ALBERT

Description: Coastal dynamics and submarine permafrost in shallow water of the central Laptev Sea, East Siberia Pier Paul Overduin, Sebastian Wetterich, Frank Günther, Mikhail N. Grigoriev, Guido Grosse, Lutz Schirrmeister, Hans-Wolfgang Hubberten, and Aleksandr Makarov The Cryosphere, 10, 1449-1462, doi:10.5194/tc-10-1449-2016, 2016 How fast does permafrost warm up and thaw after it is covered by the sea? Ice-rich permafrost in the Laptev Sea, Siberia, is rapidly eroded by warm air and waves. We used a floating electrical technique to measure the depth of permafrost thaw below the sea, and compared it to 60 years of coastline retreat and permafrost depths from drilling 30 years ago. Thaw is rapid right after flooding of the land and slows over time. The depth of permafrost is related to how fast the coast retreats.

Description: Age of the Mt. Ortles ice cores, the Tyrolean Iceman and glaciation of the highest summit of South Tyrol since the Northern Hemisphere Climatic Optimum Paolo Gabrielli, Carlo Barbante, Giuliano Bertagna, Michele Bertó, Daniel Binder, Alberto Carton, Luca Carturan, Federico Cazorzi, Giulio Cozzi, Giancarlo Dalla Fontana, Mary Davis, Fabrizio De Blasi, Roberto Dinale, Gianfranco Dragà, Giuliano Dreossi, Daniela Festi, Massimo Frezzotti, Jacopo Gabrieli, Stephan Galos, Patrick Ginot, Petra Heidenwolf, Theo M. Jenk, Natalie Kehrwald, Donald Kenny, Olivier Magand, Volkmar Mair, Vladimir Mikhalenko, Ping Nan Lin, Klaus Oeggl, Gianni Piffer, Mirko Rinaldi, Ulrich Schotterer, Margit Schwikowski, Roberto Seppi, Andrea Spolaor, Barbara Stenni, Davdi Tonidandel, CChiara Uglietti, Victor Zagorodnov, Thomas Zanoner, and Piero Zennaro The Cryosphere Discuss., doi:10.5194/tc-2016-159,2016 Manuscript under review for TC (discussion: open, 0 comments) New ice cores were extracted from Alto dell'Ortles, the highest glacier of South Tyrol in the Italian Alps, to check whether prehistoric ice, that is coeval to the famous 5200 years old Tyrolean Iceman, is still preserved in this region. Dating of the ice cores confirms the hypothesis and indicates that the drilling site was glaciated since the end of the Northern Hemisphere Climatic Optimum (7000 BP). We also infer that an unprecedented acceleration of the glacier flow has just recently begun.

Description: Combined diurnal variations of discharge and hydrochemistry of the Isunnguata Sermia outlet of the Greenland Ice Sheet give in sight on sub glacial conditions Joseph Graly, Joel Harrington, and Neil Humphrey The Cryosphere Discuss., doi:10.5194/tc-2016-137,2016 Manuscript under review for TC (discussion: open, 0 comments) At a major outlet of the Greenland Ice Sheet in West Greenland, we find that the chemical solutes is the emerging subglacial waters are out of phase with water discharge and can spike in concentration during waning flow. This suggests that the subglacial waters are spreading out across a large area of the glacial bed throughout the day, stimulating chemical weathering beyond the major water distribution channels.

Description: Inversion of geothermal heat flux in a thermomechanically coupled nonlinear Stokes ice sheet model Hongyu Zhu, Noemi Petra, Georg Stadler, Tobin Isaac, Thomas J. R. Hughes, and Omar Ghattas The Cryosphere, 10, 1477-1494, doi:10.5194/tc-10-1477-2016, 2016 We study how well the basal geothermal heat flux can be inferred from surface velocity observations using a thermomechanically coupled nonlinear Stokes ice sheet model. The prospects and limitations of this inversion is studied in two and three dimensional model problems. We also argue that a one-way coupled approach for the adjoint equations motivated by staggered solvers for forward multiphysics problems can lead to an incorrect gradient and premature termination of the optimization iteration.

Description: Increased nitrate and decreased δ 15 N–NO 3 − in the Greenland Arctic after 1940 attributed to North American oil burning Nathan J. Chellman, Meredith G. Hastings, and Joseph R. McConnell The Cryosphere Discuss., doi:10.5194/tc-2016-163,2016 Manuscript under review for TC (discussion: open, 0 comments) This manuscript analyzes the changing sources of nitrate deposition to Greenland since 1760 CE using a dataset consisting of sub-seasonally resolved nitrogen isotopes of nitrate and source tracers. Correlations amongst ion concentration, source tracers, and the δ 15 N–NO 3 − provide evidence of the impact of biomass burning and fossil fuel combustion emissions of nitrogen oxides and suggest that oil combustion is the likely driver of increased nitrate concentration in Greenland ice since 1940 CE.

Description: Slight glacier reduction over the northwestern Tibetan Plateau despite significant recent warming Yetang Wang, Shugui Hou, Wenling An, Hongxi Pang, and Yaping Liu The Cryosphere Discuss., doi:10.5194/tc-2016-165,2016 Manuscript under review for TC (discussion: open, 0 comments) This study further confirms "Pamir–Karakoram–Western-Kunlun-Mountain (northwestern Tibetan Plateau) Glacier Anomaly". Slight glacier reduction over the northwestern Tibetan Plateau may result from more accumulation from increased precipitation in winter which to great extent protects it from mass reductions under climate warming during 1961–2000. Warming slowdown since 2000 happening at this region may further mitigate glacier mass reduction.

Description: Response of seasonal soil freeze depth to climate change across China Xiaoqing Peng, Oliver W. Frauenfeld, Tingjun Zhang, Kang Wang, Bin Cao, Xinyue Zhong, Hang Su, and Cuicui Mu The Cryosphere Discuss., doi:10.5194/tc-2016-129,2016 Manuscript under review for TC (discussion: open, 0 comments) Previous researches paid more attention on the permafrost, e.g. active layer thickness, soil temperature, permafrost area extent, and associated with permafrost degradation leading other changes. However, seasonally frozen ground, vast area extent, did not focus by so much attention. Here, we combined more than 800 observation station data and gridded data to investigate soil freeze depth across China. The results indicate that soil freeze depth increase with climate warming.

Description: Characteristics of an avalanche-feeding and partially debris-covered glacier and its response to atmospheric warming in Mt. Tomor, Tian Shan, China Puyu Wang, Zhongqin Li, and Huilin Li The Cryosphere Discuss., doi:10.5194/tc-2016-138,2016 Manuscript under review for TC (discussion: open, 0 comments) A cirque-valley glacier with complex topography and partially debris-covered area was investigated in the Mt. Tomor, Tian Shan. The glacier is analogous to temperate one on movement and temperature regimes. The strongest ablation and most significant terminus retreat and area reduction occurred at the end of last century and the beginning of this century. Since inhibition of debris cover to melting, it is expected to keep shrinkage in the coming decades, but the terminus retreat is to be slower.

Description: Development of high-resolution multi-scale modelling system for simulation of coastal-fluvial urban flooding Agnieszka Indiana Olbert, Joanne Comer, Stephen Nash, and Michael Hartnett Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-238,2016 Manuscript under review for NHESS (discussion: open, 0 comments) A novel nested flood model (MSN_Flood) is applied to simulate complex coastal-fluvial urban flooding in order to critically examine the model's capability to forecast evolution of urban inundation. The model demonstrates high accuracy of outputs without incurring the computational expense of high spatial resolution over the entire model domain. MSN_Flood provides full characteristics of water levels and flow regimes necessary for flood hazard identification and flood risk assessment.

Description: Comparison and validation of global and regional ocean forecasting systems for the South China Sea Xueming Zhu, Hui Wang, Guimei Liu, Charly Régnier, Xiaodi Kuang, Dakui Wang, Shihe Ren, Zhiyou Jing, and Marie Drévillon Nat. Hazards Earth Syst. Sci., 16, 1639-1655, doi:10.5194/nhess-16-1639-2016, 2016 This paper examined the performances of two operational ocean forecasting systems, Mercator Océan in France and SCSOFS in China, based on observed satellite and in situ data obtained in 2012. The comparison and validation are focused on the ocean circulations, the structures of temperature and salinity, and some mesoscale activities in the South China Sea. Finally, some recommendations have been proposed for both systems to improve their performances in the near future.

Description: An ice-sheet-wide framework for englacial attenuation from ice-penetrating radar data T. M. Jordan, J. L. Bamber, C. N. Williams, J. D. Paden, M. J. Siegert, P. Huybrechts, O. Gagliardini, and F. Gillet-Chaulet The Cryosphere, 10, 1547-1570, doi:10.5194/tc-10-1547-2016, 2016 Ice penetrating radar enables determination of the basal properties of ice sheets. Existing algorithms assume stationarity in the attenuation rate, which is not justifiable at an ice sheet scale. We introduce the first ice-sheet-wide algorithm for radar attenuation that incorporates spatial variability, using the temperature field from a numerical model as an initial guess. The study is a step toward ice-sheet-wide data products for basal properties and evaluation of model temperature fields.

