ALBERT

Description: 〈b〉Watershed classification for the Canadian prairie〈/b〉〈br〉 Jared D. Wolfe, Kevin R. Shook, Chris Spence, and Colin J. Whitfield〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-625,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Watershed classification can identify regions expected to respond similarly to disturbance. Methods should extend beyond hydrology to include other environmental questions, such as ecology and water quality. We developed a classification for the Canadian Prairie, and identified seven classes defined by watershed characteristics, including elevation, climate, wetland density, and surficial geology. Results provide a basis for evaluating watershed response to land management and climate condition.

Description: 〈b〉Implications of water management representations for watershed hydrologic modeling in the Yakima River basin〈/b〉〈br〉 Jiali Qiu, Qichun Yang, Xuesong Zhang, Maoyi Huang, Jennifer C. Adam, and Keyvan Malek〈br〉 Hydrol. Earth Syst. Sci., 23, 35-49, https://doi.org/10.5194/hess-23-35-2019, 2019〈br〉 Complex water management activities challenge hydrologic modeling. We evaluated how different representations of reservoir operation and agricultural irrigation affect streamflow simulations in the Yakima River basin. Results highlight the importance of the inclusion of reliable reservoir and irrigation information in watershed models for improving watershed hydrology modeling. Models used here are public and hold the promise to benefit water assessment and management in other basins.

Description: 〈b〉Simulated single-layer forest canopies delay Northern Hemisphere snowmelt〈/b〉〈br〉 Markus Todt, Nick Rutter, Christopher G. Fletcher, and Leanne M. Wake〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-270,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 Vegetation is often represented by a single layer in global land models. Studies have found deficient simulation of thermal radiation beneath forest canopies when represented by single-layer vegetation. This study corrects thermal radiation in forests for a global land model using single-layer vegetation in order to assess the effect of deficient thermal radiation on snow cover and snowmelt. Results indicate that single-layer vegetation causes snow in forests being too cold and melting too late.

Description: 〈b〉Brief Communication: Early season snowpack loss and implications for oversnow vehicle recreation travel planning〈/b〉〈br〉 Benjamin J. Hatchett and Hilary G. Eisen〈br〉 The Cryosphere, 13, 21-28, https://doi.org/10.5194/tc-13-21-2019, 2019〈br〉 We examine the timing of early season snowpack relevant to oversnow vehicle (OSV) recreation over the past 3 decades in the Lake Tahoe region (USA). Data from two independent data sources suggest that the timing of achieving sufficient snowpack has shifted later by 2 weeks. Increasing rainfall and more dry days play a role in the later onset. Adaptation strategies are provided for winter travel management planning to address negative impacts of loss of early season snowpack for OSV usage.

Description: 〈b〉Impacts of Horizontal Resolution and Air–Sea Flux Parameterization on the Intensity and Structure of simulated Typhoon Haiyan (2013)〈/b〉〈br〉 Mien-Tze Kueh, Wen-Mei Chen, Yang-Fan Sheng, Simon C. Lin, Tso-Ren Wu, Eric Yen, Yu-Lin Tsai, and Chuan-Yao Lin〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-333,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 In this study, we show that both the model horizontal resolution and air-sea flux parameterization can exert large influence on tropical cyclone intensity simulation but with different impacts on wind structures. We highlight the intensification and contraction of TC eyewall in response to the reduction of grid spacing. We also suggest that a well-developed eyewall is more conducive to the positive effect of flux formulas on TC development.

Description: 〈b〉Develop a coupled agent-based modeling approach for uncertain water management decisions〈/b〉〈br〉 Jin-Young Hyun, Shih-Yu Huang, Y. C. Ethan Yang, Vincent Tidwell, and Jordan Macknick〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-555,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 This study applies a 〈q〉two-way〈/q〉 coupled agent-based model (ABM) with a River-Reservoir management model (RiverWare) to address the interaction between human and natural systems using Bayesian Inference (BI) mapping joined with Cost-Loss (CL). The calibration results show that this methodology can capture the historical pattern of both human activities and natural dynamics and outperforms those without using BI and CL.

Description: 〈b〉Definition differences and internal variability affect the simulated Arctic sea ice melt season〈/b〉〈br〉 Abigail Smith and Alexandra Jahn〈br〉 The Cryosphere, 13, 1-20, https://doi.org/10.5194/tc-13-1-2019, 2019〈br〉 Here we assessed how natural climate variations and different definitions impact the diagnosed and projected Arctic sea ice melt season length using model simulations. Irrespective of the definition or natural variability, the sea ice melt season is projected to lengthen, potentially by as much as 4–5 months by 2100 under the business as usual scenario. We also find that different definitions have a bigger impact on melt onset, while natural variations have a bigger impact on freeze onset.

Description: 〈b〉Greenland Ice Sheet late-season melt: Investigating multi-scale drivers of K-transect events〈/b〉〈br〉 Thomas J. Ballinger, Thomas L. Mote, Kyle Mattingly, Angela C. Bliss, Edward Hanna, Dirk van As, Melissa Prieto, Saeideh Gharehchahi, Xavier Fettweis, Brice Noël, Paul C. J. P. Smeets, Mads H. Ribergaard, and John Cappelen〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-285,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 Studies have questioned links between Arctic marginal sea open water duration and Greenland Ice Sheet (GrIS) surface balance changes, namely melt events. Through analyses involving observations and climate models, we show that late summer through autumn “unseasonal” melt events are primarily driven by the northward movement of warm, moist air masses across the western ice sheet edge, while near-surface, off-ice winds block heat transfer off nearby Baffin Bay.

Description: 〈b〉Quantitative precipitation estimation with weather radar using a data- and information-based approach〈/b〉〈br〉 Malte Neuper and Uwe Ehret〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-606,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 In our study we apply a data-driven approach to estimate precipitation quantitatively with the use of weather radar data. The method is based on Information theory concepts. It uses predictive relations expressed by empirical discrete probability distributions directly derived from data rather than the standard deterministic functions.

Description: 〈b〉Develop a coupled agent-based modeling approach for uncertain water management decisions〈/b〉〈br〉 Jin-Young Hyun, Shih-Yu Huang, Y. C. Ethan Yang, Vincent Tidwell, and Jordan Macknick〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-555,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 This study applies a 〈q〉two-way〈/q〉 coupled agent-based model (ABM) with a River-Reservoir management model (RiverWare) to address the interaction between human and natural systems using Bayesian Inference (BI) mapping joined with Cost-Loss (CL). The calibration results show that this methodology can capture the historical pattern of both human activities and natural dynamics and outperforms those without using BI and CL.

Description: 〈b〉Stochastic modeling of flow and conservative transport in three-dimensional discrete fracture networks〈/b〉〈br〉 I-Hsien Lee, Chuen-Fa Ni, Fang-Pang Lin, Chi-Ping Lin, and Chien-Chung Ke〈br〉 Hydrol. Earth Syst. Sci., 23, 19-34, https://doi.org/10.5194/hess-23-19-2019, 2019〈br〉 Few studies focused on the direct solution of the ADE for 3-D DFNs. The study is the first to solve the ADE and focus on assessing the velocity uncertainty in 3-D DFNs. The velocity uncertainty shows a limited range of influence close to the mean diameter of a fracture. The information is useful for engineering designs at sites with fractured rocks. We quantified that the tracer test in wells might lead to the overestimation of mean concentration and induce high uncertainty in fractured media.

Description: 〈b〉Time-variability of the fraction of young water in a small headwater catchment〈/b〉〈br〉 Michael P. Stockinger, Heye R. Bogena, Andreas Lücke, Christine Stumpp, and Harry Vereecken〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-604,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Precipitation moves through the soil to become streamwater. The fraction of precipitation that became streamwater after 3 months (Fyw) can be calculated with the stable isotopes of water. Previously this was done for all the isotope data available, e.g., for several years. We used one year of data to calculate Fyw and moved this calculation time window over the time series. Results highlight that Fyw varies in time. Comparison studies of different regions should take this into account.

Description: 〈b〉Distributed Temperature Profiling System Provides Spatially Dense Measurements and Insights about Permafrost Distribution in an Arctic Watershed〈/b〉〈br〉 Emmanuel Léger, Baptiste Dafflon, Yves Robert, Craig Ulrich, John E. Peterson, Sébastien Biraud, Vladimir E. Romanovsky, and Susan S. Hubbard〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-264,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 〈p〉Soil temperature has been recognized as a property that strongly influences a myriad of hydro-biogeochemical processes, as well as containing important information on the properties modulating the soil thermal flux. In spite of its importance, our ability to acquire soil temperature data with high spatial and temporal resolution and coverage is limited, because of the high cost of equipment, the difficulties of deployment, and the complexities of data management. Here we propose a new strategy that we call Distributed Temperature Profiling (DTP), which consists of cheap, low-impact, low-power, vertically resolved temperature probes that independently and autonomously record soil temperature. We developed a prototype DTP system for characterizing and monitoring near-surface thermal properties, using an unprecedented number of laterally and vertically distributed temperature measurements. The DTP system was tested in an Arctic ecosystem near Nome, AK, to identify near-surface permafrost distribution and various thermal regimes in a discontinuous permafrost environment during the summer time. Results show that the DTP system enabled successful acquisition of vertically resolved profiles of summer soil temperature over the top 0.8 m at numerous locations. DTP also enabled high resolution identification and lateral delineation of near-surface permafrost locations from surrounding zones with no permafrost or deep permafrost table locations overlain by a perennially thawed layer. The DTP strategy overcomes some of the limitations associated with – and complements the strengths of – borehole-based soil temperature sensing as well as Fiber-Optic Distributed Temperature Sensing (FO-DTS) approaches. Combining DTP data with co-located topographic and vegetation maps obtained using Unmanned Aerial Vehicle (UAV) and Electrical Resistivity Tomography (ERT) data allowed us to identify correspondences between surface and subsurface property distribution, and in particular between topography, vegetation, shallow soil properties, and near-surface permafrost. Finally, the results highlight the considerable value of the newly developed DTP strategy for investigating the significant variability and complexity of subsurface thermal and hydrological regimes in discontinuous permafrost regions.〈/p〉

Description: 〈b〉A simple model for local-scale sensible and latent heat advection contributions to snowmelt〈/b〉〈br〉 Phillip Harder, John W. Pomeroy, and Warren D. Helgason〈br〉 Hydrol. Earth Syst. Sci., 23, 1-17, https://doi.org/10.5194/hess-23-1-2019, 2019〈br〉 As snow cover becomes patchy during snowmelt, energy is advected from warm snow-free surfaces to cold snow-covered surfaces. This paper proposes a simple sensible and latent heat advection model for snowmelt situations that can be coupled to one-dimensional energy balance snowmelt models. The model demonstrates that sensible and latent heat advection fluxes can compensate for one another, especially in early melt periods.

