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During winter 2015–2016, the standard program to monitor the structure and stability of the snowpack at Weissflujoch, Swiss Alps, was complemented by additional measurements to compare between various traditional and newly developed techniques. Snow micro-penetrometer measurements allowed monitoring of the evolution of the snowpack's internal structure at a daily resolution throughout the winter. We show the potential of such high-resolution data for detailed evaluations of snowpack models.
Emanuele Marchetti, Alec van Herwijnen, Marc Christen, Maria Cristina Silengo, and Giulia Barfucci
Earth Surf. Dynam., 8, 399–411, https://doi.org/10.5194/esurf-8-399-2020, https://doi.org/10.5194/esurf-8-399-2020, 2020
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We present infrasonic and seismic array data of a powder snow avalanche, that was released on 5 February 2016, in the Dischma valley nearby Davos, Switzerland. Combining information derived from both arrays, we show how infrasound and seismic energy are radiated from different sources acting along the path. Moreover, infrasound transmits to the ground and affects the recorded seismic signal. Results highlight the benefits of combined seismo-acoustic array analyses for monitoring and research.
Nora Helbig, David Moeser, Michaela Teich, Laure Vincent, Yves Lejeune, Jean-Emmanuel Sicart, and Jean-Matthieu Monnet
Hydrol. Earth Syst. Sci., 24, 2545–2560, https://doi.org/10.5194/hess-24-2545-2020, https://doi.org/10.5194/hess-24-2545-2020, 2020
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Snow retained in the forest canopy (snow interception) drives spatial variability of the subcanopy snow accumulation. As such, accurately describing snow interception in models is of importance for various applications such as hydrological, weather, and climate predictions. We developed descriptions for the spatial mean and variability of snow interception. An independent evaluation demonstrated that the novel models can be applied in coarse land surface model grid cells.
Grégoire Bobillier, Bastian Bergfeld, Achille Capelli, Jürg Dual, Johan Gaume, Alec van Herwijnen, and Jürg Schweizer
The Cryosphere, 14, 39–49, https://doi.org/10.5194/tc-14-39-2020, https://doi.org/10.5194/tc-14-39-2020, 2020
Bettina Richter, Jürg Schweizer, Mathias W. Rotach, and Alec van Herwijnen
The Cryosphere, 13, 3353–3366, https://doi.org/10.5194/tc-13-3353-2019, https://doi.org/10.5194/tc-13-3353-2019, 2019
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Information on snow stability is important for avalanche forecasting. To improve the stability estimation in the snow cover model SNOWPACK, we suggested an improved parameterization for the critical crack length. We compared 3 years of field data to SNOWPACK simulations. The match between observed and modeled critical crack lengths greatly improved, and critical weak layers appear more prominently in the modeled vertical profile of critical crack length.
Matthias Heck, Alec van Herwijnen, Conny Hammer, Manuel Hobiger, Jürg Schweizer, and Donat Fäh
Earth Surf. Dynam., 7, 491–503, https://doi.org/10.5194/esurf-7-491-2019, https://doi.org/10.5194/esurf-7-491-2019, 2019
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We used continuous seismic data from two small aperture geophone arrays deployed in the region above Davos in the eastern Swiss Alps to develop a machine learning workflow to automatically identify signals generated by snow avalanches. Our results suggest that the method presented could be used to identify major avalanche periods and highlight the importance of array processing techniques for the automatic classification of avalanches in seismic data.
Matthias Heck, Conny Hammer, Alec van Herwijnen, Jürg Schweizer, and Donat Fäh
Nat. Hazards Earth Syst. Sci., 18, 383–396, https://doi.org/10.5194/nhess-18-383-2018, https://doi.org/10.5194/nhess-18-383-2018, 2018
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In this study we use hidden Markov models, a machine learning algorithm to automatically identify avalanche events in a continuous seismic data set recorded during the winter 2010. With additional post processing steps, we detected around 70 avalanche events. Although not every detection could be confirmed as an avalanche, we clearly identified the two main avalanche periods of the winter season 2010 in our classification results.
Roman Juras, Sebastian Würzer, Jirka Pavlásek, Tomáš Vitvar, and Tobias Jonas
Hydrol. Earth Syst. Sci., 21, 4973–4987, https://doi.org/10.5194/hess-21-4973-2017, https://doi.org/10.5194/hess-21-4973-2017, 2017
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This research investigates the rainwater dynamics in the snowpack under artificial rain-on-snow events. Deuterium-enriched water was sprayed on the isolated snowpack and rainwater was further identified in the runoff. We found that runoff from cold snowpack was created faster than from the ripe snowpack. Runoff from the cold snowpack also contained more rainwater compared to the ripe snowpack. These results are valuable for further snowpack runoff forecasting.
Sebastian Würzer, Nander Wever, Roman Juras, Michael Lehning, and Tobias Jonas
Hydrol. Earth Syst. Sci., 21, 1741–1756, https://doi.org/10.5194/hess-21-1741-2017, https://doi.org/10.5194/hess-21-1741-2017, 2017
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We discuss a dual-domain water transport model in a physics-based snowpack model to account for preferential flow (PF) in addition to matrix flow. So far no operationally used snow model has explicitly accounted for PF. The new approach is compared to existing water transport models and validated against in situ data from sprinkling and natural rain-on-snow (ROS) events. Our work demonstrates the benefit of considering PF in modelling hourly snowpack runoff, especially during ROS conditions.