Description: Circumpolar polynya regions and ice production in the Arctic: Results from MODIS thermal infrared imagery for 2002/2003 to 2014/2015 with a regional focus on the Laptev Sea Andreas Preußer, Günther Heinemann, Sascha Willmes, and Stephan Paul The Cryosphere Discuss., doi:10.5194/tc-2016-133,2016 Manuscript under review for TC (discussion: open, 0 comments) Our study presents spatial and temporal characteristics of 16 prominent polynya regions over the entire Arctic basin. By using an energy balance model, we are able to derive daily thin-ice thickness distributions from satellite and atmospheric reanalysis data. All polynyas combined yield an average ice production of about 1444 km 3 per winter. Interestingly, we find distinct regional differences in calculated trends over the last 13 years. Finally, we set a special focus on the Laptev Sea region.

Description: Statistical indicators of Arctic sea-ice stability – prospects and limitations Sebastian Bathiany, Bregje van der Bolt, Mark S. Williamson, Timothy M. Lenton, Marten Scheffer, Egbert H. van Nes, and Dirk Notz The Cryosphere, 10, 1631-1645, doi:10.5194/tc-10-1631-2016, 2016 We examine if a potential "tipping point" in Arctic sea ice, causing abrupt and irreversible sea-ice loss, could be foreseen with statistical early warning signals. We assess this idea by using several models of different complexity. We find robust and consistent trends in variability that are not specific to the existence of a tipping point. While this makes an early warning impossible, it allows to estimate sea-ice variability from only short observational records or reconstructions.

Description: Enhancing local action planning through quantitative flood risk analysis: a case study in Spain Jesica Tamara Castillo-Rodríguez, Ignacio Escuder-Bueno, Sara Perales-Momparler, and Juan Ramón Porta-Sancho Nat. Hazards Earth Syst. Sci., 16, 1699-1718, doi:10.5194/nhess-16-1699-2016, 2016 This article presents a method to incorporate and promote quantitative flood risk analysis to support local action planning against flooding. The conducted research work aims at providing a framework for local flood risk analysis and to support risk-informed decision-making (e.g. urban planning and development, flood risk management, civil protection). This article shows the added value of a risk-informed perspective, applied to a real case study in Spain.

Description: Meteorological factors driven glacial till changing and the associated periglacial debris flows in Tianmo Valley, southeast Tibetan Plateau Mingfeng Deng, Ningsheng Chen, and Mei Liu Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-251,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Initiation of deris flows in Tianmo valley shows annual temperature spiked and glacier retreat quickly before the three debris flows, while they did not occur when glacier retreat is sharpest, resulting from the bared glacial till is frozen as the melting of internal ice lags behind glacial retreat. The activity of the glacial till can be enhanced by prolonged high air temperature. Finally, either rainfall or continuous percolation of ice ablation water flows can generate periglacial debris flows.

Description: Analysis of slope processes in the Vallcebre landslide (Eastern Pyrenees, Spain) by means of Cross Correlation Function applied to high frequency monitoring data Marco Mulas, Jordi Corominas, Alessandro Corsini, and Jose Moya Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-253,2016 Manuscript under review for NHESS (discussion: open, 0 comments) In this work, the Cross-Correlation Function is used in order to quantitatively investigate the time-lagged correlation between high frequency monitoring data on rainfall, piezometric and displacement with the objective to evidence hydro-mechanical processes in the Vallcebre landslide (Eastern Pyrenees, Spain). The analysis highlighted and constrained in time a dual triggering mechanism in which factors controlling movement change from the upper to the lower part of the landslide.

Description: Signature of Arctic first-year ice melt pond fraction in X-band SAR imagery Ane S. Fors, Dmitry V. Divine, Anthony P. Doulgeris, Angelika H. H. Renner, and Sebastian Gerland The Cryosphere Discuss., doi:10.5194/tc-2016-125,2016 Manuscript under review for TC (discussion: open, 0 comments) This paper investigates the signature of melt ponds in satellite borne synthetic aperture radar (SAR) imagery. The study shows that polarimetric X-band SAR can be used to extract melt pond fraction from drifting first-year sea ice, and discusses the influence of factors like wind speed, SAR incidence angle and instrument noise floor. Melt ponds strongly influence the Arctic sea ice energy budget, and the results imply prospective opportunities for expanded monitoring of melt ponds from space.

Description: Greenland annual accumulation along the EGIG line, 1959–2004, from ASIRAS airborne radar and neutron-probe density measurements Thomas B. Overly, Robert L. Hawley, Veit Helm, Elizabeth M. Morris, and Rohan N. Chaudhary The Cryosphere, 10, 1679-1694, doi:10.5194/tc-10-1679-2016, 2016 We demonstrate that snow accumulation rates across the Greenland Ice Sheet, determined from RADAR layers and modeled snow density profiles, are identical to ground-based measurements of snow accumulation. Three regional climate models underestimate snow accumulation compared to RADAR layer estimates. Using RADAR increases spatial coverage and improves accuracy of snow accumulation estimates. Incorporating our results into climate models may reduce uncertainty of sea-level rise estimates.

Description: Vulnerability curves vs. vulnerability indicators: application of an indicator-based methodology for debris-flow hazards Maria Papathoma-Köhle Nat. Hazards Earth Syst. Sci., 16, 1771-1790, doi:10.5194/nhess-16-1771-2016, 2016 Two established methods for assessing the physical vulnerability of buildings to natural hazards (vulnerability indicators and vulnerability curves) are compared after beind applied at the same case study. The case study area is located in South Tyrol (Italy) and it is subject to debris flow hazard. The results indicate that both methods have advantages and disadvantages and should be used in combination rather than in isolation by practitioners.

Description: What if the 25 October 2011 event that struck Cinque Terre (Liguria) had happened in Genoa, Italy? Flooding scenarios, hazard mapping and damage estimation Francesco Silvestro, Nicola Rebora, Lauro Rossi, Daniele Dolia, Simone Gabellani, Flavio Pignone, Eva Trasforini, Roberto Rudari, Silvia De Angeli, and Cristiano Masciulli Nat. Hazards Earth Syst. Sci., 16, 1737-1753, doi:10.5194/nhess-16-1737-2016, 2016 During the autumn of 2011 two catastrophic, very intense rainfall events affected two different parts of the Liguria Region of Italy causing various flash floods. The first occurred in October and the second at the beginning of November. Both the events were characterized by very high rainfall intensities (〉 100 mm h −1 ) that persisted on a small portion of territory causing local huge rainfall accumulations (〉 400 mm 6 h −1 ). Two main considerations were made in order to set up this work. The first consideration is that various studies demonstrated that the two events had a similar genesis and similar triggering elements. The second very evident and coarse concern is that two main elements are needed to have a flash flood: a very intense and localized rainfall event and a catchment (or a group of catchments) to be affected. Starting from these assumptions we did the exercise of mixing the two flash flood ingredients by putting the rainfall field of the first event on the main catchment struck by the second event, which has its mouth in the biggest city of the Liguria Region: Genoa. A complete framework was set up to quantitatively carry out a “what if” experiment with the aim of evaluating the possible damages associated with this event. A probabilistic rainfall downscaling model was used to generate possible rainfall scenarios maintaining the main characteristics of the observed rainfall fields while a hydrological model transformed these rainfall scenarios in streamflow scenarios. A subset of streamflow scenarios is then used as input to a 2-D hydraulic model to estimate the hazard maps, and finally a proper methodology is applied for damage estimation. This leads to the estimation of the potential economic losses and of the risk level for the people that stay in the affected area. The results are interesting, surprising and in a way worrying: a rare but not impossible event (it occurred about 50 km away from Genoa) would have caused huge damages estimated between 120 and EUR 230 million for the affected part of the city of Genoa, Italy, and more than 17 000 potentially affected people.

Description: VISIR: technological infrastructure of an operational service for safe and efficient navigation in the Mediterranean Sea Gianandrea Mannarini, Giuseppe Turrisi, Alessandro D'Anca, Mario Scalas, Nadia Pinardi, Giovanni Coppini, Francesco Palermo, Ivano Carluccio, Matteo Scuro, Sergio Cretì, Rita Lecci, Paola Nassisi, and Luca Tedesco Nat. Hazards Earth Syst. Sci., 16, 1791-1806, doi:10.5194/nhess-16-1791-2016, 2016 Safety and efficiency of navigation can be enhanced through a better situational awareness at sea. We designed and realized an operational infrastructure for providing the navigators with optimal routes through various devices: PC, tablets, and smartphones. Sea-state and wind forecasts are used as inputs. Both motor- and sailboat routes are addressed by VISIR.

Description: Thermal impacts of engineering activities and vegetation layer on permafrost in different alpine ecosystems of the Qinghai–Tibet Plateau, China Qingbai Wu, Zhongqiong Zhang, Siru Gao, and Wei Ma The Cryosphere, 10, 1695-1706, doi:10.5194/tc-10-1695-2016, 2016 Climate warming and engineering activities have various impacts on the thermal regime of permafrost in alpine ecosystems of the Qinghai–Tibet Plateau. Using recent observations of permafrost thermal regimes along the Qinghai–Tibet highway and railway, the changes of such regimes beneath embankments constructed in alpine meadows and steppes are studied. The results show that alpine meadows on the Qinghai–Tibet Plateau can have a controlling role among engineering construction effects on permafrost beneath embankments. As before railway construction, the artificial permafrost table (APT) beneath embankments is not only affected by climate change and engineering activities but is also controlled by alpine ecosystems. However, the change rate of APT is not dependent on ecosystem type, which is predominantly affected by climate change and engineering activities. Instead, the rate is mainly related to cooling effects of railway ballast and heat absorption effects of asphalt pavement. No large difference between alpine and steppe can be identified regarding the variation of soil temperature beneath embankments, but this difference is readily identified in the variation of mean annual soil temperature with depth. The vegetation layer in alpine meadows has an insulation role among engineering activity effects on permafrost beneath embankments, but this insulation gradually disappears because the layer decays and compresses over time. On the whole, this layer is advantageous for alleviating permafrost temperature rise in the short term, but its effect gradually weakens in the long term.

