Weather wise question?

Question

I was reading about global wind patterns that produce area of high pressure over the poles and area of low pressure over the equator. So if high pressure is conducive to good weather and low pressure for bad.This seems to be the opposite.

Answer 1

It is not the wind that creates high and low pressures; it is the rising or the sinking of the air. That can happen from different reasons; heat or mountains faces.

But generally speaking the equator is hot and the air rises, thus giving place to low pressures. The poles are cold; the air sinks thus giving place to high pressures.

Basically, the air rising at the equator would then move toward the poles on the top, and from the poles to the equator at the base, or earth surface.

That's what would happen if it wasn't that ... the earth spins. This creates to so-called Coriolis effect and the air moving in any direction on the northern hemisphere is diverted toward the right. As a result, the air from the equator never reaches the poles but sinks in a belt of high pressure around the latitude 30. Likewise, the cold air from the poles don't reach much more than latitude 60 and form a belt of low pressure there. This is also due to the front between cold and dry polar air, and humid and mild temperate air. On the top of that front moves the jet streams that tend to move the low pressures to the east.

Those lows at the 60s are called frontal lows. On the equator, they are called convective lows ... well, that is the big picture; weather can be detailled very much depending the region, etc.

I hope it helps.

Answer 2

No it doesn't.  High pressure areas means the air is sinking.  This creates stable conditions and it is very tough to get precipitation to form under areas of high pressures.  

The said is the opposite for low pressures.  Air is rising here and the airmass is more unstable which leads to the formation of clouds and precipitation.  If you look there is more in the way of activity around the equator than the Poles.

Answer 3

Subsidence or a downward vertical motion is associated with high pressure.   It is also drier because of this motion and can hold less water vapor.   At the equator the air rises is thinner and thus able to hold more water vapor.  The combination of lift and moisture produce clouds,  which produce rain and thunderstorms.   High pressure is colder and denser and does not allow for much moisture or weather.