Nena Griessinger, Franziska Mohr, and Tobias Jonas
The Cryosphere Discuss., https://doi.org/10.5194/tc-2016-295, https://doi.org/10.5194/tc-2016-295, 2017
Revised manuscript not accepted
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We demonstrate the potential of ground penetrating radar for efficient and accurate measurements of snow depth and snow water equivalent when liquid water is present in the snowpack. We were able to derive snow ablation rates with high accuracy from repeated measurements.
We present the design of our light-weight setup consisting of a common-mid-point assembly on a plastic sled, which is mobile even in complex heterogeneous terrain like our investigated field sites in the eastern Swiss Alps.
Johan Gaume, Alec van Herwijnen, Guillaume Chambon, Nander Wever, and Jürg Schweizer
The Cryosphere, 11, 217–228, https://doi.org/10.5194/tc-11-217-2017, https://doi.org/10.5194/tc-11-217-2017, 2017
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Based on DEM simulations we developed a new model for the onset of crack propagation in snow slab avalanche release. The model reconciles past approaches by considering the complex interplay between slab elasticity and the mechanical behavior of the weak layer including its structural collapse. The model agrees with extensive field data and can reproduce crack propagation on low-angle terrain and the decrease in critical crack length with increasing slope angle observed in numerical experiments.
Jürg Schweizer, Benjamin Reuter, Alec van Herwijnen, Bettina Richter, and Johan Gaume
The Cryosphere, 10, 2637–2653, https://doi.org/10.5194/tc-10-2637-2016, https://doi.org/10.5194/tc-10-2637-2016, 2016
Nena Griessinger, Jan Seibert, Jan Magnusson, and Tobias Jonas
Hydrol. Earth Syst. Sci., 20, 3895–3905, https://doi.org/10.5194/hess-20-3895-2016, https://doi.org/10.5194/hess-20-3895-2016, 2016
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In Alpine catchments, snowmelt is a major contribution to runoff. In this study, we address the question of whether the performance of a hydrological model can be enhanced by integrating data from an external snow monitoring system. To this end, a hydrological model was driven with snowmelt input from snow models of different complexities. Best performance was obtained with a snow model, which utilized data assimilation, in particular for catchments at higher elevations and for snow-rich years.
Fabiano Monti, Johan Gaume, Alec van Herwijnen, and Jürg Schweizer
Nat. Hazards Earth Syst. Sci., 16, 775–788, https://doi.org/10.5194/nhess-16-775-2016, https://doi.org/10.5194/nhess-16-775-2016, 2016
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We propose a new approach based on a simplification of the multi-layered elasticity theory in order to easily compute the additional stress due to a skier at the depth of the weak layer, taking into account the layering of the snow slab and the substratum. The method was tested on simplified snow profiles, then on manually observed snow profiles including a stability test and, finally, on simulated snow profiles, thereby showing the promise of our approach.
Michal Jenicek, Jan Seibert, Massimiliano Zappa, Maria Staudinger, and Tobias Jonas
Hydrol. Earth Syst. Sci., 20, 859–874, https://doi.org/10.5194/hess-20-859-2016, https://doi.org/10.5194/hess-20-859-2016, 2016
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We quantified how long snowmelt affects runoff, and we estimated the sensitivity of catchments to changes in snowpack. This is relevant as the increase of air temperature might cause decreased snow storage. We used time series from 14 catchments in Switzerland. On average, a decrease of maximum snow storage by 10 % caused a decrease of minimum discharge in July by 2 to 9 %. The results showed a higher sensitivity of summer low flow to snow in alpine catchments compared to pre-alpine catchments.
J. Gaume, A. van Herwijnen, G. Chambon, K. W. Birkeland, and J. Schweizer
The Cryosphere, 9, 1915–1932, https://doi.org/10.5194/tc-9-1915-2015, https://doi.org/10.5194/tc-9-1915-2015, 2015
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We proposed a new approach to characterize the dynamic phase of crack propagation in weak snowpack layers as well as fracture arrest propensity by means of numerical "propagation saw test" simulations based on the discrete element method. Crack propagation speed and distance before fracture arrest were derived from the simulations for different snowpack configurations and mechanical properties. Numerical and experimental results were compared and the mechanical processes at play were discussed.
F. Kobierska, T. Jonas, J. W. Kirchner, and S. M. Bernasconi
Hydrol. Earth Syst. Sci., 19, 3681–3693, https://doi.org/10.5194/hess-19-3681-2015, https://doi.org/10.5194/hess-19-3681-2015, 2015
I. Gouttevin, M. Lehning, T. Jonas, D. Gustafsson, and M. Mölder
Geosci. Model Dev., 8, 2379–2398, https://doi.org/10.5194/gmd-8-2379-2015, https://doi.org/10.5194/gmd-8-2379-2015, 2015
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We improve the canopy module of a very detailed snow model, SNOWPACK, with a view of a more consistent representation of the sub-canopy energy balance with regard to the snowpack.
We show that adding a formulation of (i) the canopy heat capacity and (ii) a lowermost canopy layer (alike trunk + solar shaded leaves) yields significant improvement in the representation of sub-canopy incoming long-wave radiations, especially at nighttime. This energy is an important contributor to snowmelt.
B. Reuter, J. Schweizer, and A. van Herwijnen
The Cryosphere, 9, 837–847, https://doi.org/10.5194/tc-9-837-2015, https://doi.org/10.5194/tc-9-837-2015, 2015
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We present a novel approach to estimate point snow instability based on snow mechanical properties from snow micro-penetrometer measurements. This is the first approach that takes into account the essential processes involved in dry-snow slab avalanche release: failure initiation and crack propagation. Comparison with field observations confirms that the two-step calculation of a stability criterion and a critical crack length is suited to describe point snow instability.
