PM25_shock_ssp1
This layer measures the projected change in fine particulate matter (PM2.5) air pollution between today and mid-century under a sustainable-development future.
Category: Scenario Coverage: Global Format: Raster grid (~100 km) Used in risk analysis: No (contextual layer; not used in materiality scoring)
What it shows
This layer measures the projected change in fine particulate matter (PM2.5) air pollution between today and mid-century under a sustainable-development future. Rather than showing the absolute level of pollution, it highlights where air quality is expected to deteriorate or improve the most, so users can see where future change — not just present conditions — drives air-pollution risk.
How it is built
The shock is derived from CMIP6 climate-model projections under SSP1-2.6, an optimistic low-emissions pathway. For each location it compares projected 2050 PM2.5 against a 2014 baseline and expresses the difference as a relative change. The change is then dampened in already very clean areas: where baseline concentrations sit below a health-relevant "very low" threshold, the signal is attenuated so that ultra-clean regions such as the Arctic and open ocean do not show misleadingly large percentage shocks. The result is a coarse global grid (roughly 100 km cells).
How to read it
Higher positive values mean a larger projected worsening of fine-particulate pollution by 2050; values near zero mean little expected change; negative values indicate projected improvement. Because clean baseline regions are deliberately down-weighted, the most prominent signals appear in already-populated or already-polluted areas.
Source
CMIP6 climate models (WGCM CMIP6 ensemble), models GFDL-ESM4, GISS-E2-1-G and MIROC-ES2L, scenario SSP1-2.6; 2014 baseline versus 2050 projection.
Comparison with the WWF Risk Filter Suite
The WWF Risk Filter Suite publishes present-day risk indicators, not forward-looking scenario shocks. This layer is a temporal change-variant of an air-quality risk WWF only assesses for current conditions, so it has no distinct WWF equivalent and is a Darwin scenario extension.
Legend
Symbolised field: PM2.5 purity shock (%)
Generated from darwin/layers/layer-pm25-shock-ssp1.toml and risk_indicator_pairs.toml (develop).