Articles | Volume 21, issue 9
26 Sep 2017
Research article | 26 Sep 2017
Use of reflected GNSS SNR data to retrieve either soil moisture or vegetation height from a wheat crop
Sibo Zhang et al.
No articles found.
Arsène Druel, Simon Munier, Anthony Mucia, Clément Albergel, and Jean-Christophe Calvet
Geosci. Model Dev., 15, 8453–8471,Short summary
Crop phenology and irrigation is implemented into a land surface model able to work at a global scale. A case study is presented over Nebraska (USA). Simulations with and without the new scheme are compared to different satellite-based observations. The model is able to produce a realistic yearly irrigation water amount. The irrigation scheme improves the simulated leaf area index, gross primary productivity, evapotransipiration, and land surface temperature.
Anthony Mucia, Bertrand Bonan, Clément Albergel, Yongjun Zheng, and Jean-Christophe Calvet
Biogeosciences, 19, 2557–2581,Short summary
For the first time, microwave vegetation optical depth data are assimilated in a land surface model in order to analyze leaf area index and root zone soil moisture. The advantage of microwave products is the higher observation frequency. A large variety of independent datasets are used to verify the added value of the assimilation. It is shown that the assimilation is able to improve the representation of soil moisture, vegetation conditions, and terrestrial water and carbon fluxes.
Wouter Dorigo, Irene Himmelbauer, Daniel Aberer, Lukas Schremmer, Ivana Petrakovic, Luca Zappa, Wolfgang Preimesberger, Angelika Xaver, Frank Annor, Jonas Ardö, Dennis Baldocchi, Marco Bitelli, Günter Blöschl, Heye Bogena, Luca Brocca, Jean-Christophe Calvet, J. Julio Camarero, Giorgio Capello, Minha Choi, Michael C. Cosh, Nick van de Giesen, Istvan Hajdu, Jaakko Ikonen, Karsten H. Jensen, Kasturi Devi Kanniah, Ileen de Kat, Gottfried Kirchengast, Pankaj Kumar Rai, Jenni Kyrouac, Kristine Larson, Suxia Liu, Alexander Loew, Mahta Moghaddam, José Martínez Fernández, Cristian Mattar Bader, Renato Morbidelli, Jan P. Musial, Elise Osenga, Michael A. Palecki, Thierry Pellarin, George P. Petropoulos, Isabella Pfeil, Jarrett Powers, Alan Robock, Christoph Rüdiger, Udo Rummel, Michael Strobel, Zhongbo Su, Ryan Sullivan, Torbern Tagesson, Andrej Varlagin, Mariette Vreugdenhil, Jeffrey Walker, Jun Wen, Fred Wenger, Jean Pierre Wigneron, Mel Woods, Kun Yang, Yijian Zeng, Xiang Zhang, Marek Zreda, Stephan Dietrich, Alexander Gruber, Peter van Oevelen, Wolfgang Wagner, Klaus Scipal, Matthias Drusch, and Roberto Sabia
Hydrol. Earth Syst. Sci., 25, 5749–5804,Short summary
The International Soil Moisture Network (ISMN) is a community-based open-access data portal for soil water measurements taken at the ground and is accessible at https://ismn.earth. Over 1000 scientific publications and thousands of users have made use of the ISMN. The scope of this paper is to inform readers about the data and functionality of the ISMN and to provide a review of the scientific progress facilitated through the ISMN with the scope to shape future research and operations.
Clément Albergel, Yongjun Zheng, Bertrand Bonan, Emanuel Dutra, Nemesio Rodríguez-Fernández, Simon Munier, Clara Draper, Patricia de Rosnay, Joaquin Muñoz-Sabater, Gianpaolo Balsamo, David Fairbairn, Catherine Meurey, and Jean-Christophe Calvet
Hydrol. Earth Syst. Sci., 24, 4291–4316,Short summary
LDAS-Monde is a global offline land data assimilation system (LDAS) that jointly assimilates satellite-derived observations of surface soil moisture (SSM) and leaf area index (LAI) into the ISBA (Interaction between Soil Biosphere and Atmosphere) land surface model (LSM). This study demonstrates that LDAS-Monde is able to detect, monitor and forecast the impact of extreme weather on land surface states.
Yongjun Zheng, Clément Albergel, Simon Munier, Bertrand Bonan, and Jean-Christophe Calvet
Geosci. Model Dev., 13, 3607–3625,Short summary
This study proposes a sophisticated dynamically running job scheme as well as an innovative parallel IO algorithm to reduce the time to solution of an offline framework for high-dimensional ensemble Kalman filters. The offline and online modes of ensemble Kalman filters are built to comprehensively assess their time to solution efficiencies. The offline mode is substantially faster than the online mode in terms of time to solution, especially for large-scale assimilation problems.
Bertrand Bonan, Clément Albergel, Yongjun Zheng, Alina Lavinia Barbu, David Fairbairn, Simon Munier, and Jean-Christophe Calvet
Hydrol. Earth Syst. Sci., 24, 325–347,Short summary
This paper introduces an ensemble square root filter (EnSRF), a deterministic ensemble Kalman filter, for jointly assimilating observations of the surface soil moisture and leaf area index in the Land Data Assimilation System LDAS-Monde. LDAS-Monde constrains the Interaction between Soil, Biosphere and Atmosphere (ISBA) land surface model to improve the reanalysis of land surface variables. EnSRF is compared with the simplified extended Kalman filter over the European Mediterranean region.
Sibo Zhang, Catherine Meurey, and Jean-Christophe Calvet
Atmos. Chem. Phys., 19, 5005–5020,Short summary
In situ rain temperature measurements are rare. Soil moisture and soil temperature observations in southern France are used to assess the cooling effects on soils of rainfall events. The rainwater temperature is estimated using observed changes of topsoil volumetric soil moisture and soil temperature in response to the rainfall event. The obtained rain temperature estimates are generally lower than the ambient air temperatures, wet-bulb temperatures, and topsoil temperatures.
Clement Albergel, Emanuel Dutra, Simon Munier, Jean-Christophe Calvet, Joaquin Munoz-Sabater, Patricia de Rosnay, and Gianpaolo Balsamo
Hydrol. Earth Syst. Sci., 22, 3515–3532,Short summary
ECMWF recently released the first 7-year segment of its latest atmospheric reanalysis: ERA-5 (2010–2016). ERA-5 has important changes relative to ERA-Interim including higher spatial and temporal resolutions as well as a more recent model and data assimilation system. ERA-5 is foreseen to replace ERA-Interim reanalysis. One of the main goals of this study is to assess whether ERA-5 can enhance the simulation performances with respect to ERA-Interim when it is used to force a land surface model.
Emiliano Gelati, Bertrand Decharme, Jean-Christophe Calvet, Marie Minvielle, Jan Polcher, David Fairbairn, and Graham P. Weedon
Hydrol. Earth Syst. Sci., 22, 2091–2115,Short summary
We compared land surface model simulations forced by several meteorological datasets with observations over the Euro-Mediterranean area, for the 1979–2012 period. Precipitation was the most uncertain forcing variable. The impacts of forcing uncertainty were larger on the mean and standard deviation rather than the timing, shape and inter-annual variability of simulated discharge. Simulated leaf area index and surface soil moisture were relatively insensitive to these uncertainties.
Sibo Zhang, Jean-Christophe Calvet, José Darrozes, Nicolas Roussel, Frédéric Frappart, and Gilles Bouhours
Hydrol. Earth Syst. Sci., 22, 1931–1946,Short summary
Surface soil moisture was retrieved from a grassland site in southwestern France using the GNSS-IR technique. In order to efficiently limit the impact of perturbing vegetation effects, the grass growth period and the senescence period are treated separately. While the vegetation biomass effect can be corrected for, the litter water interception influences the observations and cannot be easily accounted for.
Clément Albergel, Simon Munier, Delphine Jennifer Leroux, Hélène Dewaele, David Fairbairn, Alina Lavinia Barbu, Emiliano Gelati, Wouter Dorigo, Stéphanie Faroux, Catherine Meurey, Patrick Le Moigne, Bertrand Decharme, Jean-Francois Mahfouf, and Jean-Christophe Calvet
Geosci. Model Dev., 10, 3889–3912,Short summary
LDAS-Monde, a global land data assimilation system, is applied over Europe and the Mediterranean basin to increase monitoring accuracy for land surface variables. It is able to ingest information from satellite-derived surface soil moisture (SSM) and leaf area index (LAI) observations to constrain the ISBA land surface model coupled with the CTRIP continental hydrological system. Assimilation of SSM and LAI leads to a better representation of evapotranspiration and gross primary production.