M. Stähli, M. Sättele, C. Huggel, B. W. McArdell, P. Lehmann, A. Van Herwijnen, A. Berne, M. Schleiss, A. Ferrari, A. Kos, D. Or, and S. M. Springman
Nat. Hazards Earth Syst. Sci., 15, 905–917, https://doi.org/10.5194/nhess-15-905-2015, https://doi.org/10.5194/nhess-15-905-2015, 2015
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This review paper describes the state of the art in monitoring and predicting rapid mass movements for early warning. It further presents recent innovations in observation technologies and modelling to be used in future early warning systems (EWS). Finally, the paper proposes avenues towards successful implementation of next-generation EWS.
Y. Bühler, M. Marty, L. Egli, J. Veitinger, T. Jonas, P. Thee, and C. Ginzler
The Cryosphere, 9, 229–243, https://doi.org/10.5194/tc-9-229-2015, https://doi.org/10.5194/tc-9-229-2015, 2015
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We are able to map snow depth over large areas ( > 100km2) using airborne digital photogrammetry. Digital photogrammetry is more economical than airborne Laser Scanning but slightly less accurate. Comparisons to independent snow depth measurements reveal an accuracy of about 30cm. Spatial continuous mapping of snow depth is a major step forward compared to point measurements usually applied today. Limitations are steep slopes (> 50°) and areas covered by trees and scrubs.
N. Wever, T. Jonas, C. Fierz, and M. Lehning
Hydrol. Earth Syst. Sci., 18, 4657–4669, https://doi.org/10.5194/hess-18-4657-2014, https://doi.org/10.5194/hess-18-4657-2014, 2014
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We simulated a severe rain-on-snow event in the Swiss Alps in October 2011 with a detailed multi-layer snow cover model. We found a strong modulating effect of the incoming rainfall signal by the snow cover. Initially, water from both rainfall and snow melt was absorbed by the snowpack. But once the snowpack released the stored water, simulated outflow rates exceeded rainfall and snow melt rates. The simulations suggest that structural snowpack changes enhanced the outflow during this event.
E. H. Bair, R. Simenhois, A. van Herwijnen, and K. Birkeland
The Cryosphere, 8, 1407–1418, https://doi.org/10.5194/tc-8-1407-2014, https://doi.org/10.5194/tc-8-1407-2014, 2014
F. Hüsler, T. Jonas, M. Riffler, J. P. Musial, and S. Wunderle
The Cryosphere, 8, 73–90, https://doi.org/10.5194/tc-8-73-2014, https://doi.org/10.5194/tc-8-73-2014, 2014
Related subject area
Subject: Hydrometeorology | Techniques and Approaches: Theory development
Variation and attribution of probable maximum precipitation of China using a high-resolution dataset in a changing climate
Drought cascades across multiple systems in Central Asia identified based on the dynamic space–time motion approach
What is the Priestley–Taylor wet-surface evaporation parameter? Testing four hypotheses
Understanding the diurnal cycle of land–atmosphere interactions from flux site observations
Breakdown in precipitation–temperature scaling over India predominantly explained by cloud-driven cooling
Historical droughts manifest an abrupt shift to a wetter Tibetan Plateau
Citizen rain gauges improve hourly radar rainfall bias correction using a two-step Kalman filter
Dynamical forcings in heavy precipitation events over Italy: lessons from the HyMeX SOP1 campaign
Water vapor isotopes indicating rapid shift among multiple moisture sources for the 2018–2019 winter extreme precipitation events in southeastern China
Spatiotemporal and cross-scale interactions in hydroclimate variability: a case-study in France
Relative humidity gradients as a key constraint on terrestrial water and energy fluxes
A climatological benchmark for operational radar rainfall bias reduction
The precipitation variability of the wet and dry season at the interannual and interdecadal scales over eastern China (1901–2016): the impacts of the Pacific Ocean
Flash drought onset over the contiguous United States: sensitivity of inventories and trends to quantitative definitions
A skewed perspective of the Indian rainfall–El Niño–Southern Oscillation (ENSO) relationship
Imprints of evaporative conditions and vegetation type in diurnal temperature variations
A universal Standardized Precipitation Index candidate distribution function for observations and simulations
A review of the complementary principle of evaporation: from the original linear relationship to generalized nonlinear functions
Model representation of the coupling between evapotranspiration and soil water content at different depths
Combined impacts of ENSO and MJO on the 2015 growing season drought on the Canadian Prairies
Exploring the relationships between warm-season precipitation, potential evaporation, and “apparent” potential evaporation at site scale
Future extreme precipitation intensities based on a historic event
Interannual-to-multidecadal hydroclimate variability and its sectoral impacts in northeastern Argentina
Impact of ENSO regimes on developing- and decaying-phase precipitation during rainy season in China
Variations in the correlation between teleconnections and Taiwan's streamflow
A gain–loss framework based on ensemble flow forecasts to switch the urban drainage–wastewater system management towards energy optimization during dry periods
The residence time of water in the atmosphere revisited
A systematic assessment of drought termination in the United Kingdom
From meteorological to hydrological drought using standardised indicators
Impact of two different types of El Niño events on runoff over the conterminous United States
Flood sensitivity of the Bavarian Alpine Foreland since the late Middle Ages in the context of internal and external climate forcing factors
Novel indices for the comparison of precipitation extremes and floods: an example from the Czech territory
Multi-annual droughts in the English Lowlands: a review of their characteristics and climate drivers in the winter half-year
