Where Does Weather Come From

[R. S. Martin]

I'm not sure how to say this but our "weather" always seems to come from some distant place too far away for me to go check it out. For example, right now there's a forecast that a moisture laden low pressure system is coming from Texas. I know some of you live in Texas.

 

QUESTION: Did you Texans see this weather system develop in your backyard or across the street? Or what does it mean when Environment Canada tells me that some weather system or other is coming from Texas or the prairies or the Arctic? How does a gust of wind develop into something that is called a system that travels across the continent? 

 

The thing is, they're often right so I'm thinking there's got to be something to it but where or how does weather originate?

 

Easy Answer: God did it.

 

I no longer accept that answer because I sort of know there's a natural explanation.

[R. S. Martin]

This is a serious question. Does none of you scientists know how weather systems develop?

 

Maybe the rest of you learned it in high school but I was taken out of school at age 14 and missed high school.

 

In a Christian philosophy book I read an argument about a weather system starting because a butterfly in Africa fluttered its wings but that seemed ridiculous, not to mention suspect since it came from evangelicals James Moreland and William Lane Craig. 

 

So I'd be interested to know a scientific explanation in layman's terms, if anyone cares to respond.

 

Thanks.

[RogueScholar]

In highly simplistic and high yield terms weather results from the sun heating the earth and molecules of gas and water vapour in the lower atmosphere (troposphere).

 

The example you gave relates to a concept known as the butterfly effect. That is probably best tackled in another thread however.

[Vigile]

I really like how you can take some of life's most basics, break them down and question things that the rest of us might take for granted Ruby. This is one of the values of this site; people who can offer fresh perspective and fresh questions. 

 

As for myself, I know I can't adequately answer your question. My understanding of this subject is rudimentary at best. 

[RogueScholar]

Weather systems are a bit more complex but if you can agree that the sun heats the earth and this occurs unequally, then you'll be okay. As you know the earth has a slightly tilted axis and certain areas can get more or less energy from the sun. Basically, the equator gets more and the poles get less. This creates a gradient. Basically, warmer stuff diffuses toward cooler stuff. This creates areas where this warmer air flows toward the poles. This gives rise to the so called jet stream, a large path of air moving toward the poles. Interruptions of this stream in specific areas due to a host of factors gives rise to more localised storm systems.

 

That's a pretty basic starting point and the reality is that we do not have methods for exactly predicting weather patterns. In fact the entire field of fluid mechanics that studies how things flow (fluids) relies on a set of equations that cannot be solved exactly. (Navier Stokes Equations) There are prizes, fame and riches to be had for the bad ass who can come up with methods that give exact answers however. :-)

 

Edit: I'm referring to situations involving high Reynolds numbers and turbulent flow patters for all you nerds waiting to bust my chops.

[Jeff]

Heat rises.

Cold rushes in to fill the void.

 

I could be wrong

[Fweethawt]

Thunder is god bowling.

[Guest Furball]

Thunder is god bowling.

Ha Ha Loved that one. Thanks for the laugh. 

 

 

 

[R. S. Martin]

Wonderful answers! Rogue Scholar, thanks for daring to be simplistic but that fact about the sun warming the earth being the cause for all our weather was the missing piece for me. I should probably have figured it out but I didn't. And then you added the fact about the jet stream. Those were fundamental facts I'd never heard or understood. I knew about cooler air settling to the bottom and all that. And I'd heard about the jet stream but all my life I watched the streams jets left behind when passing over so I figured that's what they're talking about. Thanks so much for clarifying. 

 

Fweethawt, not to be nasty or contradictory, but my mother--who was never wrong --told me when I was a fairly young kid that thunder is God talking. I thought it sounded like Dad throwing large pieces of lumber onto a pile but Mom corrected me and insisted we be solemn out of respect when God was speaking. I never forgot that.  

 

Except, well, then they went and built a huge electric derrick on our farm and when they opened or closed some connection, it cracked and crackled a lot like thunder. Given that, it was quite easy to believe when I was told that thunder is electrical action in the clouds. Not that I could figure out where the electricity came from, since the clouds seemed not to be wired from generators at Niagara Falls. 

 

Anyway, Vigile, I like your honesty and I don't think my brain could handle it if anyone went a lot deeper into the technicalities and scientific numbers of what makes weather systems work. I was just missing a couple basic facts. Thanks for all your responses. And yes, I saw yours, too, Jeff--heat rises and cold rushes in to fill the void. I just needed to know what reliable and consistent source causes the heat to rise in a way that creates weather systems. Hmm. Let's put that another way. I didn't realize that heat and cold on a cosmic scale created our weather systems. Now that I've heard it, it seems obvious but all these years it never occurred to me. 

[RogueScholar]

Not a problem. I'm glad my replies were helpful.