LIST OF TABLES AND FIGURES Figure 1: Available discharge data for all stations from different sources ................................................... 9 Figure 2: Available data for in situ discharge from various sources (blue) and merged water surface elevation from altimeter (green) from each station. The period where the two data sets overlap is represented in red with the number of overlap’s days. ..................................................................... 10 Figure 3: Rating curve computation methodology ....................................................................................... 13 Figure 4:
Rating curve for the Near-Brookings station (Mississippi basin) before (left) and after (right) Figure 5: Flowchart of the stochastic quantile mapping function algorithm (adapted from Elmi et at., excluding data points associated with temperature variations (below 0°C). .................................. 17 2021, and Saemian et al., 2024) ....................................................................................................... 22 Figure 6: Weights of the daily data of each sensor according to the temporal distance by the nearest sensing day. The weights are distributed with a gaussian function River. ....................................... 27 Table 1:
Summary of the calibration and validation periods for each station, along with the number of days available for both calibration and validation. Stations marked with an asterisk (*) indicate cases where there is too little overlap between discharge and water surface elevation data to separate into calibration and validation periods. In these instances, all available data will be used for calibration or another method to derive discharge from altimetry will be use. .......................... 11 Table 2: Description of the datasets for multispectral images.
It includes selected product, reflectance type, platform used to analyze the data (GEE is Google Earth Engine, SH is Sentinel-HUB, EC is Earth Console), period of data availability, spatial resolution and revisit time. ............................... 25 REFERENCE DOCUMENTS [RD-1] D.2. Selection of river basins. CCI River Discharge precursor project Document (CCI-Discharge- 0004-RP_WP2, Issue 1.0) [RD-2] D.3.1. Water Surface Elevation (WSE) Algorithm Theoretical Basis Document (ATBD) (CCI- Discharge-0005-ATBD-WSE, Issue 2.0) [RD-3] he ESA river discharge CCI project - https://climate.esa.int/en/projects/river-discharge/about-the- river-discharge-project/ D.3 River Discharge ATBD. Reference:
RD_CCI-0006-ATBD - Issue 2.0 – 31/07/2025 Open/Public © 2019 CLS. All rights reserved. Proprietary and Confidential. 5/31