Description: Impact of Icebergs on Net Primary Productivity in the Southern Ocean Shuang-Ye Wu and Shugui Hou The Cryosphere Discuss., doi:10.5194/tc-2016-166,2016 Manuscript under review for TC (discussion: open, 0 comments) The primary productivity in the Southern Ocean (SO) is limited by the amount of iron available for biological activities. Recent studies show that icebergs could be a main source of iron to the SO. Based on remote sensing data, our study shows that iceberg presence has a small, yet statistically significant, positive impact on productivity. As iceberg quantity increases, their positive influence on productivity also increases. This impact could serve as a negative feedback to the climate system.

Description: Possible groundwater dominance in the subglacial hydrology of ice sheet interiors: example at Dome C, East Antarctica Brad T. Gooch, Sasha P. Carter, Omar Ghattas, Duncan A. Young, and Donald D. Blankenship The Cryosphere Discuss., doi:10.5194/tc-2016-141,2016 Manuscript under review for TC (discussion: open, 0 comments) Our work investigates the potential significance of groundwater flow underneath the interior of East Antarctica where the ice doesn't rapidly melt. We attempt to describe the relationship between two hydrologic systems (water under the ice and in the ground) and how they might interact along a flow path between lakes under the ice. We find that groundwater is significant in regional water transport for melt water under the ice in areas of low melting in East Antarctica.

Description: Design of a scanning laser meter for monitoring the spatio-temporal evolution of snow depth and its application in the Alps and in Antarctica Ghislain Picard, Laurent Arnaud, Jean-Michel Panel, and Samuel Morin The Cryosphere, 10, 1495-1511, doi:10.5194/tc-10-1495-2016, 2016 A cost-effective automatic laser scan has been built to measure snow depth spatio-temporal variations. Deployed in the Alps and in Dome C (Antarctica), two devices acquired daily scans covering a surface area of 100–150 m 2 . The precision and long-term stability of the measurements are about 1 cm and the accuracy is better than 5 cm. These high performances are particularly suited at Dome C, where it was possible to reveal that most of the accumulation in the year 2015 stems from a single event.

Description: Brief Communication: An update of the article "Modelling flood damages under climate change conditions – a case study for Germany" Fred Fokko Hattermann, Shaochun Huang, Olaf Burghoff, Peter Hoffmann, and Zbigniew W. Kundzewicz Nat. Hazards Earth Syst. Sci., 16, 1617-1622, doi:10.5194/nhess-16-1617-2016, 2016 We report that a considerable increase in flood-related losses can be expected in Germany in a future warmer climate. The general significance of the study is supported by the fact that the outcome of an ensemble of global climate models (GCMs) and regional climate models (RCMs) was used as a climate driver for a hydrological model considering more than 3000 river basins in Germany.

Description: Arctic sea-ice diffusion from observed and simulated Lagrangian trajectories Pierre Rampal, Sylvain Bouillon, Jon Bergh, and Einar Ólason The Cryosphere, 10, 1513-1527, doi:10.5194/tc-10-1513-2016, 2016 Due to the increasing activity in Arctic, sea-ice–ocean models are now frequently used to produce operational forecasts, for oil spill trajectory modelling and to assist in offshore operations planning. In this study we evaluate the performance of two models with respect to their capability to reproduce observed sea ice diffusion properties by using metrics based on Lagrangian statistics. This paper presents a new and useful evaluation metric for current coupled sea ice–ocean models.

Description: Retrieval of the thickness of undeformed sea ice from simulated C-band compact polarimetric SAR images Xi Zhang, Wolfgang Dierking, Jie Zhang, Junmin Meng, and Haitao Lang The Cryosphere, 10, 1529-1545, doi:10.5194/tc-10-1529-2016, 2016 In this work, we introduced a parameter ("CP ratio") for the retrieval of the thickness of undeformed first-year sea ice that is specifically adapted to compact polarimetric SAR images. Based on a validation using other compact polarimetric SAR images from the Labrador Sea, we found a root mean square error of 8 cm and a maximum correlation coefficient of 0.94 for the retrieval procedure when applying it to level ice between 0.1 m and 0.8 m thick.

Description: Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts Hiroshi Takagi, Takahito Mikami, Daisuke Fujii, Miguel Esteban, and Shota Kurobe Nat. Hazards Earth Syst. Sci., 16, 1629-1638, doi:10.5194/nhess-16-1629-2016, 2016 Thin coastal dykes found in developing countries may suddenly collapse due to land subsidence, material ageing, earthquakes, a collision with vessels, etc. Such a failure could trigger a dyke-break-induced tsunami. To analyse the potential consequences of such a flooding event, a hydrodynamic model was created using the data from the authors' field surveys of a vulnerable coastal community in Jakarta. The countermeasure of using mangrove forest is also proposed to mitigate violent floods.

Description: High resolution boundary conditions of an old ice target near Dome C, Antarctica Duncan A. Young, Jason L. Roberts, Catherine Ritz, Massimo Frezzotti, Enrica Quartini, Marie G. P. Cavitte, Carly R. Tozer, Daniel Steinhage, Stefano Urbini, Hugh F. J. Corr, Tas Van Ommen, and Donald D. Blankenship The Cryosphere Discuss., doi:10.5194/tc-2016-169,2016 Manuscript under review for TC (discussion: open, 0 comments) Glacial ice can preserve records of Earth's ancient atmosphere (including greenhouse gases) that can be compared to ocean sediment records of ice sheet size to better understand climate feedbacks. To find records of the greenhouse gases found in key periods of climate transition, we need to find sites of unmelted old ice near the base of the ice sheet. We performed a high resolution survey of such a site near Europe's Concordia station in East Antarctica, using a multi instrument aircraft.

Description: Debris flow impact estimation on a rigid barrier Federico Vagnon and Andrea Segalini Nat. Hazards Earth Syst. Sci., 16, 1691-1697, doi:10.5194/nhess-16-1691-2016, 2016 This study has the aim of reviewing the dynamics of debris flow impact against rigid structures and providing a new simple formulation to predict peak thrust. The proposed equation differs from other formulations because it takes into account flow characteristics, material properties, and barrier dimensions. The developed model is sufficiently capable of predicting measured force during the laboratory tests.

Description: Using video games for volcanic hazard education and communication: an assessment of the method and preliminary results Lara Mani, Paul D. Cole, and Iain Stewart Nat. Hazards Earth Syst. Sci., 16, 1673-1689, doi:10.5194/nhess-16-1673-2016, 2016 Here, we aim to better understand the potential for using video games in volcanic hazard education with at-risk communities. A study using a bespoke-designed video game – St. Vincent's Volcano – was trialled on the Caribbean island of St. Vincent in 2015. Preliminary data analysis demonstrates 94 % of study participants had an improved knowledge of volcanic hazards after playing the game, leading us to conclude that video games could be a logical progression for education and outreach activities.

Description: Snowpack modelling in the Pyrenees driven by kilometric-resolution meteorological forecasts Louis Quéno, Vincent Vionnet, Ingrid Dombrowski-Etchevers, Matthieu Lafaysse, Marie Dumont, and Fatima Karbou The Cryosphere, 10, 1571-1589, doi:10.5194/tc-10-1571-2016, 2016 Simulations are carried out in the Pyrenees with the snowpack model Crocus, driven by meteorological forecasts from the model AROME at kilometer resolution. The evaluation is done with ground-based measurements, satellite data and reference simulations. Studying daily snow depth variations allows to separate different physical processes affecting the snowpack. We show the benefits of AROME kilometric resolution and dynamical behavior in terms of snowpack spatial variability in a mountain range.

Description: Radiocarbon dating of glacier ice Chiara Uglietti, Alexander Zapf, Theo M. Jenk, Sönke Szidat, Gary Salazar, and Margit Schwikowski The Cryosphere Discuss., doi:10.5194/tc-2016-160,2016 Manuscript under review for TC (discussion: open, 0 comments) A meaningful interpretation of the climatic history contained in ice cores requires a precise chronology. For dating the older and deeper part of the glaciers, radiocarbon analysis can be used, when organic matter such as plant or insect fragments is found in the ice. Since this happens rarely, a complementary dating tool is based on radiocarbon dating of the insoluble fraction of carbonaceous aerosols entrapped in the ice, allowing dating ice with ages between 200 and more than 10 000 years.

Description: Effects of stratified active layers on high-altitude permafrost warming: a case study on the Qinghai–Tibet Plateau Xicai Pan, Yanping Li, Qihao Yu, Xiaogang Shi, Daqing Yang, and Kurt Roth The Cryosphere, 10, 1591-1603, doi:10.5194/tc-10-1591-2016, 2016 Using a 9-year dataset in conjunction with a process-based model, we verify that the common assumption of a considerably smaller thermal conductivity in the thawed season than the frozen season is not valid at a site with a stratified active layer on the Qinghai–Tibet Plateau (QTP). The unique hydraulic and thermal mechanism in the active layer challenges the concept of thermal offset used in conceptual permafrost models and hints at the reason for rapid permafrost warming on the QTP.

