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On Earth’s habitability over the Sun’s main-sequence history: joint influence of space weather and Earth´s magnetic field evolution.
J. Varela,1⋆ A. S. Brun,2 A. Strugarek,2 V. Réville,3 P. Zarka4 and F. Pantellini5
1Universidad Carlos III de Madrid, Leganes, 28911 2Laboratoire AIM, CEA/DRF – CNRS – Univ. Paris Diderot – IRFU/DAp, Paris-Saclay, Gif-sur-Yvette Cedex, France, 91191 3IRAP, Université Toulouse III—Paul Sabatier, CNRS, CNES, Toulouse, France 4LESIA & USN, Observatoire de Paris, CNRS, PSL/SU/UPMC/UPD/UO, Place J. Janssen, Meudon, France, 92195 5LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, Meudon, France, 92195 Accepted XXX. Received YYY; in original form ZZZ
ABSTRACT
The aim of this study is to analyze the Earth habitability with respect to the direct exposition of the Earth atmosphere to the solar wind along the Sun’s evolution on the main sequence including the realistic evolution of the space weather conditions and the Earth magnetic field. The MHD code PLUTO in spherical coordinates is applied to perform parametric studies with respect to the solar wind dynamic pressure and the interplanetary magnetic field intensity for different Earth magnetic field configurations. Quiet space weather conditions may not impact the Earth habitability. On the other hand, the impact of interplanetary coronal mass ejections (ICME) could lead to the erosion of the primary Earth atmosphere during the Hadean eon. A dipolar field of 30 µT is strong enough to shield the Earth from the Eo-Archean age as well as 15 and 5 µT dipolar fields from the MesoArchean and Meso-Proterozoic, respectively. Multipolar weak field period during the Meso-Proterozoic age may not be a threat
for ICME-like space weather conditions if the field intensity is at least 15 µT and the ratio between the quadrupolar (Q) and dipolar (D) coefficients is Q D ≤ 0.5. By contrast, the Earth habitability in the Phanerozoic eon (including the present time) can be hampered during multipolar low field periods with a strength of 5 µT and Q D
≥ 0.5 associated to geomagnetic reversals. Consequently, the effect of the solar wind should be considered as a possible driver of Earth´s habitability. Key words: Earth magnetosphere – space weather – CME – Earth habitability
1 INTRODUCTION
The analysis of the space weather in the last decades has demonstrated the essential role of the solar wind (SW) and interplanetary magnetic field (IMF) on the Earth magnetosphere, ionosphere, thermosphere and exosphere state (Poppe, B.B. & Jorden, K.P. 2006; González Hernández, I. et al. 2014). That means, space weather conditions can introduce constraints on the habitability of the Earth and exoplanets with respect to the shielding provided by planetary magnetospheres, avoiding the sterilizing effect of the stellar wind on the surface (Gallet, F. et al. 2017; Linsky, J. 2019; Airapetian, V. S. et al. 2020; Strugarek et al. 2015; Garraffo, C. et al. 2016; Varela et al.
2022b). Recent studies also indicate the solar wind may cause the depletion of the Earth atmosphere, particularly volatile molecules such as water by thermal and non-thermal escape (Lundin, R. et al. 2007; Moore, T. E. & Khazanov, G. V. 2010; Jakosky, B. M. et al. 2015) as well as lead to damages on biological structures (Sihver &
Mortazavi 2021; Zenchenko & Breus 2021).// Continue reading here : https://arxiv.org/pdf/2311.03720.pdf
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Dear Colleagues,
Over the past decade, a growing number of studies have been focusing on the association between geomagnetic activity and other space weather phenomena (like space storms, solar proton events, solar flares, cosmic rays activity, Pc1 and Pc4-Pc5 geomagnetic pulsations, and high-speed solar wind) and human health, especially on the cardiovascular system. In recent years, the created databases of environmental data give an opportunity to evaluate the complex effect of space weather and atmospheric conditions on human health,…
Prof. Dr. JONE VENCLOVIENE