Hélène Dewaele, Simon Munier, Clément Albergel, Carole Planque, Nabil Laanaia, Dominique Carrer, and Jean-Christophe Calvet
Hydrol. Earth Syst. Sci., 21, 4861–4878,Short summary
Soil maximum available water content (MaxAWC) is a key parameter in land surface models. Being difficult to measure, this parameter is usually unavailable. A 15-year time series of satellite-derived observations of leaf area index (LAI) is used to retrieve MaxAWC for rainfed straw cereals over France. Disaggregated LAI is sequentially assimilated into the ISBA LSM. MaxAWC is estimated minimising LAI analyses increments. Annual maximum LAI observations correlate with the MaxAWC estimates.
Jaap Schellekens, Emanuel Dutra, Alberto Martínez-de la Torre, Gianpaolo Balsamo, Albert van Dijk, Frederiek Sperna Weiland, Marie Minvielle, Jean-Christophe Calvet, Bertrand Decharme, Stephanie Eisner, Gabriel Fink, Martina Flörke, Stefanie Peßenteiner, Rens van Beek, Jan Polcher, Hylke Beck, René Orth, Ben Calton, Sophia Burke, Wouter Dorigo, and Graham P. Weedon
Earth Syst. Sci. Data, 9, 389–413,Short summary
The dataset combines the results of 10 global models that describe the global continental water cycle. The data can be used as input for water resources studies, flood frequency studies etc. at different scales from continental to medium-scale catchments. We compared the results with earth observation data and conclude that most uncertainties are found in snow-dominated regions and tropical rainforest and monsoon regions.
David Fairbairn, Alina Lavinia Barbu, Adrien Napoly, Clément Albergel, Jean-François Mahfouf, and Jean-Christophe Calvet
Hydrol. Earth Syst. Sci., 21, 2015–2033,Short summary
This study assesses the impact on river discharge simulations over France of assimilating ASCAT-derived surface soil moisture (SSM) and leaf area index (LAI) observations into the ISBA land surface model. Wintertime LAI has a notable impact on river discharge. SSM assimilation degrades river discharge simulations. This is caused by limitations in the simplified versions of the Kalman filter and ISBA model used in this study. Implementing an observation operator for ASCAT is needed.
Jean-Christophe Calvet, Noureddine Fritz, Christine Berne, Bruno Piguet, William Maurel, and Catherine Meurey
SOIL, 2, 615–629,Short summary
Soil thermal conductivity in wet conditions can be retrieved together with the soil quartz content using a reverse modelling technique based on sub-hourly soil temperature observations at three depths below the soil surface. A pedotransfer function is proposed for quartz, for the considered region in France. Gravels have a major impact on soil thermal conductivity, and omitting the soil organic matter information tends to enhance this impact.
Roland Séférian, Christine Delire, Bertrand Decharme, Aurore Voldoire, David Salas y Melia, Matthieu Chevallier, David Saint-Martin, Olivier Aumont, Jean-Christophe Calvet, Dominique Carrer, Hervé Douville, Laurent Franchistéguy, Emilie Joetzjer, and Séphane Sénési
Geosci. Model Dev., 9, 1423–1453,Short summary
This paper presents the first IPCC-class Earth system model developed at Centre National de Recherches Météorologiques (CNRM-ESM1). We detail how the various carbon reservoirs were initialized and analyze the behavior of the carbon cycle and its prominent physical drivers, comparing model results to the most up-to-date climate and carbon cycle dataset over the latest decades.
D. Fairbairn, A. L. Barbu, J.-F. Mahfouf, J.-C. Calvet, and E. Gelati
Hydrol. Earth Syst. Sci., 19, 4811–4830,Short summary
The ensemble Kalman filter (EnKF) and simplified extended Kalman filter (SEKF) root-zone soil moisture analyses are compared when assimilating in situ surface observations. In the synthetic experiments, the EnKF performs best because it can stochastically capture the errors in the precipitation. The two methods perform similarly in the real experiments. During the summer period, both methods perform poorly as a result of nonlinearities in the land surface model.
S. Garrigues, A. Olioso, D. Carrer, B. Decharme, J.-C. Calvet, E. Martin, S. Moulin, and O. Marloie
Geosci. Model Dev., 8, 3033–3053,Short summary
This paper investigates the impacts of uncertainties in the climate, the vegetation dynamic, the soil properties and the cropland management on the simulation of evapotranspiration from the ISBA-A-gs land surface model over a 12-year Mediterranean crop succession. It mainly shows that errors in the soil parameters and the lack of irrigation in the simulation have the largest influence on evapotranspiration compared to the uncertainties in the climate and the vegetation dynamic.
S. Garrigues, A. Olioso, J. C. Calvet, E. Martin, S. Lafont, S. Moulin, A. Chanzy, O. Marloie, S. Buis, V. Desfonds, N. Bertrand, and D. Renard
Hydrol. Earth Syst. Sci., 19, 3109–3131,Short summary
Land surface model simulations of evapotranspiration are assessed over a 12-year Mediterranean crop succession. Evapotranspiration mainly results from soil evaporation when it is simulated over a Mediterranean crop succession. This leads to a high sensitivity to the soil parameters. Errors on soil hydraulic properties can lead to a large bias in cumulative evapotranspiration over a long period of time. Accounting for uncertainties in soil properties is essential for land surface modelling.
N. Canal, J.-C. Calvet, B. Decharme, D. Carrer, S. Lafont, and G. Pigeon
Hydrol. Earth Syst. Sci., 18, 4979–4999,Short summary
Regional French agricultural yield statistics are used to benchmark root water uptake representations in the ISBA-A-gs model. Key model parameters governing the inter-annual variability of the simulated biomass are retrieved. A complex multi-layer soil hydrology model does not outperform a simple bulk root-zone reservoir approach. This could be explained by missing processes/information in the model such as hydraulic redistribution and detailed soil properties.
