Note: Intro -- Contents -- 1 Foreword: International Space Science Institute (ISSI) Workshop on Remote Sensing and Water Resources -- References -- 2 Modelling Freshwater Resources at the Global Scale: Challenges and Prospects -- Abstract -- 1 Introduction -- 2 Approaches for Modelling Global Hydrology -- 3 Challenges -- 3.1 Modelling Human Water Use -- 3.2 Uncertain Climate Input -- 3.2.1 Uncertainties in Historic Climate Information and Their Impact on Simulating Water Resources -- 3.2.2 Uncertainties in Global and Regional Climate Projections and Their Impact on Simulating Future Water Resources -- 3.3 Quantification of the Role of Active Vegetation Under Changing Climate and CO2 Concentrations -- 3.4 Understanding of Why GHMs (Including Global Irrigation Models) Respond Differently to Changed Climate Input -- 3.5 Modelling of Monthly Time Series of River Discharge and Human Water Use to Support More Meaningful Indicators of Water Stress for Both Humans and Ecosystems -- 3.6 Simulation of Groundwater-Surface Water Interaction and Capillary Rise by Gradient-Based Groundwater Modelling -- 3.7 Detection and Attribution of Observed Changes in Freshwater Systems -- 4 Prospects -- 4.1 Multi-criteria Validation Against River Discharge and Geodetic/Remote Sensing Observations -- 4.2 Multi-criteria Calibration and Data Assimilation -- 4.3 Hyperresolution Global Hydrological Modelling -- 5 Conclusions -- Acknowledgments -- References -- 3 On the Use of Hydrological Models and Satellite Data to Study the Water Budget of River Basins Affected by Human Activities: Examples from the Garonne Basin of France -- Abstract -- 1 Introduction -- 2 The Water Balance at the Scale of the Entire Garonne Basin -- 2.1 Climate and Physical Properties -- 2.2 Anthropization, Environmental Change due to Human Actions. , 2.3 Hydrological Regime of the Garonne Basin: Trends and Variability -- 3 Interest of Fine Scale Data to Validate or Constrain Models -- 3.1 Snow Cover -- 3.2 Crop Sowing Date -- 4 Explicit Modeling of Human Activities at the Scale of the Basin Using a Multi-agent Simulation Platform -- 4.1 MAELIA: A Multi-agent Platform of Social-Ecological Systems -- 4.1.1 Agricultural Processes -- 4.1.2 Hydrological Processes -- 4.1.3 Water Management -- 4.1.4 Other Socioeconomic Processes -- 4.1.5 Calibration of the Model -- 4.2 Evaluation and Impact of Changes in the Spatial Allocation of Cropping Systems in the Aveyron Sub-basin -- 4.2.1 Studied Area and Methodology -- 4.2.2 Evaluation of the MAELIA Instance -- 4.2.3 Impact Assessment of Crop Rotation Changes -- 5 Conclusions -- Acknowledgments -- References -- 4 On Creating Global Gridded Terrestrial Water Budget Estimates from Satellite Remote Sensing -- Abstract -- 1 Introduction -- 2 Data and Methodology -- 2.1 Utilized Data -- 2.2 Product Merging and Water Budget Closure -- 2.3 Design of the Budget Closure Experiments -- 3 Results and Discussion -- 3.1 Roles of Non-satellite Sources in Closing the Water Budget -- 3.2 Roles of In Situ Precipitation Observations in Water Budget Closure -- 3.3 Effects of Different Remote Sensing ET Products in the Water Budget Closure -- 3.4 Roles of CKF in Constraining the Water Balance -- 3.5 Runoff Validation Against GRDC Data at the Basin Scale -- 4 Conclusions -- Acknowledgments -- References -- 5 Lake Volume Monitoring from Space -- Abstract -- 1 Introduction -- 2 Satellite Altimetry -- 2.1 Introduction -- 2.2 Basics of Satellite Altimetry -- 2.3 Past, Present, and Future Satellite Altimetry -- 2.4 Combination of Multi-Satellite Data -- 2.5 Accuracy of Satellite Altimetry Over Lakes -- 3 Satellite Imagery -- 4 Storage Change Calculation. , 5 Case Study: The Tibetan Plateau -- 6 Results -- 7 Conclusions -- Acknowledgments -- References -- 6 The SWOT Mission and Its Capabilities for Land Hydrology -- Abstract -- 1 SWOT Mission Overview -- 1.1 The Needs for a Global Water Surface Mission and Its Requirements -- 1.2 Characteristics of the KaRIn Instrument -- 1.3 SWOT Measurements over Terrestrial Surface Waters -- 1.4 SWOT Spatiotemporal Coverage -- 2 River Studies -- 2.1 Rivers Seen by SWOT -- 2.2 Instantaneous Direct River Discharge Estimations -- 2.3 Data Assimilation and Optimal Interpolation -- 3 Lake/Reservoir Studies and Other Land Hydrology Applications -- 3.1 Lakes and Reservoirs -- 3.2 Other Land Hydrology Applications and Synergistic Land Sciences -- 4 Conclusions and Perspectives -- Acknowledgments -- References -- 7 Toward a High-Resolution Monitoring of Continental Surface Water Extent and Dynamics, at Global Scale: from GIEMS (Global Inundation Extent from Multi-Satellites) to SWOT (Surface Water Ocean