Lower Atmosphere

Basics

1. Extension and composition

Worksheet 1: Air and temperature

The experiments below (marked E) will give you an idea of the dynamics of different regions of the atmosphere. They can be regarded as a model of the vertical structure of the troposphere up to the stratosphere.  The different tasks (T) will help you understand your experimental results.

You need these things for the experiments:

1 - 2 350mL some 1 1 1 some 1

incense sticks ice (crushed ice) salt (NaCl) play dough glass tube (1 m long, between 2.5 and 3 cm in diameter) retort stand and clamp plastic bag (1 - 2 L in volume) binding wire lighter or matches hair dryer aluminium foil or watch glass

• E1

Light an incense stick. Make sure the incense stick is in a draft free environment.

• T1

In which direction does the plume of smoke go? 

• T2

How does the plume of smoke change as it moves away from the incense stick into the air?

• T3

Look at the chapter: "Lower atmosphere - Basics  - 1. Troposphere  - vertical".
Which phenomenon does the incense smoke demonstrate?

 

• E2

Cut a 2-3 cm long piece of incense stick. Put this into some play dough so that it stands upright. Fix the glass tube onto the stand. Light the incense stick. Put the glass tube over it.  Make sure there is a little air gap between the tube and the retort stand base or the table. Observe the smoke. (It is useful to look upwards along the tube).

• T4

How does the smoke in the tube behave?

 

•  E2a

Fill a plastic bag a third full with crushed ice. Add some salt to it and seal the bag. Use a piece of binding wire to fix the ice filled bag half way up the glass tube.  Use more wire so that the ice surrounds the middle part of the tube and so that at least half of the tube is covered.  Cap the top of the tube with aluminium foil or a watch glass.  Prepare an incense stick in the same way as in the previous experiment.  Heat the upper part of the tube with the hair dryer so that it's too hot to touch.  Then heat the bottom part of the tube with the hair dryer.  Light the prepared incense stick.  Take the aluminium foil off the top of the tube. Put the incense stick into the glass tube as in the experiment before. Observe the smoke.

 

• T5

How does the smoke in the glass tube behave now?

• T6

The experiment is a model of our atmosphere. Which parts of our atmosphere do the letters a, b and c in the picture represent?

 

The graph shows different temperature profiles in the atmosphere for three regions and two seasons.

• T7

There is only one temperature profile for the tropics.  Is this enough?

 

Substances entering the air can be transported upwards in the atmosphere, just like the smoke in our experiments.  The "cold trap" acts as a barrier to this upwards movement.  Only tiny amounts of gases can pass through into the atmosphere above.

• T8

Some gases do get into the upper atmosphere.  Use the graph to help you work out where and when this is most likely.

 

About this page:

authors: M. Seesing and M. Tausch - Universität Duisburg-Essen, Duisburg, Germany
last update: 2004-05-13