Publication Abstracts

Menon et al. 2000

Menon, S., V.K. Saxena, and B.D. Logie, 2000: Chemical heterogeneity across cloud droplet size spectra in continental and marine air masses. J. Appl. Meteorol., 39, 887-903, doi:10.1175/1520-0450(2000)039<0887:CHACDS>2.0.CO;2.

Variations in the chemistry of cloud droplets of different sizes are predicted in models, however, measurements made in natural clouds to verify this are extremely limited. During the spring of 1995 and summers of 1995-96, a size-fractionating version of the California Institute of Technology active strand cloud water collector was operated on a mountain-top platform in Mt. Mitchell State Park, North Carolina (35° 44' 05" N 82° 17' 15"W), USA, to examine differences in drop chemistry between large and small cloud droplets. The size fractionated measurements were also compared to the chemical composition collected from a passive string type collector that collects bulk samples. Back-trajectory analysis was used to categorize the source of cloud forming air masses that arrived at the site as polluted continental, continental and marine. The differences in cloud drop acidity, cloud liquid water, cloud condensation nuclei concentration, cloud droplet number concentration and cloud droplet effective radii were investigated for these different air masses. On an average, smaller drops were more enriched in SO42-, NO3-, NH4+ and H+; whereas larger droplets had higher values of Na+, Ca2+, Mg2+. However, samples were collected where the reverse was true. In this study, cloud droplet chemical inhomogeneity between droplet sizes and the effect of air mass origin on the variations in the chemical composition were examined. Smaller droplets were found to be more acidic than larger droplets for both marine and polluted continental air masses. The sodium content was the highest in the larger drops for marine events. The sulfate content in both the larger and smaller droplets were the highest for air masses that were from the polluted continental sector. Slightly higher solute concentrations for the larger droplet size range were found for events caused by orographic lifting, whereas, for cloud events influenced by frontal activity, higher solute concentrations were found for the smaller drop size range.

Export citation: [ BibTeX ] [ RIS ]

BibTeX Citation

  author={Menon, S. and Saxena, V. K. and Logie, B. D.},
  title={Chemical heterogeneity across cloud droplet size spectra in continental and marine air masses},
  journal={J. Appl. Meteorol.},

[ Close ]

RIS Citation

ID  - me03000u
AU  - Menon, S.
AU  - Saxena, V. K.
AU  - Logie, B. D.
PY  - 2000
TI  - Chemical heterogeneity across cloud droplet size spectra in continental and marine air masses
JA  - J. Appl. Meteorol.
VL  - 39
SP  - 887
EP  - 903
DO  - 10.1175/1520-0450(2000)039%3C0887%3ACHACDS%3E2.0.CO;2
ER  -

[ Close ]

• Return to 2000 Publications

• Return to Publications Homepage