Description: 〈b〉Quantitative precipitation estimation with weather radar using a data- and information-based approach〈/b〉〈br〉 Malte Neuper and Uwe Ehret〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-606,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 In our study we apply a data-driven approach to estimate precipitation quantitatively with the use of weather radar data. The method is based on Information theory concepts. It uses predictive relations expressed by empirical discrete probability distributions directly derived from data rather than the standard deterministic functions.

Description: 〈b〉Time-variability of the fraction of young water in a small headwater catchment〈/b〉〈br〉 Michael P. Stockinger, Heye R. Bogena, Andreas Lücke, Christine Stumpp, and Harry Vereecken〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-604,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Precipitation moves through the soil to become streamwater. The fraction of precipitation that became streamwater after 3 months (Fyw) can be calculated with the stable isotopes of water. Previously this was done for all the isotope data available, e.g., for several years. We used one year of data to calculate Fyw and moved this calculation time window over the time series. Results highlight that Fyw varies in time. Comparison studies of different regions should take this into account.

Description: 〈b〉Stochastic modeling of flow and conservative transport in three-dimensional discrete fracture networks〈/b〉〈br〉 I-Hsien Lee, Chuen-Fa Ni, Fang-Pang Lin, Chi-Ping Lin, and Chien-Chung Ke〈br〉 Hydrol. Earth Syst. Sci., 23, 19-34, https://doi.org/10.5194/hess-23-19-2019, 2019〈br〉 Few studies focused on the direct solution of the ADE for 3-D DFNs. The study is the first to solve the ADE and focus on assessing the velocity uncertainty in 3-D DFNs. The velocity uncertainty shows a limited range of influence close to the mean diameter of a fracture. The information is useful for engineering designs at sites with fractured rocks. We quantified that the tracer test in wells might lead to the overestimation of mean concentration and induce high uncertainty in fractured media.

Description: 〈b〉Spatially distributed sensitivity of simulated global groundwater heads and flows to hydraulic conductivity, groundwater recharge and surface water body parameterization〈/b〉〈br〉 Robert Reinecke, Laura Foglia, Steffen Mehl, Jonathan D. Herman, Alexander Wachholz, Tim Trautmann, and Petra Döll〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-10,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Recently, the first global groundwater models were developed to better understand surface water-groundwater interactions, and human water use impacts. However, the reliability of model outputs is limited by a lack of data as well as model assumptions required due to the necessarily coarse spatial resolution. In this study we present first global maps of model sensitivity to their parameterization and build a foundation to improve data sets and model design as well as model understanding.

Description: 〈b〉The Lituya Bay landslide-generated mega-tsunami – numerical simulation and sensitivity analysis〈/b〉〈br〉 José Manuel González-Vida, Jorge Macías, Manuel Jesús Castro, Carlos Sánchez-Linares, Marc de la Asunción, Sergio Ortega-Acosta, and Diego Arcas〈br〉 Nat. Hazards Earth Syst. Sci., 19, 369-388, https://doi.org/10.5194/nhess-19-369-2019, 2019〈br〉 In 1958, at Lituya Bay in Alaska, the largest tsunami wave ever recorded took place. Since then, its numerical simulation has been a challenge and no numerical model has been able to reproduce, in the real geometry of the bay, the more than 200 m wave and the extreme run-up (climbing of the water up on land) of 524 m. The aim of our research, in the framework of a collaboration between the University of Malága (Spain) and NOAA (US), was to fulfil this gap at the same time as verifying our model.

Description: 〈b〉Monitoring the crisis of a rock glacier with repeated UAV surveys〈/b〉〈br〉 Sebastián Vivero and Christophe Lambiel〈br〉 Geogr. Helv., 74, 59-69, https://doi.org/10.5194/gh-74-59-2019, 2019〈br〉 〈p〉In this study, rapid topographic changes and high creeping rates caused by the destabilisation of an active rock glacier in a steep mountain flank were investigated in detail with five unmanned aerial vehicle (UAV) surveys between June 2016 and September 2017. State-of-the-art photogrammetric techniques were employed to derived high-density point clouds and high-resolution orthophoto mosaics from the studied landform. The accuracy of the co-registration of subsequent point clouds was carefully examined and adjusted based on comparing stable areas outside the rock glacier, which minimised 3-D alignment errors to a mean of 0.12 m. Elevation and volumetric changes in the destabilised rock glacier were quantified over the study period. Surface kinematics were estimated with a combination of image correlation algorithms and visual inspection of the orthophoto mosaics. Between June 2016 and September 2017, the destabilised part of the rock glacier advanced up to 60–75 m and mobilised a volume of around 27 000 m〈span〉〈sup〉3〈/sup〉〈/span〉 of material which was dumped over the lower talus slope. This study has demonstrated a robust and customisable monitoring approach that allows a detailed study of rock glacier geometric changes during a crisis phase.〈/p〉

Description: 〈b〉Past and future dynamics of the Brunt Ice Shelf from seabed bathymetry and ice shelf geometry〈/b〉〈br〉 Dominic A. Hodgson, Tom A. Jordan, Jan De Rydt, Peter T. Fretwell, Samuel A. Seddon, David Becker, Kelly A. Hogan, Andrew M. Smith, and David G. Vaughan〈br〉 The Cryosphere, 13, 545-556, https://doi.org/10.5194/tc-13-545-2019, 2019〈br〉 The Brunt Ice Shelf in Antarctica is home to Halley VIa, the latest in a series of six British research stations that have occupied the ice shelf since 1956. A recent rapid growth of rifts in the Brunt Ice Shelf signals the onset of its largest calving event since records began. Here we consider whether this calving event will lead to a new steady state for the ice shelf or an unpinning from the bed, which could predispose it to accelerated flow or collapse.

Description: 〈b〉On the timescales and length scales of the Arctic sea ice thickness anomalies: a study based on 14 reanalyses〈/b〉〈br〉 Leandro Ponsoni, François Massonnet, Thierry Fichefet, Matthieu Chevallier, and David Docquier〈br〉 The Cryosphere, 13, 521-543, https://doi.org/10.5194/tc-13-521-2019, 2019〈br〉 The Arctic is a main component of the Earth's climate system. It is fundamental to understand the behavior of Arctic sea ice coverage over time and in space due to many factors, e.g., shipping lanes, the travel and tourism industry, hunting and fishing activities, mineral resource extraction, and the potential impact on the weather in midlatitude regions. In this work we use observations and results from models to understand how variations in the sea ice thickness change over time and in space.

Description: 〈b〉Reanalysis of the 1761 transatlantic tsunami〈/b〉〈br〉 Martin Wronna, Maria Ana Baptista, and Jorge Miguel Miranda〈br〉 Nat. Hazards Earth Syst. Sci., 19, 337-352, https://doi.org/10.5194/nhess-19-337-2019, 2019〈br〉 We investigate the source of the 1761 earthquake and tsunami. The reanalysis of the tsunami travel times agrees with an earlier suggested source area. We check the geodynamic setting of the area and place a fault as an extension to an identified fault and use numerical modelling to distinguish between two candidate sources. One of our theories is compatible with the geodynamic setting and reproduces well the observed tsunami parameters.

Description: 〈b〉Linear Optimal Runoff Aggregate (LORA): a global gridded synthesis runoff product〈/b〉〈br〉 Sanaa Hobeichi, Gab Abramowitz, Jason Evans, and Hylke E. Beck〈br〉 Hydrol. Earth Syst. Sci., 23, 851-870, https://doi.org/10.5194/hess-23-851-2019, 2019〈br〉 〈p〉No synthesized global gridded runoff product, derived from multiple sources, is available, despite such a product being useful for meeting the needs of many global water initiatives. We apply an optimal weighting approach to merge runoff estimates from hydrological models constrained with observational streamflow records. The weighting method is based on the ability of the models to match observed streamflow data while accounting for error covariance between the participating products. To address the lack of observed streamflow for many regions, a dissimilarity method was applied to transfer the weights of the participating products to the ungauged basins from the closest gauged basins using dissimilarity between basins in physiographic and climatic characteristics as a proxy for distance. We perform out-of-sample tests to examine the success of the dissimilarity approach, and we confirm that the weighted product performs better than its 11 constituent products in a range of metrics. Our resulting synthesized global gridded runoff product is available at monthly timescales, and includes time-variant uncertainty, for the period 1980–2012 on a 0.5〈span〉〈sup〉∘〈/sup〉〈/span〉 grid. The synthesized global gridded runoff product broadly agrees with published runoff estimates at many river basins, and represents the seasonal runoff cycle for most of the globe well. The new product, called Linear Optimal Runoff Aggregate (LORA), is a valuable synthesis of existing runoff products and will be freely available for download on 〈span〉https://geonetwork.nci.org.au/geonetwork/srv/eng/catalog.search#/metadata/f9617_9854_8096_5291〈/span〉 (last access: 31 January 2019).〈/p〉

