Europlanet Science Congress 2020
Virtual meeting
21 September – 9 October 2020
Europlanet Science Congress 2020
Virtual meeting
21 September – 9 October 2020
EPSC Abstracts
Vol.14, EPSC2020-191, 2020
https://doi.org/10.5194/epsc2020-191
Europlanet Science Congress 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Atmospheric dynamics on terrestrial planets with eccentric orbits

Ilai Guendelman and Yohai Kaspi
Ilai Guendelman and Yohai Kaspi
  • Weizmann Institute of Science, Earth and Planetary Science, Beer Sheva, Israel (ilai.guendelman@weizmann.ac.il)

The insolation a planet receives from its parent star is the main engine of the climate and depends on the planet's orbital configuration. Planets with non-zero obliquity and eccentricity experience seasonal insolation variations. As a result, the climate exhibits a seasonal cycle, with its strength depending on the orbital configuration and atmospheric characteristics. In this study, using an idealized general circulation model, we examine the climate response to changes in eccentricity for both zero and non-zero obliquity planets. In the zero obliquity case, a comparison between the seasonal response to changes in eccentricity and perpetual changes in the solar constant shows that the seasonal response strongly depends on the orbital period and radiative timescale. More specifically, using a simple energy balance model, we show the importance of the latitudinal structure of the radiative timescale in the climate response. We also show that the response strongly depends on the atmospheric moisture content. The combination of an eccentric orbit with non-zero obliquity is complex, as the insolation also depends on the perihelion position. Although the detailed response of the climate to variations in eccentricity, obliquity, and perihelion is involved, the circulation is constrained mainly by the thermal Rossby number and the maximum temperature latitude. Finally, we discuss the importance of different planetary parameters that affect the climate response to orbital configuration variations.

How to cite: Guendelman, I. and Kaspi, Y.: Atmospheric dynamics on terrestrial planets with eccentric orbits, Europlanet Science Congress 2020, online, 21 September–9 Oct 2020, EPSC2020-191, https://doi.org/10.5194/epsc2020-191, 2020