E. Joetzjer, C. Delire, H. Douville, P. Ciais, B. Decharme, R. Fisher, B. Christoffersen, J. C. Calvet, A. C. L. da Costa, L. V. Ferreira, and P. Meir
Geosci. Model Dev., 7, 2933–2950,
M. Balzarolo, S. Boussetta, G. Balsamo, A. Beljaars, F. Maignan, J.-C. Calvet, S. Lafont, A. Barbu, B. Poulter, F. Chevallier, C. Szczypta, and D. Papale
Biogeosciences, 11, 2661–2678,
C. Szczypta, J.-C. Calvet, F. Maignan, W. Dorigo, F. Baret, and P. Ciais
Geosci. Model Dev., 7, 931–946,
M. Parrens, J.-F. Mahfouf, A. L. Barbu, and J.-C. Calvet
Hydrol. Earth Syst. Sci., 18, 673–689,
A. L. Barbu, J.-C. Calvet, J.-F. Mahfouf, and S. Lafont
Hydrol. Earth Syst. Sci., 18, 173–192,
L. Seoane, G. Ramillien, F. Frappart, and M. Leblanc
Hydrol. Earth Syst. Sci., 17, 4925–4939,
V. Masson, P. Le Moigne, E. Martin, S. Faroux, A. Alias, R. Alkama, S. Belamari, A. Barbu, A. Boone, F. Bouyssel, P. Brousseau, E. Brun, J.-C. Calvet, D. Carrer, B. Decharme, C. Delire, S. Donier, K. Essaouini, A.-L. Gibelin, H. Giordani, F. Habets, M. Jidane, G. Kerdraon, E. Kourzeneva, M. Lafaysse, S. Lafont, C. Lebeaupin Brossier, A. Lemonsu, J.-F. Mahfouf, P. Marguinaud, M. Mokhtari, S. Morin, G. Pigeon, R. Salgado, Y. Seity, F. Taillefer, G. Tanguy, P. Tulet, B. Vincendon, V. Vionnet, and A. Voldoire
Geosci. Model Dev., 6, 929–960,
R. Amri, M. Zribi, Z. Lili-Chabaane, C. Szczypta, J. C. Calvet, and G. Boulet
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript not accepted
Related subject area
Subject: Hydrometeorology | Techniques and Approaches: Instruments and observation techniquesAssessing KDP-based QPE for the record-breaking rainfall over Zhengzhou city on 20 July 2021Multi-scale temporal analysis of evaporation on a saline lake in the Atacama DesertCoastal and orographic effects on extreme precipitation revealed by weather radar observationsUnshielded precipitation gauge collection efficiency with wind speed and hydrometeor fall velocityEvaluation of Integrated Nowcasting through Comprehensive Analysis (INCA) precipitation analysis using a dense rain-gauge network in southeastern AustriaMicrophysical features of typhoon and non-typhoon rainfall observed in Taiwan, an island in the northwestern PacificPartial energy balance closure of eddy covariance evaporation measurements using concurrent lysimeter observations over grasslandRivers in the sky, flooding on the ground: the role of atmospheric rivers in inland flooding in central EuropeEvaluation of the WMO Solid Precipitation Intercomparison Experiment (SPICE) transfer functions for adjusting the wind bias in solid precipitation measurementsRainfall estimation from a German-wide commercial microwave link network: optimized processing and validation for 1 year of dataRadar-based characterisation of heavy precipitation in the eastern Mediterranean and its representation in a convection-permitting modelEffect of disdrometer type on rain drop size distribution characterisation: a new dataset for south-eastern AustraliaQuantitative precipitation estimation with weather radar using a data- and information-based approachContinuous, near-real-time observations of water stable isotope ratios during rainfall and throughfall eventsRain erosivity map for Germany derived from contiguous radar rain dataCitizen science flow – an assessment of simple streamflow measurement methodsDaily evaluation of 26 precipitation datasets using Stage-IV gauge-radar data for the CONUSExploring the use of underground gravity monitoring to evaluate radar estimates of heavy rainfallThe CAMELS-CL dataset: catchment attributes and meteorology for large sample studies – Chile datasetPrecipitation characteristics and associated weather conditions on the eastern slopes of the Canadian Rockies during March–April 2015Dendrohydrology and water resources management in south-central Chile: lessons from the Río Imperial streamflow reconstructionComparison of precipitation measurements by OTT Parsivel2 and Thies LPM optical disdrometersObtaining sub-daily new snow density from automated measurements in high mountain regionsDeriving surface soil moisture from reflected GNSS signal observations from a grassland site in southwestern FranceTesting and development of transfer functions for weighing precipitation gauges in WMO-SPICETechnical note: Using distributed temperature sensing for Bowen ratio evaporation measurementsEvaluation of GPM IMERG Early, Late, and Final rainfall estimates using WegenerNet gauge data in southeastern AustriaThe 2010–2015 megadrought in central Chile: impacts on regional hydroclimate and vegetationMeasuring precipitation with a geolysimeterConvective rainfall in a dry climate: relations with synoptic systems and flash-flood generation in the Dead Sea regionWater-use dynamics of an alien-invaded riparian forest within the Mediterranean climate zone of the Western Cape, South AfricaImpact of rainfall spatial aggregation on the identification of debris flow occurrence thresholdsArea-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysisAnalysis of single-Alter-shielded and unshielded measurements of mixed and solid precipitation from WMO-SPICEAnalysing surface energy balance closure and partitioning over a semi-arid savanna FLUXNET site in Skukuza, Kruger National Park, South AfricaRainfall and streamflow sensor network design: a review of applications, classification, and a proposed frameworkThe quantification and correction of wind-induced precipitation measurement errorsResponse of water vapour D-excess to land–atmosphere interactions in a semi-arid environmentAreal rainfall estimation using moving cars – computer experiments including hydrological modelingRecent changes and drivers of the atmospheric evaporative demand in the Canary IslandsA radar-based regional extreme rainfall analysis to derive the thresholds for a novel automatic alert system in SwitzerlandMaking rainfall features fun: scientific activities for teaching children aged 5–12 yearsEstimating evaporation with thermal UAV data and two-source energy balance modelsSpatio-temporal assessment of WRF, TRMM and in situ precipitation data in a tropical mountain environment (Cordillera Blanca, Peru)Historical changes in frequency of extreme floods in PragueSoil moisture–precipitation coupling: observations from the Oklahoma Mesonet and underlying physical mechanismsA comprehensive filtering scheme for high-resolution estimation of the water balance components from high-precision lysimetersInvestigating temporal field sampling strategies for site-specific calibration of three soil moisture–neutron intensity parameterisation methodsExtending periodic eddy covariance latent heat fluxes through tree sap-flow measurements to estimate long-term total evaporation in a peat swamp forestActual evapotranspiration and precipitation measured by lysimeters: a comparison with eddy covariance and tipping bucket
Haoran Li, Dmitri Moisseev, Yali Luo, Liping Liu, Zheng Ruan, Liman Cui, and Xinghua Bao
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript under review for HESSShort summary
This extreme rainfall event occurred at Zhengzhou on 20 July 2021 is widely concerned, as it caused tremendous losses of both lives and properties. However, the evolution of areal rainfall is still not clear. In this study, Kdp observations were used for quantitatively estimating areal rainfall accumulation. Different estimation methods as well as QPE results were compared. We found that the selection of kdp estimation method has minimal impact on hourly rainfall accumulation.
Felipe Lobos-Roco, Oscar Hartogensis, Francisco Suárez, Ariadna Huerta-Viso, Imme Benedict, Alberto de la Fuente, and Jordi Vilà-Guerau de Arellano
Hydrol. Earth Syst. Sci., 26, 3709–3729,Short summary
This research brings a multi-scale temporal analysis of evaporation in a saline lake of the Atacama Desert. Our findings reveal that evaporation is controlled differently depending on the timescale. Evaporation is controlled sub-diurnally by wind speed, regulated seasonally by radiation and modulated interannually by ENSO. Our research extends our understanding of evaporation, contributing to improving the climate change assessment and efficiency of water management in arid regions.
Francesco Marra, Moshe Armon, and Efrat Morin
Hydrol. Earth Syst. Sci., 26, 1439–1458,Short summary
We present a new method for quantifying the probability of occurrence of extreme rainfall using radar data, and we use it to examine coastal and orographic effects on extremes. We identify three regimes, directly related to precipitation physical processes, which respond differently to these forcings. The methods and results are of interest for researchers and practitioners using radar for the analysis of extremes, risk managers, water resources managers, and climate change impact studies.
Jeffery Hoover, Michael E. Earle, Paul I. Joe, and Pierre E. Sullivan
Hydrol. Earth Syst. Sci., 25, 5473–5491,Short summary
Transfer functions with dependence on wind speed and precipitation fall velocity are evaluated alongside transfer functions with wind speed and temperature dependence for unshielded precipitation gauges. The transfer functions with fall velocity dependence reduced the RMSE of unshielded gauge measurements relative to the functions based on wind speed and temperature, demonstrating the importance of fall velocity for precipitation gauge collection efficiency and transfer functions.
Esmail Ghaemi, Ulrich Foelsche, Alexander Kann, and Jürgen Fuchsberger
Hydrol. Earth Syst. Sci., 25, 4335–4356,Short summary
We assess an operational merged gauge–radar precipitation product over a period of 12 years, using gridded precipitation fields from a dense gauge network (WegenerNet) in southeastern Austria. We analyze annual data, seasonal data, and extremes using different metrics. We identify individual events using a simple threshold based on the interval between two consecutive events and evaluate the events' characteristics in both datasets.
Jayalakshmi Janapati, Balaji Kumar Seela, Pay-Liam Lin, Meng-Tze Lee, and Everette Joseph
Hydrol. Earth Syst. Sci., 25, 4025–4040,Short summary
Typhoon (TY) and non-typhoon (NTY) rainy days in northern Taiwan summer seasons showed more large drops on NTY than TY rainy days. Relatively higher convective activity and drier conditions in NTY than TY lead to variations in microphysical characteristics between TY and NTY rainy days. The raindrop size distribution and kinetic energy relations assessed for TY and NTY rainfall can be useful for evaluating the radar rainfall estimation algorithms, cloud modeling, and rainfall erosivity studies.
Peter Widmoser and Dominik Michel
Hydrol. Earth Syst. Sci., 25, 1151–1163,Short summary
With respect to ongoing discussions about the causes of energy imbalance, a method for closing the latent heat flux gap based on lysimeter measurements is assessed at four measurement stations over grassland in humid and semiarid climates. The applied partial closure yields excellent adjustments of eddy covariance data as compared to results found in the literature. The method also allows a distinction between systematic and random deviation of eddy covariance and lysimeter measurements.