Description: 〈b〉Multi-decadal Hydrologic Change and Variability in the Amazon River Basin: Understanding Terrestrial Water Storage Variations and Drought Characteristics〈/b〉〈br〉 Suyog Chaudhari, Yadu Pokhrel, Emilio Moran, and Gonzalo Miguez-Macho〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-57,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 〈p〉We investigate the interannual and interdecadal hydrological changes in the Amazon river basin and its sub-basins during 1980–2015 period, using GRACE satellite data and a physically-based, 2-km grid continental scale hydrological model (Leaf-Hydro-Flood) that incorporates a prognostic groundwater scheme and the effects of land use land cover change (LULC). The analyses focus on the dominant mechanisms that modulate terrestrial water storage (TWS) variations and droughts. Our results indicate that (1) the model simulates the basin-averaged TWS variations remarkably well, however, disagreements are observed in spatial patterns of temporal trends for post-2008 period, (2) the 2010s is the driest period since 1980, characterized by a major shift in decadal mean compared to 2000s due to the increased frequency of droughts, (3) long-term trends in TWS suggests that the Amazon as a whole is getting wetter (1.13 mm/y), but its southern and south-eastern sub-basins are facing significant negative TWS trends, caused primarily by intensified LULC changes, (4) increasing divergence between dry season total water deficit (TWD) and TWS release (TWS-R) suggest a strengthening dry season, especially in the southern and south-eastern sub-basins, and (5) the sub-surface storage regulates the propagation of meteorological droughts into hydrological droughts by strongly modulating TWS release with respect to its storage preceding the drought condition. Our simulations provide crucial insight on the importance of sub-surface storage in alleviating surface water deficit across Amazon and open pathways for improving prediction and mitigation of extreme droughts under changing climate and increasing hydrologic alterations due to human activities (e.g., LULC change).〈/p〉

Description: 〈b〉Toward high-spatial resolution hydrological modeling for China: Calibrating the VIC model〈/b〉〈br〉 Bowen Zhu, Xianhong Xie, Chuiyu Lu, Shanshan Meng, Yi Yao, and Yibing Wang〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-72,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 The hydrological modeling of China have been limited to spatial resolutions of 10 km or greater, rendering it impossible to assess local conditions. In our study, we developed a hydrological modeling based on VIC model at a much finer spatial scale (~ 6 km). The simulated runoff, SM and ET were extensively evaluated using observations and remote sensing data. This high-resolution modeling is capable of capturing flood and drought events with respect to their timing, duration, and spatial extent.

Description: 〈b〉Landslides Data Assimilation Using TRIGRS Based on Particle Filtering〈/b〉〈br〉 Changhu Xue, Guigen Nie, Jie Dong, Shuguang Wu, Jing Wang, Xiuzhen Li, and Xiaogang Zhang〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-16,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 This paper provides an approach to apply data assimilation method to stability analysis and parameter update and feedback in a landslide. The experiment is implemented by particle filter algorithm. The result FS sequence of TRIGRS output decreases continuously with time and the assimilation can effectively correct the FS of the model output. The RMSD of FS indicates the assimilation results can correct the estimation of TRIGRS output close to actual observations.

Description: 〈b〉Brief communication: Evaluation and inter-comparisons of Qinghai–Tibet Plateau permafrost maps based on a new inventory of field evidence〈/b〉〈br〉 Bin Cao, Tingjun Zhang, Qingbai Wu, Yu Sheng, Lin Zhao, and Defu Zou〈br〉 The Cryosphere, 13, 511-519, https://doi.org/10.5194/tc-13-511-2019, 2019〈br〉 Many maps have been produced to estimate permafrost distribution over the Qinghai–Tibet Plateau. However the evaluation and inter-comparisons of them are poorly understood due to limited in situ measurements. We provided an in situ inventory of evidence of permafrost presence or absence, with 1475 sites over the Qinghai–Tibet Plateau. Based on the in situ measurements, our evaluation results showed a wide range of map performance, and the estimated permafrost region and area are extremely large.

Description: 〈b〉Multivariate stochastic bias corrections with optimal transport〈/b〉〈br〉 Yoann Robin, Mathieu Vrac, Philippe Naveau, and Pascal Yiou〈br〉 Hydrol. Earth Syst. Sci., 23, 773-786, https://doi.org/10.5194/hess-23-773-2019, 2019〈br〉 Bias correction methods are used to calibrate climate model outputs with respect to observations. In this article, a non-stationary, multivariate and stochastic bias correction method is developed based on optimal transport, accounting for inter-site and inter-variable correlations. Optimal transport allows us to construct a joint distribution that minimizes energy spent in bias correction. Our methodology is tested on precipitation and temperatures over 12 locations in southern France.

Description: 〈b〉Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer〈/b〉〈br〉 Karina T. Meredith, Andy Baker, Martin S. Andersen, Denis M. O'Carroll, Helen Rutlidge, Liza K. McDonough, Phetdala Oudone, Eliza Bryan, and Nur Syahiza Zainuddin〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-627,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Dissolved organic carbon within groundwater and processes controlling it, remain largely unknown. Groundwater is lower compared to surface waters. The average groundwater concentration at this coastal site was five times higher than the global median, doubling with depth, but with no change in chromatographic character. The lack of oxygen limited the rate of organic matter processing leading to enhanced preservation. Changes in coastal hydrology could lead to the flux of unreacted organic carbon.

Description: 〈b〉Faulting patterns in the Lower Yarmouk Gorge potentially influence groundwater flow paths〈/b〉〈br〉 Nimrod Inbar, Eliahu Rosenthal, Fabien Magri, Marwan Alraggad, Peter Möller, Akiva Flexer, Joseph Guttman, and Christian Siebert〈br〉 Hydrol. Earth Syst. Sci., 23, 763-771, https://doi.org/10.5194/hess-23-763-2019, 2019〈br〉 In areas of enigmatic hydrology, water scarcity, and transboundary water resources, management strategies should rely on comprehensive modeling which must be based on realistic geometry, including all relevant structural features. Based on available geophysical and geological data, a new faulting pattern in the Lower Yarmouk Gorge is suggested as a basis for hydrogeological modeling. Furthermore, unexpected pull-apart basin rim fault evolution is discussed in the context of tectonic collision.

Description: 〈b〉Faulting patterns in the Lower Yarmouk Gorge potentially influence groundwater flow paths〈/b〉〈br〉 Nimrod Inbar, Eliahu Rosenthal, Fabien Magri, Marwan Alraggad, Peter Möller, Akiva Flexer, Joseph Guttman, and Christian Siebert〈br〉 Hydrol. Earth Syst. Sci., 23, 763-771, https://doi.org/10.5194/hess-23-763-2019, 2019〈br〉 In areas of enigmatic hydrology, water scarcity, and transboundary water resources, management strategies should rely on comprehensive modeling which must be based on realistic geometry, including all relevant structural features. Based on available geophysical and geological data, a new faulting pattern in the Lower Yarmouk Gorge is suggested as a basis for hydrogeological modeling. Furthermore, unexpected pull-apart basin rim fault evolution is discussed in the context of tectonic collision.

Description: 〈b〉The impact of topography on seismic amplification during the 2005 Kashmir Earthquake〈/b〉〈br〉 Saad Khan, Mark van der Meijde, Harald van der Werff, and Muhammad Shafique〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-13,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 In 2005, northern Pakistan was hit by a 7.6 magnitude earthquake. The epicenter was located near capital of the Pakistani territory of Azad Kashmir and also affected Pakistan's Khyber Pakhtunkhwa province and Indian-administered Jammu and Kashmir region. It was believed that the local topography might have significant role in direct and indirect damage in the region. This study shows that the local topography played significant role in the earthquake induced damage in the region.

Description: 〈b〉Systematic comparison of five machine-learning methods in classification and interpolation of soil particle size fractions using different transformed data〈/b〉〈br〉 Mo Zhang and Wenjiao Shi〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-584,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 1 comment)〈br〉 We systematically analyzed both direct (or indirect) soil texture classification and soil particle size fractions (psf) interpolation using five machine learning methods combined with untransformed and log ratio transformed data. The results showed that random forest had notable consequences for soil psf interpolation and soil texture classification (indirect performed better). Our systematic comparison helps to elucidate the processing and selection of compositional data in spatial simulation.

Description: 〈b〉The impact of topography on seismic amplification during the 2005 Kashmir Earthquake〈/b〉〈br〉 Saad Khan, Mark van der Meijde, Harald van der Werff, and Muhammad Shafique〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-13,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 In 2005, northern Pakistan was hit by a 7.6 magnitude earthquake. The epicenter was located near capital of the Pakistani territory of Azad Kashmir and also affected Pakistan's Khyber Pakhtunkhwa province and Indian-administered Jammu and Kashmir region. It was believed that the local topography might have significant role in direct and indirect damage in the region. This study shows that the local topography played significant role in the earthquake induced damage in the region.

Description: 〈b〉Systematic comparison of five machine-learning methods in classification and interpolation of soil particle size fractions using different transformed data〈/b〉〈br〉 Mo Zhang and Wenjiao Shi〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-584,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 1 comment)〈br〉 We systematically analyzed both direct (or indirect) soil texture classification and soil particle size fractions (psf) interpolation using five machine learning methods combined with untransformed and log ratio transformed data. The results showed that random forest had notable consequences for soil psf interpolation and soil texture classification (indirect performed better). Our systematic comparison helps to elucidate the processing and selection of compositional data in spatial simulation.

