Global Warming, Earth Orientation...

[JPreisig@AOL.COM]

Hmmmmmm,



       This is from:     jpreisig@aol.com     .



       Hello Radsafers,



            I guess there was another burst of chatter about global warming 

lately

       here on RADSAFE.  RADSAFE archives contain much of our previous

       discussion on this topic.



            A few weeks back, I saw a news item on YAHOO suggesting that

       some Pacific Islands are seeing elevated ocean levels recently.  I'm 

       sorry, I don't have a link for this item.  I guess one could blame the

       elevated ocean levels on global warming.



            As I said before, some of the global warming may be due to

       human activities.



            I also stated that some of this global warming may be due to

       geophysical causes, namely the superposition of the Earth's 

       annual wobble (a 12 month wobble) and the Chandler Wobble (a

       14 month wobble or 433 day period wobble).  These two wobble

       frequencies produce sum and difference frequencies (see your

       undergrad mechanics book, i.e. Marion) which affect the overall

       Earth Orientation.  This superposition of wobbles affects the angle at

       which the Earth's spin axis and geometric

       axis are directed towards the sun.  Wobble amplitude maxima occurred

       roughly in 1910, 1954 and 1998.  An increase in wobble amplitude

       occurred from about 1976 to about 1998.  This may explain some of the

       recently observed global warming.  In 1998, summer may have been a

       bit warmer and winter may have been a bit colder.  



            I would suggest that the warmer summer and colder winter might

       negate any overall thermal effect, except for the fact that the Earth

       is not a symmetric object --- the Earth is an oblate spheroid with a

       superimposed (smaller) pear shape.  Much of this wobble information

       is contained in books by Munk and MacDonald and Lambeck (2 books)

       and Stacey.



            Anyway, I guess reactor power would help us with global warming,

       while building up our spent fuel supplies.  We also are aware what

       happens when we depend too much on coal for power.



            Seems like we have to keep an eye on what is actually happening

       with global warming.  For now, enjoy all those Cicadas.



            Take Care.                      Joseph R. Preisig,

                                                  M.S., Health Physics

                                                  Ph.D., Geophysics