Publication Abstracts

Laraia et al. 2013

Laraia, L., A.P. Ingersoll, M.A. Janssen, S. Gulkis, F. Oyafuso, and M. Allison, 2013: Analysis of Saturn's thermal emission at 2.2-cm wavelength: Spatial distribution of ammonia vapor. Icarus, 226, 641-654, doi:10.1016/j.icarus.2013.06.017.

This work focuses on determining the latitudinal structure of ammonia vapor in Saturn's cloud layer near 1.5 bars using the brightness temperature maps derived from the Cassini RADAR (Elachi et al., 2004) instrument, which works in a passive mode to measure thermal emission from Saturn at 2.2-cm wavelength. We perform an analysis of five brightness temperature maps that span epochs from 2005 to 2011, which are presented in a companion paper by Janssen et al. (2013a, this issue). The brightness temperature maps are representative of the spatial distribution of ammonia vapor, since ammonia gas is the only effective opacity source in Saturn's atmosphere at 2.2-cm wavelength. Relatively high brightness temperatures indicate relatively low ammonia relative humidity (RH), and vice versa. We compare the observed brightness temperatures to brightness temperatures computed using the Juno atmospheric microwave radiative transfer (JAMRT) program which includes both the means to calculate a tropospheric atmosphere model for Saturn and the means to carry out radiative transfer calculations at microwave frequencies. The reference atmosphere to which we compare has a 3×solar deep mixing ratio of ammonia (we use 1.352×10-4 for the solar mixing ratio of ammonia vapor relative to H2; see Atreya, 2010) and is fully saturated above its cloud base. The maps are comprised of residual brightness temperatures-observed brightness temperature minus the model brightness temperature of the saturated atmosphere.

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BibTeX Citation

@article{la05400l,
  author={Laraia, L. and Ingersoll, A. P. and Janssen, M. A. and Gulkis, S. and Oyafuso, F. and Allison, M.},
  title={Analysis of Saturn's thermal emission at 2.2-cm wavelength: Spatial distribution of ammonia vapor},
  year={2013},
  journal={Icarus},
  volume={226},
  pages={641--654},
  doi={10.1016/j.icarus.2013.06.017},
}

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RIS Citation

TY  - JOUR
ID  - la05400l
AU  - Laraia, L.
AU  - Ingersoll, A. P.
AU  - Janssen, M. A.
AU  - Gulkis, S.
AU  - Oyafuso, F.
AU  - Allison, M.
PY  - 2013
TI  - Analysis of Saturn's thermal emission at 2.2-cm wavelength: Spatial distribution of ammonia vapor
JA  - Icarus
VL  - 226
SP  - 641
EP  - 654
DO  - 10.1016/j.icarus.2013.06.017
ER  -

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