Extended Data Fig. 4: Variation in dust concentration and rainfall over the Bodélé Depression are strong predictors of variation in PM2.5 concentrations in other parts of Africa.
From: Dust pollution from the Sahara and African infant mortality
Figure shows estimation results for six different specifications of the first stage (Eq. (1)) relationship between the conditions in the Bodélé instrument and local PM2.5. Models 1 and 4 include DHS cluster, birth year, and country by month fixed effects with household and local weather controls and the dust (Model 1) or rainfall (Model 4) instrument. Models 2 and 5 add additional controls for ENSO conditions and Models 3 and 6 replace DHS cluster fixed effects with a mother fixed effect to restrict comparisons to siblings. The different specifications consistently find dust in the Bodélé Depression is positively associated and rainfall negatively associated with PM2.5 concentrations in both our West African sample (white dots) and full African sample (black dots; see Extended Data Fig. 1 for study locations). Contemporaneous effects are large, statistically significant (F-stats of 17-366), and similar to the main specification without lags (Fig. 2) while lagged effects are small and not statistically significant. A complete description of the fixed effects (dummy variables) and controls is included in the Methods section.