Topography) -- Abstract -- 1 Introduction -- 2 The Potential and Limitation of Satellite Techniques for Surface Water Estimation -- 2.1 Visible (VIS) and Near-Infrared (NIR) Observations -- 2.2 Active Microwave Observations -- 2.3 Passive Microwave Observations -- 3 A Multi-satellite Methodology for Global Surface Water Estimation -- 3.1 The Global Inundation Extent from Multi-satellites (GIEMS) -- 3.2 Downscaling of GIEMS -- 3.2.1 Downscaling Based on High-Resolution Satellite Observations -- 3.2.2 Downscaling Based on Topography Information -- 4 The Future with SWOT -- 5 Conclusions and Perspective -- Acknowledgments -- References -- 8 Assessing Global Water Storage Variability from GRACE: Trends, Seasonal Cycle, Subseasonal Anomalies and Extremes -- Abstract -- 1 Introduction -- 2 Data -- 2.1 GRACE Data -- 2.2 Filtered Grids of Atmospheric Reanalysis -- 3 Methods. , 3.1 Signal Decomposition -- 3.1.1 Background and Previous Approaches -- 3.1.2 Seasonal Trend Decomposition Using Loess (STL) -- 3.2 Monthly Averaging of the Daily Decomposed Forcing Time Series -- 3.2.1 Limitations of the Arithmetic Mean for the Comparison of High-Frequency Anomalies -- 3.2.2. Comparing Flux and State Variables at Different Temporal Resolutions -- 3.2.3 Weights Based on Integrated Exponential Decay Functions -- 3.2.4 Shape and Properties of the Weighting Function -- 3.3 Significance Testing and Correlation Analysis -- 3.3.1 Linear Trends -- 3.3.2 Inter-Annual Anomalies -- 3.3.3 Seasonal Cycle -- 3.3.4 Subseasonal Residuals -- 3.4 Identifying Droughts in the GRACE Record -- 4 Global Hydrological Variability in the GRACE Data -- 4.1 Distribution of GRACE Variance Among Temporal Components -- 4.2 Linear Trends -- 4.3 Inter-Annual Anomalies -- 4.4 Seasonal Cycle -- 4.5 Subseasonal Residuals -- 4.6 Droughts -- 5 Conclusions -- Acknowledgments -- Appendix 1: STL for Unevenly Spaced Time Series -- Locally Weighted Regression (Loess) -- Inner Loop -- Outer Loop -- Choosing the Parameters -- Appendix 2 -- Analytical Integration of the Weighting Function -- References -- 9 Groundwater Storage Changes: Present Status from GRACE Observations -- Abstract -- 1 Introduction -- 2 Groundwater Depletion from GRACE -- 2.1 Groundwater Depletion in North West India -- 2.2 Groundwater Depletion in the California Central Valley -- 2.3 Groundwater Depletion in Southern Murray-Darling Basin -- 2.4 Groundwater Depletions in Other Regions -- 3 Major Challenges in Monitoring Groundwater Change Using GRACE -- 3.1 Uncertainty of SSS Water Storage Changes -- 3.2 Uncertainties in GRACE TWS Storage Changes -- 4 Summary -- Acknowledgments -- References -- 10 Modeling Groundwater Depletion at Regional and Global Scales: Present State and Future Prospects -- Abstract. , 1 Introduction -- 2 Human Water Use and Groundwater Pumping -- 3 Global and Regional Assessments of Groundwater Depletion -- 4 Groundwater Depletion and Sea-Level Rise -- 5 Future Projections of Groundwater Depletion -- 6 A Way Forward -- 6.1 Quantifying the Sustainable Yield with Use of Satellite Observations and Integrated Modeling Framework -- 6.2 Assessing Food Security -- 6.3 Assessing Regional Mitigation Strategies on Food Security -- Acknowledgments -- References -- 11 What Can be Expected from the GRACE-FO Laser Ranging Interferometer for Earth Science Applications? -- Abstract -- 1 Introduction -- 2 Simulation Assumptions and Strategy -- 3 Results in the Spectral and Spatial Domain -- 4 Regional Applications Using Simulated MWI and LRI Data -- 5 Error Analysis -- 6 Summary and Conclusions -- 7 Acknowledgments -- References -- 12 Subsurface Hydrology of the Lake Chad Basin from Convection Modelling and Observations -- Abstract -- 1 Introduction -- 2 Description of the Lake Chad Basin -- 2.1 Hydrology of Lake Chad -- 2.2 Geology of the Chad Basin -- 2.3 Hydrogeology of the Basin -- 2.4 Potential Permeability Field of the Basin -- 3 2D Convective Model -- 4 Discussion -- 4.1 Relations Between the Deep Convective Circulation and Thermal Data -- 4.1.1 Subsurface Thermal Data -- 4.1.2 Surface Thermal Data -- 4.2 Relation Between Deep Convective Circulation and Hydrogeology -- 4.2.1 Evolution of the Water Composition -- 4.2.2 Comparison Between Convective Velocity and Transient Variations of the Piezometric Level: Inference on Water Mass Changes -- 5 Conclusions -- Acknowledgments -- Appendix 1: Governing Equations, Parameters and Equations of State -- Appendix 2: Parameter values -- Appendix 3: Method and Boundary Conditions -- Appendix 4: Evaluation of the Hydrological and Thermal Characteristics of Our Model -- References. , 13 Water and Food in the Twenty-First Century.