Physics/Ocean 4520/5520 A Introduction to Atmospheric Science

Ian Folkins, Dept. of Physics and Atmospheric Science, Ian.Folkins"at"dal.ca, room 131, Dunn Building, 902-494-1292

Grading:

Two quizzes (30 percent), Assignments (20 percent), and final exam (50 percent). The number to letter conversion is A+(90.0-100), A(85.0-90.0), A-(80.0-85.0), B+(77.0-80.0), B(73.0-77.0), B-(70.0-73.0), C+(65.0-70.0), C(60.0-65.0), C-(55.0-60.0), D(50.0-55.0), F(below 50.0). For graduate students, the weighting is quizzes (30 percent), assignments (15 percent), project (10 percent), and final exam (45 percent). The conversion to a letter grade is the same as for undergraduates, except anything below 70 is an F. (see FGS calendar for implications on programme continuation). The final exam will be 3 hours and occur during the official examination period.

Textbook:

Atmospheric Science. An Introductory Survey, Wallace and Hobbs. Second Edition.

Syllabus:

We will cover Chapters 1 - 4, and 10 from the text, plus supplementary material from the class web page and class notes.

Pandemic H1N1 Influenza Advisory in relation to Academic Continuity

In the event of an escalation of the pandemic H1N1 influenza virus, the University may need to authorize Academic Units to change elements of class schedules and/or evaluation plans as outlined in course syllabi. Any change is intended to support the primary goal of reducing the risk of spreading a pandemic influenza among students, faculty and staff. Although it is difficult to predict the severity of the pandemic, the University is committed to minimizing the impact on student's academic progress. Therefore, every effort will be made to provide students with options for continued learning and for continued fair evaluations. Changes may include but are not limited to: - Adjustments to course assignments; - Changes to the dates of exams; - Arrangements for alternative evaluations for students affected by H1N1 influenza virus; - Adjustments to work terms; - Modification of marks awarded for participation; - Adjustments to attendance policies. Any alternative plan made in individual courses may be superseded by University-wide or Government measures to reduce the spread of the pandemic H1N1 influenza virus. We will continue to seek input from you and we will keep you informed as we proceed into the 2009/10 academic term. Should you have immediate questions or suggestions please contact Susan Spence Wach, Chair, Academic Continuity Planning Group,

Great Reference: Encyclopedia of the Atmospheric Sciences

This 6 volume encyclopedia is in the reference room of the library. The call number is REF QC 854 E735 2003. You can find a clear description of virtually anything there. Please drop by and check it out sometime. Wikipedia is also quite good on the atmosphere, e.g. the section on the Ice Ages.

Previous Test Questions

This is just to give you a flavour of the kind of questions I ask. Some of this material has not been covered.

Formula Sheet

Some of the formulas here have not yet been discussed in class, so you would not be responsible for.

SkewT- lnP Plot

Quiz Dates

Quiz 1: October 20 (class 12)

Quiz 2: November 17 (class 20)

Exam Date: Tuesday December 15, 10:00 am, 221C

Material:

In general, the quantitative questions will be similar to what has been given in the assignments, the tests, and tests from previous years.

A printout of the formula sheet and skewT-lnp plots will be provided. You are permitted a calculator but no other materials.

Required material for Quiz 1

As of October 15, I have covered most of the text up to page 78. The emphasis will be on the class notes, assignments, and web pages (i.e. Supplemental Material for Chapters 1, 2, and 3).

Required Material for Quiz 2

Quiz 2 will be on water vapor in the atmosphere (the various water vapor variables and their inter-relationships, skew-T plots, flow over a mountain, the des/dT derivation, es(T) curves, ice, stratocumulus clouds, the MALR, latent heats, EQPT, application to cloud height, moist static energy), buoyancy frequency, and what we have done in class up till and including Nov 12 on energy balance models, radiation, and the greenhouse effect. Note that some of this material was covered in the last 1-2 classes before quiz 1. In terms of Supplemental Material for Chapter 4, you are responsible for the sections up to and including the Mysterious Factor of 4 in S0/4. You are not responsible for Supplemental Material from other Chapters. From the text, you are responsible for Sections 3.4.4, 3.5.1 (except wet bulb), 3.5.2, 3.5.3, 3.5.4, 3.5.5, 3.5.6, 3.5.7, 3.6, and 3.7.3. Nothing directly from Chapter 4, though you may want to read parts of this Chapter for your own benefit.

Required material for the Exam

Everything required for Quiz 1 and Quiz 2, and all lecture notes since then. From Chapter 4 of the text, you are responsible for: 4.1, 4.3, 4.5.5, and 4.6. From Chapter 10, we did 10.1 (but not Fig 10.4 or 10.7 or 10.10). We also discussed Fig 10.31, 10.35, 10.36, the sections of 10.3 related to radiative forcings and feedbacks, and 10.4 on Global Sea Level Rise. I have gone through the web pages and made notes of the sections you are not responsible for. Everything else is required. The Trenberth paper is also required reading.

Answers: Quiz 2

(1) w, PT, fv, q, dse conserved.

(2) Main thing was to get constant value of dT/dz at dry value up to the LCL, sudden decrease in dT/dz at LCL, and slow convergence to dry value in upper troposphere.

(3) Hard for overnight surface temperatures to go below daytime Td since consensation as T < Td is a heat source, slows down T decrease due to radiative cooling.

(4) Can use to calculate equivalent potential temperature, and top outflow altitude near height at which EQPT of parcel coming up from the surface equals PT of background atmosphere.

(5) Mostly no problems, except w constant during descent in (viii) and equal to saturated value at 500 hPa from (v).

(6) Mostly no problems. Invoke conservation of PT in (iv) to find temperature at the surface, to get es.

(7) (i) Solar flux at earth = (Power of Sun)/(area of sphere with radius Re). As the distance Re of the earth from the sun increases the output power of the sun gets distributed over a large area, and the solar flux goes down. Same type of question as how much warmth do you get r distance away from 100 W light bulb. (ii) Done in the notes. (iii) recalculate the solar flux as in (i) and find the new TE using same procedure as in (ii).