Articles | Volume 18, issue 3
Research article 07 Mar 2014
Research article | 07 Mar 2014
Energy fluxes and surface characteristics over a cultivated area in Benin: daily and seasonal dynamics
O. Mamadou et al.
No articles found.
Clément Outrequin, Anne Alexandre, Christine Vallet-Coulomb, Clément Piel, Sébastien Devidal, Amaelle Landais, Martine Couapel, Jean-Charles Mazur, Christophe Peugeot, Monique Pierre, Frédéric Prié, Jacques Roy, Corinne Sonzogni, and Claudia Voigt
Clim. Past Discuss.,
Revised manuscript under review for CPShort summary
Continental atmospheric humidity is a key climate parameter poorly captured by global climate models. Model-data comparison approaches applicable beyond the instrumental period are essential to progress on this issue but face a lack of quantitative relative humidity proxies. Here, we calibrate the triple oxygen isotope composition of phytoliths as a new quantitative proxy of continental relative humidity suitable for past climate reconstructions.
Yves Tramblay, Nathalie Rouché, Jean-Emmanuel Paturel, Gil Mahé, Jean-François Boyer, Ernest Amoussou, Ansoumana Bodian, Honoré Dacosta, Hamouda Dakhlaoui, Alain Dezetter, Denis Hughes, Lahoucine Hanich, Christophe Peugeot, Raphael Tshimanga, and Patrick Lachassagne
Earth Syst. Sci. Data, 13, 1547–1560,Short summary
This dataset provides a set of hydrometric indices for about 1500 stations across Africa with daily discharge data. These indices represent mean flow characteristics and extremes (low flows and floods), allowing us to study the long-term evolution of hydrology in Africa and support the modeling efforts that aim at reducing the vulnerability of African countries to hydro-climatic variability.
Basile Hector, Jean-Martial Cohard, Luc Séguis, Sylvie Galle, and Christophe Peugeot
Hydrol. Earth Syst. Sci., 22, 5867–5888,Short summary
The hydrological functioning of western African headwater wetlands remains poorly understood, despite their potential for small-scale farming and their role in streamflow production. We found that land cover changes significantly affect water budgets, and pedo-geological features control dry season baseflow. These are the results of virtual experiments with a physically based critical zone model evaluated against streamflow, evapotranspiration, soil moisture, water table and water storage data.
Delphine J. Leroux, Thierry Pellarin, Théo Vischel, Jean-Martial Cohard, Tania Gascon, François Gibon, Arnaud Mialon, Sylvie Galle, Christophe Peugeot, and Luc Seguis
Hydrol. Earth Syst. Sci., 20, 2827–2840,Short summary
Water is one of the most valuable resources and has an undeniable influence on every aspect of life. Being a very good indicator of the water cycle, the soil water content can be monitored by satellites from space. The region studied here is located in Benin, West Africa, where people have to face major water-related risks every year during the monsoon season. By adjusting the model simulations with satellite observations, river discharge and water table levels have greatly been improved.
E. T. N'Datchoh, A. Konaré, A. Diedhiou, A. Diawara, E. Quansah, and P. Assamoi
Earth Syst. Dynam., 6, 161–174,
F. Lohou, L. Kergoat, F. Guichard, A. Boone, B. Cappelaere, J.-M. Cohard, J. Demarty, S. Galle, M. Grippa, C. Peugeot, D. Ramier, C. M. Taylor, and F. Timouk
Atmos. Chem. Phys., 14, 3883–3898,
A. Richard, S. Galle, M. Descloitres, J.-M. Cohard, J.-P. Vandervaere, L. Séguis, and C. Peugeot
Hydrol. Earth Syst. Sci., 17, 5079–5096,
Related subject area
Subject: Hydrometeorology | Techniques and Approaches: Instruments and observation techniquesMicrophysical 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 grasslandEvaluation of INCA precipitation analysis using a very dense rain gauge network in southeast AustriaRivers 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 regionUse of reflected GNSS SNR data to retrieve either soil moisture or vegetation height from a wheat cropWater-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 bucketPolarimetric radar observations during an orographic rain eventDerivation of a new continuous adjustment function for correcting wind-induced loss of solid precipitation: results of a Norwegian field studyEvolving flood patterns in a Mediterranean region (1301–2012) and climatic factors – the case of Catalonia
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.
Esmail Ghaemi, Ulrich Foelsche, Alexander Kann, and Jürgen Fuchsberger
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort 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 southeast 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.