Description: 〈b〉Apparent discrepancy of Tibetan ice core δ〈sup〉18〈/sup〉O records may be attributed to misinterpretation of chronology〈/b〉〈br〉 Shugui Hou, Wangbin Zhang, Hongxi Pang, Shuangye Wu, Theo M. Jenk, and Margit Schwikowski〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-295,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 The apparent discrepancy between the Holocene δ〈sup〉18〈/sup〉O records of the Guliya and the Chongce ice cores may be attributed to a possible misinterpretation of the Guliya ice core chronology.

Description: 〈b〉Impact of assimilating sea ice concentration, sea ice thickness and snow depth in a coupled ocean–sea ice modelling system〈/b〉〈br〉 Sindre Fritzner, Rune Graversen, Kai H. Christensen, Philip Rostosky, and Keguang Wang〈br〉 The Cryosphere, 13, 491-509, https://doi.org/10.5194/tc-13-491-2019, 2019〈br〉 In this work, a coupled ocean and sea-ice ensemble-based assimilation system is used to assess the impact of different observations on the assimilation system. The focus of this study is on sea-ice observations, including the use of satellite observations of sea-ice concentration, sea-ice thickness and snow depth for assimilation. The study showed that assimilation of sea-ice thickness in addition to sea-ice concentration has a large positive impact on the coupled model.

Description: 〈b〉Hydrologic Diversity in Glacier Bay Alaska: Spatial Patterns and Temporal Change〈/b〉〈br〉 Ryan L. Crumley, David F. Hill, Jordan P. Beamer, and Elizabeth Holzenthal〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-1,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 In this study we investigate the historical (1980–2015) and forecast (2070–2099) components of freshwater runoff to Glacier Bay, Alaska using a modeling approach. We find that many of the historically snow-dominated watersheds in Glacier Bay National Park and Preserve may transition towards rainfall-dominated hydrographs in a future scenario in which CO〈sub〉2〈/sub〉 emissions are not mitigated. The changes in timing and volume of freshwater entering Glacier Bay will affect bay ecology and hydrochemistry.

Description: 〈b〉Impact of assimilating sea ice concentration, sea ice thickness and snow depth in a coupled ocean–sea ice modelling system〈/b〉〈br〉 Sindre Fritzner, Rune Graversen, Kai H. Christensen, Philip Rostosky, and Keguang Wang〈br〉 The Cryosphere, 13, 491-509, https://doi.org/10.5194/tc-13-491-2019, 2019〈br〉 In this work, a coupled ocean and sea-ice ensemble-based assimilation system is used to assess the impact of different observations on the assimilation system. The focus of this study is on sea-ice observations, including the use of satellite observations of sea-ice concentration, sea-ice thickness and snow depth for assimilation. The study showed that assimilation of sea-ice thickness in addition to sea-ice concentration has a large positive impact on the coupled model.

Description: 〈b〉Parameter-state ensemble thinning for short-term hydrological prediction〈/b〉〈br〉 Bruce Davison, Vincent Fortin, Alain Pietroniro, Man K. Yau, and Robert Leconte〈br〉 Hydrol. Earth Syst. Sci., 23, 741-762, https://doi.org/10.5194/hess-23-741-2019, 2019〈br〉 This paper explores a new method of predicting streamflow using a complex model. It makes use of streamflow observations to reduce an existing ensemble of model runs for predictive purposes. The study illustrated that the method could work given the proper constraints, which were only possible if there was enough knowledge about how the river responded to precipitation in the previous months. Ideas were discussed to allow the method to be used in a way to predict future streamflow.

Description: 〈b〉Robust uncertainty assessment of the spatio-temporal transferability of glacier mass and energy balance models〈/b〉〈br〉 Tobias Zolles, Fabien Maussion, Stephan Peter Galos, Wolfgang Gurgiser, and Lindsey Nicholson〈br〉 The Cryosphere, 13, 469-489, https://doi.org/10.5194/tc-13-469-2019, 2019〈br〉 A mass and energy balance model was subjected to sensitivity and uncertainty analysis on two different Alpine glaciers. The global sensitivity analysis allowed for a mass balance measurement independent assessment of the model sensitivity and functioned as a reduction of the model free parameter space. A novel approach of a multi-objective optimization estimates the uncertainty of the simulated mass balance and the energy fluxes. The final model uncertainty is up to 1300 kg m〈sup〉−3〈/sup〉 per year.

Description: 〈b〉The influence of wind and land evapotranspiration on the variability of moisture sources and precipitation of the Yangtze River Valley〈/b〉〈br〉 Astrid Fremme and Harald Sodemann〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-629,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 This study examines the evaporation sources of precipitation falling over the Yangtze River Valley on China's East coast. The summer monsoon rainfall causes large seasonal and interannual variations which affect a large population. We found that evaporation from surrounding land regions is important, supplying more than half of the summertime precipitation. Extreme dry and wet summers are connected to contributions from specific land and ocean regions.

Description: 〈b〉Hydrologic Diversity in Glacier Bay Alaska: Spatial Patterns and Temporal Change〈/b〉〈br〉 Ryan L. Crumley, David F. Hill, Jordan P. Beamer, and Elizabeth Holzenthal〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-1,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 In this study we investigate the historical (1980–2015) and forecast (2070–2099) components of freshwater runoff to Glacier Bay, Alaska using a modeling approach. We find that many of the historically snow-dominated watersheds in Glacier Bay National Park and Preserve may transition towards rainfall-dominated hydrographs in a future scenario in which CO〈sub〉2〈/sub〉 emissions are not mitigated. The changes in timing and volume of freshwater entering Glacier Bay will affect bay ecology and hydrochemistry.

Description: 〈b〉Robust uncertainty assessment of the spatio-temporal transferability of glacier mass and energy balance models〈/b〉〈br〉 Tobias Zolles, Fabien Maussion, Stephan Peter Galos, Wolfgang Gurgiser, and Lindsey Nicholson〈br〉 The Cryosphere, 13, 469-489, https://doi.org/10.5194/tc-13-469-2019, 2019〈br〉 A mass and energy balance model was subjected to sensitivity and uncertainty analysis on two different Alpine glaciers. The global sensitivity analysis allowed for a mass balance measurement independent assessment of the model sensitivity and functioned as a reduction of the model free parameter space. A novel approach of a multi-objective optimization estimates the uncertainty of the simulated mass balance and the energy fluxes. The final model uncertainty is up to 1300 kg m〈sup〉−3〈/sup〉 per year.

Description: 〈b〉Brief communication: Remotely piloted aircraft systems for rapid emergency response: road exposure to rockfall in Villanova di Accumoli (central Italy)〈/b〉〈br〉 Michele Santangelo, Massimiliano Alvioli, Marco Baldo, Mauro Cardinali, Daniele Giordan, Fausto Guzzetti, Ivan Marchesini, and Paola Reichenbach〈br〉 Nat. Hazards Earth Syst. Sci., 19, 325-335, https://doi.org/10.5194/nhess-19-325-2019, 2019〈br〉 The paper discusses the use of rockfall modelling software and photogrammetry applied to images acquired by RPAS to provide support to civil protection agencies during emergency response. The paper focuses on a procedure that was applied to define the residual rockfall risk for a road that was hit by an earthquake-triggered rockfall that occurred during the seismic sequence that hit central Italy on 24 August 2016. Road reopening conditions were decided based on the results of this study.

Description: 〈b〉Long-term groundwater recharge rates across India by in situ measurements〈/b〉〈br〉 Soumendra N. Bhanja, Abhijit Mukherjee, R. Rangarajan, Bridget R. Scanlon, Pragnaditya Malakar, and Shubha Verma〈br〉 Hydrol. Earth Syst. Sci., 23, 711-722, https://doi.org/10.5194/hess-23-711-2019, 2019〈br〉 Groundwater depletion in India has been a much-debated issue in recent years. Here we investigate long-term, spatiotemporal variation in prevailing groundwater recharge rates across India. Groundwater recharge rates have been estimated based on field-scale groundwater-level measurements and the tracer injection approach; recharge rates from the two estimates compared favorably. The role of precipitation in controlling groundwater recharge is studied.

Description: 〈b〉A conceptual model of organochlorine fate from a combined analysis of spatial and mid- to long-term trends of surface and ground water contamination in tropical areas (FWI)〈/b〉〈br〉 Philippe Cattan, Jean-Baptiste Charlier, Florence Clostre, Philippe Letourmy, Luc Arnaud, Julie Gresser, and Magalie Jannoyer〈br〉 Hydrol. Earth Syst. Sci., 23, 691-709, https://doi.org/10.5194/hess-23-691-2019, 2019〈br〉 We investigated the management of long-term environmental pollution by organochlorine pesticides. We selected the case of chlordecone on the island of Martinique. We propose a conceptual model of organochlorine fate accounting for physical conditions relative to soils and geology. This model explains pollution variability in water but also the dynamics of pollution trends. It helps to identify risky areas where pollution will last for a long time and where more attention is needed.