Monica Ionita, Viorica Nagavciuc, and Bin Guan
Hydrol. Earth Syst. Sci., 24, 5125–5147,Short summary
Analysis of the largest 10 floods in the lower Rhine, between 1817 and 2015, shows that all these extreme flood peaks have been preceded, up to 7 d in advance, by intense moisture transport from the tropical North Atlantic basin in the form of narrow bands also known as atmospheric rivers. The results presented in this study offer new insights regarding the importance of moisture transport as the driver of extreme flooding in the lower part of the Rhine catchment area.
Craig D. Smith, Amber Ross, John Kochendorfer, Michael E. Earle, Mareile Wolff, Samuel Buisán, Yves-Alain Roulet, and Timo Laine
Hydrol. Earth Syst. Sci., 24, 4025–4043,Short summary
During the World Meteorological Organization Solid Precipitation Intercomparison Experiment (SPICE), transfer functions were developed to adjust automated gauge measurements of solid precipitation for systematic bias due to wind. The transfer functions were developed by combining data from eight sites, attempting to make them more universally applicable in a range of climates. This analysis is an assessment of the performance of those transfer functions, using data collected when SPICE ended.
Maximilian Graf, Christian Chwala, Julius Polz, and Harald Kunstmann
Hydrol. Earth Syst. Sci., 24, 2931–2950,Short summary
Commercial microwave links (CMLs), which form large parts of the backhaul from the ubiquitous cellular communication networks, can be used to estimate path-integrated rainfall rates. This study presents the processing and evaluation of the largest CML data set to date, covering the whole of Germany with almost 4000 CMLs. The CML-derived rainfall information compares well to a standard precipitation data set from the German Meteorological Service, which combines radar and rain gauge data.
Moshe Armon, Francesco Marra, Yehouda Enzel, Dorita Rostkier-Edelstein, and Efrat Morin
Hydrol. Earth Syst. Sci., 24, 1227–1249,Short summary
Heavy precipitation events (HPEs), occurring around the globe, lead to natural hazards as well as to water resource recharge. Rainfall patterns during HPEs vary from one case to another and govern their effect. Thus, correct prediction of these patterns is crucial for coping with HPEs. However, the ability of weather models to generate such patterns is unclear. Here, we characterise rainfall patterns during HPEs based on weather radar data and evaluate weather model simulations of these events.
Adrien Guyot, Jayaram Pudashine, Alain Protat, Remko Uijlenhoet, Valentijn R. N. Pauwels, Alan Seed, and Jeffrey P. Walker
Hydrol. Earth Syst. Sci., 23, 4737–4761,Short summary
We characterised for the first time the rainfall microphysics for Southern Hemisphere temperate latitudes. Co-located instruments were deployed to provide information on the sampling effect and spatio-temporal variabilities at micro scales. Substantial differences were found across the instruments, increasing with increasing values of the rain rate. Specific relations for reflectivity–rainfall are presented together with related uncertainties for drizzle and stratiform and convective rainfall.
Malte Neuper and Uwe Ehret
Hydrol. Earth Syst. Sci., 23, 3711–3733,Short summary
In this study, we apply a data-driven approach to quantitatively estimate precipitation using weather radar data. The method is based on information theory concepts. It uses predictive relations expressed by empirical discrete probability distributions, which are directly derived from data rather than the standard deterministic functions.
Barbara Herbstritt, Benjamin Gralher, and Markus Weiler
Hydrol. Earth Syst. Sci., 23, 3007–3019,Short summary
We describe a novel technique for the precise, quasi real-time observation of water-stable isotopes in gross precipitation and throughfall from tree canopies in parallel. Various processes (e.g. rainfall intensity, evapotranspiration, exchange with ambient vapour) thereby control throughfall intensity and isotopic composition. The achieved temporal resolution now competes with common meteorological measurements, thus enabling new ways to employ water-stable isotopes in forested catchments.
Karl Auerswald, Franziska K. Fischer, Tanja Winterrath, and Robert Brandhuber
Hydrol. Earth Syst. Sci., 23, 1819–1832,Short summary
Radar rain data enable for the first time portraying the erosivity pattern with high spatial and temporal resolution. This allowed quantification of erosivity in Germany with unprecedented detail. Compared to previous estimates, erosivity has strongly increased and its seasonal distribution has changed, presumably due to climate change. As a consequence, erosion for some crops is 4 times higher than previously estimated.
Jeffrey C. Davids, Martine M. Rutten, Anusha Pandey, Nischal Devkota, Wessel David van Oyen, Rajaram Prajapati, and Nick van de Giesen
Hydrol. Earth Syst. Sci., 23, 1045–1065,Short summary
Wise management of water resources requires data. Nevertheless, the amount of water data being collected continues to decline. We evaluated potential citizen science approaches for measuring flows of headwater streams and springs. After selecting salt dilution as the preferred approach, we partnered with Nepali students to cost-effectively measure flows and water quality with smartphones at 264 springs and streams which provide crucial water supplies to the rapidly expanding Kathmandu Valley.
Hylke E. Beck, Ming Pan, Tirthankar Roy, Graham P. Weedon, Florian Pappenberger, Albert I. J. M. van Dijk, George J. Huffman, Robert F. Adler, and Eric F. Wood
Hydrol. Earth Syst. Sci., 23, 207–224,Short summary
We conducted a comprehensive evaluation of 26 precipitation datasets for the US using the Stage-IV gauge-radar dataset as a reference. The best overall performance was obtained by MSWEP V2.2, underscoring the importance of applying daily gauge corrections and accounting for reporting times. Our findings can be used as a guide to choose the most suitable precipitation dataset for a particular application.
Laurent Delobbe, Arnaud Watlet, Svenja Wilfert, and Michel Van Camp
Hydrol. Earth Syst. Sci., 23, 93–105,Short summary
In this study, we explore the use of an underground superconducting gravimeter as a new source of in situ observations for the evaluation of radar-based precipitation estimates. The comparison of radar and gravity time series over 15 years shows that short-duration intense rainfall events cause a rapid decrease in the measured gravity. Rainfall amounts can be derived from this decrease. The gravimeter allows capture of rainfall at a much larger spatial scale than a traditional rain gauge.
Camila Alvarez-Garreton, Pablo A. Mendoza, Juan Pablo Boisier, Nans Addor, Mauricio Galleguillos, Mauricio Zambrano-Bigiarini, Antonio Lara, Cristóbal Puelma, Gonzalo Cortes, Rene Garreaud, James McPhee, and Alvaro Ayala
Hydrol. Earth Syst. Sci., 22, 5817–5846,Short summary
CAMELS-CL provides a catchment dataset in Chile, including 516 catchment boundaries, hydro-meteorological time series, and 70 catchment attributes quantifying catchments' climatic, hydrological, topographic, geological, land cover and anthropic intervention features. By using CAMELS-CL, we characterise hydro-climatic regional variations, assess precipitation and potential evapotranspiration uncertainties, and analyse human intervention impacts on catchment response.
Julie M. Thériault, Ida Hung, Paul Vaquer, Ronald E. Stewart, and John W. Pomeroy
Hydrol. Earth Syst. Sci., 22, 4491–4512,Short summary
Precipitation events associated with rain and snow on the eastern slopes of the Rocky Mountains, Canada, are a critical aspect of the regional water cycle. The goal is to characterize the precipitation and weather conditions in the Kananaskis Valley, Alberta, during a field experiment. Mainly dense solid precipitation reached the surface and occurred during downslope and upslope conditions. The precipitation phase has critical implications on the severity of flooding events in the area.
Alfonso Fernández, Ariel Muñoz, Álvaro González-Reyes, Isabella Aguilera-Betti, Isadora Toledo, Paulina Puchi, David Sauchyn, Sebastián Crespo, Cristian Frene, Ignacio Mundo, Mauro González, and Raffaele Vignola
Hydrol. Earth Syst. Sci., 22, 2921–2935,Short summary
Short-term river discharge records hamper assessment of the severity of modern droughts in south-central Chile, making effective water management difficult. To support decision-making, we present a ~300-year tree-ring reconstruction of summer discharge for this region. Results show that since 1980, droughts have become more frequent and are related to a shift in large-scale climate. We argue that water managers should use this long-term view to better allocate water rights.