Comment on "Technical Note: On the Matt–Shuttleworth approach to estimate crop water requirements" by Lhomme et al. (2014)
A review of droughts on the African continent: a geospatial and long-term perspective
Synchronicity of historical dry spells in the Southern Hemisphere
Continental moisture recycling as a Poisson process
Linking ENSO and heavy rainfall events over coastal British Columbia through a weather pattern classification
Impact of elevation and weather patterns on the isotopic composition of precipitation in a tropical montane rainforest
A new perspective on the spatio-temporal variability of soil moisture: temporal dynamics versus time-invariant contributions
Understanding hydroclimate processes in the Murray-Darling Basin for natural resources management
An analytical model for soil-atmosphere feedback
Spatial horizontal correlation characteristics in the land data assimilation of soil moisture
On the factors influencing surface-layer energy closure and their seasonal variability over the semi-arid Loess Plateau of Northwest China
Spatial moments of catchment rainfall: rainfall spatial organisation, basin morphology, and flood response
Scaling and trends of hourly precipitation extremes in two different climate zones – Hong Kong and the Netherlands
The response of Iberian rivers to the North Atlantic Oscillation
Copula-based downscaling of spatial rainfall: a proof of concept
Towards understanding hydroclimatic change in Victoria, Australia – preliminary insights into the "Big Dry"
Extracting statistical parameters of extreme precipitation from a NWP model
Jinghua Xiong, Shenglian Guo, Abhishek, Jiabo Yin, Chongyu Xu, Jun Wang, and Jing Guo
Hydrol. Earth Syst. Sci., 28, 1873–1895, https://doi.org/10.5194/hess-28-1873-2024, https://doi.org/10.5194/hess-28-1873-2024, 2024
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Temporal variability and spatial heterogeneity of climate systems challenge accurate estimation of probable maximum precipitation (PMP) in China. We use high-resolution precipitation data and climate models to explore the variability, trends, and shifts of PMP under climate change. Validated with multi-source estimations, our observations and simulations show significant spatiotemporal divergence of PMP over the country, which is projected to amplify in future due to land–atmosphere coupling.
Lu Tian, Markus Disse, and Jingshui Huang
Hydrol. Earth Syst. Sci., 27, 4115–4133, https://doi.org/10.5194/hess-27-4115-2023, https://doi.org/10.5194/hess-27-4115-2023, 2023
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Anthropogenic global warming accelerates the drought evolution in the water cycle, increasing the unpredictability of drought. The evolution of drought is stealthy and challenging to track. This study proposes a new framework to capture the high-precision spatiotemporal progression of drought events in their evolutionary processes and characterize their feature further. It is crucial for addressing the systemic risks within the hydrological cycle associated with drought mitigation.
Richard D. Crago, Jozsef Szilagyi, and Russell J. Qualls
Hydrol. Earth Syst. Sci., 27, 3205–3220, https://doi.org/10.5194/hess-27-3205-2023, https://doi.org/10.5194/hess-27-3205-2023, 2023
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The Priestley–Taylor equation is widely used in hydrologic, climate, and meteorological models to estimate evaporation. α represents the impact of dry air that is carried into the region; this occurs even in extensive saturated regions. Four hypotheses regarding the nature of α are evaluated. Data from 171 FLUXNET stations were used to test the hypotheses. The best-supported hypothesis sees α as a constant fraction of the distance between theoretical minimum and maximum values.
Eunkyo Seo and Paul A. Dirmeyer
Hydrol. Earth Syst. Sci., 26, 5411–5429, https://doi.org/10.5194/hess-26-5411-2022, https://doi.org/10.5194/hess-26-5411-2022, 2022
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This study presents the climatology of the observed land–atmosphere interactions on a subdaily timescale during the warm season from flux site observations. Multivariate metrics are employed to examine the land, atmosphere, and combined couplings, and a mixing diagram is adopted to understand the coevolution of the moist and thermal energy budget within the atmospheric mixed layer. The diurnal cycles of both mixing diagrams and hourly land–atmosphere couplings exhibit hysteresis.
Sarosh Alam Ghausi, Subimal Ghosh, and Axel Kleidon
Hydrol. Earth Syst. Sci., 26, 4431–4446, https://doi.org/10.5194/hess-26-4431-2022, https://doi.org/10.5194/hess-26-4431-2022, 2022
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The observed response of extreme precipitation to global warming remains unclear with significant regional variations. We show that a large part of this uncertainty can be removed when the imprint of clouds in surface temperatures is removed. We used a thermodynamic systems approach to remove the cloud radiative effect from temperatures. We then found that precipitation extremes intensified with global warming at positive rates which is consistent with physical arguments and model simulations.
Yongwei Liu, Yuanbo Liu, Wen Wang, Han Zhou, and Lide Tian
Hydrol. Earth Syst. Sci., 26, 3825–3845, https://doi.org/10.5194/hess-26-3825-2022, https://doi.org/10.5194/hess-26-3825-2022, 2022
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This study investigated the wetting and drying of the Tibetan Plateau (TP) from variations in soil moisture (SM) droughts. We found the TP experienced an abrupt and significant wetting shift in the middle to late 1990s, not merely the steady trends given in literature. This shift is dominated by precipitation and attributed to the North Atlantic Oscillation. The wetting shift indicates a climate regime change. Our innovative work provides implications for further knowledge of the TP climate.
