Atmosphere

The chemistry of the gases and particles in the air around is hugely important. Understanding of atmospheric chemistry enables new pathways to reduce air pollution and climate change.

To study this topic requires an approach that combines fundamental laboratory studies on the physico-chemical properties of atmospheric constituents with observations of the abundance and variability of these moities and numerical model simulations that integrate our understanding of the sources and fate of these compounds and with which we can test hypothesis on how they will change under different conditions.

Selected Publication

A critical review of changes in the tropospheric ozone burden and budget from 1850 to 2100
In this critical review, we assess our evolving understanding of the physical and chemical processes that control the burden and budget of tropospheric ozone. Analysis of 1850 to 2010 data indicates that there has been significant growth in the ozone burden from 1850 to 2000 but smaller growth between 1960 and 2000 and that the models simulate burdens of ozone well within recent satellite estimates. The Chemistry Climate Modelling Initiative model ozone budgets indicate that the net chemical production of ozone in the troposphere plateaued in the 1990s and has not changed since then inspite of increases in the burden. There has been a shift in net ozone production in the troposphere being greatest in the northern mid and high latitudes to the northern tropics, driven by the regional evolution of precursor emissions. An analysis of the evolution of tropospheric ozone through the 21st century reveals a large source of uncertainty associated with models themselves. This structural uncertainty is greatest in the near term (two to three decades), but emissions scenarios dominate uncertainty in the longer term (2050–2100) evolution of tropospheric ozone. This intrinsic model uncertainty prevents robust predictions of near-term changes in the tropospheric ozone burden, and we review how progress can be made to reduce this limitation. Archibald (2020) Science of the Anthropocene