Thermal Habitability: Connection with the Earth’s Motion Around the Sun

Abstract

This book investigates the billion-year takeover of planet Earth by its organisms and ecosystems. This chapter examines both the conditions that make the Earth’s temperature generally suitable for organisms, which determines the thermal habitability of the planet, and the effects of ecosystems on temperature. The chapter considers successively: the thermal limits for growth and survival, and the temperatures on Earth, Venus, Mars and the Moon; the sources of energy at the surface of Earth; the solar radiation flux that reaches Earth; the fate of the solar radiation absorbed by the Earth System; the effects of the absorbed solar radiation on the climate system; how the atmosphere and Earth’s distance from the Sun contribute to set the range of temperatures that occur on Earth; and the long-term controls on Earth’s temperature. It examines the latitudinal, diurnal and seasonal variations in the solar radiation flux and their effects on organisms. The presence of the Moon likely favoured the general occurrence on Earth of climatic conditions suitable for organisms since their establishment on the planet about 4 billion years ago. The chapter also describes the atmospheric and oceanic circulations, and their combined effects on the redistribution of heat on the planet. It considers the faint young Sun paradox and the long-term control of the concentration of atmospheric carbon dioxide. The chapter ends with a summary of key points concerning the interactions between the Solar System, Earth, its temperature, and its ecosystems.

Figure Credits

Fig. 3.1 Original. Figure 3.1 is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.

Fig. 3.2 Modified after Figure 2-12 of Ackerman and Knox (2017). With permission from Profs. Steven A. Ackerman, University of Wisconsin-Madison, USA, and John A. Knox, University of Georgia, USA.

Fig. 3.3 Original. Figure 3.3 is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla.

Fig. 3.4 This work, Figure 3.4, is a derivative of https://commons.wikimedia.org/w/index.php?curid=9389402 by Jalanpalmer (talk) https://commons.wikimedia.org/wiki/User:Jalanpalmer and (https://commons.wikimedia.org/wiki/User_talk:Jalanpalmer), in the public domain. I, Mohamed Khamla, release this work in the public domain.

Fig. 3.5a This work, Figure 3.5a is a derivative of https://commons.wikimedia.org/wiki/File%3AAtmosphCirc2.png by DWindrim, used under GNU FDL and CC BY-SA 3.0. Figure 3.5a is licensed under GNU FDL and CC BY-SA 3.0 by Mohamed Khamla.

Fig. 3.5b,c https://commons.wikimedia.org/wiki/File:Mslp-jja-djf.png by William M. Connolley https://en.wikipedia.org/wiki/User:William_M._Connolley, used under GNU FDL and CC BY-SA 3.0.

Fig. 3.6 This work, Figure 3.6 is a derivative of https://en.wikipedia.org/wiki/File:Corrientes-oceanicas.png by Dr. Michael Pidwirny (see http://www.physicalgeography.net), in the public domain, U.S. Government publication. The original position the Kuroshio current was slightly modified. I, Mohamed Khamla, release this work in the public domain.

Fig. 3.7a Original. Figure 3.7a is licensed under CC BY-SA 4.0 by Philippe Bertrand, Louis Legendre and Mohamed Khamla

Fig. 3.7b https://science.nasa.gov/earth-science/oceanography/physical-ocean/ocean-surface-topography/the-dynamic-pacific-ocean by NASA’s Jet Propulsion Laboratory, in the public domain.

Fig. 3.8 This work, Figure 3.8, is a derivative of https://commons.wikimedia.org/wiki/File:Conveyor_belt.svg by Avsa https://commons.wikimedia.org/wiki/User:Avsa, used under GNU FDL and CC BY-SA 3.0, and https://commons.wikimedia.org/wiki/File:Oceans.png by Saperaud, used under GNU FDL and CC BY-SA 3.0. Figure 3.8 is licensed under GNU FDL and CC BY-SA 3.0 by Mohamed Khamla.