Marta Angulo-Martínez, Santiago Beguería, Borja Latorre, and María Fernández-Raga
Hydrol. Earth Syst. Sci., 22, 2811–2837,Short summary
Two optical disdrometers, OTT Parsivel2 disdrometer and Thies Clima laser precipitation monitor (LPM), are compared. Analysis of 2 years of one-minute replicated data showed significant differences. Thies LPM recorded a larger number of particles than Parsivel2 and a higher proportion of small particles, resulting in higher rain rates and amounts and differences in radar reflectivity and kinetic energy. Possible causes for these differences, and their practical consequences, are discussed.
Kay Helfricht, Lea Hartl, Roland Koch, Christoph Marty, and Marc Olefs
Hydrol. Earth Syst. Sci., 22, 2655–2668,Short summary
We calculated hourly new snow densities from automated measurements. This time interval reduces the influence of settling of the freshly deposited snow. We found an average new snow density of 68 kg m−3. The observed variability could not be described using different parameterizations, but a relationship to temperature is partly visible at hourly intervals. Wind speed is a crucial parameter for the inter-station variability. Our findings are relevant for snow models working on hourly timescales.
Sibo Zhang, Jean-Christophe Calvet, José Darrozes, Nicolas Roussel, Frédéric Frappart, and Gilles Bouhours
Hydrol. Earth Syst. Sci., 22, 1931–1946,Short summary
Surface soil moisture was retrieved from a grassland site in southwestern France using the GNSS-IR technique. In order to efficiently limit the impact of perturbing vegetation effects, the grass growth period and the senescence period are treated separately. While the vegetation biomass effect can be corrected for, the litter water interception influences the observations and cannot be easily accounted for.
John Kochendorfer, Rodica Nitu, Mareile Wolff, Eva Mekis, Roy Rasmussen, Bruce Baker, Michael E. Earle, Audrey Reverdin, Kai Wong, Craig D. Smith, Daqing Yang, Yves-Alain Roulet, Tilden Meyers, Samuel Buisan, Ketil Isaksen, Ragnar Brækkan, Scott Landolt, and Al Jachcik
Hydrol. Earth Syst. Sci., 22, 1437–1452,Short summary
Due to the effects of wind, precipitation gauges typically underestimate the amount of precipitation that occurs as snow. Measurements recorded during a World Meteorological Organization intercomparison of precipitation gauges were used to evaluate and improve the adjustments that are available to address this issue. Adjustments for specific types of precipitation gauges and wind shields were tested and recommended.
Bart Schilperoort, Miriam Coenders-Gerrits, Willem Luxemburg, César Jiménez Rodríguez, César Cisneros Vaca, and Hubert Savenije
Hydrol. Earth Syst. Sci., 22, 819–830,Short summary
DTStechnology, we measured the evaporation of a forest using fibre optic cables. The cables work like long thermometers, with a measurement every 12.5 cm. We placed the cables vertically along the tower, one cable being dry, the other kept wet. By looking at the dry and wet cable temperatures over the height we are able to study heat storage and the amount of water the forest is evaporating. These results can be used to better understand the storage and heat exchange of forests.
Sungmin O, Ulrich Foelsche, Gottfried Kirchengast, Juergen Fuchsberger, Jackson Tan, and Walter A. Petersen
Hydrol. Earth Syst. Sci., 21, 6559–6572,Short summary
We evaluate gridded satellite rainfall estimates, from GPM IMERG, through a direct grid-to-grid comparison with gauge data from the WegenerNet Feldbach (WEGN) network in southeastern Austria. As the WEGN data are independent of the IMERG gauge adjustment process, we could analyze the IMERG estimates across its three different runs. Our results show the effects of additional retrieval processes on the final rainfall estimates, and consequently provide IMERG accuracy information for data users.
René D. Garreaud, Camila Alvarez-Garreton, Jonathan Barichivich, Juan Pablo Boisier, Duncan Christie, Mauricio Galleguillos, Carlos LeQuesne, James McPhee, and Mauricio Zambrano-Bigiarini
Hydrol. Earth Syst. Sci., 21, 6307–6327,Short summary
This work synthesizes an interdisciplinary research on the megadrought (MD) that has afflicted central Chile since 2010. Although 1- or 2-year droughts are not infrequent in this Mediterranean-like region, the ongoing dry period stands out because of its longevity and large extent, leading to unseen hydrological effects and vegetation impacts. Understanding the nature and biophysical impacts of the MD contributes to confronting a dry, warm future regional climate scenario in subtropical regions.
Craig D. Smith, Garth van der Kamp, Lauren Arnold, and Randy Schmidt
Hydrol. Earth Syst. Sci., 21, 5263–5272,Short summary
This research provides an example of how groundwater pressures measured in deep observation wells can be used as a reliable estimate, and perhaps as a reference, for event-based precipitation. Changes in loading at the surface due to the weight of precipitation are transferred to the groundwater formation and can be measured in the observation well. Correlations in precipitation measurements made with the
geolysimeterand the co-located sheltered precipitation gauge are high.
Idit Belachsen, Francesco Marra, Nadav Peleg, and Efrat Morin
Hydrol. Earth Syst. Sci., 21, 5165–5180,Short summary
Spatiotemporal rainfall patterns in arid environments are not well-known. We derived properties of convective rain cells over the arid Dead Sea region from a long-term radar archive. We found differences in cell properties between synoptic systems and between flash-flood and non-flash-flood events. Large flash floods are associated with slow rain cells, directed downstream with the main catchment axis. Results from this work can be used for hydrological models and stochastic storm simulations.
Bruce C. Scott-Shaw, Colin S. Everson, and Alistair D. Clulow
Hydrol. Earth Syst. Sci., 21, 4551–4562,Short summary
In South Africa, the invasion of riparian forests by alien trees has the potential to affect the limited water resources. To justify alien clearing programs, hydrological benefits are required. Spatial upscaling of measured sapflows showed that an alien stand used 6 times more water per unit area than the indigenous stand. A gain in groundwater recharge and/or streamflow would be achieved if the alien species were removed from riparian forests and rehabilitated back to their natural state.
Francesco Marra, Elisa Destro, Efthymios I. Nikolopoulos, Davide Zoccatelli, Jean Dominique Creutin, Fausto Guzzetti, and Marco Borga
Hydrol. Earth Syst. Sci., 21, 4525–4532,Short summary
Previous studies have reported a systematic underestimation of debris flow occurrence thresholds, due to the use of sparse networks in non-stationary rain fields. We analysed high-resolution radar data to show that spatially aggregated estimates (e.g. satellite data) largely reduce this issue, in light of a reduced estimation variance. Our findings are transferable to other situations in which lower envelope curves are used to predict point-like events in the presence of non-stationary fields.
Feinan Xu, Weizhen Wang, Jiemin Wang, Ziwei Xu, Yuan Qi, and Yueru Wu
Hydrol. Earth Syst. Sci., 21, 4037–4051,
John Kochendorfer, Rodica Nitu, Mareile Wolff, Eva Mekis, Roy Rasmussen, Bruce Baker, Michael E. Earle, Audrey Reverdin, Kai Wong, Craig D. Smith, Daqing Yang, Yves-Alain Roulet, Samuel Buisan, Timo Laine, Gyuwon Lee, Jose Luis C. Aceituno, Javier Alastrué, Ketil Isaksen, Tilden Meyers, Ragnar Brækkan, Scott Landolt, Al Jachcik, and Antti Poikonen
Hydrol. Earth Syst. Sci., 21, 3525–3542,Short summary
Precipitation measurements were combined from eight separate precipitation testbeds to create multi-site transfer functions for the correction of unshielded and single-Alter-shielded precipitation gauge measurements. Site-specific errors and more universally applicable corrections were created from these WMO-SPICE measurements. The importance and magnitude of such wind speed corrections were demonstrated.
Nobuhle P. Majozi, Chris M. Mannaerts, Abel Ramoelo, Renaud Mathieu, Alecia Nickless, and Wouter Verhoef
Hydrol. Earth Syst. Sci., 21, 3401–3415,Short summary
The study analysed the quality and partitioning of a 15-year surface energy dataset from Skukuza flux tower. The yearly mean energy balance ratio (EBR) was 0.93, with the dry season having the lowest ratio. Night ratio was lower than daytime, with analysis showing an increase in EBR with increase in friction velocity, which is also linked to time of day. The energy partitioning showed that sensible heat flux is the dominant portion in the dry season, and latent heat flux during the wet season.
