English

The Effect of Ocean Salinity on Climate and Its Implications for Earth's Habitability

Earth and Planetary Astrophysics 2022-05-16 v1 Atmospheric and Oceanic Physics Geophysics

Abstract

The influence of atmospheric composition on the climates of present-day and early Earth has been studied extensively, but the role of ocean composition has received less attention. We use the ROCKE-3D ocean-atmosphere general circulation model to investigate the response of Earth's present-day and Archean climate system to low vs. high ocean salinity. We find that saltier oceans yield warmer climates in large part due to changes in ocean dynamics. Increasing ocean salinity from 20 g/kg to 50 g/kg results in a 71% reduction in sea ice cover in our present-day Earth scenario. This same salinity change also halves the pCO2_2 threshold at which Snowball glaciation occurs in our Archean scenarios. In combination with higher levels of greenhouse gases such as CO2_2 and CH4_4, a saltier ocean may allow for a warm Archean Earth with only seasonal ice at the poles despite receiving 20% less energy from the Sun.

Keywords

Cite

@article{arxiv.2205.06785,
  title  = {The Effect of Ocean Salinity on Climate and Its Implications for Earth's Habitability},
  author = {Stephanie L. Olson and Malte F. Jansen and Dorian S. Abbot and Itay Halevy and Colin Goldblatt},
  journal= {arXiv preprint arXiv:2205.06785},
  year   = {2022}
}

Comments

Accepted for publication in Geophysical Research Letters 04/19/22