Andrew Sarangan wrote in news:50f64be0-71fb-47d0-
:

Looking at the worldwide surface analysis chart, it looks like land
areas have far more pressure variations than oceans. However, I am not
sure if this is a real effect or simply an artifact of the fact that
there aren't many observation stations on the oceans. Any thoughts?


Both land masses and oceans spawn pressure systems. The north atlantic
is a good case in point, where the convergence of cold and warm air
masses spun into a giant mess by coriolis produces wicked lows that can
range as far down as 27.5 ( I've seen it this low in western europe)
Land masses are better at cooking up highs and I've seen it off the
opposite end of the scale in the eastern US at well over 31 inches. You
can also get this anywhere within spitting distance of Russia from one
of the famous "siberian highs"

BTW, when it gets that low or high at a teminal, ATC will only give you
estimates of the pressure, particularly with highs. Their equipment
doesn't go that far.


Bertie