Description: 〈b〉Precipitation Transition Regions over the Southern Canadian Cordillera during January–April 2010 and under a Pseudo-Global Warming Assumption〈/b〉〈br〉 Juris D. Almonte and Ronald E. Stewart〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-48,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 〈p〉The occurrence of various types of winter precipitation is an important issue over the southern Canadian Cordillera. This issue is examined from January to April of 2010 by exploiting the high-resolution Weather Research and Forecasting (WRF) model Version 3.4.1 dataset that was used to simulate both a historical reanalysis (CTRL) and a Pseudo-Global Warming (PGW) experiment (Liu et al., 2016). Transition regions, consisting of both liquid and solid precipitation or liquid precipitation below 0 °C, occurred on 93 % and 94 % of the days in the present and PGW future, respectively. This led to accumulated precipitation within the transition region increasing by 27 % and was associated with a rise in its average elevation by 374 m over the Coast and Insular Mountains and by 240 m over the Rocky Mountains and consequently to an eastward shift towards the higher terrain of the Rocky Mountains. Transition regions comprised of only rain and snow were most common under both the CTRL and PGW simulations although all seven transition region categories occurred. Transition region changes would enhance some of the factors leading to avalanches and would also impact ski resort operations.〈/p〉

Description: 〈b〉Brief communication: Remotely piloted aircraft systems for rapid emergency response: road exposure to rockfall in Villanova di Accumoli (central Italy)〈/b〉〈br〉 Michele Santangelo, Massimiliano Alvioli, Marco Baldo, Mauro Cardinali, Daniele Giordan, Fausto Guzzetti, Ivan Marchesini, and Paola Reichenbach〈br〉 Nat. Hazards Earth Syst. Sci., 19, 325-335, https://doi.org/10.5194/nhess-19-325-2019, 2019〈br〉 The paper discusses the use of rockfall modelling software and photogrammetry applied to images acquired by RPAS to provide support to civil protection agencies during emergency response. The paper focuses on a procedure that was applied to define the residual rockfall risk for a road that was hit by an earthquake-triggered rockfall that occurred during the seismic sequence that hit central Italy on 24 August 2016. Road reopening conditions were decided based on the results of this study.

Description: 〈b〉Capturing soil-water and groundwater interactions with an iterative feedback coupling scheme: new HYDRUS package for MODFLOW〈/b〉〈br〉 Jicai Zeng, Jinzhong Yang, Yuanyuan Zha, and Liangsheng Shi〈br〉 Hydrol. Earth Syst. Sci., 23, 637-655, https://doi.org/10.5194/hess-23-637-2019, 2019〈br〉 Accurately capturing the soil-water–groundwater interaction is vital for all disciplines related to subsurface flow but is difficult when undergoing significant nonlinearity in the modeling system. A new soil-water flow package is developed to solve the switching-form Richards’ equation. A multi-scale water balance analysis joins unsaturated–saturated models at separated scales. The whole system is solved efficiently with an iterative feedback coupling scheme.

Description: 〈b〉Improving hydrological projection performance under contrasting climatic conditions using spatial coherence through a hierarchical Bayesian regression framework〈/b〉〈br〉 Zhengke Pan, Pan Liu, Shida Gao, Jun Xia, Jie Chen, and Lei Cheng〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-6,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Understanding the projection performance of hydrological models under contrasting climatic conditions supports robust decision making, which highlights the need to adopt time-varying parameters in hydrological modeling to reduce the performance degradation. This study improves our understanding of the spatial coherence of time-varying parameters, which will help improve the projection performance under differing climatic conditions.

Description: 〈b〉Study on Site Amplification Factor Correction for Earthquake Early Warning System〈/b〉〈br〉 Quancai Xie, Qiang Ma, Jingfa Zhang, and Haiying Yu〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-400,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 This paper make deep evluation of a new mthod for modelling site amplification factor. Though implement this method and make simulation for different cases, we can find that this method show better performance than the previous method and JMA Report. We will better understanding the advantage and disadvantage of this method, although there are some problems needed to consider carefully and to be solved, it shows good potential to be used in the future earthquake early waring system in the world.

Description: 〈b〉Four decades of Antarctic surface elevation changes from multi-mission satellite altimetry〈/b〉〈br〉 Ludwig Schröder, Martin Horwath, Reinhard Dietrich, Veit Helm, Michiel R. van den Broeke, and Stefan R. M. Ligtenberg〈br〉 The Cryosphere, 13, 427-449, https://doi.org/10.5194/tc-13-427-2019, 2019〈br〉 We developed an approach to combine measurements of seven satellite altimetry missions over the Antarctic Ice Sheet. Our resulting monthly grids of elevation changes between 1978 and 2017 provide unprecedented details of the long-term and interannual variation. Derived mass changes agree well with contemporaneous data of surface mass balance and satellite gravimetry and show which regions were responsible for the significant accelerations of mass loss in recent years.

Description: 〈b〉A new uncertainty estimation technique for multiple datasets and its application to various precipitation products〈/b〉〈br〉 Xudong Zhou, Jan Polcher, Tao Yang, and Ching-Sheng Huang〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-49,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 This article proposes a new uncertainty estimation technique for multiple datasets. The new uncertainty estimation method considers all the variations in time and space dimensions, so that it avoids the averaging variation in either of the dimension which is necessary in classic uncertainty estimations. Comparisons with classic and new uncertainty metrics demonstrate that classic metrics may underestimate the uncertainties among datasets.

Description: 〈b〉Characteristics of a Hailstorm over the Andean La Paz Valley〈/b〉〈br〉 Marcelo Zamuriano, Andrey Martynov, Luca Panziera, and Stefan Brönnimann〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-27,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 This work investigates the formation of a hailstorm over the Tropical Bolivian Andes. Using the WRF atmospheric model, we are able to numerically reconstruct it and we assess the main factors (mountains, lake and surface heating) in the storm formation. We propose physical mechanisms that have the potential to improve the forecasting of similar events; which are known to have a big impact over the Bolivian Altiplano, especially the region near Titicaca lake.

Description: 〈b〉Study on Site Amplification Factor Correction for Earthquake Early Warning System〈/b〉〈br〉 Quancai Xie, Qiang Ma, Jingfa Zhang, and Haiying Yu〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-400,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 This paper make deep evluation of a new mthod for modelling site amplification factor. Though implement this method and make simulation for different cases, we can find that this method show better performance than the previous method and JMA Report. We will better understanding the advantage and disadvantage of this method, although there are some problems needed to consider carefully and to be solved, it shows good potential to be used in the future earthquake early waring system in the world.

Description: 〈b〉Communicating disaster risk? An evaluation of the availability and quality of flood maps〈/b〉〈br〉 Daniel Henstra, Andrea Minano, and Jason Thistlethwaite〈br〉 Nat. Hazards Earth Syst. Sci., 19, 313-323, https://doi.org/10.5194/nhess-19-313-2019, 2019〈br〉 Flood maps can help stakeholders and the public understand their flood risk. We evaluated the quality of publicly accessible flood maps in Canadian communities designated as flood risk areas. We found that most maps (62 %) are low quality (meeting less than half of the criteria) and the highest score was 78 % (seven of nine criteria met). Canada must make a more concerted effort to produce high-quality flood maps to support its international commitment to disaster risk reduction.

Description: 〈b〉Communicating disaster risk? An evaluation of the availability and quality of flood maps〈/b〉〈br〉 Daniel Henstra, Andrea Minano, and Jason Thistlethwaite〈br〉 Nat. Hazards Earth Syst. Sci., 19, 313-323, https://doi.org/10.5194/nhess-19-313-2019, 2019〈br〉 Flood maps can help stakeholders and the public understand their flood risk. We evaluated the quality of publicly accessible flood maps in Canadian communities designated as flood risk areas. We found that most maps (62 %) are low quality (meeting less than half of the criteria) and the highest score was 78 % (seven of nine criteria met). Canada must make a more concerted effort to produce high-quality flood maps to support its international commitment to disaster risk reduction.

Description: 〈b〉More severe hydrological drought events emerge at different warming levels over the Wudinghe watershed in northern China〈/b〉〈br〉 Yang Jiao and Xing Yuan〈br〉 Hydrol. Earth Syst. Sci., 23, 621-635, https://doi.org/10.5194/hess-23-621-2019, 2019〈br〉 This paper projects future changes in drought characteristics under different warming levels over a semiarid watershed based on hydroclimate simulations. Despite large uncertainties from climate models, we find that less frequent but more severe hydrological drought events would occur in the near future, suggesting that different aspects of hydrological droughts should be carefully investigated when assessing the impact of global warming.

Description: 〈b〉Consistency of satellite-based precipitation products in space and over time compared with gauge observations and snow- hydrological modelling in the Lake Titicaca region〈/b〉〈br〉 Frédéric Satgé, Denis Ruelland, Marie-Paule Bonnet, Jorge Molina, and Ramiro Pillco〈br〉 Hydrol. Earth Syst. Sci., 23, 595-619, https://doi.org/10.5194/hess-23-595-2019, 2019〈br〉 This paper assesses the potential of satellite precipitation estimates (SPEs) for precipitation measurement and hydrological and snow modelling. A total of 12 SPEs is considered to provide a global overview of available SPE accuracy for users interested in such datasets. Results show that, over poorly monitored regions, SPEs represent a very efficient alternative to traditional precipitation gauges to follow precipitation in time and space and for hydrological and snow modelling.

Description: 〈b〉Assessment of the Greenland ice sheet–atmosphere feedbacks for the next century with a regional atmospheric model coupled to an ice sheet model〈/b〉〈br〉 Sébastien Le clec'h, Sylvie Charbit, Aurélien Quiquet, Xavier Fettweis, Christophe Dumas, Masa Kageyama, Coraline Wyard, and Catherine Ritz〈br〉 The Cryosphere, 13, 373-395, https://doi.org/10.5194/tc-13-373-2019, 2019〈br〉 Quantifying the future contribution of the Greenland ice sheet (GrIS) to sea-level rise in response to atmospheric changes is important but remains challenging. For the first time a full representation of the feedbacks between a GrIS model and a regional atmospheric model was implemented. The authors highlight the fundamental need for representing the GrIS topography change feedbacks with respect to the atmospheric component face to the strong impact on the projected sea-level rise.

