Journal cover Journal topic
Earth System Dynamics An interactive open-access journal of the European Geosciences Union

Journal metrics

  • IF value: 3.635 IF 3.635
  • IF 5-year<br/> value: 3.869 IF 5-year
    3.869
  • CiteScore<br/> value: 4.15 CiteScore
    4.15
  • SNIP value: 0.995 SNIP 0.995
  • SJR value: 2.742 SJR 2.742
  • IPP value: 3.679 IPP 3.679
  • h5-index value: 21 h5-index 21
https://doi.org/10.5194/esd-2017-84
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
10 Oct 2017
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Earth System Dynamics (ESD).
Two drastically different climate states on an Earth-like terra-planet
Sirisha Kalidindi1,2, Christian H. Reick1, Thomas Raddatz1, and Martin Claussen1,3 1Max Planck Institute for Meteorology, Bundesstraße 53, 20146 Hamburg, Germany
2International Max Planck Research School on Earth System Modelling, Bundesstraße 53, 20146 Hamburg, Germany
3Center for Earth System Research and Sustainability, Universität Hamburg, Bundesstraße 53, 20146 Hamburg, Germany
Abstract. We study an Earth-like terra-planet with an overland recycling mechanism bringing fresh water back from higher latitudes to the lower latitudes. By performing model simulations for such a planet we find two drastically different climate states for the same set of boundary conditions and parameter values: A Cold and Wet (CW) state (present-day Earth-like climate) with dominant low-latitude precipitation and, a Hot and Dry (HD) state with only high-latitude precipitation. We notice that for perpetual equinox conditions, both climate states are stable below a certain threshold value of background soil albedo while above the threshold only the CW state is stable. Starting from the HD state and increasing background soil albedo above the threshold causes an abrupt shift from the HD state to the CW state resulting in a sudden cooling of about 35 °C globally which is of the order of the temperature difference between the present-day and the Snowball Earth state. In contrast to the Snowball Earth instability, we find that the sudden cooling in our study is driven by the cloud albedo feedback rather than the snow-albedo feedback. Also, when albedo in the CW state is reduced back to zero the terra-planet does not display a closed hysteresis. This is due to the high cloud cover in the CW state hiding the surface from solar irradiation. As a result, this reduction of background surface albedo has only a minor effect on the top of the atmosphere radiation balance, thereby making it impossible to heat the planet sufficiently strongly to switch back to the HD state. Additional simulations point to a similar abrupt transition from HD state to the CW state for non-zero obliquity which is the only stable state in this configuration. Our study also has implications for the habitability of Earth-like terra-planets. At the inner edge of the habitable zone, the higher cloud cover in the CW state cools the planet and may prevent the onset of a runaway greenhouse state. At the outer edge, the resupply of water at lower latitudes stabilizes the greenhouse effect and keeps the planet in the HD state and may prevent water from getting trapped at higher latitudes in frozen form. Overall, the existence of bi-stability in the presence of an overland recycling mechanism hints at the possibility of a wider habitable zone for Earth-like terra-planets at lower obliquities.

Citation: Kalidindi, S., Reick, C. H., Raddatz, T., and Claussen, M.: Two drastically different climate states on an Earth-like terra-planet, Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2017-84, in review, 2017.
Sirisha Kalidindi et al.
Sirisha Kalidindi et al.
Sirisha Kalidindi et al.

Viewed

Total article views: 142 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
115 25 2 142 1 1

Views and downloads (calculated since 10 Oct 2017)

Cumulative views and downloads (calculated since 10 Oct 2017)

Viewed (geographical distribution)

Total article views: 142 (including HTML, PDF, and XML)

Thereof 142 with geography defined and 0 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 17 Oct 2017
Publications Copernicus
Download
Short summary
Using climate simulations, we investigate the role of water recycling in shaping the climate of low-obliquity Earth-like terra-planets. By such a mechanism feeding water back from the extra-tropics to the tropics, the planet can assume two drastically different climate states differing by more than 35 K in global temperature. We describe the bifurcation between the two states occurring upon changes in surface albedo and argue that the bi-stability hints to a wider habitable zone for such planets.
Using climate simulations, we investigate the role of water recycling in shaping the climate of...
Share