Description: Brief communication: Organochlorine pesticides in an archived firn core from Law Dome, East Antarctica Marie Bigot, Mark A. J. Curran, Andrew D. Moy, Derek C. G. Muir, Darryl W. Hawker, Roger Cropp, Camilla F. Teixeira, and Susan Bengtson Nash The Cryosphere Discuss., doi:10.5194/tc-2016-178,2016 Manuscript under review for TC (discussion: open, 0 comments) Organochlorine pesticides (OCPs) were, for the first time, quantified in archived firn cores from the East Antarctic ice sheet representative of 1945–1957 C.E. and 1958–1967 C.E. The core sections were melted under high purity nitrogen atmosphere and the melt water analysed. Methods allowed quantification of hexachlorocyclohexanes, heptachlor, trans-chlordane, dieldrin and endrin. While the core presented evidence of nominal modern-use chemical contamination, indicating handling and/or storage contamination, legacy OCP concentrations and deposition rates reported are orders of magnitude lower than those from Arctic regions, lending support for their validity. The study further provides a description of equipment used and suggests adapted methods to overcome logistical challenges associated with trace organic contaminant detection in Polar Regions.

Description: Simple and approximate upper-limit estimation of future precipitation return-values Rasmus E. Benestad, Kajsa M. Parding, Abdelkader Mezghani, and Anita V. Dyrrdal Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-229,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We propose a strategy for quantifying the maximum effect a temperature change has on heavy precipitation amounts making use of the limited available sources of information: laws of physics, seasonal variations, mathematical estimation of probability, and large number of climate model results. An upper bound is estimated rather than most likely value.

Description: Connected subglacial lake drainage beneath Thwaites Glacier, West Antarctica Benjamin E. Smith, Noel Gourmelen, Alexander Huth, and Ian Joughin The Cryosphere Discuss., doi:10.5194/tc-2016-180,2016 Manuscript under review for TC (discussion: open, 0 comments) In this paper we investigate elevation changes of Thwaites Glacier, West Antarctica, one of the main sources of excess ice discharge into the ocean. We find that in early 2013, four subglacial lakes separated by 100 km drained suddenly, discharging more than three cubic kilometers of water under the fastest part of the glacier in less than six months. Concurrent ice-speed measurements show only minor changes, suggesting that ice dynamics are not strongly sensitive to changes in water flow.

Description: Isotopic exchange on the diurnal scale between near-surface snow and lower atmospheric water vapor at Kohnen station, East Antarctica François Ritter, Hans Christian Steen-Larsen, Martin Werner, Valérie Masson-Delmotte, Anais Orsi, Melanie Behrens, Gerit Birnbaum, Johannes Freitag, Camille Risi, and Sepp Kipfstuhl The Cryosphere, 10, 1647-1663, doi:10.5194/tc-10-1647-2016, 2016 We present the first successful continuous measurements of water vapor isotopes performed in Antarctica in January 2013. The interest is to understand the impact of the water vapor isotopic composition on the near-surface snow isotopes. Our study reveals a diurnal cycle in the snow isotopic composition in phase with the vapor. This finding suggests fractionation during the sublimation of the ice, which has an important consequence on the interpretation of water isotope variations in ice cores.

Description: Partial reactivation of a huge deep-seated ancient rock slide: recognition, formation mechanism, and stability Minggao Tang, Qiang Xu, Yusheng Li, Runqiu Huang, Niek Rengers, and Xing Zhu Nat. Hazards Earth Syst. Sci., 16, 1719-1735, doi:10.5194/nhess-16-1719-2016, 2016 An important argument for the conclusion is the recognition of a regional compressive tectonic stress field in this area, which cannot lead to the formation of a fault graben, which needs a tensional tectonic stress field. Moreover, numerous unique geological features, sliding marks, and other relics of the ancient slide have been discovered in the field. A centrifuge model test shows that a deformation and failure process of "creep–crack–cut" and a type of "successive rotational rock slide" have occurred.

Description: Evaposublimation from the snow in the Mediterranean mountains of Sierra Nevada (Spain) Javier Herrero and María José Polo The Cryosphere Discuss., doi:10.5194/tc-2016-161,2016 Manuscript under review for TC (discussion: open, 0 comments) This manuscript presents 7 years of field work and modelling to assess the importance of the loss of water from the snow by means of sublimation in the Mediterranean mountains of Sierra Nevada. The actual sublimation rates were detected through detailed measurement of the mass fluxes from the snow. These data have led to some improvements in the modelling of the snow in this kind of mountainous semiarid regions. The sublimation is estimated to range between 24–33 % of total annual snowfall.

Description: An automated methodology for differentiating rock from snow, clouds and sea in Antarctica from Landsat 8 imagery: a new rock outcrop map and area estimation for the entire Antarctic continent Alex Burton-Johnson, Martin Black, Peter T. Fretwell, and Joseph Kaluza-Gilbert The Cryosphere, 10, 1665-1677, doi:10.5194/tc-10-1665-2016, 2016 We present a new rock outcrop map for the entire Antarctic continent, a principal base dataset for research and mapping in Antarctica with broad applications. To derive the map, a new methodology was developed and applied to allow automated identification of rock outcrops from Landsat 8 satellite images whilst excluding sunlit and shaded snow, clouds and liquid water – the first such automated methodology. The new dataset reveals that exposed rock forms only 0.18 % of the entire continent.

Description: Diagnosing the decline in climatic mass balance of glaciers in Svalbard over 1957–2014 Torbjørn Ims Østby, Thomas Vikhamar Schuler, Jon Ove Hagen, Regine Hock, Jack Kohler, and Carleen H. Reijmer The Cryosphere Discuss., doi:10.5194/tc-2016-172,2016 Manuscript under review for TC (discussion: open, 0 comments) We present modeled climatic mass balance for all glaciers in Svalbard for the period 1957–2014 at 1 km resolution using a coupled surface energy balance and snowpack model, thereby closing temporal and spatial gaps in direct and geodetic mass balance estimates. Supporting previous studies, our results indicate increased mass loss over the period. A detailed analysis of the involved energy fluxes reveals that increased mass loss is caused by atmospheric warming further amplified by feedbacks.

Description: Lightning risk assessment at a high spatial resolution using the resident sub-district scale: A case study in Beijing metropolitan areas Hai Bo Hu and Jing Xiao Li Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-231,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Lightning risk indexes identifying the potential number of dangerous lightning events (NDLEs) and ground sensitivity to lightning in resident sub-districts of Beijing metropolitan areas have been unprecedentedly estimated on a 5 m resolution grid. The gridded cloud to ground (CG) lightning stroke density was used in the NDLE calculation, on account of multiple contacts formed by CG lightning flash multiplicity. Meanwhile, in the NDLE estimates, the critical CG stroke gridded densities derived from the lightning location system (LLS) data were corrected for network detection efficiency (DE). This case study on resident sub-district indicates that the site-specific sensitivity to lightning, which is determined by the terrain factors related to lightning attachment, as well as lightning rod effects induced by nearby structures, differs greatly across types of underlying ground areas. The discrepancy of the NDLE which is the numerical product of sensitivity and CG stroke density, is predominated by the sensitivity on account of the relatively stationary CG stroke density in a resident sub-district scale. Conclusively, the visualization of lightning risk sensitivity and NDLE discrepancy in parts of a resident sub-district at high spatial resolution makes it convenient in risk reduction and risk control for lightning risk management.

Description: Simulating ice layer formation under the presence of preferential flow in layered snowpacks Nander Wever, Sebastian Würzer, Charles Fierz, and Michael Lehning The Cryosphere Discuss., doi:10.5194/tc-2016-185,2016 Manuscript under review for TC (discussion: open, 0 comments) The study presents a dual domain approach to simulate liquid water flow in snow using the 1-dimensional physics based snow cover model SNOWPACK. In this approach, the pore space is separated into a part for matrix flow and a part that represents preferential flow. Using this approach, water can percolate sub-freezing snow and form dense (ice) layers. A comparison with snow pits shows that some of the observed ice layers were reproduced by the model while others remain challenging to simulate.

Description: The unrest of the San Miguel volcano (El Salvador, Central America): installation of the monitoring network and observed volcano-tectonic ground deformation Alessandro Bonforte, Douglas Antonio Hernandez, Eduardo Gutiérrez, Louis Handal, Cecilia Polío, Salvatore Rapisarda, and Piergiorgio Scarlato Nat. Hazards Earth Syst. Sci., 16, 1755-1769, doi:10.5194/nhess-16-1755-2016, 2016 In this paper, we present the work done during an international cooperation between Italy and El Salvador, for implementing the multiparametric monitoring of the San Miguel volcano in El Salvador after its sudden unrest. In particular, the aim of this paper is to show and describe the installed geodetic network and to show, comment and interpret the very first detailed ground deformation data obtained on this volcano during an unrest period, useful for characterizing its unknown dynamics.

Description: Hydrodynamic modelling of coastal seas: the role of tidal dynamics in the Messina Strait, Western Mediterranean Sea Andrea Cucco, Giovanni Quattrocchi, Antonio Olita, Leopoldo Fazioli, Alberto Ribotti, Matteo Sinerchia, Costanza Tedesco, and Roberto Sorgente Nat. Hazards Earth Syst. Sci., 16, 1553-1569, doi:10.5194/nhess-16-1553-2016, 2016 This work explored the importance of considering the tidal dynamics when modelling the general circulation in the Messina Strait, a narrow passage connecting the Tyrrhenian and the Ionian Sea sub-basins in the Western Mediterranean Sea. The results highlight that tidal dynamics deeply impact the reproduction of the instantaneous and residual circulation pattern, waters thermohaline properties and transport dynamics both inside the Messina Strait and in the surrounding coastal and open waters.