Punpim Puttaraksa Mapiam, Monton Methaprayun, Thom Bogaard, Gerrit Schoups, and Marie-Claire Ten Veldhuis
Hydrol. Earth Syst. Sci., 26, 775–794, https://doi.org/10.5194/hess-26-775-2022, https://doi.org/10.5194/hess-26-775-2022, 2022
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The density of rain gauge networks plays an important role in radar rainfall bias correction. In this work, we aimed to assess the extent to which daily rainfall observations from a dense network of citizen scientists improve the accuracy of hourly radar rainfall estimates in the Tubma Basin, Thailand. Results show that citizen rain gauges significantly enhance the performance of radar rainfall bias adjustment up to a range of about 40 km from the center of the citizen rain gauge network.
Mario Marcello Miglietta and Silvio Davolio
Hydrol. Earth Syst. Sci., 26, 627–646, https://doi.org/10.5194/hess-26-627-2022, https://doi.org/10.5194/hess-26-627-2022, 2022
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The main results emerging from the HyMeX SOP1 campaign and in the subsequent research activity in three Italian target areas are highlighted through conceptual models and through the identification of the relevant mesoscale environmental characteristics conducive to heavy rain events.
Tao Xu, Hongxi Pang, Zhaojun Zhan, Wangbin Zhang, Huiwen Guo, Shuangye Wu, and Shugui Hou
Hydrol. Earth Syst. Sci., 26, 117–127, https://doi.org/10.5194/hess-26-117-2022, https://doi.org/10.5194/hess-26-117-2022, 2022
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In this study, we presented stable isotopes in atmospheric water vapor and precipitation for five extreme winter precipitation events in Nanjing, southeastern China, from December 2018 to February 2019. Our results imply that multiple moisture sources and the rapid shift among them are important conditions for sustaining extreme precipitation events, especially in the relatively cold and dry winter.
Manuel Fossa, Bastien Dieppois, Nicolas Massei, Matthieu Fournier, Benoit Laignel, and Jean-Philippe Vidal
Hydrol. Earth Syst. Sci., 25, 5683–5702, https://doi.org/10.5194/hess-25-5683-2021, https://doi.org/10.5194/hess-25-5683-2021, 2021
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Hydro-climate observations (such as precipitation, temperature, and river discharge time series) reveal very complex behavior inherited from complex interactions among the physical processes that drive hydro-climate viability. This study shows how even small perturbations of a physical process can have large consequences on some others. Those interactions vary spatially, thus showing the importance of both temporal and spatial dimensions in better understanding hydro-climate variability.
Yeonuk Kim, Monica Garcia, Laura Morillas, Ulrich Weber, T. Andrew Black, and Mark S. Johnson
Hydrol. Earth Syst. Sci., 25, 5175–5191, https://doi.org/10.5194/hess-25-5175-2021, https://doi.org/10.5194/hess-25-5175-2021, 2021
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Here, we present a novel physically based evaporation model to demonstrate that vertical relative humidity (RH) gradients from the land surface to the atmosphere tend to evolve towards zero due to land–atmosphere equilibration processes. Collapsing RH gradients on daily to yearly timescales indicate an emergent land–atmosphere equilibrium, making it possible to determine evapotranspiration using only meteorological information, independent of land surface conditions and vegetation controls.
Ruben Imhoff, Claudia Brauer, Klaas-Jan van Heeringen, Hidde Leijnse, Aart Overeem, Albrecht Weerts, and Remko Uijlenhoet
Hydrol. Earth Syst. Sci., 25, 4061–4080, https://doi.org/10.5194/hess-25-4061-2021, https://doi.org/10.5194/hess-25-4061-2021, 2021
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Significant biases in real-time radar rainfall products limit the use for hydrometeorological forecasting. We introduce CARROTS (Climatology-based Adjustments for Radar Rainfall in an OperaTional Setting), a set of fixed bias reduction factors to correct radar rainfall products and to benchmark other correction algorithms. When tested for 12 Dutch basins, estimated rainfall and simulated discharges with CARROTS generally outperform those using the operational mean field bias adjustments.
Tao Gao, Fuqiang Cao, Li Dan, Ming Li, Xiang Gong, and Junjie Zhan
Hydrol. Earth Syst. Sci., 25, 1467–1481, https://doi.org/10.5194/hess-25-1467-2021, https://doi.org/10.5194/hess-25-1467-2021, 2021
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The rainfall in eastern China is principally concentrated from April–September. Changes are roughly coincident with phase shifts of the El Niño–Southern Oscillation (ENSO) in both the dry (October–March) and wet (April–September) seasons, and the Pacific Decadal Oscillation (PDO) triggers a stronger effect on precipitation in the wet season. The interannual and interdecadal rainfall variability over eastern China is substantially modulated by drivers originating from the Pacific Ocean.
Mahmoud Osman, Benjamin F. Zaitchik, Hamada S. Badr, Jordan I. Christian, Tsegaye Tadesse, Jason A. Otkin, and Martha C. Anderson
Hydrol. Earth Syst. Sci., 25, 565–581, https://doi.org/10.5194/hess-25-565-2021, https://doi.org/10.5194/hess-25-565-2021, 2021
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Our study of flash droughts' definitions over the United States shows that published definitions yield markedly different inventories of flash drought geography and frequency. Results suggest there are several pathways that can lead to events that are characterized as flash droughts. Lack of consensus across definitions helps to explain apparent contradictions in the literature on trends and indicates the selection of a definition is important for accurate monitoring of different mechanisms.