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.
Sibo Zhang, Nicolas Roussel, Karen Boniface, Minh Cuong Ha, Frédéric Frappart, José Darrozes, Frédéric Baup, and Jean-Christophe Calvet
Hydrol. Earth Syst. Sci., 21, 4767–4784,Short summary
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.
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,
M. Frech and J. Steinert
Hydrol. Earth Syst. Sci., 19, 1141–1152,
M. A. Wolff, K. Isaksen, A. Petersen-Øverleir, K. Ødemark, T. Reitan, and R. Brækkan
Hydrol. Earth Syst. Sci., 19, 951–967,Short summary
The article reports on measurements, analysis and results of a Norwegian field study aimed to adjust automatic precipitation measurements for under-catch during windy conditions. An unique data set could be collected, documenting the under-catch of snow at very high wind speeds for the first time. A new continuous adjustment function for precipitation measured by an automated gauge covering all three precipitation types (snow, mixed and rain) was established.
A. Barrera-Escoda and M. C. Llasat
Hydrol. Earth Syst. Sci., 19, 465–483,Short summary
Catastrophic floods (the most severe ones) in Catalonia from 1301 do not show any statistical trend, while extraordinary floods (moderate ones) have increased since 1850 due to a marked increase in developed land and population in small coastal basins. The most significant flood-rich periods occurred with a strong negative NAO phase. Solar activity has some impact on changes in catastrophic floods: flood-rich periods in autumn generally occurred during periods of increased solar activity.
Aluwihare, S. and Watanabe, K.: Measurement of evaporation on bare soil and estimating surface resistance, J. Environ. Eng., 129, 1157–1168, 2003.
Aubinet, M., Grelle, A., Ibrom, A., Rannik, Ü, Moncrieff, J., Foken, T., Kowalski, A. S., Martin, P. H., Berbigier, P., Bernhofer, C., Clement, R., Elbers, J., Granier, A., Grünwald, T., Morgenstern, K., Pilegaard, K., Rebmann, C., Snijders, W., Valentini, R., and Vesala, T.: Estimates of the annual net carbon and water exchange of forests: the EUROFLUX methodology, Adv. Eco. Res., 30, 113–175, 1999.
Bagayoko, F., Yonkeu, S., Elbers, J., and van de Giesen, N.: Energy partitioning over the West African savanna: Multi-year evaporation and surface conductance measurements in Eastern Burkina Faso, J. Hydrol., 334, 545–559, 2007.
Boone, A., Decharme, B., Guichard, F., de Rosnay, P., Balsamo, G., Beljaars, A., Chopin, F., Orgeval, T., Polcher, J., Delire, C., Ducharne, A., Gascoin, S., Grippa, M., Jarlan, L., Kergoat, L., Mougin, E., Gusev, Y., Nasonova, O., Harris, P., Taylor, C., Norgaard, A., Sandholt, I., Ottlé, C., Poccard-Leclercq, I., Saux-Picart, S., and Xue, Y.: The AMMA Land Surface Model Intercomparison Project (ALMIP), B. Am. Meteorol. Soc., 90, 1865–1880, 2009a.
Brümmer, C., Falk, U., Papen, H., Szarzynski, J., Wassmann, R., and Brüggemann, N.: Diurnal, seasonal, and interannual variation in carbon dioxide and energy exchange in shrub savanna in Burkina Faso (West Africa), J. Geophys. Res., 113, G02030, https://doi.org/10.1029/2007JG000583, 2008.
Businger, J. A., Wyngaard, J. C., Izumi, Y., and Bradley, E. F.: Flux-Profile Relationships in the Atmospheric Surface Layer, J. Atmos. Sci., 28, 181–189, 1971.
Caird, M. A., Richards, J. H., and Donovan, L. A.: Nighttime Stomatal Conductance and Transpiration in C3 and C4 Plants, Plant Physiol., 143, 4–10, https://doi.org/10.1104/pp.106.092940, 2007.
Charney, J. G.: Dynamics of deserts and drought in the Sahel, Q. J. Roy. Meteorol. Soc., 101, 193–202, 1975.
Collatz, G. J., Ribas-Carbo, M., and Berry, J. A.: Coupled photosynthesis-stomatal conductance model for leaves of C4 plants, Funct. Plant Biol., 19, 519–538, 1992.