Description: 〈b〉Global glacier volume projections under high-end climate change scenarios〈/b〉〈br〉 Sarah Shannon, Robin Smith, Andy Wiltshire, Tony Payne, Matthias Huss, Richard Betts, John Caesar, Aris Koutroulis, Darren Jones, and Stephan Harrison〈br〉 The Cryosphere, 13, 325-350, https://doi.org/10.5194/tc-13-325-2019, 2019〈br〉 We present global glacier volume projections for the end of this century, under a range of high-end climate change scenarios, defined as exceeding 2 °C global average warming. The ice loss contribution to sea level rise for all glaciers excluding those on the peripheral of the Antarctic ice sheet is 215.2 ± 21.3 mm. Such large ice losses will have consequences for sea level rise and for water supply in glacier-fed river systems.

Description: 〈b〉Change detection of bare-ice albedo in the Swiss Alps 〈/b〉〈br〉 Kathrin Naegeli, Matthias Huss, and Martin Hoelzle〈br〉 The Cryosphere, 13, 397-412, https://doi.org/10.5194/tc-13-397-2019, 2019〈br〉 The paper investigates the temporal changes of bare-ice glacier surface albedo in the Swiss Alps between 1999 and 2016 from a regional to local scale using satellite data. Significant negative trends were found in the lowermost elevations and margins of the ablation zones. Although significant changes of glacier ice albedo are only present over a limited area, we emphasize that albedo feedback will considerably enhance the rate of glacier mass loss in the Swiss Alps in the near future.

Description: 〈b〉Crystallographic preferred orientations of ice deformed in direct-shear experiments at low temperatures〈/b〉〈br〉 Chao Qi, David J. Prior, Lisa Craw, Sheng Fan, Maria-Gema Llorens, Albert Griera, Marianne Negrini, Paul D. Bons, and David L. Goldsby〈br〉 The Cryosphere, 13, 351-371, https://doi.org/10.5194/tc-13-351-2019, 2019〈br〉 Ice deformed in nature develops crystallographic preferred orientations, CPOs, which induce an anisotropy in ice viscosity. Shear experiments of ice revealed a transition in CPO with changing temperature/strain, which is due to the change of dominant CPO-formation mechanism: strain-induced grain boundary migration dominates at higher temperatures and lower strains, while lattice rotation dominates at other conditions. Understanding these mechanisms aids the interpretation of CPOs in natural ice.

Description: 〈b〉Assessing the characteristics and drivers of compound flooding events around the UK coast〈/b〉〈br〉 Alistair Hendry, Ivan D. Haigh, Robert J. Nicholls, Hugo Winter, Robert Neal, Thomas Wahl, Amélie Joly-Laugel, and Stephen E. Darby〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-632,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Flooding can arise from multiple sources including waves, extreme sea levels, rivers, and severe rainfall. When two or more of these sources combine, the consequences can be greatly multiplied. We find the potential for the joint occurrence of extreme sea levels and river discharge is greater on the west coast of the UK when compared to the east coast. This is due to the weather conditions generating each flood source around the UK. These results will help increase our flood forecasting ability.

Description: 〈b〉A parsimonious transport model of emerging contaminants at the river network scale〈/b〉〈br〉 Elena Diamantini, Stefano Mallucci, and Alberto Bellin〈br〉 Hydrol. Earth Syst. Sci., 23, 573-593, https://doi.org/10.5194/hess-23-573-2019, 2019〈br〉 The description of pharmaceutical fate and transport introduced into a watershed is a challenging topic, especially because of the possible adverse effects on human health. In addition, an accurate estimation of solute sources and routes is still missing. This study uses a new promising modeling approach to predict pharmaceutical concentrations in rivers. Results show an interesting relationship between solute concentrations in waters and touristic fluxes.

Description: 〈b〉Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events〈/b〉〈br〉 Andrea Rücker, Stefan Boss, James W. Kirchner, and Jana von Freyberg〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-11,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 To better understand how rain-on-snow (ROS) events affect snowpack outflow volumes and streamflow generation, we measured snowpack outflow volumes and isotopic composition during ten ROS events with automated snowmelt lysimeters at three locations in a pre-Alpine catchment. We quantified the spatiotemporal variability of snowpack outflow and its relative contribution to streamflow, and identified rainfall characteristics and initial snow depth as major controls on snow hydrological processes.

Description: 〈b〉Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events〈/b〉〈br〉 Andrea Rücker, Stefan Boss, James W. Kirchner, and Jana von Freyberg〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-11,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 To better understand how rain-on-snow (ROS) events affect snowpack outflow volumes and streamflow generation, we measured snowpack outflow volumes and isotopic composition during ten ROS events with automated snowmelt lysimeters at three locations in a pre-Alpine catchment. We quantified the spatiotemporal variability of snowpack outflow and its relative contribution to streamflow, and identified rainfall characteristics and initial snow depth as major controls on snow hydrological processes.

Description: 〈b〉Using the Maximum Entropy Production approach to integrate energy budget modeling in a hydrological model〈/b〉〈br〉 Audrey Maheu, Islem Hajji, François Anctil, Daniel F. Nadeau, and René Therrien〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-636,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 We tested a new method to simulate terrestrial evaporation in a hydrological model. Given physical constraints imposed by this model, it should help avoid the overestimation of terrestrial evaporation in climate change assessments. We show the good performance of the model by comparing simulated terrestrial evaporation to observations at three sites with different climates and vegetation. Overall, this research proposes a method that will improve our ability to make stream flow projections.

Description: 〈b〉Using the Maximum Entropy Production approach to integrate energy budget modeling in a hydrological model〈/b〉〈br〉 Audrey Maheu, Islem Hajji, François Anctil, Daniel F. Nadeau, and René Therrien〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-636,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 We tested a new method to simulate terrestrial evaporation in a hydrological model. Given physical constraints imposed by this model, it should help avoid the overestimation of terrestrial evaporation in climate change assessments. We show the good performance of the model by comparing simulated terrestrial evaporation to observations at three sites with different climates and vegetation. Overall, this research proposes a method that will improve our ability to make stream flow projections.

Description: 〈b〉Coastal vulnerability assessment: through regional to local downscaling of wave characteristics along the Bay of Lalzit (Albania)〈/b〉〈br〉 Francesco De Leo, Giovanni Besio, Guido Zolezzi, and Marco Bezzi〈br〉 Nat. Hazards Earth Syst. Sci., 19, 287-298, https://doi.org/10.5194/nhess-19-287-2019, 2019〈br〉 This paper reviews the computation of vulnerability levels (VLs) of a coast to inundation with a known model. We refer to the original proposal, detailing the VL computation through an accurate investigation of the local wave climate. We prove that the resulting vulnerability is very sensitive due to the wave features taken into account, which have to be properly assessed. The research is the follow-up of a wider project set along the Bay of Lalzit (Albania).

Description: 〈b〉From examination of natural events a proposal for risk mitigation of lahars by a cellular automata methodology: a case study for Vascún valley, Ecuador〈/b〉〈br〉 Valeria Lupiano, Francesco Chidichimo, Guillermo Machado, Paolo Catelan, Lorena Molina, Salvatore Straface, Gino M. Crisci, and Salvatore Di Gregorio〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-406,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 A method for risk mitigation of secondary lahars, triggered by violent rainfalls, is proposed as alternative to works for their containment or deviation, that could cause future disasters. It is based on the controlled generation of small lahars as a result of collapse of frail dams by backfill, forming momentary ponds as in natural cases. LLUNPIY verifies by simulation path, velocity, thickness, erosion of lahars, that could be produced; a complex case study for Vascún Valley, Ecuador is shown.

Description: 〈b〉Two-dimensional Inversion of wideband spectral data from the Capacitively Coupled Resistivity method – First Applications in periglacial environments〈/b〉〈br〉 Jan Mudler, Andreas Hördt, Anita Przyklenk, Gianluca Fiandaca, Pradip Kumar Maurya, and Christian Hauck〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-288,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 The Capacitively Coupled Resistivity method (CCR) enables the determination of frequency dependent electrical parameters of the subsurface. CCR is well suited for the application in cryospheric areas because it provides logistical advantages regarding the coupling on hard surfaces and highly resistive grounds. With our new spectral two-dimensional inversion, we can identify subsurface structures based on full spectral information. We show first results of the Inversion method on the field scale.

Description: 〈b〉Two-dimensional Inversion of wideband spectral data from the Capacitively Coupled Resistivity method – First Applications in periglacial environments〈/b〉〈br〉 Jan Mudler, Andreas Hördt, Anita Przyklenk, Gianluca Fiandaca, Pradip Kumar Maurya, and Christian Hauck〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-288,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 The Capacitively Coupled Resistivity method (CCR) enables the determination of frequency dependent electrical parameters of the subsurface. CCR is well suited for the application in cryospheric areas because it provides logistical advantages regarding the coupling on hard surfaces and highly resistive grounds. With our new spectral two-dimensional inversion, we can identify subsurface structures based on full spectral information. We show first results of the Inversion method on the field scale.

Description: 〈b〉Brief communication: Analysis of organic matter in surface snow by PTR-MS – implications for dry deposition dynamics in the Alps〈/b〉〈br〉 Dušan Materić, Elke Ludewig, Kangming Xu, Thomas Röckmann, and Rupert Holzinger〈br〉 The Cryosphere, 13, 297-307, https://doi.org/10.5194/tc-13-297-2019, 2019〈br〉 〈p〉The exchange of organic matter (OM) between the atmosphere and snow is poorly understood due to the complex nature of OM and the convoluted processes of deposition, re-volatilisation, and chemical and biological processing. OM that is finally retained in glaciers potentially holds a valuable historical record of past atmospheric conditions; however, our understanding of the processes involved is insufficient to translate the measurements into an interpretation of the past atmosphere. This study examines the dynamic processes of post-precipitation OM change at the alpine snow surface with the goal of interpreting the processes involved in surface snow OM.〈/p〉

Description: 〈b〉Modelling the Antarctic Ice Sheet across the Mid Pleistocene Transition – Implications for Oldest Ice〈/b〉〈br〉 Johannes Sutter, Hubertus Fischer, Klaus Grosfeld, Nanna B. Karlsson, Thomas Kleiner, Brice Van Liefferinge, and Olaf Eisen〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-24,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 The Antarctic Ice Sheet may have played an important role in moderating the transition between warm and cold climate epochs over the last million of years. We find that the Antarctic Ice Sheet grew considerably about 0.9 Myr ago, a time when ice age/warm age cycles changed from a 40 000 to a 100 000 yr periodicity. Our findings also suggest that ice as old as 1.5 Myr still exists at the bottom of the East Antarctic ice sheet despite the major climate reorganizations in the past.

