Why earth's air moves faster than earth itself

A chance to avoid gobbledygook

Dear Matt: I posed this question to a TV meteorologist (not in California), and all I got was a lot of gobbledygook that didn’t answer my question, which follows. Relative to the sun, our earth rotates from the west to the east. Our weather also moves from the west to the east. In other words, our atmosphere seems to rotate at a rate slightly faster than our terresphere. Is there a scientific explanation for this phenomenon? — Vic Lavetter, La Mesa

Gobbledygook is M.A.’s daily fare. My hands are really tied if I can’t throw a little of it around...but if you insist. Actually, there’s a leap of logic in your question that I’m not sure I can make, but I think I get your basic west-east drift. Weather is just a very low-altitude element of our atmosphere as a whole, not something separate from it. Gravity binds the atmosphere’s gas molecules to Earth, so it rotates with the planet as a package deal. If the atmosphere moved at some rate different from the rotational speed of the planet, your hat would blow off every time you walked out your door.

(Gobbledygook alert! Young children, pregnant women, and those with a chronic ringing in the ears should be attended by a competent adult to act as spotter while reading this section, which may contain some unavoidable jargon. No lab animals were sacrificed to test this material.) Weather movement (that is, wind) is governed by zones of unequal heating of Earth’s surface. Hotter and cooler areas create areas of high and low air pressure. Air moves from high to low pressure. At this point, we’ll skip a whole bunch of technical whereas-es and therefores and go straight to the fact that our winds basically circulate in six zones according to the broad pattern of heating and cooling of the Earth. Winds move east to west around the poles and the equator and west to east in a band between the two. So this question of “weather moving west to east” applies only to certain latitudes on the globe. And because there’s friction at the point where atmosphere and terresphere meet, if anything, low-level winds are slowed down a bit. But all this still takes place within the atmospheric envelope itself, stuck by gravity to the globe. Still baffled, Vic? I’ll bet you are. Some things just demand gobbledygook. This may be one of them.

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