Anthropogenic emissions into the atmosphere are central to many of the issues that plague planetary health, and there are great research and communication challenges in assessing their impacts and informing policy. These challenges motivate my research. I am focused on characterizing how anthropogenic emissions contribute to poor air quality and public health, how emissions of carbon dioxide contribute to climate forcing, how crops and forests are damaged by human emission activities, and how these broad components of planetary health can interact with one another.

The air quality and health implications of increasing wildfires in the Amazon

Objective: Assess the health impacts associated with increased PM2.5 exposure in Brazil during the 2019 Amazon fire season.

Summary: GEOS-Chem adjoint senstivities of PM2.5 exposure in Brazil to emissions of primary carbonaceous aerosols were calculated and then combined with biomass burning emissions from FINN and QFED. Overall, we estimated that nearly 5000 premature deaths in Brazil in 2019 were associated with fires between July and September and that the 2019 fire season led to more air quality impacts than 2018.

Using remote-sensing data to characterize the sources of urban air quality; a case study in Washington, D.C.

Objective: Develop a source apportionment framework of air quality health impacts at the urban-scale by leveraging adjoint modeling and remote-sensing observations.

Summary: Using the city of Washington, D.C. as a test-bed we characterize species-specific, regional and sectoral contributions of emissions to air quality and health. We identified the sectors and regions that had the greaetst impact on air quality in Washington DC.

Characterizing the sources of country-scale air quality health impacts in G20 countries

Objective: Identify the sectoral and country-scale contributions to air pollution-related premature deaths in G20 countries and assess how changes in emissions could lead to public health benefits.

Summary: The Group of Twenty (G20) countries are a collection of the world's largest and most influential economies and are uniquely poised to take action to reduce the global health burden associated with air pollution. We identified the leading contributors to air pollution in the G20 countries and estimated that hundreds of thousands of premature deaths could be avoided from mitigation efforts targeting transportation and power generation emissions.

Assessing the health benefits of radially applied transportation policies in 14 US cities

Objective: Identify the greatest contributors to air pollution the 14 US C40 cities and characterize the accrued benefits of larger and larger regions adopting a mitigation policy.

Summary: For the 70.2 million people living in these cities, we estimate that 27740 PM2.5- and O3-related premature deaths and 126600 NO2-related new asthma cases were attributable to air pollution exposure in 2011. The findings suggest that the proportion of urban air pollution that is regional is greater for premature deaths than new asthma cases and for the eastern US than the western US.

Nawaz et al. To be submitted March 2023

Assessing source contributions of air pollution in Santiago and estimating climate co-benefits in a new nested domain

Objective: Develop a new nested domain for GEOS-Chem and its adjoint for the purpose of source apportionment and mitigation scenario impact assessment in Santiago, Chile.

Status: Ongoing.