Atmospheric/Air Chemistry

The Department of Meteorology and Atmospheric Science at Penn State University provides graduate research opportunities in air chemistry and climate change. Field studies are routinely carried out in many regions of the world to investigate trace gas emissions, transport, and deposition in rural and suburban environments. Of particular interest is the transformation of gases to particles and how such particles can directly and indirectly influence climate.

Information obtained from field investigations requires integration within existing numerical models. New numerical models are often developed to study atmospheric transport and chemical transformation of trace gases. Carbon cycle research involves flux tower and numerical modeling studies designed to determine the carbon sequestration provided by forests and agro-ecosystems. Paleoclimate investigations involve data analyses and numerical modeling activities to determine the history and future drivers of the Earth’s climate.

Opportunities are available for graduate students to develop and field-test new instrumentation to study air quality and regional climate change. Possibilities exist for graduate students to become involved with international research in places such as Canada (in the high Arctic), Brazil, Panama, Mexico, Senegal, and South Africa. 

In the News

Air Pollution Impedes Bees' Ability to Find Flowers, Washington Post (May 2008)


Dr. William Brune talks about the broad impacts that his research in understanding atmospheric composition and chemistry has on improving air quality, which would translate to improvements in world health and climate change. 

People specializing in this area


William H. Brune

Brune studies the atmosphere's oxidation chemistry by making measurements in field campaigns and then modeling the measurements with photochemical box models. These studies address fundamental questions of air quality near Earth's surface, of atmospheric effects of global pollution in the middle and upper troposphere, and of ozone destruction in the stratosphere. He, his research associates, and his students have developed instruments to measure atmospheric hydroxyl and hydroperoxyl radicals, OH reactivity (the inverse of the OH lifetime), potential aerosol mass, and the ozone production rate. Their Potential Aerosol Mass chambers are used by more than a dozen research groups for laboratory and field studies of particle formation and aging. He and his colleagues also assess atmospheric chemistry model uncertainty and the sensitivity of model outputs to model inputs. This research is focused on improving the understanding of atmospheric oxidation processes.

Join us as we explore the atmosphere's oxidation chemistry with field measurements, laboratory studies, and modeling. Be a valuable member in our scientific collaborations with other research groups around the world. Become an expert in an expanding research area that has significant implications for society, global change, and environmental policy.

Gregory S. Jenkins

Biomass burning, soils and lightning in Africa provide natural and anthropogenic sources of ozone to the free troposphere, which can influence air quality and increase net radiative surface forcing.  Mineral dust can act as a sink of tropospheric ozone through heterogeneous chemical processes.  I have been trying to understand how lightning in particular and mineral dust aerosols can act as sources and sinks of tropospheric ozone in regions downstream of continental Africa.

  • Jenkins, G. S., K. Mohr, V. R. Morris, O. Arino, 1997: The role of convective processes over the Zaire-Congo Basin to the Southern Hemispheric ozonemaximum.  Journal of Geophysical Research, 102.
  • Jenkins, G. S., 2000: TRMM satellite estimates of convective processes in Central Africa during September, October, November 1998: implications for elevated Atlantic tropospheric ozone, Geophysical Research Letters, 27, 1711-1714.
  • Ryu, J-H., G. S. Jenkins, 2005: Lightning-tropospheric ozone connections: EOF analysis of TCO and lightning data, Atmospheric Environment, 39, 5799-5805.
  • Jenkins, G. S., M. Camara, S. Ndiaye, 2008: Observational Evidence of Enhanced Middle/Upper Tropospheric Ozone via Convective Processes over the Equatorial Tropical Atlantic during the Summer of 2006, Geophys. Res. Lett., doi:10.1029/2008GL033954.
  • Jenkins, G. S., Robjhon, M., Smith. J., Clark. J., Mendes. L., 2012: The influence of the SAL on tropospheric ozone:  Results from Cape Verde during 2010. Geophys. Res. Lett.,39, 20, doi:10.1029/2012GL053532.
  • Jenkins, G. S. et al. 2013: Multi-site tropospheric ozone measurements across the north Tropical Atlantic during the summer of 2010, Atmospheric Environment 70, 131-148.
  • Jenkins, G. S., Ndiaye, S., Gueye, M., Fitzhugh, R., Smith J. W., Kebe, A., 2013:  Enhancement and depletion of lower/middle tropospheric ozone in Senegal during pre-monsoon and monsoon periods of summer 2008: Observations and Model results, J. Atmos. Chem. DOI: 10.1007/s10874-012-9240-7.
  • J. W. Smith, G. S. Jenkins and K. Pickering, 2014:  Quantifying African biomass burning ozone precursor transport and tropospheric ozone enhancement over the Eastern Equatorial Atlantic Ocean in June of 2006, J Atmospheric Chemistry.
  • Jenkins, G. S, M. Gueye, M.S. Drame, A Ndiaye, 2014: Evidence of a LNOX influence on middle/upper troposphere ozone mixing ratios at Dakar, Senegal during Northern Hemisphere Summer Season, Atmospheric Science Letters, doi: 10.1002/asl2.489.
  • Jenkins, G. S., Robjhon, M. L., Reyes A., Valentine, A., Neves, L, 2015:  Elevated Middle and Upper troposphere ozone observed downstream of Atlantic tropical cyclones, Atmospheric environment, Atmospheric Environment 118 (2015) 70-86.

Graduate Students

Jacob Tindan

My current research seeks to understand how Saharan dust emissions, and transport to the Sahel, the eastern United States, and the Caribbean has changed over the past decade, and will change in the future under the various climatic forcing scenarios.

In other works, I have examined the diurnal cycles of dust activities (dust optical depth and dust layer height) over the dust belt (North Africa, the Middle East, and Asia) using satellite, ground-based, and reanalysis products. Using reanalysis products from ERA5 and MERRA2, the meteorological and land surface conditions affecting the diurnal cycle of dust activities were also examined. In addition, I have also assessed the interannual variations in dust over some regions of North Africa, the Middle East, and the Indian Subcontinent. To understand the factors controlling trends in dust activities, some machine learning techniques (support vector machines and random forest regressions) were utilized. 

Manuscripts on these projects are already under review and others at various stages of completion. Results from these works have been presented in some conferences, such as the 102 annual meeting of the American Meteorological Society (AMS), and another abstract is submitted to the American Geophysical Union for the fall 2022 annual meeting. The results from these projects will significantly improve our current understanding of the spatial-temporal variability of dust over the dust belt, and their transport from North Africa to the United States and the Caribbean, Europe, and the Sahel and the Guinea Coast.