Description: 〈b〉Simulated retreat of Jakobshavn Isbræ during the 21st century〈/b〉〈br〉 Xiaoran Guo, Liyun Zhao, Rupert Gladstone, Sainan Sun, and John C. Moore〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-7,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 〈p〉The early in the 21st century retreat of Jakobshavn Isbræ, one of Greenland's largest outlet glaciers, into its over-deepened bedrock trough was accompanied by acceleration to unprecedented ice-stream speeds. Such dramatic changes suggested the possibility of substantial mass loss over the rest of this century. Using a three-dimensional ice-sheet model with parameterizations to represent the effects of ice mélange buttressing, crevasse-depth-based calving and submarine melting, we can reproduce its recent evolution. The model can accurately replicate its inter-annual variations in grounding line and terminus position, including new modes of seasonal fluctuations that emerged after arriving at the over-deepened basin and the disappearance of a persistent floating ice shelf. The shear margin induced decreases in ice viscosity we simulate are particularly important in reproducing the large observed inter-annual changes in terminus velocity. We use this model to project Jakobshavn's evolution over this century when forced by the IPCC RCP4.5 climate scenario and simulated by ocean temperatures from 7 Earth System Models along with surface runoff derived from RACMO. In our simulations, Jakobshavn's grounding line continues to retreat ~ 18.5 km by the end of this century with total mass loss of ~ 2030 Gt (5.6 mm sea-level-rise equivalent). Despite the relative success of the model in simulating the recent behavior of the glacier, the model does not simulate winter calving events that have become relatively more important.〈/p〉

Description: 〈b〉Perspectives and ambitions of interdisciplinary connectivity researchers〈/b〉〈br〉 Eva Nora Paton, Anna Smetanová, Tobias Krueger, and Anthony Parsons〈br〉 Hydrol. Earth Syst. Sci., 23, 537-548, https://doi.org/10.5194/hess-23-537-2019, 2019〈br〉 We reviewed research perspectives and ambitions of connectivity scientists in order to improve joint connectivity research across disciplinary boundaries. We demonstrated the wide diversity of approaching science in the community. We introduced a shared mental model approach with an exploratory case study as a way to overcome persistent barriers in understanding by identifying gaps and overlaps of individual researchers' perspectives, which improves collaboration in interdisciplinary science.

Description: 〈b〉Perspectives and ambitions of interdisciplinary connectivity researchers〈/b〉〈br〉 Eva Nora Paton, Anna Smetanová, Tobias Krueger, and Anthony Parsons〈br〉 Hydrol. Earth Syst. Sci., 23, 537-548, https://doi.org/10.5194/hess-23-537-2019, 2019〈br〉 We reviewed research perspectives and ambitions of connectivity scientists in order to improve joint connectivity research across disciplinary boundaries. We demonstrated the wide diversity of approaching science in the community. We introduced a shared mental model approach with an exploratory case study as a way to overcome persistent barriers in understanding by identifying gaps and overlaps of individual researchers' perspectives, which improves collaboration in interdisciplinary science.

Description: 〈b〉Hydrogeological conceptual model of andesitic watersheds revealed by high-resolution geophysics〈/b〉〈br〉 Benoit Vittecoq, Pierre-Alexandre Reninger, Frédéric Lacquement, Guillaume Martelet, and Sophie Violette〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-637,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Water resources management on volcanic islands is challenging and faces several issues. Taking the advantage of new airborne geophysical technology, correlated with boreholes and springs data, we develop a watershed scale conceptual model and demonstrate that permeability increase with age for the studied formations. Moreover, complex geological structures lead to preferential flow circulations and to discrepancy between topographical and hydrogeological watershed, influencing rivers flowrates.

Description: 〈b〉Hydrogeological conceptual model of andesitic watersheds revealed by high-resolution geophysics〈/b〉〈br〉 Benoit Vittecoq, Pierre-Alexandre Reninger, Frédéric Lacquement, Guillaume Martelet, and Sophie Violette〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2018-637,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 Water resources management on volcanic islands is challenging and faces several issues. Taking the advantage of new airborne geophysical technology, correlated with boreholes and springs data, we develop a watershed scale conceptual model and demonstrate that permeability increase with age for the studied formations. Moreover, complex geological structures lead to preferential flow circulations and to discrepancy between topographical and hydrogeological watershed, influencing rivers flowrates.

Description: 〈b〉A method of deriving operation-specific ski run classes for avalanche risk management decisions in mechanized skiing〈/b〉〈br〉 Reto Sterchi and Pascal Haegeli〈br〉 Nat. Hazards Earth Syst. Sci., 19, 269-285, https://doi.org/10.5194/nhess-19-269-2019, 2019〈br〉 We used a revealed preference approach and identified patterns in risk management decisions of mechanized skiing operations. Our results show that terrain choices of experienced guides depend on a much broader set of factors beyond just the avalanche hazard, including skiing experience or accessibility due to weather. The identified high-resolution ski run hierarchies provide new opportunities for examining professional avalanche risk management practices and developing meaningful decision aids.

Description: 〈b〉Response time to flood events using a social vulnerability index (ReTSVI)〈/b〉〈br〉 Alvaro Hofflinger, Marcelo A. Somos-Valenzuela, and Arturo Vallejos-Romero〈br〉 Nat. Hazards Earth Syst. Sci., 19, 251-267, https://doi.org/10.5194/nhess-19-251-2019, 2019〈br〉 In this work, we propose a novel methodology (ReTSVI) to integrate a social vulnerability index into flood hazard methodologies. ReTSVI combines a series of modules that are pieces of information that interact during an evacuation, such as evacuation rate curves, mobilization, inundation models, and social vulnerability indexes, to create an integrated map of the evacuation rate in a given location.

Description: 〈b〉Comparing the efficiency of hypoxia mitigation strategies in an urban, turbid tidal river, using a coupled hydro sedimentary–biogeochemical model〈/b〉〈br〉 Katixa Lajaunie-Salla, Aldo Sottolichio, Sabine Schmidt, Xavier Litrico, Guillaume Binet, and Gwenaël Abril〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2018-381,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 〈p〉In view of future coastal hypoxia widespreading, it is essential to define management solutions to preserve a good quality of coastal ecosystems. The lower Tidal Garonne River (TGR, SW France), characterized by the seasonal presence of a turbidity maximum zone and urban water discharges, is subject to episodic hypoxia events during summer low river flow periods. The future climatic conditions (higher temperature; summer droughts) but also an increasing urbanization could enhance hypoxia risks near the city of Bordeaux in the next decades. A 3D model of dissolved oxygen (DO), which couples hydrodynamics, sediment transport and biogeochemical processes, is used to assess the efficiency of different management solutions on TGR oxygenation during summer low-discharge periods. We have runned different scenarios of reduction of urban sewage overflows, displacement of urban discharges downstream from Bordeaux, and/or temporary river flow support during summer period. The model shows that each option limits hypoxia, but with variable efficiency over time and space. Sewage overflow reduction improves DO levels only locally near the city of Bordeaux. Downstream relocation of wastewater discharges allows to reach better oxygenation level in the lower TGR. The support of low river flow limits the upstream TMZ propagation and dilutes TGR waters with well-oxygenated river waters. Scenarios combining wastewater network management and low water replenishment indicate an improvement in water quality over the entire TGR. These modelling outcomes constitute important tools for local water authorities to develop the most appropriate strategies to limit hypoxia in TGR.〈/p〉

Description: 〈b〉Development and Validation of a Dense 18-Year Time Series of Surface Water Fraction Estimates from MODIS for the Mediterranean Region〈/b〉〈br〉 Linlin Li, Andrew Skidmore, Anton Vrieling, and Tiejun Wang〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-5,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 0 comments)〈br〉 We derived an 8-day 500 m resolution surface water fraction product over the Mediterranean for 2000–2017 based on MODIS and SRTM data. Our dataset could serve as a tool for (a) monitoring the seasonal, inter-annual and long-term dynamics of surface water extent especially in arid and semi-arid areas; (b) updating and refining of existing wetland and habitat databases; and (c) evaluating ecosystem services and biodiversity assessments.

Description: 〈b〉The vertical structure of precipitation at two stations in East Antarctica derived from micro rain radars〈/b〉〈br〉 Claudio Durán-Alarcón, Brice Boudevillain, Christophe Genthon, Jacopo Grazioli, Niels Souverijns, Nicole P. M. van Lipzig, Irina V. Gorodetskaya, and Alexis Berne〈br〉 The Cryosphere, 13, 247-264, https://doi.org/10.5194/tc-13-247-2019, 2019〈br〉 Precipitation is the main input in the surface mass balance of the Antarctic ice sheet, but it is still poorly understood due to a lack of observations in this region. We analyzed the vertical structure of the precipitation using multiyear observation of vertically pointing micro rain radars (MRRs) at two stations located in East Antarctica. The use of MRRs showed the potential to study the effect of climatology and hydrometeor microphysics on the vertical structure of Antarctic precipitation.

