Problem Session 3 [9/30/96]

You should now be ready to calculate the photodissociation rate coefficients we need for the course, using the direct beam flux as an approximation of the actinic flux. Since this should be relatively simple and we need to catch up, Problem 3 is being assigned on Monday, 9/30 and we would like you to complete it by the next Monday, 10/7.

• The first step is to visit the class webpage and view/capture the list of reactions that you will be using to develop your model for this course. This is given under -Other Course Information:- in -Chemical reactions needed for the class-. I will include all the sigma's [absorption coeficients] that you will need for this set of reactions. Lori will provide the Quantum Yield values for O(1D) and O(3P) formation from O3 photolysis, and I will provide the Quantum Yield values for HCHO photolysis later in the course.

Neither of the Quantum Yield values is needed for the next 2 problem sets.

• Pick up the data file, sigma1.dat either from the webpage or from the anonymous ftp site at ftp.gfdl.gov, This will be a formatted file [i3,6e10.3 ] of the form:

• Calculate jo2(Z), jo3(Z) [this is for either O(1D) or O(3P) production], jh202(Z), jhno3(Z), and jno2(Z) and either plot the photodissociation rate coeficients vs. Z or present a table. You will need to make a log plot of the photodissociation rate coeficients. Lori and I would prefer to look at plots, but we will check tables if you can't make plots.

These photodissociation rate coeficients, along with the reaction rate coeficients given in -Chemical reactions needed for the class- will next be used to calculate the ozone profile in the stratosphere for Problem Session 4.