The Tropospheric Composition Program (TCP) studies the composition of the lower atmosphere with a particular emphasis on the impact of tropospheric ozone and aerosols on air quality and climate from local to global scales. This includes the need to understand the precursor emissions, chemical transformations, and meteorological factors that influence their formation and atmospheric distributions. Working in concert with international partners, TCP strives to develop an integrated observing system for tropospheric composition, which includes chemical transport models, as well as satellite, airborne, and ground-based observations of tropospheric composition. This integrated observing system is fundamental to create a better understanding of air quality and climate.
The composition of the atmosphere is one of the most rapidly changing components of the Earth system. As such, it often provides the first clues to changes in human activity and ecosystem responses that can have both immediate and long-term impacts. Many of these impacts can be categorized into short-term issues related to Air Quality and long-term effects of Climate Change. Air Quality is largely driven by local factors, but it is not immune to large-scale impacts related to transboundary pollution transport between neighboring countries and the collective impact of human activity on changes in hemispheric and global background concentrations of key pollutants. Climate Change relates to global-scale trends in long-lived greenhouse gases, but the driving emissions are highly variable in time and space, requiring attention at local-to-regional scales. Both involve outcomes that depend on the intersection of anthropogenic and natural emissions.
Along with the availability of the first satellite observations for atmospheric chemical constituents came efforts to diagnose emissions. Over the last two decades, increasingly sophisticated top-down emission assessment methods based on satellite observations have been developed to compare with traditional bottom-up emissions assessments. Such bottom-up emissions are more detailed, but they rely on assumptions in order to scale up each emissions sector using statistics on activity levels and average emission factors for specific processes. Observation-based, top-down efforts have typically focused on individual species (e.g., CO, NO CO 2R R 2R R , SO 4R R 3R R 2R R , NH , CH , ) and have provided insight on long-term emission trends. With the introduction of geostationary satellite observations, additional insight into diurnal variability in emissions is expected. Deducing these finer-scale emission patterns and the resulting atmospheric pollutant distributions will lead to a better understanding of local and regional air quality issues, improved modeling of the relationship between primary emissions and secondary pollutants (e.g., ozone and particulate matter), and more informed decision making to support pollution mitigation strategies.
The NASA Tropospheric Composition Program (TCP) is soliciting proposals for participation in the Airborne and Satellite Investigation of Asian Air Quality (ASIA-AQ) airborne campaign to be conducted in at least three Asian locations during January - March of 2024. This solicitation is looking for scientists to provide measurements and modeling to support the instrumented NASA research aircraft required to accomplish the ASIA-AQ research goals. In this airborne campaign, the NASA DC-8 will provide observations from near surface to ~12.5 km, and the NASA GV will provide mapping remote sensing observations from ~8.5 km. Salient details of the ASIA-AQ campaign are summarized below. For a more detailed description of the effort, proposers are referred to the ASIA-AQ white paper available at 28TU aq/content/ASIA-AQ_White_Paper U28T https://espo.nasa.gov/asia.
Deadlines:
- Notice of Intent: Sep 1, 2022
- Proposal: Oct 4, 2022