Description: Heavy snow loads in Finnish forests respond regionally asymmetrically to projected climate change Ilari Lehtonen, Matti Kämäräinen, Hilppa Gregow, Ari Venäläinen, and Heli Peltola Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-184,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We studied the impact of projected climate change on the risk of snow-induced forest damage in Finland. Although winters are projected to become milder over the whole of Finland, our results suggest than in eastern and northern Finland the risk may increase while in southern and western parts of the country it is projected to decrease. This indicates that there is increasing need to consider the potential of snow damage in forest management in eastern and northern Finland.

Description: Review article: Potential application of surface methods for the monitoring of organic matter dynamics in marine systems Galja Pletikapić and Nadica Ivošević DeNardis Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-178,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We present the potential of non-invasive surface methods, the electrochemical method applied with atomic force microscopy imaging (AFM), and its application for monitoring needs undertaken in the Adriatic sea. Electrochemical approach enables simple and fast analysis of a large number of raw seawater samples due to the simultaneous differentiation of organic constituents in seawater. AFM allows direct visualization and structural organization of marine organic matter at nanometer scales.

Description: Marine ice sheet model performance depends on basal sliding physics and sub-shelf melting Rupert Michael Gladstone, Roland Charles Warner, Benjamin Keith Galton-Fenzi, Olivier Gagliardini, Thomas Zwinger, and Ralf Greve The Cryosphere Discuss., doi:10.5194/tc-2016-149,2016 Manuscript under review for TC (discussion: open, 0 comments) Computer models are used to simulate the behaviour of glaciers and ice sheets. It has been found that such models are required to be run at very high resolution (which means high computational expense) in order to accurately represent the evolution of marine ice sheets (ice sheets resting on bedrock below sea level), in certain situations.

Description: Effects of Seasonal Snow Cover on Hydrothermal Conditions of the Active Layer in the Northeastern Qinghai-Tibet Plateau Ji Chen, Yu Sheng, Qingbai Wu, Lin Zhao, Jing Li, and Jingyi Zhao The Cryosphere Discuss., doi:10.5194/tc-2016-134,2016 Manuscript under review for TC (discussion: open, 0 comments) The extreme thin and short-time snow cover in the northeastern Qinghai-Tibet plateau is predominantly during spring and autumn. Removal of seasonal snow cover is beneficial for cooling the active layer in the first few years. Seasonal snow cover maintains the high water content of the active layer because of the inhibitory action of snow cover on the evaporation capacity in the natural site during the daytime and in summer. Snow removal can therefore lead to a rapid decrease of soil moisture.

Description: Surface mass balance and water stable isotopes derived from firn cores on three ice rises, Fimbul Ice Shelf, Antarctica Carmen P. Vega, Elisabeth Schlosser, Dmitry V. Divine, Jack Kohler, Tõnu Martma, Anja Eichler, Margit Schwikowski, and Elisabeth Isaksson The Cryosphere Discuss., doi:10.5194/tc-2016-164,2016 Manuscript under review for TC (discussion: open, 0 comments) Surface mass balance and water stable isotopes from firn cores on three ice rises at Fimbul Ice Shelf, are reported. The results suggest that the ice rises are suitable sites for the retrieval of longer firn and ice cores. The first deuterium excess data for the area suggests a possible role of seasonal moisture transport changes on the annual isotopic signal. Large-scale atmospheric circulation patterns most likely provide the dominant influence on water stable isotope ratios at the sites.

Description: GPS-derived ground deformation (2005–2014) within the Gulf of Mexico region referred to a stable Gulf of Mexico reference frame Jiangbo Yu and Guoquan Wang Nat. Hazards Earth Syst. Sci., 16, 1583-1602, doi:10.5194/nhess-16-1583-2016, 2016 The study establishes the first local reference frame for the Gulf of Mexico region using the observations from 13 GNSS sites. The root mean square (RMS) of the velocities of the 13 reference stations achieves 0.2 mm yr −1 in the horizontal and 0.3 mm yr −1 in the vertical directions. Land subsidence, faulting, and salt dome activities in the Houston region, Mexico City, and the southeastern Louisiana region are discussed and compared.

Description: GIS analysis of effects of future Baltic sea level rise on the island of Gotland, Sweden Karin Ebert, Karin Ekstedt, and Jerker Jarsjö Nat. Hazards Earth Syst. Sci., 16, 1571-1582, doi:10.5194/nhess-16-1571-2016, 2016 Future sea level rise is inevitable. We investigate the effects of 2 m sea level rise on the island of Gotland, Sweden. In a multi-criteria analysis we analyze the quantity of infrastructure that will be inundated, and the effect of saltwater intrusion in wells. Almost 100 km 2 (3 %) of Gotland's land area will be inundated. Important touristic and nature values will be strongest affected. Well salinization will greatly increase. Administrative planning is needed to prepare for changes.

Description: Reflective properties of white and snow-covered sea ice Aleksey Malinka, Eleonora Zege, Georg Heygster, and Larysa Istomina The Cryosphere Discuss., doi:10.5194/tc-2016-153,2016 Manuscript under review for TC (discussion: open, 0 comments) The amount of melt ponds on Arctic summer sea ice and its reflectance are required for better climate modelling and weather prediction. In order to derive these quantities from optical satellite observations, simple analytical formulas for the bidirectional reflectance factor and albedo at direct and diffuse incidence are derived from basic assumptions and verified with in situ measurements made during the expedition ARK-XXVII/3 of research vessel Polarstern in 2012.

Description: TESSA: design and implementation of a platform for Situational Sea Awareness M. Scalas, P. Marra, L. Tedesco, R. Quarta, E. Cantoro, A. Tumolo, D. Rollo, and M. Spagnulo Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-166,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This article describes the architecture of Sea Situational Awareness (SSA) platform, a major asset within "TESSA", an industrial research project funded by the Italian Ministry of Education and Research. The main aim of the platform is to collect, transform and provide forecast and observational data as information suitable for delivery across a variety of channels, like web and mobile; specifically, the ability to produce and provide forecast information suitable for creating SSA-enabled applications has been a critical driving factor when designing and evolving the whole architecture. Thus, starting from functional and performance requirements, the platform architecture is described in terms of its main building blocks and flows among them: front-end components that support end-user applications and map and data analysis components that allow for serving maps and querying data. Focus is directed to key aspects and decisions about the main issues faced, like interoperability, scalability, efficiency and adaptability, but it also considers insights about future works in this and similarly related subjects. Some analysis results are also provided in order to better characterize critical issues and related solutions.

Description: Hydrodynamic characterization of past flash-flood events and their associated hazards from dendrogeomorphological evidence in Caldera de Taburiente National Park (Canary Islands, Spain) Julio Garrote, Andrés Diez-Herrero, José M. Bodoque, María A. Perucha, Pablo Mayer, and Mar Genova Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-206,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The paper shows a study assessing different flooding scenarios based on the height of scars in trees as indicators for peak discharge estimation in an ungauged fluvial basin with sand and gravel riverbed. The use of scars on trees together with the combined use of 2D hydraulic model and LIDAR topographic data, has allowed a better peak discharge estimation of January, 11–13, 1997 flash flood and its related hazards, than estimation from rainfall data. This could improve flooding risk mapping.

Description: Brief communication "Loss and Damage from a catastrophic landslide in Nepal" Kees van der Geest and Markus Schindler Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-210,2016 Manuscript under review for NHESS (discussion: open, 0 comments) In August 2014, a major landslide struck in a densely populated district 80 km northeast of Nepal's capital Kathmandu, in Sindhupalchok District. This study combines evidence from surveyes and intereviews to assess impacts, and preventive and coping measures taken. The impacts relative to annual income show that the poor lost up to 14 times their annual income, as opposed to 3 times for the non-poor. The implications of these findings for discussions surrounding loss and damage are discussed.

Description: The catastrophic landfill flowslide at Hongao dumpsite on December 20, 2015 in Shenzhen, China Qiang Xu, Dalei Peng, Weile Li, Xiujun Dong, Wei Hu, Minggao Tang, and Fangzhou Liu Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-196,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The article aims at presenting the first-hand dataset and results from the field investigation, laboratory test, and numerical analysis for the flowslide occurred on December 20, 2015, in Shenzhen, China; A devastating event resulted in significant human and property losses. The article concluded that the landfill stagnated groundwater flow and resulted in high water pressure due to the absence of drainage system with both disposal rate and amount exceeding the maximum design capacity.

Description: Application and validation of long-range terrestrial laser scanning to monitor the mass balance of very small glaciers in the Swiss Alps Mauro Fischer, Matthias Huss, Mario Kummert, and Martin Hoelzle The Cryosphere, 10, 1279-1295, doi:10.5194/tc-10-1279-2016, 2016 This study provides the first thorough validation of geodetic glacier mass changes derived from close-range high-resolution remote sensing techniques, and highlights the potential of terrestrial laser scanning for repeated mass balance monitoring of very small alpine glaciers. The presented methodology is promising, as laborious and potentially dangerous in situ measurements as well as the spatial inter- and extrapolation of point measurements over the entire glacier can be circumvented.