CSAO: Compte rendu du forum du club du sahel et de l'Afrique de l'Ouest, Peuplement, marché et sécurité alimentaire, Ouagadougou, 4–8 décembre 2012, 1–16, available from http://www.oecd.org/fr/csao/publications/FR-Compte%20rendu
Culf, A. D., Foken, T., and Gash, J. H. C.: The energy balance closure problem, in: Vegetation, water, humans and the climate, A new perspective on an interactive system, edited by: Kabat, P. et al., Springer, Berlin, Heidelberg, 159–166, 2004.
De Condappa, D., Galle, S., Dewandel, B., and Haverkamp, R.: Bimodal zone of the soil textural triangle: Common in tropical and subtropical regions, Soil Sci. Soc. Am. J., 72, 33–40, 2008.
Descloitres, M., Séguis, L., Legchenko, A., Wubda, M., Guyot, A., and Cohard, J. M.: The contribution of MRS and resistivity methods to the interpretation of actual evapo–transpiration measurements: a case study in metamorphic context in north Benin, Near Surf. Geophys., 9, 187–200, 2011.
Detto, M., Montaldo, N., Albertson, J. D., Mancini, M. and Katul, G.: Soil moisture and vegetation controls on evapotranspiration in a heterogeneous Mediterranean ecosystem on Sardinia, Italy, Water Resour. Res., 42, W08419, https://doi.org/10.1029/2005WR004693, 2006.
Doukouré, M.: Variabilité des flux turbulents de surface au sein du bassin versant d'Ara au Bénin, Thèse de doctorat, Université de Grenoble, Grenoble, 171 pp., 2011.
Douville, H., Conil, S., Tyteca, S., and Voldoire, A.: Soil moisture memory and West African monsoon predictability: artefact or reality?, Clim. Dynam., 28, 723–742, https://doi.org/10.1007/s00382-006-0207-8, 2006.
Eltahir, E. A.: A soil moisture–rainfall feedback mechanism 1. Theory and observations, Water Resour. Res., 34, 765–776, 1998.
Faure, P. and Volkoff, B.: Some factors affecting regional differentiation of the soils in the Republic of Benin (West Africa), Catena, 32, 281–306, 1998.
Gentine, P., Entekhabi, D., Chehbouni, A., Boulet, G., and Duchemin, B.: Analysis of evaporative fraction diurnal behaviour, Agr. Forest. Meteorol., 143, 13–29, 2007.
Gentine, P., Entekhabi, D., and Polcher, J.: The Diurnal Behavior of Evaporative Fraction in the Soil-Vegetation-Atmospheric Boundary Layer Continuum, J. Hydrometeorol., 12, 1530–1546, 2012.
Guyot, A., Cohard, J.-M., Anquetin, S., Galle, S., and Lloyd, C. R.: Combined analysis of energy and water balances to estimate latent heat flux of a Sudanian small catchment, J. Hydrol., 375, 227–240, 2009.
Guyot, A., Cohard, J.-M., Anquetin, S., and Galle, S.: Long-term observations of turbulent fluxes over heterogeneous vegetation using scintillometry and additional observations: A contribution to AMMA under Sudano–Sahelian climate, Agr. Forest. Meteorol., 154–155, 84–98, 2012.
Horst, T. W. and Weil, Jc.: Footprint estimation for scalar flux measurements in the atmospheric surface layer, Bound.-Lay. Meteorol., 59, 279–296, 1992.
Hsieh, C.-I., Katul, G., and Chi, T.: An approximate analytical model for footprint estimation of scalar fluxes in thermally stratified atmospheric flows, Adv. Water Res., 23, 765–772, 2000.
Hsieh, C.-I., Katul, G. G., Schieldge, J., Sigmon, J. T., and Knoerr, K. K.: The Lagrangian Stochastic Model for fetch and latent heat flux estimation above uniform and nouniform terrain, Water Resour. Res., 33, 427–438, 1997.
Inagaki, A., Letzel, M. O., Raasch, S., and Kanda, M.: Impact of surface heterogeneity on energy balance: A study using LES, J. Meteorol. Soc. Jpn., 84, 187–198, 2006.
Jarvis, P. G. and McNaughton, K. G.: Stomatal control of transpiration: scaling up from leaf to region, Adv. Eco. Res., 15, 1–49, 1986.
