What makes a planet habitable?
GEOS 22060 / GEOS 32060 / ASTR 45900


Class: Mondays, 4pm-6pm. Hinds 451.
Office hours: Mondays, 9am-10am. Hinds 467.
Note that there will be no office hours on Monday 22 Feb. Extra office hours on Tuesday 16 Feb, 10am-11am.

Week 1 (4 Jan) - Introduction.
Lecture 1 slides.

Required:

Zahnle et al. 2007.

Optional reading:

Chapter 13 of Schubert et al. 2001.

Chapter 3 of "Fundamentals of Geobiology". (Section 3.8 only).

Week 2 (11 Jan) - Jeans escape, hydrodynamic escape.
Lecture 2 slides.

Homework 1

Required reading:

Chapter 8.7.1. ("Basic concepts") of Pierrehumbert 2010. Note that you are not required to read Chapter 8.7.2, which is included in the pdf.

Watson et al. 1981. Note that you are not expected to derive all the equations.

Optional reading:

Catling & Zahnle 2009

Week 3 (18 Jan) - Diffusion-limited escape, runaway greenhouse, introduction to the long-term water cycle.
Lecture 3 slides.

Homework 2

Required reading:

Forget and Leconte 2014, "Possible climates of terrestrial exoplanets." Note that you are not required to read part 3 (on rotation).

Hamano et al., Nature, 2013.

Optional reading:

Karato, Treatise on Geophysics chapter, 2014. Sections 9.05.1, 9.05.5, and 9.05.6 are most relevant to the course.

Week 4 (25 Jan) - Long-term water cycle, continued.
Lecture 4 slides.

Homework 3

Required reading:

Walker et al. 1981.

Optional reading:

Parai and Mukhopadhyay 2012.


Week 5 (2 Feb) - Carbon cycle and Earth-climate stabilization.
Lecture 5 slides.

Homework 4

Required reading:

Maher 2010. A key paper marking the shift from thinking about Earth climate stability as mediated directly by changes in temperature to the current focus on indirect hydrological control. Note that the units on the x axis in Figure 1 should be 'yr', not 'yr^{-1}'.

Optional reading:

Edmond and Huh 2003. This paper, known as the "Summa Contra BLAG" manuscript, circulated for six years before being published. It cogently summarizes the evidence against the carbonate-silicate feedback described in lecture.

Ridgwell and Zeebe 2005. Note that section 4 is not needed for this course.


Week 6 (7 Feb) - Carbon cycle and Earth-climate stabilization, continued.
Lecture 6 slides.

Homework 5

Required reading:

Bowen 2013. Section 2 and Section 5 are not required for this course. An opinionated review of the ''organic carbon'' side to the story of the best-preserved hyperthermal in Earth history, the PETM.

Maher and Chamberlain 2014. This paper was covered in lecture on 7 Feb, so is included here as a refresher.
Maher and Chamberlain 2014 (SI). The Supplementary Information is not required reading, but gives the derivation of the equations in the main text.

Optional reading:

Galy et al. 2015. A neat compilation of present-day terrestrial particulate organic matter deposition rates, plus informed speculation as the response of these rates to increased tectonic uplift.


Week 7 (15 Feb) - Coevolution of Earth and life, Precambrian to Phanerozoic.
Lecture 7 slides.

Homework 6

Required reading:

Rothman 2003. This paper makes use of phase plane terminology. As a refresher, you may wish to refer to chapters 5.0 - 6.1 of the Strogatz textbook, 'Nonlinear dynamics and chaos', which is available online through lib.uchicago.edu

Optional reading:
Butterfield, 2007.

Beerling and Butterfield, 2012.

Week 8 (22 Feb) - Climate stabilization on Early Mars.
Lecture 8 slides.

Required reading:

Jakosky and Phillips, 2001.

Optional reading:
Grotzinger et al., 2014.

Wordsworth et al., 2015.

Week 9 (29 Feb) - (in Wieboldt 310C) - Numerical models.
Loscar option 2 (for educational use only). Tziperman's biogeochemical ocean model.

Lecture 9 handout.

No homework this week.

Reading to support the work in class:

Zeebe et al., 2009. (required)

Tziperman et al., 2011. (optional)



Week 10 (7 March) - (back in Hinds 451) - Ice-covered oceans.

Lecture 10 slides.

Homework 7.

Required reading:

Gaidos et al. 1999. Gaidos' fairly pessimistic conclusions are slightly moderated for Europa by the possibility of subducted oxidants, but hold with full force for oceans beneath geologically ancient ice shells (e.g. Callisto, Mimas).