Diverging Trends — Population & Declining River Discharge, 1980

Map view

Discharge trend class Share of declining cells Decline × population growth Population change

country names

Exposed population over time ?

The primary definition weights each basin's population by its share of declining discharge cells (no arbitrary threshold). All three definitions roughly double over 40 years.

Why did exposure grow? ?

Region:

The global concentration effect, resolved ?

Positive bars push exposure up. The “between regions” bar means: regions that are already more exposed than average (South Asia, Sub-Saharan Africa, MENA) grew fastest. The small negative “within regions” bar means people did not, on net, move toward declining basins inside their region.

Mini-glossary

River discharge: The volume of water flowing through a river (m³/s). Here: monthly values on a global 0.5° grid, 1979–2019, reconstructed by the GLORIF1 dataset.
Declining / increasing: A statistically significant downward/upward trend of annual mean discharge over 1980–2019 (Mann–Kendall test with false-discovery-rate control — a standard guard against false positives when testing 62,464 cells at once).
Share of declining cells: The fraction of a basin's discharge grid cells that are “declining”. 0% = none, 100% = all. The primary exposure measure weights population by this share.
Compound hotspot: A basin that is in the top third worldwide for both discharge decline and population growth, and whose neighbors are too (tested with local join count statistics; only statistically significant cluster members are outlined).
LMDI decomposition: An accounting method (from energy economics) that splits a change into named contributions that add up exactly — no unexplained remainder.

Data & provenance

Every number shown is machine-generated by the analysis pipeline (configuration hash ). Data: GLORIF1 discharge reconstruction (CC-BY 4.0), GHS-POP R2023A population (CC-BY 4.0), HydroBASINS v1.c (HydroSHEDS license), Natural Earth country borders (public domain), G-RUN ENSEMBLE runoff (CC-BY 4.0, robustness check). Map geometries are simplified for display; all statistics were computed on full-resolution data.

This dashboard is a research companion, not an operational water-risk product. Basin values are statistical aggregates of a coarse (0.5°) reconstruction and must not be used for local planning decisions.

Diverging Trends: Population Dynamics in Basins with Declining River Discharge

What am I looking at?

How to read the map

Three honest caveats (please read)