Judex, M., Thamm, H.-P., Röhrig, J., and Schulz, O.: IMPETUS Atlas du Bénin Résultats de recherche 2000–2007, Département de Géographie, Université de Bonn, Allemagne, 2009.
Kabat, P., Dolman, A. J., and Elbers, J. A.: Evaporation, sensible heat and canopy conductance of fallow savannah and patterned woodland in the Sahel, J. Hydrol., 188, 494–515, 1997.
Kaimal, J. C. and Finnigan, J. J.: Atmospheric boundary layer flows: their structure and measurement, Oxford University Press., 1994.
Kanda, M., Inagaki, A., Letzel, M. O., Raasch, S., and Watanabe, T.: LES study of the energy imbalance problem with eddy covariance fluxes, Bound.-Lay. Meteorol., 110, 381–404, 2004.
Kljun, N., Calanca, P., Rotach, M. W., and Schmid, H. P.: A Simple Parameterisation for Flux Footprint Predictions, Bound.-Lay. Meteorol., 112, 503–523, 2004.
Koster, R. D., Dirmeyer, P. A., Guo, Z., Bonan, G., Chan, E., Cox, P., Gordon, C. T., Kanae, S., Kowalczyk, E., Lawrence, D., Liu, P., Lu, C.-H., Malyshev, S., McAvaney, B., Mitchell, K., Mocko, D., Oki, T., Oleson, K., Pitman, A., Sud, Y. C., Taylor, C. M., Verseghy, D., Vasic, R., Xue, Y., and Yamada, T. (The GLACE Team): Regions of Strong Coupling Between Soil Moisture and Precipitation, Science, 305, 1138–1140, 2004.
Kounouhéwa, B., Mamadou, O., Koto N'gobi, G., and Awanou, C. N.: Dynamics and Diurnal Variations of Surface Radiation Budget over Agricultural Crops Located in Sudanian Climate, Atmos. Clim. Sci., 03, 121–131, https://doi.org/10.4236/acs.2013.31014, 2013.
Lebel, T., Parker, D. J., Flamant, C., Bourlès, B., Marticorena, B., Mougin, E., Peugeot, C., Diedhiou, A., Haywood, J. M., Ngamini, J. B., Polcher, J., Redelsperger, J.-L., and Thorncroft, C. D.: The AMMA field campaigns: multiscale and multidisciplinary observations in the West African region, Q. J. Roy. Meteorol. Soc., 136, 8–33, 2009.
Lee, T. J. and Pielke, R. A.: Estimating the Soil Surface Specific Humidity, J. Appl. Meteorol., 31, 480–484, 1992.
Lelay, M. and Galle, S.: How changing rainfall regimes may affect the water balance: a modelling approach in West Africa, in: Regional Hydrological Impacts of Climatic Change: Hydroclimatic variability, edited by: Franks, S., Wagener, T., Bogh, E., Gupta, H. V., Bastidas, L., Nobre, C., and De Oliveira Galvao, C., AISH Publication 296, 203–210, 2005.
Lohou, F., Sa\"id, F., Lothon, M., Durand, P., and Serça, D.: Impact of Boundary–Layer Processes on Near-Surface Turbulence Within the West African Monsoon, Bound.-Lay. Meteorol., 136, 1–23, 2010.
Lohou, F., Kergoat, L., Guichard, F., Boone, A., Cappelaere, B., Cohard, J.-M., Demarty, J., Galle, S., Grippa, M., Peugeot, C., Ramier, D., Taylor, C. M., and Timouk, F.: Surface response to rain events throughout the West African monsoon, Atmos. Chem. Phys. Discuss., 13, 18581–18620, https://doi.org/10.5194/acpd-13-18581-2013, 2013.
Lothon, M., Sa\"id, F., Lohou, F., and Campistron, B.: Observation of the Diurnal Cycle in the Low Troposphere of West Africa, Mon. Weather Rev., 136, 3477–3500, 2008.
Mauder, M. and Foken, T.: Documentation and instruction manual of the eddy covariance software package TK2, Univ., Abt. Mikrometeorologie Bayreuth, Bayreuth, 2004.
Mauder, M., Jegede, O. O., Okogbue, E. C., Wimmer, F., and Foken, T.: Surface energy balance measurements at a tropical site in West Africa during the transition from dry to wet season, Theor. Appl. Climatol., 89, 171–183, 2007.
