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Title: Surface Variability of Short-wavelength Radiation and Temperature on Exoplanets around M Dwarfs

Abstract

It is a common practice to use 3D General Circulation Models (GCM) with spatial resolution of a few hundred kilometers to simulate the climate of Earth-like exoplanets. The enhanced albedo effect of clouds is especially important for exoplanets in the habitable zones around M dwarfs that likely have fixed substellar regions and substantial cloud coverage. Here, we carry out mesoscale model simulations with 3 km spatial resolution driven by the initial and boundary conditions in a 3D GCM and find that it could significantly underestimate the spatial variability of both the incident short-wavelength radiation and the temperature at planet surface. Our findings suggest that mesoscale models with cloud-resolving capability be considered for future studies of exoplanet climate.

Authors:
;  [1];  [2]; ;  [3]
  1. Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing 100084 (China)
  2. Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, QC H3A 0B9 (Canada)
  3. National Center for Atmospheric Research, Boulder, CO (United States)
Publication Date:
OSTI Identifier:
22654518
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 837; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BOUNDARY CONDITIONS; CLOUDS; DWARF STARS; GENERAL CIRCULATION MODELS; PLANETS; SATELLITE ATMOSPHERES; SATELLITES; SIMULATION; SPATIAL RESOLUTION; SURFACES; THREE-DIMENSIONAL CALCULATIONS; WAVELENGTHS

Citation Formats

Zhang, Xin, Tian, Feng, Wang, Yuwei, Dudhia, Jimy, and Chen, Ming, E-mail: tianfengco@tsinghua.edu.cn. Surface Variability of Short-wavelength Radiation and Temperature on Exoplanets around M Dwarfs. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA62FC.
Zhang, Xin, Tian, Feng, Wang, Yuwei, Dudhia, Jimy, & Chen, Ming, E-mail: tianfengco@tsinghua.edu.cn. Surface Variability of Short-wavelength Radiation and Temperature on Exoplanets around M Dwarfs. United States. doi:10.3847/2041-8213/AA62FC.
Zhang, Xin, Tian, Feng, Wang, Yuwei, Dudhia, Jimy, and Chen, Ming, E-mail: tianfengco@tsinghua.edu.cn. Fri . "Surface Variability of Short-wavelength Radiation and Temperature on Exoplanets around M Dwarfs". United States. doi:10.3847/2041-8213/AA62FC.
@article{osti_22654518,
title = {Surface Variability of Short-wavelength Radiation and Temperature on Exoplanets around M Dwarfs},
author = {Zhang, Xin and Tian, Feng and Wang, Yuwei and Dudhia, Jimy and Chen, Ming, E-mail: tianfengco@tsinghua.edu.cn},
abstractNote = {It is a common practice to use 3D General Circulation Models (GCM) with spatial resolution of a few hundred kilometers to simulate the climate of Earth-like exoplanets. The enhanced albedo effect of clouds is especially important for exoplanets in the habitable zones around M dwarfs that likely have fixed substellar regions and substantial cloud coverage. Here, we carry out mesoscale model simulations with 3 km spatial resolution driven by the initial and boundary conditions in a 3D GCM and find that it could significantly underestimate the spatial variability of both the incident short-wavelength radiation and the temperature at planet surface. Our findings suggest that mesoscale models with cloud-resolving capability be considered for future studies of exoplanet climate.},
doi = {10.3847/2041-8213/AA62FC},
journal = {Astrophysical Journal Letters},
number = 2,
volume = 837,
place = {United States},
year = {Fri Mar 10 00:00:00 EST 2017},
month = {Fri Mar 10 00:00:00 EST 2017}
}
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