Description: 〈b〉The vertical structure of precipitation at two stations in East Antarctica derived from micro rain radars〈/b〉〈br〉 Claudio Durán-Alarcón, Brice Boudevillain, Christophe Genthon, Jacopo Grazioli, Niels Souverijns, Nicole P. M. van Lipzig, Irina V. Gorodetskaya, and Alexis Berne〈br〉 The Cryosphere, 13, 247-264, https://doi.org/10.5194/tc-13-247-2019, 2019〈br〉 Precipitation is the main input in the surface mass balance of the Antarctic ice sheet, but it is still poorly understood due to a lack of observations in this region. We analyzed the vertical structure of the precipitation using multiyear observation of vertically pointing micro rain radars (MRRs) at two stations located in East Antarctica. The use of MRRs showed the potential to study the effect of climatology and hydrometeor microphysics on the vertical structure of Antarctic precipitation.

Description: 〈b〉Recent changes in pan-Antarctic surface snowmelt detected by AMSR-E and AMSR2〈/b〉〈br〉 Lei Zheng, Chunxia Zhou, Tingjun Zhang, Qi Liang, and Kang Wang〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-279,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 Snowmelt plays a key role in mass and energy balance in polar regions. In this study, we report on the spatial and temporal variations of the surface snowmelt over the Antarctic sea ice and ice sheet (pan-Antarctic) based on AMSR-E and AMSR2. Overall, the pan-Antarctic surface snowmelt showed a trend toward later melt onset during the 2002–2017 period. The decreasing surface snowmelt on the Antarctic ice sheet was very likely linked with the enhancing summer Southern Annular Mode.

Description: 〈b〉Water tracks intensify surface energy and mass exchange in the Antarctic McMurdo Dry Valleys〈/b〉〈br〉 Tobias Linhardt, Joseph S. Levy, and Christoph K. Thomas〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-8,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 We measured sensible, latent and soil heat fluxes along with radiation in the McMurdo Dry Valleys, Antarctica, at a water track and at predominant dry soils, serving as reference. We found a distinct impact of water tracks on surface energy and mass exchange which suggests that water tracks may serve as an indicator of change in the McMurdo Dry Valleys.

Description: 〈b〉The effect of cyclones crossing the Mediterranean region on sea level anomalies at the Mediterranean Sea coast〈/b〉〈br〉 Piero Lionello, Dario Conte, and Marco Reale〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-6,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 Large positive and negative sea level anomalies at the coast of the Mediterranean Sea are produced by cyclones moving along the Mediterranean storm track, which are mostly generated in the western Mediterranean. The wind around the cyclone center is the main cause of sea level anomalies when a shallow water fetch is present. The inverse barometer effect produces a positive anomaly near the cyclone pressure minimum and a negative anomaly at the opposite side of the Mediterranean Sea.

Description: 〈b〉The effect of cyclones crossing the Mediterranean region on sea level anomalies at the Mediterranean Sea coast〈/b〉〈br〉 Piero Lionello, Dario Conte, and Marco Reale〈br〉 Nat. Hazards Earth Syst. Sci. Discuss., https//doi.org/10.5194/nhess-2019-6,2019〈br〉 〈b〉Manuscript under review for NHESS〈/b〉 (discussion: open, 0 comments)〈br〉 Large positive and negative sea level anomalies at the coast of the Mediterranean Sea are produced by cyclones moving along the Mediterranean storm track, which are mostly generated in the western Mediterranean. The wind around the cyclone center is the main cause of sea level anomalies when a shallow water fetch is present. The inverse barometer effect produces a positive anomaly near the cyclone pressure minimum and a negative anomaly at the opposite side of the Mediterranean Sea.

Description: 〈b〉Recent changes in pan-Antarctic surface snowmelt detected by AMSR-E and AMSR2〈/b〉〈br〉 Lei Zheng, Chunxia Zhou, Tingjun Zhang, Qi Liang, and Kang Wang〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2018-279,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 Snowmelt plays a key role in mass and energy balance in polar regions. In this study, we report on the spatial and temporal variations of the surface snowmelt over the Antarctic sea ice and ice sheet (pan-Antarctic) based on AMSR-E and AMSR2. Overall, the pan-Antarctic surface snowmelt showed a trend toward later melt onset during the 2002–2017 period. The decreasing surface snowmelt on the Antarctic ice sheet was very likely linked with the enhancing summer Southern Annular Mode.

Description: 〈b〉Niger discharge from radar altimetry: Bridging gaps between gauge and altimetry time series〈/b〉〈br〉 Stefan Schröder, Anne Springer, Jürgen Kusche, Bernd Uebbing, Luciana Fenoglio-Marc, Bernd Diekkrüger, and Thomas Poméon〈br〉 Hydrol. Earth Syst. Sci. Discuss., https//doi.org/10.5194/hess-2019-36,2019〈br〉 〈b〉Manuscript under review for HESS〈/b〉 (discussion: open, 1 comment)〈br〉 We propose to derive altimetric rating curves by 〈q〉bridging〈/q〉 gaps between time series from gauge and altimeter measurements using hydrological model simulations. We investigate several stations at the Niger river, which is a challenging region. We show that altimetry reproduces discharge well and enables continuing the gauge time series, albeit at lower temporal resolution.

Description: 〈b〉Water tracks intensify surface energy and mass exchange in the Antarctic McMurdo Dry Valleys〈/b〉〈br〉 Tobias Linhardt, Joseph S. Levy, and Christoph K. Thomas〈br〉 The Cryosphere Discuss., https//doi.org/10.5194/tc-2019-8,2019〈br〉 〈b〉Manuscript under review for TC〈/b〉 (discussion: open, 0 comments)〈br〉 We measured sensible, latent and soil heat fluxes along with radiation in the McMurdo Dry Valleys, Antarctica, at a water track and at predominant dry soils, serving as reference. We found a distinct impact of water tracks on surface energy and mass exchange which suggests that water tracks may serve as an indicator of change in the McMurdo Dry Valleys.

Description: 〈b〉The selection of directional sectors for the analysis of extreme wind speed〈/b〉〈br〉 Pedro Folgueras, Sebastián Solari, and Miguel Ángel Losada〈br〉 Nat. Hazards Earth Syst. Sci., 19, 221-236, https://doi.org/10.5194/nhess-19-221-2019, 2019〈br〉 Directional effects are often relevant when studying the extreme values of natural agents, such as wind, waves, or currents. The use of a priori defined divisions is a common but subjective way to address the problem and may not fit data well in certain cases. In this work, a rational method is presented for the selection of directional sectors that, taking into account statistical indicators of the data, leads to the definition of independent and statistically homogeneous sectors.

Description: 〈b〉Delimitation of flood areas based on a calibrated a DEM and geoprocessing: case study on the Uruguay River, Itaqui, southern Brazil〈/b〉〈br〉 Paulo Victor N. Araújo, Venerando E. Amaro, Robert M. Silva, and Alexandre B. Lopes〈br〉 Nat. Hazards Earth Syst. Sci., 19, 237-250, https://doi.org/10.5194/nhess-19-237-2019, 2019〈br〉 This paper aims to map flood hazard areas under the influence of the Uruguay River, Itaqui (southern Brazil), using a calibrated digital elevation model (DEM), historic river level data and geoprocessing techniques. Assessment of the areas that can potentially be flooded can help to reduce the negative impact of flood events by supporting the process of land-use planning in areas exposed to flood hazards.

Description: 〈b〉On the nexus between landslide susceptibility and transport infrastructure – an agent-based approach〈/b〉〈br〉 Matthias Schlögl, Gerald Richter, Michael Avian, Thomas Thaler, Gerhard Heiss, Gernot Lenz, and Sven Fuchs〈br〉 Nat. Hazards Earth Syst. Sci., 19, 201-219, https://doi.org/10.5194/nhess-19-201-2019, 2019〈br〉 Landslides are destructive events, threatening the integrity of land transport systems. This paper presents how road networks are vulnerable to landslides, with emphasis on the consequences for affected road users. Results show the merits of using agent-based traffic modelling to assess the impacts of road network interruptions on rural communities by providing insights into the characteristics of the population affected and the effects on its daily routine in terms of detour costs.

Description: 〈b〉Statistical approaches for identification of low-flow drivers: temporal aspects〈/b〉〈br〉 Anne Fangmann and Uwe Haberlandt〈br〉 Hydrol. Earth Syst. Sci., 23, 447-463, https://doi.org/10.5194/hess-23-447-2019, 2019〈br〉 Low-flow events are little dynamic in space and time. Thus, it is hypothesized that models can be found, based on simple statistical relationships between low-flow metrics and meteorological states, that can help identify potential low-flow drivers. In this study we assess whether such relationships exist and whether they can be applied to predict future low flow within regional climate change impact assessment in the northwestern part of Germany.

Description: 〈b〉Integrating multiple satellite observations into a coherent dataset to monitor the full water cycle – application to the Mediterranean region〈/b〉〈br〉 Victor Pellet, Filipe Aires, Simon Munier, Diego Fernández Prieto, Gabriel Jordá, Wouter Arnoud Dorigo, Jan Polcher, and Luca Brocca〈br〉 Hydrol. Earth Syst. Sci., 23, 465-491, https://doi.org/10.5194/hess-23-465-2019, 2019〈br〉 This study is an effort for a better understanding and quantification of the water cycle and related processes in the Mediterranean region, by dealing with satellite products and their uncertainties. The aims of the paper are 3-fold: (1) developing methods with hydrological constraints to integrate all the datasets, (2) giving the full picture of the Mediterranean WC, and (3) building a model-independent database that can evaluate the numerous regional climate models (RCMs) for this region.