Monteny, B. A., Lhomme, J. P., Chehbouni, A., Troufleau, D., Amadou, M., Sicot, M., Verhoef, A., Galle, S., Said, F., and Lloyd, C. R.: The role of the Sahelian biosphere on the water and the CO2 cycle during the HAPEX-Sahel experiment, J. Hydrol., 188–189, 516–535, https://doi.org/10.1016/S0022-1694(96)03191-5, 1997.
Monteny, B. A., Lhomme, J. P., Chehbouni, A., Troufleau, D., Amadou, M., Sicot, M., Verhoef, A., Galle, S., Said, F., and Lloyd, C. R.: The role of the Sahelian biosphere on the water and the CO2 cycle during the HAPEX-Sahel experiment, J. Hydrol., 188–189, 516–535, https://doi.org/10.1016/S0022-1694(96)03191-5, 2007.
Moore, C. J.: Frequency response corrections for eddy correlation systems, Bound.-Lay. Meteorol., 37, 17–35, 1986.
Parker, D. J., Burton, R. R., Diongue-Niang, A., Ellis, R. J., Felton, M., Taylor, C. M., Thorncroft, C. D., Bessemoulin, P., and Tompkins, A. M.: The diurnal cycle of the West African monsoon circulation, Q. J. Roy. Meteorol. Soc., 131, 2839–2860, 2005.
Philippon, N. and Fontaine, B.: The relationship between the Sahelian and previous 2nd Guinean rainy seasons: a monsoon regulation by soil wetness?, Ann. Geophys., 20, 575–582, https://doi.org/10.5194/angeo-20-575-2002, 2002.
Pospichal, B., Karam, D., Crewell, S., Flamant, C., Hünerbein, A., Bock, O., and Sa\"id, F.: Diurnal cycle of the intertropical discontinuity over West Africa analysed by remote sensing and mesoscale modelling, Q. J. Roy. Meteorol. Soc., 136, 92–106, 2010.
Ramier, D., Boulain, N., Cappelaere, B., Timouk, F., Rabanit, M., Lloyd, C. R., Boubkraoui, S., Métayer, F., Descroix, L., and Wawrzyniak, V.: Towards an understanding of coupled physical and biological processes in the cultivated Sahel – 1. Energy and water, J. Hydrol., 375, 204–216, 2009.
Redelsperger, J.-L., Thorncroft, C. D., Diedhiou, A., Lebel, T., Parker, D. J., and Polcher, J.: African Monsoon Multidisciplinary Analysis: An International Research Project and Field Campaign, B. Am. Meteorol. Soc., 87, 1739–1746, https://doi.org/10.1175/BAMS-87-12-1739, 2006.
Richard, A., Galle, S., Descloitres, M., Cohard, J.-M., Vandervaere, J.-P., Séguis, L., and Peugeot, C.: Interplay of riparian forest and groundwater in the hillslope hydrology of Sudanian West Africa (northern Benin), Hydrol. Earth Syst. Sci., 17, 5079–5096, https://doi.org/10.5194/hess-17-5079-2013, 2013.
Sakaguchi, K. and Zeng, X.: Effects of soil wetness, plant litter, and under-canopy atmospheric stability on ground evaporation in the Community Land Model (CLM3.5), J. Geophys. Res., 114, D01107, https://doi.org/10.1029/2008JD010834, 2009.
Santanello, J. A. and Friedl, M. A.: Diurnal Covariation in Soil Heat Flux and Net Radiation, J. Appl. Meteorol., 42, 851–862, 2003.
Schmid, H. P.: Footprint modeling for vegetation atmosphere exchange studies: a review and perspective, Agric. Forest. Meteorol., 113, 159–183, 2002.
Schotanus, P., Nieuwstadt, F. T. M., and De Bruin, H. A. R.: Temperature measurement with a sonic anemometer and its application to heat and moisture fluxes, Bound.-Lay. Meteorol., 26, 81–93, 1983.
Schüttemeyer, D., Moene, A. F., Holtslag, A. A. M., Bruin, H. A. R., and van Giesen, N.: Surface Fluxes and Characteristics of Drying Semi-Arid Terrain in West Africa, Bound.-Lay. Meteorol., 118, 583–612, 2006.
Seghieri, J., Vescovo, A., Padel, K., Soubie, R., Arjounin, M., Boulain, N., de Rosnay, P., Galle, S., Gosset, M., Mouctar, A. H., Peugeot, C., and Timouk, F.: Relationships between climate, soil moisture and phenology of the woody cover in two sites located along the West African latitudinal gradient, J. Hydrol., 375, 78–89, 2009.
