16.6.2 Hydroclimate and the Harappan transformation

16.6.2 Hydroclimate and the Harappan transformation

The Indus study combines paleoclimate archives, transient climate simulations, and hydrological reconstruction. It argues that persistent drought likely reduced freshwater availability and may have contributed to population dispersal, while explicitly retaining climatic, social, and economic alternatives [ Solanki et al. , 2025 ] .

The local harness applies D3-style forcing to VIC: precipitation is scaled by \(0.87\) and temperature is increased by \(0.5^\circ \)C. Restoring both changes raises the sixteen-cell sample’s water-availability proxy from \(27.924\) to \(31.601\) mm, or \(13.17\% \). The source paper’s Figure 4 data independently contain a mean D3 discharge anomaly of \(-8.49\% \) across eighteen stations.

The repository does not contain the authors’ exact Indus transient-climate forcing grids. This comparison supports the transparent counterfactual adapter’s direction of response, but is not a reproduction of the published basin maps or a causal demonstration of societal collapse.

Experiment: Prometheus substrate: Indus hydrology. Executable edit: compare a 13% precipitation deficit plus \(0.5^\circ \)C warming with restored forcing in VIC.
Result: the sample-basin water-availability proxy increases by 3.677 mm, or 13.17%.
Admitted: execution and provenance of the local hydrological counterfactual.
Not admitted: reproduction of the paper’s basin maps or a single-cause theory of Harappan transformation.