EvGeo

Geological Evolution of a Habitable Planet

Giovanni Muttoni - The State University of Milan

Cooper : Detach!
Brand : Goodbye TARS.
TARS : Good-bye Dr. Brand. See you on the other side Coop.
Cooper : See you there slick!

LECTURES (* are mandatory)

Part 0. Introduction

Class discussion on the basic requirements for simple life and complex life.

Introductory icebreaker lecture: how many Earths?

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Part I. Setting the scene: the first half billion years. Formation of a wet rocky planet

Early Earth 4.56-3.9 By *

Halliday, A. N. (2006), The origin of the Earth-What's new?, Elements, 2(4), 205-210.

History of the Hadean&Archean

Early Earth additional lectures

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Part II. Liquid water: origin

Origin of Water *

Welcome on a Comet!

Wet Stardust?

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Part III. Liquid water: maintenance. The long-term carbon cycle, planetary albedo and other climatic nuisances

III.1 Zonal climate, plate tectonics & Earth's thermostat

Without the radiative forcing supplied by CO2 and the other noncondensing greenhouse gases, the terrestrial greenhouse would collapse, plunging the global climate into an icebound Earth state.

Energy balance without CO2

Energy balance with CO2

CO2 survival guide

WHY DO WE NEED A CO2 OUTPUT? *

Co2 buidup - Colab simulator

Could oceans ever boil off?

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III.2 The role of planetary albedo

The building of polar ice has the effect to amplificate – through enhanced planetary albedo – global cooling resulting from the reduction of greenhouse gases via CO2 weathering consumption of mafic rocks in the tropical humid belt.

Kent, D.V., Muttoni, G. Latitudinal land–sea distributions and global surface albedo since the Cretaceous. Palaeogeography, Palaeoclimatology, Palaeoecology 585, 110718, 2022.

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Part IV. Liquid water: climate extremes

...expectations are that the silicate weathering thermostat would always be operative at the high temperature end and act to limit global overheating. However, at times when continental drift focused the weathering-prone landmasses in the pCO2-insensitive equatorial belt, the low range of the thermostat could become decoupled from global climate, allowing Earth to descend into glacial modes of varying severity.

Snowball Earth *

Hoffman, P. F., A. J. Kaufman, G. P. Halverson, and D. P. Schrag (1998), A Neoproterozoic snowball earth, science, 281(5381), 1342-1346.

Hoffman, P. F., and D. P. Schrag (2002), The snowball Earth hypothesis: testing the limits of global change, Terra nova, 14(3), 129-155.

Documentary 'Snowball Earth'

From the Early Eocene Climatic Optimum to the Neogene Ice Age *

Kent, D. V., and G. Muttoni (2008), Equatorial convergence of India and early Cenozoic climate trends, Proceedings of the National Academy of Sciences, 105(42), 16065-16070.

Kent, D. V., and G. Muttoni (2013), Modulation of Late Cretaceous and Cenozoic climate by variable drawdown of atmospheric pCO 2 from weathering of basaltic provinces on continents drifting through the equatorial humid belt, Climate of the Past, 9(2), 525-546.

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Part V. Oxygen

The G.O.E. and the N.O.E. *

Kump, L. R. (2008), The rise of atmospheric oxygen, Nature, 451(7176), 277.

Shields-Zhou, G., and L. Och (2011), The case for a Neoproterozoic oxygenation event: geochemical evidence and biological consequences, GSA Today, 21(3), 4-11.

LECTURES

Part VI. Earth's magnetic shield

Magnetic shielding of atmosphere *

Tarduno, J. A., R. D. Cottrell, W. J. Davis, F. Nimmo, and R. K. Bono (2015), A Hadean to Paleoarchean geodynamo recorded by single zircon crystals, Science, 349(6247), 521-524.

Tarduno, J. A., E. G. Blackman, and E. E. Mamajek (2014), Detecting the oldest geodynamo and attendant shielding from the solar wind: Implications for habitability, Physics of the Earth and Planetary Interiors, 233, 68-87.

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Part VII. From simple to complex life

Knoll, A. H. (2014), Paleobiological perspectives on early eukaryotic evolution, Cold Spring Harbor Perspectives in Biology, 6(1), a016121.

Early life forms:

Schopf, J. W. (2006), The first billion years: When did life emerge?, Elements, 2(4), 229-233. *

Virtual Field Trip to Dresser Formation *

Rapid emergence of life shown by discovery of 3,700-million-year-old stromatolites in SW Greenland

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Ediacara Day

Students' presentations

(see Students page, top left)

Pick your favourite beast

Trip to Mistaken Point *

Brasier, M., and J. Antcliffe (2004), Decoding the Ediacaran enigma, Science, 305(5687), 1115-1117.

Xiao, S., and M. Laflamme (2009), On the eve of animal radiation: phylogeny, ecology and evolution of the Ediacara biota, Trends in Ecology & Evolution, 24(1), 31-40.

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Part VIII. Evolution of life: the role of catastrophism

The punctuated equilibrium theory of Gould and Eldredge,1993

Jay Gould, S., and N. Eldredge (1993), Punctuated equilibrium comes of age, Nature, 366(6452), 223.

Case Study #1: The P/T boundary *

Lane, N. (2007), Reading the book of death, Nature, 448(7150), 122-125.

Docu 'The day Earth nearly ended'

Case Study #2: The K/T boundary *

Alvarez+1980

Hildebrand+1991

The First Day of the Cenozoic

Richards+ (see also lecture below)

Pierazzo, E., and N. Artemieva (2012), Local and global environmental effects of impacts on Earth, Elements, 8(1), 55-60.

LECTURES

Part IX. The last two million years: how humans conquered planet Earth

Ice Ages & First hominin colonization of Eurasia. On the importance of migrations for survival and evolution.

Muttoni, G., G. Scardia, and D. V. Kent (2018), Early hominins in Europe: The Galerian migration hypothesis, Quaternary Science Reviews, 180, 1-29.

Muttoni, G., and Kent, D.V. (2024). Hominin population bottleneck coincided with migration from Africa during the Early Pleistocene ice age transition. Proc Natl Acad Sci U S A. 26;121(13)

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Part X. Final Wrap-up: The importance of the Earth's characteristics for the evolution of complex life: implications for finding extraterrestrial civilizations

Discussion on the Drake equation and the Fermi paradox.

The Drake equation estimates how many ACCs there are in our galaxy. It is formulated as93:

where

R* = number of new stars formed per year,

fp = the fraction of stars with planetary systems,

ne = the average number of planets that could support life (habitable planets) per planetary system,

fl = the fraction of habitable planets that develop primitive life,

fi = the fraction of planets with life that evolve intelligent life and civilizations,

fc = the fraction of civilizations that become ACCs, L = the length of time that ACCs broadcast radio into space.

...and the importance of plate tectonics

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EXERCISES