Fog!                                               12/3

     1.  Which volcano is most active and which has caused the most fatalities.
             That depends on how you define "most active."  Kilauea, the southeasternmost volcano on the big island of Hawaii
                is often regarded as the world's most active volcano.  It has erupted 34 times since 1952, including the current eruption
                which began on January 3, 1983, and has yet to cease. (It has been continuously erupting for almost 26 years!)
                Kilauea's eruptions are expected and relatively non-violent, so it has caused but few fatalities.  Big, explosive and
                unexpected eruptions have killed the most victims.  The fatality numbers associated with such eruptions are rather
                uncertain, but in historic times the most lethal eruption was that of Tambora, Indonesia, in 1815 which is estimated to
                have caused 92 000 fatalities.  Vesuvius in Italy has killed many victims in each of several known eruptions
                (including that which destroyed Pompeii and Herculaneum in 79 A.D. with about 2000 fatalities).  It poses the greatest
                known volcanic threat to life at present since the city of Naples, with a current population of about 4.4 million in its
                metropolitan area, would be almost entirely obliterated if Vesuvius were to erupt with the violence known to have
                occurred in its 3580 BC eruption.

    2.  Is volcanic activity considered to be a positive or negative climatic feedback?
             Neither.  It causes climatic cooling, but since it is triggered independently, with no dependence on climatic
                conditions, it is not a feedback mechanism.  To be a feedback mechanism such a mechanism must be climate
                caused.

    3.  Is the fact that in recent days the local temperatures have been running about 10°F above normal related to
         global warming?
             No, it has been abnormally warm because of a persistent high pressure ridge over us which has caused the upper-
                level flow to have blown in air from far to our south.  Just the opposite has occurred in the eastern US where a
                persistent trough has cause the upper-level flow to have blown in air from far to the north, causing much colder
                than normal temperatures.  The effects of global warming are, so far, much smaller than this.  Perhaps the
                temperatures have been 1°F or 2°F warmer, both here and in the East, than they would have been in the absence
                of such warming.

    4.  Could Utah ever have been a spot for volcanic activity?
                Yes, in particular there are four areas in Utah which exhibit both lava beds and volcanic cones.  The nearest is the
                so-called Black Rock Desert volcanic field near Fillmore, about 100 miles south-southwest of Provo, which produced
                a lava flow only 660 years ago.

    5.  Why is Antarctica warming so much if no one lives there?  Doesn't this suggest that global warming is not
         the effect of man?
                When the greenhouse gases thought to be the cause of global warming are emitted, they rapidly spread out almost
                uniformly in the atmosphere.  The associated warming is therefore not localized around the sources of those
                greenhouse gases.  All locations on the globe are affected.  Mathematical models of the atmosphere predict that the
                greatest change in temperature will occur at high latitudes (in the Arctic and Antarctic) just as has been observed.

    6.  Couldn't we just be in the end of the Pleistocene ice age and that is the cause of the current warming?
                That possibility cannot be entirely ruled out, but the very rapid, current rate of warming is much faster than most of
            `   the short-term warming (and cooling) maxima which have been superposed on the very slow warming trend,
                suggesting that a new, different mechanism is driving the change.

    7.  How can we tell that the earth's orbit changes if it only changes every ~50 000 years.  Is that fast enough
         to observe?
                Yes, that is fast enough to easily observe.  Remember that ~50 000 years represents the period of a full cycle of change. 
                The changes occur continuously.  The change we call "precession" has the shortest of the cyclic periods, 26 000 years.
                That change is fast enough that it was known to the ancient Greeks who inferred its existence many centuries before
                the invention of the telescope.