RE: Effects of magnetosphere loss

["Augustus T. White" <augwhite@neosoft.com>]

On Saturday, August 22, 1998 1:53 PM, Jim Choate [SMTP:ravage@ssz.com] 
wrote:
>
>  The Van Allen Belt is not part of the atmospher strictly speaking. It is 
the
>  interface between the solar magnetosphere and the Earths. Even if the 
Earth
>  didn't have an atmosphere it would have a magnetosphere (ie Van Allen 
Belt).
>  The disruption to the belt would not come from the loss of ejected gases 
but
>  rather the shift in the Earths center of gravity caused by the impact 
(and I
>  assure you a 100mi. dia. crater will make the Earth wobble and ring for
>  quite a while) and the em interactions of the impact (Q: has anyone
>  calculated the EMP from such an impact?).

The impact should have been energetic enough to create an ejected plasma of 
its own -- a sort of solar flare in reverse.  Should have done wonders for 
particle recruitment!

>  Actualy the Van Allen Belt can be measured in the geologic record by
>  measuring the magnetic stripes in the sea floor upwellings. These are 
1-to-1
>  correllated since they come from the same thing - the Earths magnetic 
field.
>  Pick stripes of a given polarity and correlate the changes in 
magenetization
>  along that stripe in relation to other markers. One marker might be to
>  compare it to both measurements and models of the long-term solar 
output.

I'm not sure I follow.  The stripes give us polarity and general direction. 
 Can you get quantitative information (field strength) as well?  Does this 
tell us anything about the state of the magnetosphere?

>  Seems to me that if there was an increased level of solar radiation (and 
I
>  don't mean the UV that the ozone layer blocks) the consequences would be
>  plastered all over both the geophysical and biological records. One 
would
>  simply have to look at the effects of increased radiation on long-lived
>  chemical and bio-chemical systems today and extrapolate backward looking 
for
>  those same tale-tales. It might be as simple as looking at the ratios of
>  isotopes in trapped air samples in the Antarctic and comparing them to 
the
>  mid-ocean upwellings mag stripes.

This may turn out to be a very complex process, all of which may add up to 
little net result.  For example, any loss of magnetospheric blocking of 
charged particles may be offset by physical blocking by dust in the lower 
atmosphere during KT+0 to KT+3 (to put a speculative number on it). 
  Magnetic storm disruption of the magnetosphere is over in a few days. 
 What reason do we have to think this would be a longer term process? 
 Changing the *shape* of the Van Allen belts should have little effect on 
their ability to redirect charged particles, so that the vibrations due to 
the impact would not be reflected in any long-term inrease in high energy 
particles reaching the surface.  Finally, I'm not to sure how seriously to 
take my solar-flare-in-reverse idea above, but it does seem likely that the 
impact would create ejected high energy ions which could be recruited by 
the magnetosphere.

>  Most mutations are neutral and don't effect the viability of the species 
or
>  the individual. Next comes mutations that are harmful and finaly, and 
least
>  likely, are mutations that are beneficial. While this is interesting it 
is
>  probably pointless. Even if a given species were to exhibit a beneficial
>  mutation the chances of the other ecologicaly linked species to have 
mutations
>  that allowed them to survive would nullify the beneficial events. 
However
>  powerful the positive forces might be they would not be sufficient to
>  compensate for the ecological damage on a broad front.

If this were true, there could never be a beneficial mutation.  Recall we 
are, in any case, dealing with a highly disrupted ecosystem undergoing 
rapid succession.  If there were ever a time when a mutation could find a 
new niche, this was it.

  --Toby White