Justin Schulte, Frederick Policielli, and Benjamin Zaitchik
Hydrol. Earth Syst. Sci., 24, 5473–5489, https://doi.org/10.5194/hess-24-5473-2020, https://doi.org/10.5194/hess-24-5473-2020, 2020
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Wavelet coherence is now a commonly used method for detecting scale-dependent relationships between time series. In this study, the concept of wavelet coherence is generalized to higher-order wavelet coherence methods that quantify the relationship between higher-order statistical moments associated with two time series. The methods are applied to the El Niño–Southern Oscillation (ENSO) and the Indian monsoon to show that the ENSO–Indian monsoon relationship is impacted by ENSO nonlinearity.
Annu Panwar, Maik Renner, and Axel Kleidon
Hydrol. Earth Syst. Sci., 24, 4923–4942, https://doi.org/10.5194/hess-24-4923-2020, https://doi.org/10.5194/hess-24-4923-2020, 2020
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Here we examine the effect of evaporative cooling across different vegetation types. Evaporation cools surface temperature significantly in short vegetation. In the forest, the high aerodynamic conductance explains 56 % of the reduced surface temperature. Therefore, the main cooling agent in the forest is the high aerodynamic conductance and not evaporation. Additionally, we propose the diurnal variation in surface temperature as being a potential indicator of evaporation in short vegetation.
Patrick Pieper, André Düsterhus, and Johanna Baehr
Hydrol. Earth Syst. Sci., 24, 4541–4565, https://doi.org/10.5194/hess-24-4541-2020, https://doi.org/10.5194/hess-24-4541-2020, 2020
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The Standardized Precipitation Index (SPI) is a widely accepted drought index. SPI normalizes the precipitation distribution via a probability density function (PDF). However, which PDF properly normalizes SPI is still disputed. We suggest using a previously mostly overlooked PDF, namely the exponentiated Weibull distribution. The proposed PDF ensures the normality of the index. We demonstrate this – for the first time – for all common accumulation periods in both observations and simulations.
Songjun Han and Fuqiang Tian
Hydrol. Earth Syst. Sci., 24, 2269–2285, https://doi.org/10.5194/hess-24-2269-2020, https://doi.org/10.5194/hess-24-2269-2020, 2020
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The complementary principle is an important methodology for estimating actual evaporation by using routinely observed meteorological variables. This review summaries its 56-year development, focusing on how related studies have shifted from adopting a symmetric linear complementary relationship to employing generalized nonlinear functions. We also compare the polynomial and sigmoid types of generalized complementary functions and discuss their future development.
Jianxiu Qiu, Wade T. Crow, Jianzhi Dong, and Grey S. Nearing
Hydrol. Earth Syst. Sci., 24, 581–594, https://doi.org/10.5194/hess-24-581-2020, https://doi.org/10.5194/hess-24-581-2020, 2020
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Accurately estimating coupling of evapotranspiration (ET) and soil water content (θ) at different depths is key to investigating land–atmosphere interaction. Here we examine whether the model can accurately represent surface θ (θs) versus ET coupling and vertically integrated θ (θv) versus ET coupling. We find that all models agree with observations that θs contains slightly more information with fPET than θv. In addition, an ET scheme is crucial for accurately estimating coupling of θ and ET.
Zhenhua Li, Yanping Li, Barrie Bonsal, Alan H. Manson, and Lucia Scaff
Hydrol. Earth Syst. Sci., 22, 5057–5067, https://doi.org/10.5194/hess-22-5057-2018, https://doi.org/10.5194/hess-22-5057-2018, 2018
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The research started by investigating the 2015 growing season drought over the Canadian Prairies and evolved into investigating the connection between growing season rain deficit in the Prairies and MJO (20–90 days tropical oscillation in convective storms). With warm central Pacific sea surface temperature, strong MJOs in the western Pacific cause Rossby wave trains that propagate downstream and favour upper-level ridges and rain deficits over the Canadian Prairies during the growing season.
Xi Chen and Steven G. Buchberger
Hydrol. Earth Syst. Sci., 22, 4535–4545, https://doi.org/10.5194/hess-22-4535-2018, https://doi.org/10.5194/hess-22-4535-2018, 2018
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Based on warm season data from 259 weather stations across the US, we analyze the correlation between precipitation, potential evaporation, and “apparent” potential evaporation (measured by pan evaporation). Over 93 % of the stations show negative correlation between precipitation and
apparentpotential evaporation, but no clear relationship is shown between precipitation and potential evaporation. The collected data points follow the trend of the newly derived Bouchet–Budyko curve.
Iris Manola, Bart van den Hurk, Hans De Moel, and Jeroen C. J. H. Aerts
Hydrol. Earth Syst. Sci., 22, 3777–3788, https://doi.org/10.5194/hess-22-3777-2018, https://doi.org/10.5194/hess-22-3777-2018, 2018
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In a warmer climate, it is expected that precipitation intensities will increase and form a considerable risk of high-impact precipitation extremes. We investigate how observed extreme precipitation events would look like if they took place in a future warmer climate. This study applies three methods to transform a historic extreme precipitation event in the Netherlands to a similar event in a future warmer climate, thus compiling a
future weatherscenario.
Miguel A. Lovino, Omar V. Müller, Gabriela V. Müller, Leandro C. Sgroi, and Walter E. Baethgen
Hydrol. Earth Syst. Sci., 22, 3155–3174, https://doi.org/10.5194/hess-22-3155-2018, https://doi.org/10.5194/hess-22-3155-2018, 2018
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This study examines hydroclimate variability in northeastern Argentina; advances the understanding of its links with global SST forcing; and discusses its impacts on water resources, agriculture and human settlements. Interannual-to-multidecadal variability led to frequent extreme events. Severe floods affected agriculture, livestock productivity, and forced population displacements. Droughts affected water resources, causing water and food scarcity. Increased temperatures reduced crop yields.
