Meteorology 465/565 The Middle Atmosphere

Take-home, Open-book Final Exam

assigned: 25 April 2003

due: 09 May 2003

You may use any information sources you wish, except each other. If you have any questions about the meaning of my questions, please contact me.

Stratospheric meridional circulation (30 points). Much of the last half of the course has been devoted to a description of the dynamics that transport air through the stratosphere from the tropics to the high latitudes. Please condense this discussion down to the most important concepts. You can use equations to help make your points. Please use no more than a few pages (about one type-written page).

Asymmetric springtime NH and SH ozone columns (10 points). We have talked about the greater wave activity in the Northern Hemisphere than the Southern Hemisphere and how that greater wave activity results in a greater downward mass flux in the Northern Hemisphere than the Southern Hemisphere. Can you explain the greater springtime ozone column in the Northern Hemisphere than in the Southern Hemisphere using the same concepts? Please explain the processes that support your answer.

Stratospheric heating by water vapor (20 points). In one of the problems, you determined the vertically resolved heating rate due to ozone and molecular oxygen. Like ozone, water vapor has ppm-level mixing ratios, so that we might suspect that water vapor has a significant role in the solar heating.

• Using the same calculation strategy that successfully determines the heating rate due to ozone, find the heating rate due to water vapor, as a function of altitude.
• How does the heating rate due to water vapor compare to the ozone and molecular oxygen heating rates?
• What differences between water vapor and ozone make their heating rates so different?

Replacing ozone lost in the Antarctic ozone hole (20 points). Suppose that you are at a party. Another guest says: “O.K, the Antarctic ozone hole is real. It needs fixed. But all we gotta do is make a bunch of ozone, load it onto airplanes, fly it into the stratosphere and let it go. That’ll do ‘er.” Let’s ignore the question about whether it is indeed possible to transport a large amount of ozone into the stratosphere.

• Please calculate the amount of energy that is required to make enough ozone to replace the ozone lost in the Antarctic ozone hole each year. Your answer should be in units of Joules and kW hours. Assume that 200 DU of ozone are destroyed, all in the lower stratosphere.
• How does this amount of energy per year compare to the typical US annual energy production?

Climate change and the stratosphere (20 points). How does stratospheric chemistry change if the troposphere (and tropical tropopause) warm while the lower stratosphere cools, which is a likely result of global warming? Are there any dynamical effects that you can think of?