Day 011 - 12 Jul 94 - Page 40


     
     1        emitted by cattle?
              A.  About 80 per cent.
     2
         Q.   80 per cent of 80 million tonnes.
     3        A.   Yes.  I would have to say this is an estimate because
              in some countries the records and the number of cattle are
     4        not very accurate, and if one looks at, for example, the
              World Meteorological Organisation report on global
     5        warning, an error of something like 30 per cent is put on
              the total amount of methane emitted in this way.  So, when
     6        one talks about 80 million, it could go up to 100; it
              could go down to about 50.  It depends how you do the
     7        errors on it.  This is again because very large countries
              like India do not necessarily have very good statistics on
     8        the total number of animals which are actually around at
              any one time.
     9
         Q.   If the contribution to the total global methane content of
    10        the atmosphere annually of animals is only 80 out of 550
              million metric tonnes, what are the other principle
    11        contributors to that level of methane?
              A.   Landfill sites, leaks from the natural gas pipelines
    12        which in somewhere like the United Kingdom actually
              dominate; rice production which in the Far East is an
    13        enormous contribution (in fact it is actually larger than
              the total amount due to enteric fermentation).
    14
         MR. JUSTICE BELL:  Can you just put a figure on rice
    15        production?
              A.   Yes, it is about 100 to 110 million tonnes compared
    16        to the 80 million which has been estimated for the
              fermentation processes.
    17
         MR. RAMPTON:  By 'rice production' you mean paddy fields?
    18        A.   From paddy fields.
 
    19   Q.   If paddy fields emit methane they are man-made, of course,
              and they are made so that people can eat rice.  Now, what
    20        about natural conditions of a similar kind such as swamps,
              bogs, marshes, and so on?
    21        A.  They are also of the order of 100 million because
              there are still some very large, natural bogs.  In fact,
    22        the colloquial name of methane at one time was marsh gas
              which indicated it was actually produced from marshes and
    23        bogs.
 
    24   Q.   Is that what produces the wil'o'the wisp?
              A.   Yes.
    25
         Q.   Does all that 550 million tonnes of methane actually get 
    26        absorbed into the atmosphere, or not? 
              A.   No, the majority of the methane which is emitted into 
    27        the atmosphere is destroyed by the so-called free radical
              reactions which again primarily involves hydroxyl. The
    28        estimate of the current increase in the total methane in
              the atmosphere per annum is of the order of 40 million
    29        tonnes which is the balance, if you like, between a large
              amount of production and a large amount of destruction.
    30
         Q.   So, the environment manages to cope, out of the 550

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