Fog!                                                           11/7

     1.  What happens to the 'cut-off low' after it  has separated from the major circulation?
              As with all upper-level lows, air from beneath will rise into the region with low pressure.  Since there is no longer
                 upper-level divergence, this will raise the pressure and the "cut-off' low will be no more. 

    2.  Are high pressure regions the cause of the transition from zonal flow to meridional flow in the upper-air
         pattern?
              This is a chicken-egg sort of question, "Does a meridional flow pattern cause high pressure ridges, or do high
                 pressure ridges cause a meridional flow pattern?"  The intimate relationship between the two makes it virtually
                 impossible to say that one is a cause and the other an effect.  The basic pattern is inherently unstable and continually
                 changing.  The fundamental causes of the pattern are continually changing which makes the pattern unstable.  The
                 fundamental cause of air circulation is the uneven heating of the earth's surface by the sun.  The variables that lead
                 to the instability include the seasonal changes in the solar heating at every point on the earth's surface, the daily
                 changes in the rate of heating, the changes in the surface temperature of the ocean due to such irregular cycles as
                 ENSO and other similar, but more subtle and less known cycles.  Even possible are small, but real changes in the
                 solar output. 

    3.  Are the regions in between the lows in the Rossby wave pattern, highs?
              As Lehi once said, "it must needs be, that there is an opposition in all things."  The
                 lows are lows, only because they are low with respect to something else, namely the
                 interlobe highs, or high pressure ridges.

    4.  Could you define cyclogenesis?
              Cyclogenesis refers to the formation or the intensification of a cyclone (low-pressure region)
                 which can happen only if there is a region of divergence aloft above the strengthening cyclone. 

    5.  Why do the upper-level winds, after curving to the right as they pass above a mountain range, curve back to
         the left to their original direction of flow?
              After the flow passes over a mountain range it reverts to a thicker layer (thicker troposphere) which reduces the flow
                 speed, which in turn reduces the Coriolis force on the wind, leading to its curving back to the left, to acheive
                 equilibrium, in its original direction.

                         6.  What is diffluence?  Confluence?
                              These terms are better known in the context of stream flow.  When two rivers combine to form a single river that combining
                                     and the point at which it occurs are both known by the term confluence.  Similarly, merging streams of air constitute a
                                     confluence.  Rivers also exhibit diffluence.  When a river splits to flow about the two sides of an island, that splitting could be
                                     referred to by the term diffluence.  Similarly, a splitting stream of air constitutes a diffluence.  (Please click on each of the terms
                                     to recall the graphic that illustrates the process.)