Science A-30: The Atmosphere

Syllabus: Spring 2008
Prof. Steven C. Wofsy, Pierce Hall 110D; tel. 495-4566;


Tu, Th 10:00-11:30 AM in Science Center E; sections (1 hr per week) are required.


Wednesday 10-11am, Geological Museum 418 (Head TF: Ben Lee)
Wednesday 12-1pm, Geological Musemum Shaler room 413 (TF: Eric Kort)
Tuesday 1-2pm, Geological Museum Daly room 105 (TF: Elizabeth Hammond Pyle)
Tuesday 4-5pm, Pierce Hall 100F (TF: Moeko Yoshitomi)

Regular, assigned sections begin the week of 12 Feb. Attendance is mandatory

Teaching Staff

Course materials:

Recomended Textbook:
The Atmospheric Environment
by M. B. McElroy (Princeton, 2002). This book was conceived by Prof. McElroy during his development of Science A-30.

Source Book:
A collection of journal articles on the atmosphere and on atmospheric environmental issues is presented in an online sourcebook; it will be used extensively in the course discussions and to research topics for your term paper.

A-30 Companion Text: Chapters are on-line.

Course Overview

Science A-30 introduces students, typically not science concentrators, to the physics and biogeochemistry of the atmosphere. Atmospheric physics refers to weather (clouds, rain, winds) and climate (why deserts exist where they do, long term trends in temperature and precipitation). Ecosystems refer to the natural and managed assemblages of plants and animals on land and in the sea. The course material is presented at the level of the intuitive and willing non-scientist. Calculus is not used.

The course begins with study of the fundamental laws of physics and applies them to atmospheric phenomena. Lectures emphasize physical and chemical principles (pressure, Coriolis force, planetary and solar radiation, changes in atmospheric composition) and analysis of atmospheric data. Science issues such as global climate change, interactions between climate and ecosystems on land and in the sea, changes in land and sea ice, and trends in typical cyclones and hurricanes are examined in the second half of the course. We examine the rise of global CO2 and other greenhouse gases (e.g. CH4) in the atmosphere: why this has happened, and what are the implications.

Humans have major influence on the atmosphere, especially through combustion of fossil fuels, agricultural activities, and changes to the landscape. The associated modifications of atmospheric composition and climate may have far-reaching economic, social, and political implications. Students will use the knowledge they gain of basic physical principles to examine critically arguments on environmental questions, starting with assessment of the knowledge base and definition of the issues.

A goal is to enable students to understand and to distinguish between scientific fact and unproven hypotheses, to recognize quantitative and heuristic analyses, and to distinguish the scientific aspects of atmospheric environmental problems from economic, social, and political arguments. Because science has its own vocabulary, idioms, and logical paradigms, reading assignments have been developed to introduce students to primary sources in the scientific literature, providing the opportunity to evaluate observations and interpretations.

It is hoped that students obtain critical skills that will be life-long assets for scientific and policy literacy, invaluable to individuals entering public policy-oriented careers and to anyone intent on living as responsible world citizens in today's changing global environment.

Spring 2008 term paper topics:

  1. Polar Ice: Changes, feedbacks
  2. Climate in the Past (Paleoclimate) or Climate Cycles in the Geological Record Lessons for the future

Office consultations

Students are encouraged to meet personally with the faculty and/or teaching fellows. Teaching fellows have regular office hours that can be found on the Web page. Electronic mail is the best way to arrange for a consultation at other times or with Professor Wofsy, but a time may be arranged before or after class or by telephone call as well.

Lecture schedule

Science A-30, Spring 2008 (Due dates may change.)
  Note: Entries from the last presentation of the course (2007) are rolled into updated (2008) versions as the course progresses. The section on hurricanes will likely be replaced by new materials on polar ice.
Date Lecture Topics and Summaries Reading, Writing, 
and Exams
31 Jan


Roadmap of A-30 Parts I and II: (05 Feb. -- 06 March):
Structure, physical processes, dynamics of the atmosphere.

Reading: McElroy Chapter 1
                 Chapter 2 Lecture Notes
PS 0 distributed 1/31
05 Feb
07 Feb
Physical concepts: pressure, temperature, momentum (Lecture 2)
Structure of the atmosphere: pressure v. altitude (Barometric Law; Lect 3).

Online "Perfect Gas" Demo--manipulate T, P, V, N and observe!

Reading : McElroy Chapter 2
                  Chapter 3 Lecture Notes
PS 0 due 2/7
PS 1 distributed 2/7
12 Feb

14 Feb

Physical concepts continued: Buoyancy, Archimedes' Principle
Photo album and movie, 2006 "Blizzard" [powerpoint format]
Properties of water, decline of temperature with altitude, adiabatic lapse rate
Reading: McElroy Chapter 4
                  Chapter 4 Lecture Notes      
PS 1 due 2/14
PS 2 distributed 2/14
19 Feb
21 Feb
Vertical structure of the atmosphere, stability & buoyancy
Vertical atmospheric structure (continued): wet & dry convection
  • Animation: Wet and Dry Adiabat & Rainshadow

Roadmap:Concepts, development, and structure of the lectures:
I. Lectures 2-7, Atmospheric structure, basic physical processes.
II. Lectures 8-11, The atmosphere in motion: Weather and Climate
Reading: McElroy Chapter 5
                 McElroy Chapter 7
                 Chapter 5 Lecture Notes
PS 2 due 2/21
PS 3 distributed 2/21
26 Feb
28 Feb
Horizontal Motion of the Atmosphere : Coriolis force, angular momentum;
Discussion of evidence, hypothesis, and uncertainty concepts in science.