Qing Cao, Zhenchun Hao, Feifei Yuan, Zhenkuan Su, Ronny Berndtsson, Jie Hao, and Tsring Nyima
Hydrol. Earth Syst. Sci., 21, 5415–5426, https://doi.org/10.5194/hess-21-5415-2017, https://doi.org/10.5194/hess-21-5415-2017, 2017
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This study analyzed the rainy-season precipitation in China influenced by various ENSO types. The precipitation anomalies were investigated under different ENSO types, which may be attributed to the combined influence of anti-cyclone in the western North Pacific and the Indian monsoon. The results improve the understanding of linkages between the precipitation and global teleconnection patterns. The results suggest a certain predictability of flood and drought related to different ENSO types.
Chia-Jeng Chen and Tsung-Yu Lee
Hydrol. Earth Syst. Sci., 21, 3463–3481, https://doi.org/10.5194/hess-21-3463-2017, https://doi.org/10.5194/hess-21-3463-2017, 2017
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Regional hydro-climatic variables are modulated by large-scale, reoccurring climate oscillations. In this article, the authors provide both statistical and physical evidence of how Taiwan’s summertime streamflow is strongly correlated with specific teleconnection patterns dominating cyclonic activity in the western North Pacific. However, such correlation can be strengthened or weakened by notable climate regime shifts, illustrating the pitfall of empirical seasonal forecasting.
Vianney Courdent, Morten Grum, Thomas Munk-Nielsen, and Peter S. Mikkelsen
Hydrol. Earth Syst. Sci., 21, 2531–2544, https://doi.org/10.5194/hess-21-2531-2017, https://doi.org/10.5194/hess-21-2531-2017, 2017
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Urban drainage and wastewater systems are heavily impacted by precipitation. Hence, weather forecasts are valuable in improving their management. However, forecasts are intrinsically uncertain, especially when fine model resolution is required, which is the case for urban hydrology. Handling uncertainty is challenging for decision makers. This study presents an economic framework to support the decision-making process by providing information on when acting on the forecast is beneficial.
Ruud J. van der Ent and Obbe A. Tuinenburg
Hydrol. Earth Syst. Sci., 21, 779–790, https://doi.org/10.5194/hess-21-779-2017, https://doi.org/10.5194/hess-21-779-2017, 2017
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This research seeks out to answer a fundamental question about the functioning of the water cycle in the atmosphere: how much time does a water particle spend in the atmosphere? Based on state-of-the-art data, we derive a global average residence time of water in the atmosphere of 8–10 days. We further show in this paper how the residence time of water varies in time and space. This serves to illustrate why it is so difficult to make weather predictions on timescales longer than a week.
Simon Parry, Robert L. Wilby, Christel Prudhomme, and Paul J. Wood
Hydrol. Earth Syst. Sci., 20, 4265–4281, https://doi.org/10.5194/hess-20-4265-2016, https://doi.org/10.5194/hess-20-4265-2016, 2016
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This paper identifies periods of recovery from drought in 52 river flow records from the UK between 1883 and 2013. The approach detects 459 events that vary in space and time. This large dataset allows individual events to be compared with others in the historical record. The ability to objectively appraise contemporary events against the historical record has not previously been possible, and may allow water managers to prepare for a range of outcomes at the end of a drought.
Lucy J. Barker, Jamie Hannaford, Andrew Chiverton, and Cecilia Svensson
Hydrol. Earth Syst. Sci., 20, 2483–2505, https://doi.org/10.5194/hess-20-2483-2016, https://doi.org/10.5194/hess-20-2483-2016, 2016
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Standardised meteorological indicators are widely used in drought monitoring, but applications to hydrological drought are less extensive. Here we assess the utility of standardised indicators for characterising drought duration, severity and propagation in a diverse set of 121 UK catchments. Spatial variations in streamflow drought characteristics reflect differences in drought propagation behaviour that are themselves largely driven by heterogeneity in catchment properties around the UK.
T. Tang, W. Li, and G. Sun
Hydrol. Earth Syst. Sci., 20, 27–37, https://doi.org/10.5194/hess-20-27-2016, https://doi.org/10.5194/hess-20-27-2016, 2016
O. Böhm, J. Jacobeit, R. Glaser, and K.-F. Wetzel
Hydrol. Earth Syst. Sci., 19, 4721–4734, https://doi.org/10.5194/hess-19-4721-2015, https://doi.org/10.5194/hess-19-4721-2015, 2015
M. Müller, M. Kašpar, A. Valeriánová, L. Crhová, E. Holtanová, and B. Gvoždíková
Hydrol. Earth Syst. Sci., 19, 4641–4652, https://doi.org/10.5194/hess-19-4641-2015, https://doi.org/10.5194/hess-19-4641-2015, 2015
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Three proposed indices combine return periods of precipitation totals or discharges with the size of the affected area. Precipitation indices also determine actual duration of either extreme or seasonally abnormal precipitation events. A unified design of the indices enables one to easily compare inter-annual and seasonal distributions of events, which is demonstrated by 50 maximum events in the Czech Republic during the period 1961-2010, including the June 2013 floods.
