Publication Abstracts

Rossow et al. 1990

Rossow, W.B., A.D. Del Genio, and T. Eichler, 1990: Cloud-tracked winds from Pioneer Venus OCPP images. J. Atmos. Sci., 47, 2053-2084, doi:10.1175/1520-0469(1990)047<2053:CTWFVO>2.0.CO;2.

Analysis of ultraviolet image sequences, obtained from the Pioneer Venus Orbiter Cloud Photopolarimeter and covering five 80-day periods from 1979-1985, provides the first climatological description of the cloud top circulation on Venus. The average zonal winds can be characterized as a 5-day retrograde rotation of the whole cloud-level atmosphere with weak "jets" at middle to high latitudes. Both the midlatitude and equatorial zonal winds vary by about 5-8 m/s over time spans of 1-6 years. The average meridional circulation is poleward in both hemispheres up to at least 60° latitude, consistent with the presence of a thermally direct Hadley circulation associated with the clouds. The strength of the Hadley circulation also varies with time. Four wave modes are clearly identified: a diurnal solar tide, a semi-diurnal tide, a "4-day equatorial" wave, and a "5-day midlatitude" wave. The semidiurnal tide appears to have an amplitude of about 5 m/s and to be approximately constant with time; the diurnal tide varies in amplitude from about 10 m/s to less than 5 m/s. Both tides have phases such that maximum zonal windspeeds occur near the evening terminator. The "4-day" wave is wavenumber 1 and has an amplitude of about 5 m/s that peaks at the equator and varies with time; in 1982 no wave with this period was apparent in the data. This wave mode is identified as a Kelvin mode by Del Genio and Rossow. The "5-day" wave is wavenumber 1 and has an amplitude of about 5 m/s that peaks at midlatitudes and varies in time; in 1982 no wave with this period was apparent. This wave mode is identified as an internal Rossby-Haurwitz mode.

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BibTeX Citation

@article{ro03400p,
  author={Rossow, W. B. and Del Genio, A. D. and Eichler, T.},
  title={Cloud-tracked winds from Pioneer Venus OCPP images},
  year={1990},
  journal={J. Atmos. Sci.},
  volume={47},
  pages={2053--2084},
  doi={10.1175/1520-0469(1990)047%3C2053%3ACTWFVO%3E2.0.CO;2},
}

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RIS Citation

TY  - JOUR
ID  - ro03400p
AU  - Rossow, W. B.
AU  - Del Genio, A. D.
AU  - Eichler, T.
PY  - 1990
TI  - Cloud-tracked winds from Pioneer Venus OCPP images
JA  - J. Atmos. Sci.
VL  - 47
SP  - 2053
EP  - 2084
DO  - 10.1175/1520-0469(1990)047%3C2053%3ACTWFVO%3E2.0.CO;2
ER  -

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