Juan C. Chacon-Hurtado, Leonardo Alfonso, and Dimitri P. Solomatine
Hydrol. Earth Syst. Sci., 21, 3071–3091,Short summary
This paper compiles most of the studies (as far as the authors are aware) on the design of sensor networks for measurement of precipitation and streamflow. The literature shows that there is no overall consensus on the methods for the evaluation of sensor networks, as different design criteria often lead to different solutions. This paper proposes a methodology for the classification of methods, and a general framework for the design of sensor networks.
John Kochendorfer, Roy Rasmussen, Mareile Wolff, Bruce Baker, Mark E. Hall, Tilden Meyers, Scott Landolt, Al Jachcik, Ketil Isaksen, Ragnar Brækkan, and Ronald Leeper
Hydrol. Earth Syst. Sci., 21, 1973–1989,Short summary
Snowfall measurements recorded using precipitation gauges are subject to significant underestimation due to the effects of wind. Using measurements recorded at two different precipitation test beds, corrections for unshielded gauges and gauges within different types of windshields were developed and tested. Using the new corrections, uncorrectable errors were quantified, and measurement biases were successfully eliminated.
Stephen D. Parkes, Matthew F. McCabe, Alan D. Griffiths, Lixin Wang, Scott Chambers, Ali Ershadi, Alastair G. Williams, Josiah Strauss, and Adrian Element
Hydrol. Earth Syst. Sci., 21, 533–548,Short summary
Determining atmospheric moisture sources is required for understanding the water cycle. The role of land surface fluxes is a particular source of uncertainty for moisture budgets. Water vapour isotopes have the potential to improve constraints on moisture sources. In this work relationships between water vapour isotopes and land–atmosphere exchange are studied. Results show that land surface evaporative fluxes play a minor role in the daytime water and isotope budgets in semi-arid environments.
Ehsan Rabiei, Uwe Haberlandt, Monika Sester, Daniel Fitzner, and Markus Wallner
Hydrol. Earth Syst. Sci., 20, 3907–3922,Short summary
The value of using moving cars for rainfall measurement purposes (RCs) was investigated with laboratory experiments by Rabiei et al. (2013). They analyzed the Hydreon and Xanonex optical sensors against different rainfall intensities. A continuous investigation of using RCs with the derived uncertainties from laboratory experiments for areal rainfall estimation as well as implementing the data in a hydrological model are addressed in this study.
Sergio M. Vicente-Serrano, Cesar Azorin-Molina, Arturo Sanchez-Lorenzo, Ahmed El Kenawy, Natalia Martín-Hernández, Marina Peña-Gallardo, Santiago Beguería, and Miquel Tomas-Burguera
Hydrol. Earth Syst. Sci., 20, 3393–3410,Short summary
In this work we analyse the recent evolution and meteorological drivers of the atmospheric evaporative demand in the Canary Islands. We found that the reference evapotranspiration increased by 18.2 mm decade−1 – on average – between 1961 and 2013, with the highest increase recorded during summer. This increase was mainly driven by changes in the aerodynamic component, caused by a statistically significant reduction of the relative humidity.
Luca Panziera, Marco Gabella, Stefano Zanini, Alessandro Hering, Urs Germann, and Alexis Berne
Hydrol. Earth Syst. Sci., 20, 2317–2332,Short summary
This paper presents a novel system to issue heavy rainfall alerts for predefined geographical regions by evaluating the sum of precipitation fallen in the immediate past and expected in the near future. In order to objectively define the thresholds for the alerts, an extreme rainfall analysis for the 159 regions used for official warnings in Switzerland was developed. It is shown that the system has additional lead time with respect to thunderstorm tracking tools targeted for convective storms.
Auguste Gires, Catherine L. Muller, Marie-Agathe le Gueut, and Daniel Schertzer
Hydrol. Earth Syst. Sci., 20, 1751–1763,Short summary
Educational activities are now a common channel to increase impact of research projects. Here, we present innovative activities for young children that aim to help them (and their teachers) grasp some of the complex underlying scientific issues in environmental fields. The activities developed are focused on rainfall: observation and modeling of rain drop size and the succession of dry and rainy days, and writing of a scientific book. All activities were implemented in classrooms.
H. Hoffmann, H. Nieto, R. Jensen, R. Guzinski, P. Zarco-Tejada, and T. Friborg
Hydrol. Earth Syst. Sci., 20, 697–713,Short summary
Thermal images collected with an unmanned aerial vehicle (UAV) are applied to algorithms originally developed to be operational with satellite images, in order to estimate evapotranspiration in very high resolution. It is concluded that the thermal UAV data can be used for model input and for other potential applications requiring good quality, consistent, and high resolution land surface temperature.
L. Mourre, T. Condom, C. Junquas, T. Lebel, J. E. Sicart, R. Figueroa, and A. Cochachin
Hydrol. Earth Syst. Sci., 20, 125–141,Short summary
Three different types of gridded precipitation products are compared in a high glaciated tropical mountain environment (Cordillera Blanca, Peru): ground-based interpolation, a satellite-derived product (TRMM3B42), and outputs from the WRF regional climate model. While none of the products meets the challenge of representing both accumulated quantities and frequency of occurrence at the short timescale, we concluded that new methods should be used to merge those various precipitation products.
Hydrol. Earth Syst. Sci., 19, 4307–4315,Short summary
A flood frequency analysis for the Vltava River catchment based on an interpretation of documentary sources was carried out for a major profile in Prague. Six flood-rich periods in total were identified for 1118–2013. The most important were in the 16th and 19th centuries. The territory of the present Czech Republic might have experienced in the past, extreme floods comparable, with regard to peak discharge (higher than or equal to Q10) and frequency, to the flood events recorded recently.
T. W. Ford, A. D. Rapp, S. M. Quiring, and J. Blake
Hydrol. Earth Syst. Sci., 19, 3617–3631,Short summary
We combine in situ soil moisture observations with radar-derived precipitation to evaluate soil moisture feedback on convective rainfall in the US Southern Great Plains. We find strong connections between morning soil moisture and atmospheric conditions including boundary layer height, surface temperature, and relative humidity at the boundary layer top. The results of this study demonstrate both positive and negative soil moisture feedbacks are important in this region of the USA.
M. Hannes, U. Wollschläger, F. Schrader, W. Durner, S. Gebler, T. Pütz, J. Fank, G. von Unold, and H.-J. Vogel
Hydrol. Earth Syst. Sci., 19, 3405–3418,
J. Iwema, R. Rosolem, R. Baatz, T. Wagener, and H. R. Bogena
Hydrol. Earth Syst. Sci., 19, 3203–3216,Short summary
The cosmic-ray neutron sensor can provide soil moisture content averages over areas of roughly half a kilometre by half a kilometre. Although this sensor is usually calibrated using soil samples taken on a single day, we found that multiple sampling days are needed. The calibration results were also affected by the soil wetness conditions of the sampling days. The outcome of this study will help researchers to calibrate/validate new cosmic-ray neutron sensor sites more accurately.
A. D. Clulow, C. S. Everson, M. G. Mengistu, J. S. Price, A. Nickless, and G. P. W. Jewitt
Hydrol. Earth Syst. Sci., 19, 2513–2534,Short summary
The 3rd paper in a series dealing with evaporation over indigenous vegetation in an area of South Africa experiencing severe water challenges. The area is a World Heritage site and an important conservation area in which our understanding of the water balance plays a crucial role in system management. We provide the fist estimates of total evaporation from a subtropical peat swamp forest, investigate measurement techniques and provide modelling solutions to estimate long-term evaporation.
S. Gebler, H.-J. Hendricks Franssen, T. Pütz, H. Post, M. Schmidt, and H. Vereecken
Hydrol. Earth Syst. Sci., 19, 2145–2161,
Albergel, C., Calvet, J. C., De Rosnay, P., Balsamo, G., Wagner, W., Hasenauer, S., Naeimi, V., Martin, E., Bazile, E., Bouyssel, F., and Mahfouf, J. F.: Cross-evaluation of modelled and remotely sensed surface soil moisture with in situ data in southwestern France, Hydrol. Earth Syst. Sci., 14, 2177–2191, https://doi.org/10.5194/hess-14-2177-2010, 2010.
