Atmospheric Chemistry Program Seminar

International air quality, health, and climate impacts of cookstoves, diesel NOx, and other anthropogenic sectors via PM2.5 and O3 by Daven Henze, CU-Boulder Mech. Eng.

"Diesel cars, trucks, and buses produce ~70% of global land transportation emissions of nitrogen oxides (NOx), a key PM2.5 and ozone precursor. Globally over 3 billion people presently use solid fuel for meal preparation. What are the impacts of these activities on the environmental through atmospheric chemistry and transport? Which species dominates the local and long-range health impacts of air pollution? I will first discuss the use of models and remote sensing measurements to evaluate the domestic and international contributions to PM2.5 and O3, and their impacts on human health and climate. Source-receptor relationships are developed using adjoint sensitivity analysis, constraints from remote sensing observations, and parameterized climate model sensitivities. This talk will then delve into application of these relationships to estimate impacts of diesel NOx emissions standards and solid fuel use in major markets and source regions worldwide. We find that the per-cookstove impacts on ambient air quality and global temperature changes are pronounced in several countries not typically targeted in cookstove mitigation efforts (e.g., Ukraine and Romania). We also show that real-world diesel NOx emissions in 11 markets representing ~80% of global diesel vehicle sales are significantly higher than certification limits indicate. This excess NOx contributed an estimated ~39,000 additional ozone- and PM2.5-related premature deaths globally in 2015, with a larger portion of this owing to excessive emissions from heavy duty vehicles than from defeat devices on light duty vehicles. Lastly, we present recent evaluation of the premature deaths and preterm births associated with global O3 exposure, showing that the former is possibly several times larger than previously expected, rivaling the health impacts of PM2.5 in severity."