Séguis, L., Kamagaté, B., Favreau, G., Descloitres, M., Seidel, J.-L., Galle, S., Peugeot, C., Gosset, M., Le Barbé, L., Malinur, F., Van Exter, S., Arjounin, M., Boubkraoui, S., and Wubda, M.: Origins of streamflow in a crystalline basement catchment in a sub-humid Sudanian zone: The Donga basin (Benin, West Africa): Inter-annual variability of water budget, J. Hydrol., 402, 1–13, 2011.
Sellers, P. J., Heiser, M. D., and Hall, F. G.: Relations between surface conductance and spectral vegetation indices at intermediate (100 m2 to 15 km2) length scales, J. Geophys. Res., 97, 19033–19059, 1992.
Snyder, K. A., Richards, J. H., and Donovan, L. A.: Night-time conductance in C3 and C4 species: do plants lose water at night?, J. Exp. Bot., 54, 861–865, https://doi.org/10.1093/jxb/erg082, 2003.
Steinfeld, G., Letzel, M. O., Raasch, S., Kanda, M., and Inagaki, A.: Spatial representativeness of single tower measurements and the imbalance problem with eddy-covariance fluxes: Results of a large-eddy simulation study, Bound.-Lay. Meteorol., 123, 77–98, 2007.
Sultan, B. and Janicot, S.: The West African monsoon dynamics, Part II: The "preonset" and "onset" of the summer monsoon, J. Climate, 16, 3407–3427, 2003.
Taylor, C. M. and Lebel, T.: Observational evidence of persistent convective-scale rainfall patterns, Mon. Weather Rev., 126, 1597–1607, 1998.
Taylor, C. M., de Jeu, R. A. M., Guichard, F., Harris, P. P., and Dorigo, W. A.: Afternoon rain more likely over drier soils, Nature, 489, 423–426, 2012.
Thornton, E.: Technical Description of version 4.0 of the Community Land Model (CLM), available from: http://nldr.library.ucar.edu/repository/assets/technotes/asset-000-000-000-847.pdf (last access: 29 May 2013), 2010.
Timouk, F., Kergoat, L., Mougin, E., Lloyd, C. R., Ceschia, E., Cohard, J. M., Rosnay, P., Hiernaux, P., Demarez, V., and Taylor, C. M.: Response of surface energy balance to water regime and vegetation development in a Sahelian landscape, J. Hydrol., 375, 178–189, 2009.
UN – United Nations, Department of Economic and Social Affairs, Population Division, World Population Prospects: The 2010 Revision, Press Release (3 May 2011): World Population to reach 10 billion by 2100 if fertility in all countries converges to replacement Level, available on: http://esa.un.org/unpd/wpp/other-information/press_release wpp2010.pdf (last access: 19 June 2013), 2011.
van de Griend, A. A. and Owe, M.: Bare soil surface resistance to evaporation by vapor diffusion under semiarid conditions, Water Resour. Res., 30, 181–188, 1994.
Webb, E. K., Pearman, G. I., and Leuning, R.: Correction of flux measurements for density effects due to heat and water vapour transfer, Q. J. Roy. Meteorol. Soc., 106, 85–100, 1980.
Weiss, M., Baret, F., Smith, G. J., Jonckheere, I., and Coppin, P.: Review of methods for in situ leaf area index (LAI) determination: Part II, Estimation of LAI, errors and sampling, Agr. For. Meteorol., 121, 37–53, 2004.
Wilson, K., Goldstein, A., Falge, E., Aubinet, M., Baldocchi, D., Berbigier, P., Bernhofer, C., Ceulemans, R., Dolman, H., Field, C., Grelle, A., Ibrom, A., Law, B. E., Kowalski, A., Meyers, T., Moncrieff, J., Monson, R., Oechel, W., Tenhunen, J., Valentini, R., and Verma, S. : Energy balance closure at FLUXNET sites, Agr. Forest. Meteorol., 113, 223–243, 2002.
Xue, Y. and Shukla, J.: The influence of land surface properties on Sahel climate, Part I: Desertification, J. Climate, 6, 2232–2245, 1993.
Zeng, N., Neelin, J. D., Lau, K.-M., and Tucker, C. J.: Enhancement of Interdecadal Climate Variability in the Sahel by Vegetation Interaction, Science, 286, 1537–1540, 1999.