C. K. Folland, J. Hannaford, J. P. Bloomfield, M. Kendon, C. Svensson, B. P. Marchant, J. Prior, and E. Wallace
Hydrol. Earth Syst. Sci., 19, 2353–2375, https://doi.org/10.5194/hess-19-2353-2015, https://doi.org/10.5194/hess-19-2353-2015, 2015
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The English Lowlands is a heavily populated, water-stressed region, which is vulnerable to long droughts typically associated with dry winters. We conduct a long-term (1910-present) quantitative analysis of precipitation, flow and groundwater droughts for the region, and then review potential climatic drivers. No single driver is dominant, but we demonstrate a physical link between La Nina conditions, winter rainfall and long droughts in the region.
W. J. Shuttleworth
Hydrol. Earth Syst. Sci., 18, 4403–4406, https://doi.org/10.5194/hess-18-4403-2014, https://doi.org/10.5194/hess-18-4403-2014, 2014
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This paper explains the Matt-Shuttleworth approach clearly, simply and concisely. It shows how this approach can be implemented using a few simple equations and provides access to ancillary calculation resources that can be used for such implementation. If the crop water requirement community considered it preferable to use the Penman-Monteith equation to estimate crop water requirements directly for all crops, this could now be done using the Matt-Shuttleworth approach.
I. Masih, S. Maskey, F. E. F. Mussá, and P. Trambauer
Hydrol. Earth Syst. Sci., 18, 3635–3649, https://doi.org/10.5194/hess-18-3635-2014, https://doi.org/10.5194/hess-18-3635-2014, 2014
D. C. Verdon-Kidd and A. S. Kiem
Hydrol. Earth Syst. Sci., 18, 2257–2264, https://doi.org/10.5194/hess-18-2257-2014, https://doi.org/10.5194/hess-18-2257-2014, 2014
H. F. Goessling and C. H. Reick
Hydrol. Earth Syst. Sci., 17, 4133–4142, https://doi.org/10.5194/hess-17-4133-2013, https://doi.org/10.5194/hess-17-4133-2013, 2013
P. Brigode, Z. Mićović, P. Bernardara, E. Paquet, F. Garavaglia, J. Gailhard, and P. Ribstein
Hydrol. Earth Syst. Sci., 17, 1455–1473, https://doi.org/10.5194/hess-17-1455-2013, https://doi.org/10.5194/hess-17-1455-2013, 2013
D. Windhorst, T. Waltz, E. Timbe, H.-G. Frede, and L. Breuer
Hydrol. Earth Syst. Sci., 17, 409–419, https://doi.org/10.5194/hess-17-409-2013, https://doi.org/10.5194/hess-17-409-2013, 2013
H. Mittelbach and S. I. Seneviratne
Hydrol. Earth Syst. Sci., 16, 2169–2179, https://doi.org/10.5194/hess-16-2169-2012, https://doi.org/10.5194/hess-16-2169-2012, 2012
A. J. E. Gallant, A. S. Kiem, D. C. Verdon-Kidd, R. C. Stone, and D. J. Karoly
Hydrol. Earth Syst. Sci., 16, 2049–2068, https://doi.org/10.5194/hess-16-2049-2012, https://doi.org/10.5194/hess-16-2049-2012, 2012
B. Schaefli, R. J. van der Ent, R. Woods, and H. H. G. Savenije
Hydrol. Earth Syst. Sci., 16, 1863–1878, https://doi.org/10.5194/hess-16-1863-2012, https://doi.org/10.5194/hess-16-1863-2012, 2012
X. Han, X. Li, H. J. Hendricks Franssen, H. Vereecken, and C. Montzka
Hydrol. Earth Syst. Sci., 16, 1349–1363, https://doi.org/10.5194/hess-16-1349-2012, https://doi.org/10.5194/hess-16-1349-2012, 2012
X. Xiao, H. C. Zuo, Q. D. Yang, S. J. Wang, L. J. Wang, J. W. Chen, B. L. Chen, and B. D. Zhang
Hydrol. Earth Syst. Sci., 16, 893–910, https://doi.org/10.5194/hess-16-893-2012, https://doi.org/10.5194/hess-16-893-2012, 2012
D. Zoccatelli, M. Borga, A. Viglione, G. B. Chirico, and G. Blöschl
Hydrol. Earth Syst. Sci., 15, 3767–3783, https://doi.org/10.5194/hess-15-3767-2011, https://doi.org/10.5194/hess-15-3767-2011, 2011
G. Lenderink, H. Y. Mok, T. C. Lee, and G. J. van Oldenborgh
Hydrol. Earth Syst. Sci., 15, 3033–3041, https://doi.org/10.5194/hess-15-3033-2011, https://doi.org/10.5194/hess-15-3033-2011, 2011
J. Lorenzo-Lacruz, S. M. Vicente-Serrano, J. I. López-Moreno, J. C. González-Hidalgo, and E. Morán-Tejeda
Hydrol. Earth Syst. Sci., 15, 2581–2597, https://doi.org/10.5194/hess-15-2581-2011, https://doi.org/10.5194/hess-15-2581-2011, 2011
M. J. van den Berg, S. Vandenberghe, B. De Baets, and N. E. C. Verhoest
Hydrol. Earth Syst. Sci., 15, 1445–1457, https://doi.org/10.5194/hess-15-1445-2011, https://doi.org/10.5194/hess-15-1445-2011, 2011
A. S. Kiem and D. C. Verdon-Kidd
Hydrol. Earth Syst. Sci., 14, 433–445, https://doi.org/10.5194/hess-14-433-2010, https://doi.org/10.5194/hess-14-433-2010, 2010
J. Eliasson, O. Rögnvaldsson, and T. Jonsson
Hydrol. Earth Syst. Sci., 13, 2233–2240, https://doi.org/10.5194/hess-13-2233-2009, https://doi.org/10.5194/hess-13-2233-2009, 2009
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