Betbeder, J., Fieuzal, R., Philippets, Y., Ferro-Famil, L., and Baup, F.: Contribution of multitemporal polarimetric synthetic aperture radar data for monitoring winter wheat and rapeseed crops, J. Appl. Remote Sens., 10, 026020, https://doi.org/10.1117/1.JRS.10.026020, 2016.
Bilich, A. and Larson, K. M.: Mapping the GPS multipath environment using the signal-to-noise ratio (SNR), Radio Sci., 42, RS6003, https://doi.org/10.1029/2007RS003652, 2007.
Boniface, K., Braun, J. J., McCreight, J. L., and Nievinski, F. G.: Comparison of snow data assimilation system with GPS reflectometry snow depth in the western United States, Hydrol. Processe., 29, 2425–2437, https://doi.org/10.1002/hyp.10346, 2015.
Chan, S. K., Bindlish, R., O'Neill, P. E., Njoku, E., Jackson, T., Colliander, A., Chen, F., Burgin, M., Dunbar, S., Piepmeier, J., Yueh, S., Entekhabi, D., Cosh, M. H., Caldwell, T., Walker, J., Wu, X., Berg, A., Rowlandson, T., Pacheco, A., McNairn, H., Thibeault, M., Martínez-Fernández, J., González-Zamora, A., Seyfried, M., Bosch, D., Starks, P., Goodrich, D., Prueger, J., Palecki, M., Small, E. E., Zreda, M., Calvet, J.-C., Crow, W., and Kerr, Y.: Assessment of the SMAP passive soil moisture product, IEEE T. Geosci. Remote, 54, 4994–5007, https://doi.org/10.1109/TGRS.2016.2561938, 2016.
Chew, C. C., Small, E. E., Larson, K. M., and Zavorotny, V. U.: Effects of near-surface soil moisture on GPS SNR data: development of a retrieval algorithm for soil moisture, IEEE T. Geosci. Remote, 52, 537–543, https://doi.org/10.1109/TGRS.2013.2242332, 2014.
Chew, C. C., Small, E. E., Larson, K. M., and Zavorotny, V. U.: Vegetation sensing using GPS-interferometric reflectometry: theoretical effects of canopy parameters on signal-to-noise ratio data, IEEE T. Geosci. Remote, 53, 2755–2764, https://doi.org/10.1109/TGRS.2014.2364513, 2015.
Chew, C. C., Small, E. E., and Larson, K. M.: An algorithm for soil moisture estimation using GPS-interferometric reflectometry for bare and vegetated soil, GPS Solutions, 20, 525–537, https://doi.org/10.1007/s10291-015-0462-4, 2016.
Darrozes, J., Gaillot, P., De Saint-Blanquat, M., and Bouchez, J. L.: Software for multi-scale image analysis: The normalized optimized Anisotropic Wavelet Coefficient method, Comput. Geosci., 23, 889–895, https://doi.org/10.1016/S0098-3004(97)00063-0, 1997.
Decharme, B., Boone, A., Delire, C., and Noilhan, J.: Local evaluation of the Interaction between Soil Biosphere Atmosphere soil multilayer diffusion scheme using four pedotransfer functions, J. Geophys. Res., 116, D20126, https://doi.org/10.1029/2011JD016002, 2011.
Dorigo, W. A., Scipal, K., Parinussa, R. M., Liu, Y. Y., Wagner, W., de Jeu, R. A. M., and Naeimi, V.: Error characterisation of global active and passive microwave soil moisture datasets, Hydrol. Earth Syst. Sci., 14, 2605–2616, https://doi.org/10.5194/hess-14-2605-2010, 2010.
Dorigo, W. A., Xaver, A., Vreugdenhil, M., Gruber, A., Hegyiová, A., Sanchis-Dufau, A. D., Zamojski, D., Cordes, C., Wagner, W., and Drusch, M.: Global automated quality control of in situ soil moisture data from the International Soil Moisture Network, Vadose Zone J., 12, 21, https://doi.org/10.2136/vzj2012.0097, 2013.
Durand, Y., Brun, E., Merindol, L., Guyomarc'h, G., Lesaffre, B., and Martin, E.: A meteorological estimation of relevant parameters for snow models, Ann. Geophys., 18, 65–71, https://doi.org/10.1017/S0260305500011277, 1993.
Durand, Y., Giraud, G., Brun, E., Merindol, L., and Martin, E.: A computer-based system simulating snow-pack structures as a tool for regional avalanche forecasting, Ann. Glaciol., 45, 469–484, https://doi.org/10.1017/S0022143000001337, 1999.
Duveiller, G., Weiss, M., Baret, F., and Defourny, P.: Retrieving wheat green area index during the growing season from optical time series measurements based on neural network radiative transfer inversion, Remote Sens. Environ., 115, 887–896, https://doi.org/10.1016/j.rse.2010.11.016, 2011.
Escalera, E. and MacGillivray, H. T.: Topology in galaxy distributions: method for a multi-scale analysis. A use of the wavelet transform, Astron. Astrophys., 298, 1–21, 1995.
Fieuzal, R., Baup, F., and Marais-Sicre, C.: Monitoring wheat and rapeseed by using synchronous optical and radar satellite data – From temporal signatures to crop parameters estimation, Adv. Remote Sens., 2, 33222, https://doi.org/10.4236/ars.2013.22020, 2013.
Foti, G., Gommenginger, C., Jales, P., Unwin, M., Shaw, A., Robertson, C., and Rosello, J.: Spaceborne GNSS reflectometry for ocean winds: First results from the UK TechDemoSat-1 mission, Geophys. Res. Lett., 42, 5435–5441, https://doi.org/10.1002/2015GL064204, 2015.
Gaillot, P., Darrozes, J., and Bouchez, J. L.: Wavelet transform: a future of rock fabric analysis?, J. Struct. Geol., 21, 1615–1621, https://doi.org/10.1016/S0191-8141(99)00073-5, 1999.
Gastal, F. and Lemaire, G.: N uptake and distribution in crops: an agronomical and ecophysiological perspective, J. Exp. Bot., 53, 789–799, https://doi.org/10.1093/jexbot/53.370.789, 2002.
Georgiadou, Y. and Kleusberg, A.: On carrier signal multipath effects in relative GPS positioning, Manuscripta Geodaetica, 13, 172–179, 1988.
Grinsted, A., Moore, J. C., and Jevrejeva, S.: Application of the cross wavelet transform and wavelet coherence to geophysical time series, Nonlin. Processes Geophys., 11, 561–566, https://doi.org/10.5194/npg-11-561-2004, 2004.
Hagelberg, C. and Helland, J.: Thin-line detection in meteorological radar images using wavelet transforms, J. Atmos. Ocean. Tech., 12, 633–642, https://doi.org/10.1175/1520-0426(1995)012<0633:TLDIMR>2.0.CO;2, 1995.
Kerr, Y., Waldteufel, P., Wigneron, J., Martinuzzi, J., Font, J., and Berger, M.: Soil moisture retrieval from space: The Soil Moisture and Ocean Salinity (SMOS) mission, IEEE T. Geosci. Remote, 39, 1729–1735, https://doi.org/10.1109/36.942551, 2001.
Koch, F., Schlenz, F., Prasch, M., Appel, F., Ruf, T., and Mauser, W.: Soil Moisture Retrieval Based on GPS Signal Strength Attenuation, Water, 8, 276, https://doi.org/10.3390/w8070276, 2016.
Labat, D.: Recent advances in wavelet analyses: Part 1. A review of concepts, J. Hydrol., 314, 275–288, 2005.
Lafont, S., Zhao, Y., Calvet, J.-C., Peylin, P., Ciais, P., Maignan, F., and Weiss, M.: Modelling LAI, surface water and carbon fluxes at high-resolution over France: comparison of ISBA-A-gs and ORCHIDEE, Biogeosciences, 9, 439–456, https://doi.org/10.5194/bg-9-439-2012, 2012.
Larson, K. M.: GPS interferometric reflectometry: applications to surface soil moisture, snow depth, and vegetation water content in the western United States, Wiley Interdisciplin. Rev.: Water, 3, 775–787, https://doi.org/10.1002/wat2.1167, 2016.
Larson, K. M. and Nievinski, F. G.: GPS snow sensing: results from the EarthScope Plate Boundary Observatory, GPS Solutions, 17, 41–52, https://doi.org/10.1007/s10291-012-0259-7, 2013.