Horizontal Motion of the Atmosphere : Storms and Synoptic Weather Systems
Reading: McElroy Chapter 5
               McElroy Chapter 7
PS 3 due 2/28
PS 4 distributed 2/28
Critical Summary 1.1 due 2/28
04 Mar
06 Mar
Hadley and Walker Circulations, Jet stream
Animations Rotating Annulus  || Full disk 2007 || Cyclone 01 March 2008
Reading: McElroy Chapter 8
               Chapter 5 Lecture Notes
PS 4 due 3/6
PS 5 distributed 3/6
11 Mar
13 Mar
Atmospheric composition & changes over the "recent" past (2 lectures)
Atmospheric composition & changes over the "recent" past (2nd of 2 lectures)

We examine a key driver of global atmospheric change: human-induced changes in global atmospheric composition.

Reading: Chapter 5 Lecture Notes
PS 5 due 3/13

18 Mar

20 Mar
The cycle of CO2 on the earth: introduction, ocean chemistry and uptake, terrestrial uptake
View SST movie 1 and SST movie 2.
MIDTERM EXAM--MARCH 20, 10:00-11:30 AM;
Students may bring ONE TWO-SIDED PAGE of notes
Calculators required.

  • Chapter 8 Lecture Notes
  • McElroy Ch. 9 and 11 (1st half)
PS 6 distributed 3/20
25 Mar
27 Mar

01 Apr

03 Apr
The cycle of CO2 on the earth: introduction, ocean chemistry and uptake, terrestrial uptake
Introduction to Electromagnetic Radiation
Reading: McElroy Chapter 11 (2nd half)
Chapter 6 Lecture Notes
PS 6 due 4/3
PS 7 distributed 4/3
08 Apr

10 Apr
Energy budget and Temperature of a planet orbiting a star

Climate, "Greenhouse gases", Climate and "Feedbacks"
Reading: McElroy Chapter 10
Chapter 7 Lecture Notes
PS 7 due 4/10
PS 8 distributed 4/10
Critical Summary 1.2 due 4/10
15 Apr
17 Apr

Climate, "Greenhouse gases", Climate and "Feedbacks" (continued)
Read "Climate and Man", Part 1 and Part 2
PS 8 due 4/17
PS 9 posted online  4/17

22 Apr
24 Apr
Dr. Horii

29 Apr
Prof. Jacob
Arctic Climate: Sea Ice in the climate system: Outline of Lectures

Historical Overview:
Sea ice in the paleo, historical, and recent records
What is sea ice? How does sea ice form? Climate effects sea ice: heat, evaporation, hydrology of the boreal zone, brine rejection/thermohaline circulation.
Environmental and ecological effects of sea ice retreat: marine mammals, fisheries, mining and energy extraction, shipping and pollution
Reading: McElroy Chapter 19; Ch. 12
PS 9 distributed  4/24
29 Apr

01 May
Prof. Jacob
Is climate really changing? Can we attribute climate change to identifiable causes?
A discussion of scientific data assessment, causality, skepticism, and risk.
Reading: McElroy Chapters 19 & 20
Storm surges
PS 9 due 5/01
Reading period Final paper due on 14 May (at 5pm), the last day of reading period.  See the Writing Guide in the Source Book for more information on the assignment.  

Course requirements and Grading Determination:

Lecture: 1000 -- 1130, Tuesday & Thursday, Science Center Hall E

Lectures cover all aspects of the science of the atmosphere, including physical principles, history of measurements, current policies and events, demonstrations, examples, and discussion.

Weekly Problem Sets: 20%

The problem set questions will address basic concepts and skills taught in the course and prepare students for their sections and exams.  The lowest problem set grade will be dropped (grade will be based on 10 problem sets).  Answers to the questions will be available after the due date. 50% credit for late assignments.

Section Participation: 10%

In addition to discussing the assigned section problems,  sections will also integrate and understand lecture material, discuss aspects of problem-solving and quantitative analysis, and emphasize the important ideas in the course.  Section attendance and participation is reflected in this portion of the grade.

Writing Assignments:  25%
Critical Summary 1.1, & 1.2 (5%); Term Paper (20%)

Students prepare a term paper (5-6 pages, due at the end of reading period) by conducting in-depth analysis of a topic chosen from a list of topics related to Science A-30. A structured set of assignments leads up to, and is incorporated into, the term paper.  

See the web page on The Atmosphere: Writing for Science A-30 (also in your sourcebook) for more information about available topics, writing assignments and the term paper.

Midterm: 15%

Final Exam: 30%
This will be a comprehensive exam covering all lecture and section topics.  

Special Note: Collaboration

Students are encouraged to form study groups and to discuss Science A-30 concepts and materials with their fellow students. However, all submitted work must be carried out by the student submitting the work. Joint submissions of a collaborative product (problem set, written assignment, term paper), or use by one student of material authored by another, are not permitted.