Description: Global distribution of winter lightning: a threat to wind turbines and aircraft Joan Montanyà, Ferran Fabró, Oscar van der Velde, Víctor March, Earle Rolfe Williams, Nicolau Pineda, David Romero, Glòria Solà, and Modesto Freijo Nat. Hazards Earth Syst. Sci., 16, 1465-1472, doi:10.5194/nhess-16-1465-2016, 2016 Lightning is one of the major threats to modern multi-megawatt wind turbines and a concern for new generation of aircraft. Both wind turbines and aircraft can initiate lightning and very favourable conditions for lightning initiation occur in winter thunderstorms. Moreover, winter thunderstorms are characterized for producing very energetic lightning. In this paper we present the global winter lightning activity. Japan, US, Mediterranean, Argentina and New Zealand are the most active areas.

Description: SeaConditions: a web and mobile service for safer professional and recreational activities in the Mediterranean Sea G. Coppini, P. Marra, R. Lecci, N. Pinardi, S. Cretì, M. Scalas, L. Tedesco, A. D'Anca, L. Fazioli, A. Olita, G. Turrisi, C. Palazzo, G. Aloisio, S. Fiore, A. Bonaduce, Y. Kumar, S. A. Ciliberti, I. Federico, G. Mannarini, P. Agostini, R. Bonarelli, S. Martinelli, G. Verri, L. Lusito, D. Rollo, A. Cavallo, A. Tumolo, T. Monacizzo, M. Spagnulo, R. Sorgente, A. Cucco, G. Quattrocchi, M. Tonani, M. Drudi, L. Panzera, A. Navarra, and G. Negro Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-176,2016 Manuscript under review for NHESS (discussion: open, 0 comments) SeaCondition aims to support the users providing the environmental information in due time and with the adequate accuracy in the marine and coastal environment enforcing users' Sea Situational Awareness. SeaConditions consists of a web and mobile application for the provision of meteorological and oceanographic observation and forecasting products. The iOS/Android apps were downloaded by more than 105 000 users and more than 100 000 users have visited the web version ( http://www.sea-conditions.com ).

Description: Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series Ghislain Picard, Quentin Libois, Laurent Arnaud, Gauthier Verin, and Marie Dumont The Cryosphere, 10, 1297-1316, doi:10.5194/tc-10-1297-2016, 2016 Albedo of snow surfaces depends on snow grain size. By measuring albedo during 3 years at Dome C in Antarctica with an automatic spectroradiometer, we were able to monitor the snow specific surface area and show an overall growth of the grains in spring and summer followed by an accumulation of small-grained snow from mid-summer. This study focuses on the uncertainties due to the spectroradiometer and concludes that the observed variations are significant with respect to the precision.

Description: Operational algorithm for ice/water classification on dual-polarized RADARSAT-2 images Natalia Zakhvatkina, Anton Korosov, Stefan Muckenhuber, Stein Sandven, and Mohamed Babiker The Cryosphere Discuss., doi:10.5194/tc-2016-131,2016 Manuscript under review for TC (discussion: open, 0 comments) The presented fully automated algorithm distinguishes open water (rough/calm) and sea ice based on dual-polarized RS2 SAR images. Texture features are used for Support Vector Machines supervised image classification. The algorithm includes pre-processing and validation procedures. More than 2700 scenes were processed and the results show the good discrimination between open water and sea ice areas with accuracy 91 % compared with ice charts produced by MET Norway service.

Description: Three-year monitoring of stable isotopes of precipitation at Concordia Station, East Antarctica Barbara Stenni, Claudio Scarchilli, Valerie Masson-Delmotte, Elisabeth Schlosser, Virginia Ciardini, Giuliano Dreossi, Paolo Grigioni, Mattia Bonazza, Anselmo Cagnati, Daniele Karlicek, Camille Risi, Roberto Udisti, and Mauro Valt The Cryosphere Discuss., doi:10.5194/tc-2016-142,2016 Manuscript under review for TC (discussion: open, 0 comments) Here, we focus on the Concordia Station, central East Antarctic plateau, providing a multi-year record (2008–2010) of daily precipitation types identified from crystal morphologies, precipitation amounts, and isotopic composition. Relationships between local meteorological data and precipitation oxygen isotope composition are investigated. Our dataset is available for in depth model evaluation at the synoptic scale.

Description: Greenland Ice Sheet seasonal and spatial mass variability from model simulations and GRACE (2003–2012) Patrick M. Alexander, Marco Tedesco, Nicole-Jeanne Schlegel, Scott B. Luthcke, Xavier Fettweis, and Eric Larour The Cryosphere, 10, 1259-1277, doi:10.5194/tc-10-1259-2016, 2016 We compared satellite-derived estimates of spatial and seasonal variations in Greenland Ice Sheet mass with a set of model simulations, revealing an agreement between models and satellite estimates for the ice-sheet-wide seasonal fluctuations in mass, but disagreement at finer spatial scales. The model simulations underestimate low-elevation mass loss. Improving the ability of models to capture variations and trends in Greenland Ice Sheet mass is important for estimating future sea level rise.

Description: Stand-Alone Tsunami Alarm Equipment Akio Katsumata, Yutaka Hayashi, Kazuki Miyaoka, Hiroaki Tsushima, Toshitaka Baba, Patricio A. Catalán, Cecilia Zelaya, Felipe Riquelme Vasquez, Rodrigo Sanchez-Olavarria, and Sergio Barrientos Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-164,2016 Manuscript under review for NHESS (discussion: open, 0 comments) One of the quickest means of tsunami evacuation is transfer to higher ground soon after strong and long ground-shaking. Strong ground motion means that the hypocenter of the event is close to the current location, and long ground-shaking means that the size of the earthquake is large. We investigated the possibility to apply this to tsunami hazard alarm using single-site observation of ground shaking.

Description: Development and analysis of a continuous record of global near-surface soil freeze/thaw patterns from AMSR-E and AMSR2 data Tongxi Hu, Tianjie Zhao, Jiancheng Shi, Tianxing Wang, Dabin Ji, Ahmad Al Bitar, Bin Peng, and Yurong Cui The Cryosphere Discuss., doi:10.5194/tc-2016-115,2016 Manuscript under review for TC (discussion: open, 0 comments) We present an approach of satellite remote sensing to derive a continuous long term and stable data record of the near-surface freeze/thaw cycle over the permafrost and seasonally frozen ground. We find that the distribution of the frost days and its trend variations are consistent with the minimum temperature anomalies. Analysis over the Qinghai-Tibetan Plateau demonstrates that the frost period is shortening slightly over the past decade, and the last frost date is advanced in most regions.

Description: Which are the highest peaks in the US Arctic? Fodar settles the debate Matt Nolan and Kit DesLauriers The Cryosphere, 10, 1245-1257, doi:10.5194/tc-10-1245-2016, 2016 We measured the heights of the five tallest peaks in the US Arctic using fodar, a new airborne photogrammetric technique using structure-from-motion software. The highest peaks are Mt Isto (2735.6 m), Mt. Hubley (2717.6 m), Mt. Chamberlin (2712.3 m), Mt. Michelson (2698.1 m), and an unnamed peak (2694.9 m). We found fodar suitable for topographic change detection on the centimeter scale in steep mountain terrain, such as for measuring snow depths.

Description: Atmospheric and ionospheric coupling phenomena related to large earthquakes M. Parrot, V. Tramutoli, Tiger J. Y. Liu, S. Pulinets, D. Ouzounov, N. Genzano, M. Lisi, K. Hattori, and A. Namgaladze Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-172,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Since tens of years perturbations have been observed in the ionosphere prior to earthquakes (between a few hours and a few days before). But the mechanism to understand how the earthquake preparation in a seismic area can induce a change in the ionosphere is the subject of intense debate. In this paper we present various atmospheric and ionospheric perturbations observed prior to large earthquakes in order to support a model of coupling between the lithosphere, the atmosphere, and the ionosphere.

Description: Regional impacts of global change: seasonal trends in extreme rainfall, run-off and temperature in two contrasting regions of Morocco Kenza Khomsi, Gil Mahe, Yves Tramblay, Mohamed Sinan, and Maria Snoussi Nat. Hazards Earth Syst. Sci., 16, 1079-1090, doi:10.5194/nhess-16-1079-2016, 2016 The study investigates trends in mean and extreme rainfall, run-off, temperature and their relationship with large-scale atmospheric circulation. It focuses on two Moroccan watersheds; Bouregreg and Tensift, using data from 1977 to 2003. Results do not show a homogeneous behaviour in the catchments; the influence of the large-scale atmospheric circulation is different and a clear spatial dependence of the trend analysis is linked to the distance from the coast and the mountains.

Description: Assessment of Arctic and Antarctic Sea Ice Predictability in CMIP5 Decadal Hindcasts Chao-Yuan Yang, Jiping Liu, Yongyun Hu, Radley M. Horton, Liqi Chen, and Xiao Cheng The Cryosphere Discuss., doi:10.5194/tc-2016-97,2016 Manuscript under review for TC (discussion: open, 0 comments) This paper examines the ability of coupled global climate models to predict decadal variability of Arctic and Antarctic sea ice. We analyze decadal hindcasts/predictions of 11 CMIP5 models. Decadal hindcasts exhibit a large multi-model spread in the simulated sea ice extent, with some models deviating significantly from the observations. For the models having large biases and using full-field initialization, the predicted sea ice extent quickly drifts away from the initial constraint, deteriorating the decadal predictive skill. The anomaly correlation analysis between the decadal hindcast and observed sea ice suggests that in the Arctic, for most models, the areas showing significant predictive skill become broader associated with increasing lead times. This area expansion is largely because nearly all the models are capable of predicting the observed decreasing Arctic sea ice cover. Sea ice extent in the north Pacific has better predictive skill than that in the north Atlantic (particularly at a lead-time of 3–7 years), but there is a re-emerging predictive skill in the north Atlantic at a lead-time of 6–8 years. In contrast to the Arctic, Antarctic sea ice decadal hindcasts do not show broad predictive skill at any time scales, and there is no obvious improvement linking the areal extent of significant predictive skill to lead-time increase. This might be because nearly all the models predict a retreating Antarctic sea ice cover, opposite to the observations. For the Arctic, the predictive skill of the MMEE outperforms most models and the persistence prediction at longer time scales, which is not the case for the Antarctic.

