in air pressure
air rises, it leaves behind an area of lower pressure, because the
upward- moving air is not pressing down so hard on the surface.
Areas of high pressure are formed where air is sinking back down,
and so pushing down harder. >>
A diagram shows differences in air pressure.
are many areas of high and low pressure above the Earth's surface
due to uneven surface heating. Air moves from areas of high pressure
to low pressure, forming winds. As a result, the greater the difference
between the high pressure and low pressure areas is, the higher
the wind speed is.
is different all over the world. Lows are areas of low pressure
with the lowest pressure at the center. Highs are areas of high
pressure with the highest pressure at the center. The way these
move from day to day causes the changes in the weather. Lows usually
bring wet, cloudy weather. Highs bring sunnier,dry weather.