Larson, K. M. and Small, E. E.: Normalized microwave reflection index: A vegetation measurement derived from GPS networks, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 7, 1501–1511, https://doi.org/10.1109/JSTARS.2014.2300116, 2014.
Larson, K. M., Small, E. E., Gutmann, E. D., Bilich, A. L., Braun, J. J., and Zavorotny, V. U.: Use of GPS receivers as a soil moisture network for water cycle studies, Geophys. Res. Lett., 35, L24405, https://doi.org/10.1029/2008GL036013, 2008.
Larson, K. M., Braun, J. J., Small, E. E., Zavorotny, V. U., Gutmann, E. D., and Bilich, A. L.: GPS multipath and its relation to near-surface soil moisture content, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 3, 91–99, https://doi.org/10.1109/JSTARS.2009.2033612, 2010.
Larson, K. M., Small, E. E., Chew, C. C., Nievinski, F. G., Pratt, J., McCreight, J. L., Braun, J., Boniface, K., and Evans, S. G.: PBO H2O: Plate Boundary Observatory Studies of the Water Cycle, in: Fall Meeting, American Geophysical Union, 9–13 December 2013, San Francisco, 2013.
Masson, V., Le Moigne, P., Martin, E., Faroux, S., Alias, A., Alkama, R., Belamari, S., Barbu, A., Boone, A., Bouyssel, F., Brousseau, P., Brun, E., Calvet, J.-C., Carrer, D., Decharme, B., Delire, C., Donier, S., Essaouini, K., Gibelin, A.-L., Giordani, H., Habets, F., Jidane, M., Kerdraon, G., Kourzeneva, E., Lafaysse, M., Lafont, S., Lebeaupin Brossier, C., Lemonsu, A., Mahfouf, J.-F., Marguinaud, P., Mokhtari, M., Morin, S., Pigeon, G., Salgado, R., Seity, Y., Taillefer, F., Tanguy, G., Tulet, P., Vincendon, B., Vionnet, V., and Voldoire, A.: The SURFEXv7.2 land and ocean surface platform for coupled or offline simulation of earth surface variables and fluxes, Geosci. Model Dev., 6, 929–960, https://doi.org/10.5194/gmd-6-929-2013, 2013.
Morisette, J. T., Baret, F., Privette, J. L., Myneni, R. B., Nickeson, J. E., Garrigues, S., Shabanov, N., Weiss, M., Fernandes, R., Leblanc, S., Kalacska, M., Sánchez-Azofeifa, G. A., Chubey, M., Rivard, B., Stenberg, P., Rautiainen, M., Voipio, P., Manninen, T., Pilant, A. N., Lewis, T. E., Iiames, J. S., Colombo, R., Meroni, M., Busetto, L., Cohen, W., Turner, D.P ., Warner, E. D., Petersen, G. W., Seufert, G., and Cook, R.: Validation of global moderate-resolution LAI products: A framework proposed within the CEOS land product validation subgroup, IEEE T. Geosci. Remote, 44, 1804–1817, 2006.
Motte, E., Egido, A., Roussel, N., Boniface, K., Frappart, F., Baghdadi, N., and Zribi, M.: Applications of GNSS-R in continental hydrology, Land Surface Remote Sensing in Continental Hydrology, Elsevier, Amsterdam, the Netherlands, 281–321, https://doi.org/10.1016/B978-1-78548-104-8.50009-7, 2016.
Njoku, E. G., Wilson, W. J., Yueh, S. H., Dinardo, S. J., Li, F. K., Jackson, T. J., Lakshmi, V., and Bolten, J.: Observations of soil moisture using a passive and active low-frequency microwave airborne sensor during SGP99, IEEE T. Geosci. Remote, 40, 2659–2673, https://doi.org/10.1109/TGRS.2002.807008, 2002.
Ouillon, G., Sornette, D., and Castaing, C.: Organisation of joints and faults from 1-cm to 100-km scales revealed by optimized anisotropic wavelet coefficient method and multifractal analysis, Nonlin. Processes Geophys., 2, 158–177, https://doi.org/10.5194/npg-2-158-1995, 1995.
Roesch, A., Schmidbauer, H., and Roesch, M. A.: Package `WaveletComp', https://pbil.univ-lyon1.fr/CRAN/web/packages/WaveletComp/WaveletComp.pdf (last access: September 2017), 2014.
Roussel, N., Frappart, F., Ramillien, G., Darrozes, J., Desjardins, C., Gegout, P., Pérosanz, F., and Biancale, R.: Simulations of direct and reflected wave trajectories for ground-based GNSS-R experiments, Geosci. Model Dev., 7, 2261–2279, https://doi.org/10.5194/gmd-7-2261-2014, 2014.
Roussel, N., Frappart, F., Ramillien, G., Darrozes, J., Baup, F., Lestarquit, L., and Ha, M. C.: Detection of Soil Moisture Variations Using GPS and GLONASS SNR Data for Elevation Angles Ranging From 2° to 70°, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 9, 4781–4794, https://doi.org/10.1109/JSTARS.2016.2537847, 2016.
Small, E. E., Larson, K. M., and Braun, J. J.: Sensing vegetation growth with reflected GPS signals, Geophys. Res. Lett., 37, L12401, https://doi.org/10.1029/2010GL042951, 2010.
Small, E. E., Larson, K. M., and Smith, W. K.: Normalized microwave reflection index: validation of vegetation water content estimates from Montana grasslands, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 7, 1512–1521, https://doi.org/10.1109/JSTARS.2014.2320597, 2014.
Small, E. E., Larson, K. M., Chew, C. C., Dong, J., and Ochsner, T. E.: Validation of GPS-IR soil moisture retrievals: Comparison of different algorithms to remove vegetation effects, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 9, 4759–4770, https://doi.org/10.1109/JSTARS.2015.2504527, 2016.
Torrence, C. and Compo, G. P.: A practical guide to wavelet analysis, B. Am. Meteorol. Soc., 79, 61–78, https://doi.org/10.1175/1520-0477(1998)079<0061:APGTWA>2.0.CO;2, 1998.
Vey, S., Güntner, A., Wickert, J., Blume, T., and Ramatschi, M.: Long-term soil moisture dynamics derived from GNSS interferometric reflectometry: A case study for Sutherland, South Africa, GPS Solutions, 20, 641–654, https://doi.org/10.1007/s10291-015-0474-0, 2016.
Wan, W., Larson, K. M., Small, E. E., Chew, C. C., and Braun, J. J.: Using geodetic GPS receivers to measure vegetation water content, GPS Solutions, 19, 237–248, https://doi.org/10.1007/s10291-014-0383-7, 2015.
Wigneron, J. P., Ferrazzoli, P., Olioso, A., Bertuzzi, P., and Chanzy, A.: A simple approach to monitor crop biomass from C-band radar data, Remote Sens. Environ., 69, 179–188, https://doi.org/10.1016/S0034-4257(99)00011-5, 1999.
Wigneron, J. P., Chanzy, A., Calvet, J. C., Olioso, A., and Kerr, Y.: Modeling approaches to assimilating L band passive microwave observations over land surfaces, J. Geophys. Res.-Atmos., 107, 4219, https://doi.org/10.1029/2001JD000958, 2002.
Zavorotny, V. U., Larson, K. M., Braun, J. J., Small, E. E., Gutmann, E. D., and Bilich, A. L.: A physical model for GPS multipath caused by land reflections: Toward bare soil moisture retrievals, IEEE J. Select. Top. Appl. Earth Obs. Rem. Sens., 3, 100–110, https://doi.org/10.1109/JSTARS.2009.2033608, 2010.
Zavorotny, V. U., Gleason, S., Cardellach, E., and Camps, A.: Tutorial on remote sensing using GNSS bistatic radar of opportunity, IEEE Geosci. Rem. Sens. Mag., 2, 8–45, https://doi.org/10.1109/MGRS.2014.2374220, 2014.
GNSS SNR data were obtained from an intensively cultivated wheat field in southwestern France. The data were used to retrieve soil moisture and vegetation characteristics during the growing period of wheat. Vegetation growth broke up the constant height assumption used in soil moisture retrieval algorithms. Soil moisture could not be retrieved after wheat tillering. A new algorithm based on a wavelet analysis was implemented and used to retrieve vegetation height.
GNSS SNR data were obtained from an intensively cultivated wheat field in southwestern France....