Deep convection as a source of new particles in the midlatitude upper troposphere

Cynthia H. Twohy, Charles F. Clement, Bruce W. Gandrud, Andrew J. Weinheimer, Teresa L. Campos, Darrel Baumgardner, William H. Brune, Ian Faloona, Glen W. Sachse, Stephanie A. Vay, David Tan

Research output: Contribution to journalArticlepeer-review

84 Scopus citations


[1] A case study of new particle formation in the region downwind of a mesoscale convective system stretching across much of the central United States is presented. Airborne measurements were made of condensation nuclei (CN), cloud particle surface area, water vapor, and other gases. CN concentrations were greatly enhanced above and downwind of the cirrus anvil, with maximum concentrations of 45,000 per standard cm3. Volatility and electron microscope measurements indicated that most of the particles were likely to be small sulfate particles. The enhancement extended over at least a 600-km region. Multivariate statistical analysis revealed that high CN concentrations were associated with surface tracers, as well as convective elements. Convection apparently brings gas-phase particle precursors from the surface to the storm outflow region, where particle nucleation is favored by the extremely low temperatures. Simple calculations showed that deep convective systems may contribute to a substantial portion of the background aerosol in the upper troposphere at midlatitudes.

Original languageEnglish (US)
Pages (from-to)AAC 6-1-AAC 6-10
JournalJournal of Geophysical Research Atmospheres
Issue number21
StatePublished - Jan 1 2002

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Forestry
  • Oceanography
  • Aquatic Science
  • Ecology
  • Water Science and Technology
  • Soil Science
  • Geochemistry and Petrology
  • Earth-Surface Processes
  • Atmospheric Science
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Palaeontology


Dive into the research topics of 'Deep convection as a source of new particles in the midlatitude upper troposphere'. Together they form a unique fingerprint.

Cite this