Dataset (Version 1) associated with manuscript: High-resolution numerical assessment of large-scale riverine alkalinity modification scenarios along the southern coast of the United States

This dataset is organized as follows: 1. **Validation** Includes both model outputs and observational datasets used to validate and calibrate model performance (Appendix A). Specifically, these datasets were used to evaluate SST, SSS, surface pCO₂, surface chlorophyll concentration, NPP, TALK, and DIC. 2. **Monthly Averaged Model Output** Includes monthly averaged fields of air–sea CO₂ flux, passive tracer concentrations, mixed layer depth, TALK, and DIC. These datasets were used to reproduce Figures 2, 3, S4, and S12. 3. **Processed Model Output for Budget Analysis** Includes processed model output in MATLAB (*.mat*) format. The dataset contains 27 variables integrated over the surface mixed layer (SML) or the full water column, provided at daily temporal resolution and on a grid-by-grid basis. These data were used for budget analyses, η calculations, and other diagnostic analyses presented in Figures 4–7 and Figures S2, S5, and S10–S11. Detailed descriptions of all variables are provided in *Fcalculation.docx*. 4. **Scripts for Conceptual Diagrams** Includes the scripts used to generate the conceptual diagrams shown in Figure 8 and Figure S3. 5. **Omega Analysis Data** Includes the processed datasets used for the Omega analysis presented in Figures S6 and S7. 6. CROCO grid information Experiments names Baseline: Control run Case 3 and 4: 2017 Year10% (AE and EW) Case 5 and 6: Jan 100% (AE and EW) Case 7 and 8: Jan 10% (AE and EW) Case 9 and 10: May Equilibrium Jan 10% (AE and EW)