Projected primary anthropogenic mercury emissions in 2050 (panel a) and resulting changes in atmospheric deposition relative to 2015 (panel b). Year 2050 mercury emissions scenarios are from Streets et al.  based on IPCC projections and adjusted biomass burning for consistency with Streets et al. . These scenarios are bounded by AIB representing a “business-as-usual” scenario with rapid economic growth, while B2 represents a best-case scenario without mercury specific controls (environmental sustainability initiatives and widespread implementation of control technology). The legacy component of deposition is driven by reemissions of previously deposited anthropogenic mercury from oceanic and terrestrial ecosystems. Panel (b) is based on the modeling analysis of Amos et al. .