Meteorology and Climate Influences on Tropospheric Ozone: a Review of Natural Sources, Chemistry, and Transport Patterns

Abstract

Tropospheric ozone is a key air pollutant and greenhouse gas. Its fate strongly depends on meteorological conditions and therefore subject to climate change influences. Such dependences through biogenic, chemical, and dynamic processes on different spatiotemporal scales have been unraveled from observations and modeling studies. In this process-oriented review, we summarize three dominant pathways of meteorological and climatic impacts on tropospheric ozone and present their recent progress. The three pathways are influences through changes in the natural precursor emissions, the kinetics and partitioning of chemistry and deposition, and the transport of ozone and its precursors. Tropospheric ozone levels have shown significant global or regional responses to meteorological/climatic changes (e.g., changes in the Brewer-Dobson Circulation, the Hadley Circulation, and El Niño-Southern Oscillation) and can be explained through the conjunction of these pathways. Most recent model projections predict that future climate will increase surface ozone in polluted regions and decrease ozone at a global scale due to stronger ozone chemical loss. However, uncertainties in climate-ozone responses and limitations in model capability still challenge the magnitude and even the sign of such projections. We highlight the rising importance of future increase of stratosphere-troposphere exchange in modulating tropospheric ozone that may largely compensate the predicted chemical loss of tropospheric ozone burden. We also highlight that uncertainties in isoprene chemistry, biogenic emissions in changing CO 2 levels and vegetation, and interactions between ozone and vegetation may largely affect the surface ozone response to climate change. Future research and model improvements are required to fill these gaps.

Local and synoptic meteorological influences on daily variability in summertime surface ozone in eastern China

“…Relative humidity can influence ozone through various processes. Atmospheric water vapor can directly influence ozone concentrations by HO x (HO x = OH + H + peroxy radicals) chemistry in complicated ways (Zanis et al, 2002;Jacob and Winner, 2009;Lu et al, 2019b). Moreover, a higher relative humidity is usually associated with higher fractions of clouds, which can slow the photochemical production of surface ozone.…”

“…Wang et al, 2018). An increase of 1 %-3 % per year in surface ozone since 2000 is observed at urban and regional background sites in these three city clusters (Wang et al, 2012;Zhang et al, 2014;Ma et al, 2016;Sun et al, Published by Copernicus Publications on behalf of the European Geosciences Union. Gao et al, 2017) and at a global baseline station in western China (Xu et al, 2016).…”

2013–2019 increases of surface ozone pollution in China: anthropogenic and meteorological influences

“…Ozone is highest in summer when photochemistry is most active (Wang et al, 2017). Meteorological conditions play an important role in modulating ozone concentrations, not only through transport but also by affecting emissions and chemical rates (Jacob and Winner, 2009;Shen et al, 2016;Fu et al, 2019;Lu et al, 2019).…”

Development of the global atmospheric general circulation-chemistry model BCC-GEOS-Chem v1.0: model description and evaluation

“…There are still several limitations in this version that should be addressed in future model development. The current version of BCC-GEOS-Chem does not include full stratospheric chemistry mechanism, which is important for accurately modeling the evolution of ozone and its climate influences (Lu et al, 2019). We plan to implement the unified tropospheric-stratospheric chemistry extension (UCX) (Eastham et al, 2014), which is now the "Standard" mechanism for GEOS-Chem chemistry, into the next version of BCC-GEOS-Chem.…”

“…Atmospheric chemistry plays an indispensable role in the evolution of atmospheric gases and aerosols, and is also an essential component of the climate system due to its active interactions with atmospheric physics and biogeochemistry on various spatiotemporal scales. Climate modulates the natural emissions, chemical kinetics, and transport of atmospheric gases and aerosols, while changes in many of these constituents alter the radiative budgets of the climate system and also influence the biosphere (Jacob and Winner, 2009;Fiore et al, 2012;Lu et al, 2019). Climate-chemistry coupled models are indispensable tools to quantify climate-chemistry interactions and to predict future air quality.…”