Description: FLOPROS: an evolving global database of flood protection standards Paolo Scussolini, Jeroen C. J. H. Aerts, Brenden Jongman, Laurens M. Bouwer, Hessel C. Winsemius, Hans de Moel, and Philip J. Ward Nat. Hazards Earth Syst. Sci., 16, 1049-1061, doi:10.5194/nhess-16-1049-2016, 2016 Assessments of flood risk, on global to local scales, are becoming more urgent with ongoing climate change and with rapid socioeconomic developments. Such assessments need information about existing flood protection, still largely unavailable. Here we present the first open-source database of FLood PROtection Standards, FLOPROS, which enables more accurate modelling of flood risk. We also invite specialists to contribute new information to this evolving database.

Description: Surface movement above an underground coal longwall mine after closure André Vervoort Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-134,2016 Manuscript under review for NHESS (discussion: open, 0 comments) Underground coal mining induces surface movement with damage to infrastructure. The best known phenomenon is the downward movement or subsidence during the life of the mine. However, it has been observed that after the closure of the mine there is first a period of still residual subsidence, followed by an upwards movement or uplift. This uplift is the direct result of the flooding of the underground workings. By conducting this research the long term impact of mining is better quantified.

Description: The street, an area exposed to earthquakes (the Lorca case, Spain 2011) M. B. Rojo, E. Beck, and C. Lutoff Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-115,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The Lorca earthquake (Spain, 11-05-2011) caused considerable damages, including a building collapse. This earthquake killed 9 persons affected outside the buildings, on the street, and more than 300 people injured. Studying this specific human exposure requires an adapted methodolgy. This article proposes a dynamic and spatio-temporal approach of individual mobility during the seismic crisis. Its application on Lorca case shows spatial and temporal variability of individual exposure level in the street during the hours following the shake. Not really studied until now, this specific human exposure deserves more attention particularly in zones of moderate seismicity, like Euromediterranean area.

Description: Relationships between Snowfall Densities and the Main Types of Solid Hydrometeors Deduced from Measured Size and Fall Speed, for snowpack modeling applications Masaaki Ishizaka, Hiroki Motoyoshi, Satoru Yamaguchi, Sento Nakai, Toru Shina, and Ken-ichiro Muramoto The Cryosphere Discuss., doi:10.5194/tc-2016-68,2016 Manuscript under review for TC (discussion: open, 0 comments) We measured the snowfall densities, simultaneously observing the predominant snowfall types determined by the measured size and the fall speed with CCD camera. We obtain the quantitative relationships between snowfall densities and presumed density derived from the size and mass components with CCD camera. This suggests the possibility of estimating snowfall densities from the measured size and the fall speed data, and using them as the initial densities for a snow pack in a numerical model.

Description: Empirical Study on Drought Adaptation of Regional Rainfed Agriculture in China Zhiqiang Wang, Qing Ma, Siyu Chen, Lan Deng, and Jingyi Jiang Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-94,2016 Manuscript under review for NHESS (discussion: open, 0 comments) With global warming, the risk of agricultural drought is increasing. Through the empirical analysis of this paper, it found that farmers and the government always spontaneously adjust their development demands and take measures to adapt to environmental change, thus a dynamic agricultural drought adaptation model with the regional characteristics was formed in the area. Agricultural drought risk (R) is the function of environment (E), demand (D) and adaptation (A), or R = f (E, D, A).

Description: On the recent contribution of the Greenland ice sheet to sea level change Michiel van den Broeke, Ellyn Enderlin, Ian Howat, Peter Kuipers Munneke, Brice Noël, Willem Jan van de Berg, Erik van Meijgaard, and Bert Wouters The Cryosphere Discuss., doi:10.5194/tc-2016-123,2016 Manuscript under review for TC (discussion: open, 0 comments) We present recent (1958–2015) mass balance time series for the Greenland ice sheet. We show that recent mass loss is caused by a combination of increased surface meltwater runoff and solid ice discharge. Most meltwater above 2000 m a.s.l. refreezes in the cold firn and does not leave the ice sheet, but this goes at the expense of firn heating and densifying. In spite of a temporary rebound in 2013, it appears that the ice sheet remains in a state of persistent mass loss

Description: Improving satellite-retrieved surface radiative fluxes in polar regions using a smart sampling approach Kristof Van Tricht, Stef Lhermitte, Irina V. Gorodetskaya, and Nicole P. M. van Lipzig The Cryosphere Discuss., doi:10.5194/tc-2016-103,2016 Manuscript under review for TC (discussion: open, 0 comments) Despite the crucial role of polar regions in the global climate system, the limited availability of observations on the ground hampers a detailed understanding of their energy budget. Here we develop a method to use satellites to fill these observational gaps. We show that by sampling satellite observations in a smart way, coverage is greatly enhanced. We conclude that this method might help improving our understanding of the polar energy budget, and ultimately its effects in the global climate.

Description: Reconstructing the mass balance of Brewster Glacier, New Zealand, using MODIS-derived glacier-wide albedo Pascal Sirguey, Holly Still, Nicolas J. Cullen, Marie Dumont, Yves Arnaud, and Jonathan P. Conway The Cryosphere Discuss., doi:10.5194/tc-2016-98,2016 Manuscript under review for TC (discussion: open, 0 comments) 14 years of satellite observations are used to monitor the albedo of Brewster Glacier, New Zealand and estimate annual and seasonal balances. This confirms the governing role of the summer balance in the annual balance and allows the reconstruction of the annual balance back to 1977 using a photographic record of the snowline. The longest mass balance record for a New Zealand glacier shows that negative balances after 2008 yielded a loss of 35 % of the gain accumulated over the previous 30 years.

Description: Impacts of marine instability across the East Antarctic Ice Sheet on Southern Ocean dynamics Steven J. Phipps, Christopher J. Fogwill, and Christian S. M. Turney The Cryosphere Discuss., doi:10.5194/tc-2016-111,2016 Manuscript under review for TC (discussion: open, 0 comments) We explore the effects of melting of the East Antarctic Ice Sheet on the Southern Ocean. Using a climate model, we find that melting changes the ocean circulation and causes warming of more than 1 ºC at depth. We also discover the potential existence of a "domino effect", whereby the initial warming spreads westwards around the Antarctic continent. Melting of just one sector could therefore destabilise the wider Antarctic Ice Sheet, leading to substantial increases in global sea level.

Description: Modeling debris-covered glaciers: response to steady debris deposition Leif S. Anderson and Robert S. Anderson The Cryosphere, 10, 1105-1124, doi:10.5194/tc-10-1105-2016, 2016 Mountains erode and shed rocks down slope. When these rocks (debris) fall on glacier ice they can suppress ice melt. By protecting glaciers from melt, debris can make glaciers extend to lower elevations. Using mathematical models of glaciers and debris deposition, we find that debris can more than double the length of glaciers. The amount of debris deposited on the glacier, which scales with mountain height and steepness, is the most important control on debris-covered glacier length and volume.

Description: Estimating the extent of Antarctic summer sea ice during the Heroic Age of Exploration Tom Edinburgh and Jonathan J. Day The Cryosphere Discuss., doi:10.5194/tc-2016-90,2016 Manuscript under review for TC (discussion: open, 0 comments) A lack of sea ice data in the pre-satellite period limits our ability to quantify the sensitivity of sea ice to climate change and validate climate models. This paper analyses direct observations of the nature of sea ice as recorded in ship logbooks during the Heroic Age of Antarctic exploration for the first time and shows that the summer ice edge was up to 1.7° further north in the Weddell Sea during this period but that ice conditions were comparable to the present day in other sectors.

Description: Glacier melting and precipitation trends detected by surface area changes in Himalayan ponds Franco Salerno, Sudeep Thakuri, Nicolas Guyennon, Gaetano Viviano, and Gianni Tartari The Cryosphere Discuss., doi:10.5194/tc-2016-39,2016 Manuscript under review for TC (discussion: open, 0 comments) This contribution shows that the surface area variations of unconnected glacial ponds, i.e., ponds not directly connected to glaciers, can be considered suitable proxies for detecting changes in the main hydrological components of the water balance on the south side of Mt. Everest.

Description: Research trends on hazards, disasters, risk reduction and climate change in Indonesia: a systematic literature review Riyanti Djalante Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-112,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The paper examines progress in research related hazards, risks, disasters, disaster risk reduction and management in Indonesia. It also reviews the roles of Indonesian authors in those publications. The study finds that majority of research focusses on hazards while only recently they focusses on risk reduction and management. This study recommends future research needs and capacity building in writing and collaboration between Indonesia and international researchers.

