Air quality research is in a period of rich, multi-perspective observations. The constellation of geostationary air quality satellites has dramatically expanded information from space, complementing the long-term record from instruments in low-earth orbit. Ground monitoring has expanded globally with greater investments in regulatory networks. The density of ground monitoring has also benefitted from the proliferation of small sensors that continue to improve in quality. These expanded observations provide unprecedented detail. They also enhance the potential for the integration of chemical observations and meteorological context.

Air quality outcomes depend heavily on synoptic conditions as well as local-scale dynamics related to land-sea breezes, mountain-valley circulations, and urban-rural contrasts. In addition to these influences, capturing the role of boundary layer meteorology remains one of the most critical elements in understanding air quality chemistry and the relationship between conditions aloft and impacts to surface air quality. Ground observations show clear temporal gradients related to boundary layer mixing, and aircraft profiles have consistently shown that large vertical gradients and even layering can exist in what is often assumed to be a well-mixed boundary layer.

Despite the strong relationship between air quality chemistry and meteorology, the deliberate sampling of chemistry and urban-scale dynamics with an intent to improve predictability of both is lacking. NASA’s B777 research aircraft opens new opportunities in remote sensing that enable concurrent measurements of chemistry and meteorology in previously untested combinations. Coupled with in situ sampling by a second profiling aircraft, the resulting observations would be able to constrain earth system models in ways that could more effectively isolate the chemical and dynamical factors affecting air quality and ask broader questions about the coupling between earth system components (e.g., land surface, atmosphere). The interpretation of satellite observations would also be expected to benefit from the improved prediction of gradients in the composition of the lower atmosphere. The resulting view from space combined with models will enable better assessment of the impact of megacities and urban settings across local, regional, and global scales. Examples from previous field studies and thoughts on future opportunities for expanded observations will be discussed.

*Refreshments: 12-12:30 PM, ES&T Atrium