volta-drought-propagation: code and derived data for sparse-gauge tests of drought propagation in the Volta Basin
Year: 2026
Type: software
Abstract: Code and derived data for the article Regime shift, rising runoff efficiency and sparse gauging: limits to testing drought propagation in a Sahel–savanna landscape (I. Quist, M. Evi, A.B. Owusu and B.N.Y. Quist). The study covers the Volta Basin above Akosombo (18 GRDC gauges, 1961–2007; GPCC rainfall, 1951–2020; 16 CMIP6 models). The scripts (i) test for change points and trends in rainfall, drought synchrony and runoff at fixed rainfall; (ii) relate basin drought to six climate indices with wavelet coherence, seasonal correlations and event-rate models; (iii) match daily SSI drought events between linked gauges with observation-conditioned measures, an availability-aware permutation null, equivalence tests against the Ebro Basin, identifiability and synthetic-truth experiments and a 129-node GEOGLOWS v2 reanalysis network; and (iv) drive a leakage-free hybrid wavelet–machine learning transfer model with bias-adjusted CMIP6 output to project drought risk and the monitoring horizon needed to test propagation. reproduce.sh regenerates every derived table and figure from the raw inputs; verify_manuscript_numbers.py checks the reported numbers against the shipped tables; a continuous-integration workflow re-runs the checksum, number and test checks on every change; MANIFEST.md maps each table and figure of the article and its Supplementary Material to its source file and script. GRDC daily discharge is not redistributed (see DATA.md); all other inputs are open and are downloaded by the scripts. Code: MIT licence. Derived data, tables and figures: CC BY 4.0 (LICENSE-DATA).
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7224745245