Day 011 - 12 Jul 94 - Page 13

     
     1        as well as chemistry?
              A.  It does.
     2
         Q.   Did you do a post graduate qualification in physics?
     3        A.  No, my post graduate qualification was in
              Spectroscopy.  It was actually carried out within the
     4        Department of Chemistry at the University of Sheffield.
 
     5   Q.   Are you, as well as being a bachelor of science, a doctor
              of philosophy, a fellow of the Institute of Physics?
     6        A.  I am.
 
     7   Q.   Is that something you just get given, or do you have to
              qualify for it?
     8        A.  If you do not have a physics degree, it is necessary
              to submit a collection of publications to show that as a
     9        result of post graduate experience you are, in fact,
              qualified to become a fellow of the Institute of Physics.
    10        So what happens is you submit a set of publications to the
              Institute of Physics that go to external referees.  On the
         basis of that you can become a fellow, which is what
              I did.
    12
         Q.   Is one of your specialities at least -- forgive my loose
    13        language from time to time -- the stratosphere?
              A.  It is.
    14
         Q.   Can you tell us, please, a little bit about the way in
    15        which the earth's atmosphere is constructed?
              A.  Yes.  The earth's atmosphere is constructed in such a
    16        way that as one goes up from the surface of the earth, the
              pressure drops.  This is well known to anybody who has
    17        climbed up a mountain, particularly the Alps.
 
    18        The main heating of the earth comes from the sun.  The
              sunlight can pass to a large measure unhindered through
    19        the atmosphere, certainly in the visible region; it heats
              up the surface of the earth, which acts like the soil in a
    20        greenhouse, and it re-emits light; but the light that is
              re-emitted is what we feel as heat and is usually referred
         to as infra red radiation.
 
    22        The heat, or the infra red, can then be absorbed by some
              of the gases in the atmosphere, and the main gases which
    23        are minority gases in the atmosphere responsible for the
              re-absorbtion are carbon dioxide and water vapour.
    24
              Some of the heat or infra red comes back to the earth.  In
    25        fact, it is what keeps us warm.  Some, in fact, is
              radiated into space.  That means that the greenhouse 
    26        effect is a naturally occurring phenomenon which allows 
              life on the planet to exist. 
    27
              As one goes up in the lower part of the atmosphere which
    28        is called the troposphere, the temperature in fact drops
              and reaches a minimum at a height of about 14 kilometers,
    29        which is known as the tropopause.  Above this height the
              temperature starts to rise again.  This is because some of
    30        the light from the sun is absorbed by oxygen and by ozone
              and causes a heating in the part of the atmosphere known