Description: From event analysis to global lessons: disaster forensics for building resilience Adriana Keating, Kanmani Venkateswaran, Michael Szoenyi, Karen MacClune, and Reinhard Mechler Nat. Hazards Earth Syst. Sci., 16, 1603-1616, doi:10.5194/nhess-16-1603-2016, 2016 We present a disaster forensics methodology: the post-event review capability (PERC), which responds to a need for learning about the successes and failures in disaster risk management (DRM) and resilience, uncovers the underlying drivers of increasing risk and makes actionable recommendations. We analyse seven PERC reports and find that across the globe policy makers and practitioners in DRM face strikingly similar challenges. These lessons highlight the importance of integrated risk reduction.

Description: Brief Communication: Twelve-year cyclic surging episodes at Donjek Glacier in Yukon, Canada Takahiro Abe, Masato Furuya, and Daiki Sakakibara The Cryosphere, 10, 1427-1432, doi:10.5194/tc-10-1427-2016, 2016 We identified 12-year cyclic surging episodes at Donjek Glacier in Yukon, Canada. The surging area is limited within the ~20km section from the terminus, originating in an area where the flow width significantly narrows downstream. Our results suggest strong control of the valley constriction on the surge dynamics.

Description: Strain localisation and dynamic recrystallisation in the ice-air aggregate: A numerical study Florian Steinbach, Paul D. Bons, Albert Griera, Daniela Jansen, Maria-Gema Llorens, Jens Roessiger, and Ilka Weikusat The Cryosphere Discuss., doi:10.5194/tc-2016-167,2016 Manuscript under review for TC (discussion: open, 0 comments) How glaciers or ice sheets flow is a result of microscopic processes controlled by the properties of individual ice crystals. We performed computer simulations on these processes and the effect of air bubbles between crystals. The simulations show that small scale ice deformation is locally stronger than in other regions, which is enhanced by bubbles. This causes the ice crystals to recrystallise and change their properties in a way that potentially also affects the large scale flow properties.

Description: Glacier melting and precipitation trends detected by surface area changes in Himalayan ponds Franco Salerno, Sudeep Thakuri, Nicolas Guyennon, Gaetano Viviano, and Gianni Tartari The Cryosphere, 10, 1433-1448, doi:10.5194/tc-10-1433-2016, 2016 This contribution shows that the surface area variations of unconnected glacial ponds, i.e. ponds not directly connected to glacier ice, can be considered as suitable proxies for detecting past changes in the main hydrological components of the water balance (glacier melt, precipitation, evaporation) on the south side of Mt Everest.

Description: Landfast ice thickness in the Canadian Arctic Archipelago from observations and models Stephen E. L. Howell, Frédéric Laliberté, Ron Kwok, Chris Derksen, and Joshua King The Cryosphere, 10, 1463-1475, doi:10.5194/tc-10-1463-2016, 2016 The Canadian Ice Service record of observed landfast ice and snow thickness represents one of the longest in the Arctic that spans over 5 decades. We analyze this record to report on long-term trends and variability of ice and snow thickness within the Canadian Arctic Archipelago (CAA). Results indicate a thinning of ice at several sites in the CAA. State-of-the-art climate models still have difficultly capturing observed ice thickness values in the CAA and should be used with caution.

Description: An examination of land use impacts of sea level rise induced flooding Jie Song, Xinyu Fu, Yue Gu, Yujun Deng, and Zhong-Ren Peng Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-157,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We present a joint model which couples urban growth dynamics with coastal hazards. We use the SLEUTH platform to investigate three urban growth scenarios under different land use policies. We found that compact development may contribute to the region's vulnerability to sea level rise induced flooding, and that strict land development regulations may greatly mitigate such vulnerability. The findings highlight the importance of land use simulations in formulating coastal management plans.

Description: Natural hazard fatalities in Switzerland from 1946 to 2015 Alexandre Badoux, Norina Andres, Frank Techel, and Christoph Hegg Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-232,2016 Manuscript under review for NHESS (discussion: open, 0 comments) A database of fatalities caused by natural hazards in Switzerland was compiled for the period from 1946 to 2015: In 70 years, 635 events occurred causing 1023 fatalities. The most common causes of death were snow avalanches (37 %), followed by lightning (16 %), floods (12 %), windstorms (10 %), rockfalls (8 %) and landslides (7 %). The annual number of victims showed a distinct decrease over time. In comparison to other countries worldwide, the natural hazard fatality rate in Switzerland is quite low.

Description: Coastal flooding: impact of waves on storm surge during extremes. A case study for the German Bight Joanna Staneva, Kathrin Wahle, Wolfgang Koch, Arno Behrens, Luciana Fenoglio-Marc, and Emil V. Stanev Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-227,2016 Manuscript under review for NHESS (discussion: open, 0 comments) This study addresses impact of wind, waves, tidal forcing and baroclinicity on the sea level. Their role is quantified and the results are compared with observations. The analyses of the coupled model results reveal a closer match with observations than for the stand-alone circulation model, especially during the extremes. The improved performance resulting from the new developments justifies further use of coupled models for improvement of coastal flooding predictions.

Description: Influence of expertise on rockfall hazard assessment using empirical methods Adeline Delonca, Thierry Verdel, and Yann Gunzburger Nat. Hazards Earth Syst. Sci., 16, 1657-1672, doi:10.5194/nhess-16-1657-2016, 2016 Rockfall hazard zoning analyses can be based on qualitative observations. For this reason, expertise is of great importance in determining the hazard. To test this hypothesis, an experiment is proposed to evaluate the importance of subjective assessment: three populations with different level of expertise assessed the level of rockfall hazard on three sites using a qualitative and a quantitative method. A statistical analysis shows that there is a non-significant influence of the level of expertise.

Description: The role of EMODnet Chemistry in the European challenge for Good Environmental Status Matteo Vinci, Alessandra Giorgetti, and Marina Lipizer Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-226,2016 Manuscript under review for NHESS (discussion: open, 0 comments) EMODnet initiative aims to provide access to European marine data in an interoperable and free of restrictions way. The Chemistry lot focus on the fulfillment of EU MSFD and INSPIRE directives requirements to assess eutrophication and contaminants. It could play two main roles: provide standardized and quality checked buffers of data for specific Regions and act as an umbrella for standards, best practices and infrastructure to aggregate at Regional level the single member states.

Description: Microstructure representation of snow in coupled snowpack and microwave emission models Melody Sandells, Richard Essery, Nick Rutter, Leanne Wake, Leena Leppänen, and Juha Lemmetyinen The Cryosphere Discuss., doi:10.5194/tc-2016-181,2016 Manuscript under review for TC (discussion: open, 0 comments) This study looks at a wide range of options for simulating sensor signals for satellite monitoring of water stored as snow, though an ensemble of 1323 coupled snow evolution and microwave scattering models. The greatest improvements will be made with better computer simulations of how the snow microstructure changes, followed by how the microstructure scatters radiation at microwave frequencies. Snow compaction should also be considered in systems to monitor snow mass from space.

Description: Wave climate in the Arctic 1992–2014: seasonality and trends Justin E. Stopa, Fabrice Ardhuin, and Fanny Girard-Ardhuin The Cryosphere, 10, 1605-1629, doi:10.5194/tc-10-1605-2016, 2016 Satellite observations show the Arctic sea ice has decreased the last 30 years. From our wave model hindcast and satellite altimeter datasets we observe profound increasing wave heights, which are caused by the loss of sea ice and not the driving winds. If ice-free conditions persist later into fall, then regions like the Beaufort–Chukchi Sea will be prone to developing larger waves since the driving winds are strong this time of year.

Description: Drift simulation of MH370 debris using superensemble techniques Eric Jansen, Giovanni Coppini, and Nadia Pinardi Nat. Hazards Earth Syst. Sci., 16, 1623-1628, doi:10.5194/nhess-16-1623-2016, 2016 In March 2014, a commercial airliner vanished without a trace. The main wreckage of the plane was never recovered, except for some small parts that washed up more than 17 months after the disappearance. In this paper we show a method to model the most likely trajectories of floating debris from the aircraft. The results show that the assumed area of the crash site is compatible with the recovered debris and predict that further debris may be found along the African east coast.

Description: Spatial-Temporal Clustering of Tornadoes Bruce D. Malamud and Donald L. Turcotte Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-71,2016 Manuscript under review for NHESS (discussion: open, 0 comments) We introduce a novel method for the spatio-temporal cluster analysis of severe tornado touchdowns that are part of tornado outbreaks. Tornado outbreaks, groups of tornadoes that occur close to each other temporally and spatially, constitute a severe hazard that have few quantitative measures. Our new approach, which we illustrate using two severe tornado outbreaks from 2011, differentiates between types of tornado outbreaks, and within outbreaks, identification of clusters in both time & space.

Description: A coupled wave-3D hydrodynamics model of the Taranto Sea (Italy): a multiple-nesting approach Maria Gabriella Gaeta, Achilleas G. Samaras, Ivan Federico, and Renata Archetti Nat. Hazards Earth Syst. Sci. Discuss., doi:10.5194/nhess-2016-95,2016 Manuscript under review for NHESS (discussion: open, 0 comments) The present work describes an operational strategy for the development of a multiscale modelling system, based on a multiple–nesting approach and open–source numerical models. The strategy was applied and validated for the Gulf of Taranto in South Italy, scaling large–scale oceanographic model results to high–resolution coupled wave–3D hydrodynamics simulations for the area of Mar Grande in Taranto Sea. The spatial and temporal high – resolution simulations were performed using the open–source.