February 01, 2010

From Fair To Stormy.

Last week we experienced an unusual change in air pressure. According to the meteorologists, the variation in atmospheric pressure was unique in its extend. Within 24 hours, the pressure fell from 1044 hPa down to 990 hPa, a rare fall of more than 50 hPa.

I have an old barometer that I purchased, I believe, in Best (Home Furnishing) while living in North Carolina. It is combined with a thermometer and hygrometer as well, the last measuring the humidity of the air. I could clearly follow the fall in pressure as the indicator on the middle dial kept moving from fair to stormy.

I find it quite intriguing that the air which surrounds us and feels light and weightless actually has a certain mass. The force of the weight that it displays upon a certain area is what is called the air pressure. The air can also be compressed, that is the tiny particles, or molecules of various gases take up less room and thus the pressure elevates, or vice-versa.
The standard atmosphere (symbol: atm) is a unit of pressure and is defined as being equal to 101,325 Pa or 101.325 kPa, which corresponds to the weight of 14.696 lbs/sq2 (1.0333 kg/cm2) and is the average air pressure at sea level. This means hundreds of pounds of pressure are pressing at us from all sides and at all times. We are able to survive this pressure because the air in our bodies is under the same pressure as outside us. However, it can happen that the air around us can change suddenly and our bodies might not follow, such as when we ascent or descend in a plane. This is why we feel our ear pop, as our bodies try to equalize the difference.

Air pressure can also help us forecast the weather as well. If a high pressure system is on its way, this means cooler temperatures and clear skies. If a low pressure system is coming, the weather will be warmer, accompanied by storms and rain. Which is exactly what happened with our weather last week; we went from beautiful sunny day to a dreadful winter storm just within a course of twenty four hours.

24 comments:

A Bit of the Blarney said...

My father had a barometer and would listen to the weather and make his predictions based on HIS barometer. For him is was a game, but more often than not he was right. I miss his weather predictions. Wishing you a grand day!!! Cathy

Anonymous said...

Hi!
You may probably be very interested to know how one can manage to receive high yields on investments.
There is no initial capital needed.
You may commense earning with a money that usually goes
on daily food, that's 20-100 dollars.
I have been participating in one company's work for several years,
and I'll be glad to share my secrets at my blog.

Please visit blog and send me private message to get the info.

P.S. I make 1000-2000 per daily now.

http://theinvestblog.com [url=http://theinvestblog.com]Online Investment Blog[/url]

Reading Tea Leaves said...

I learn so many new facts from your blog Zuzana! Thank you for such an interesting read. I really like your barometer - is it an antique?

Hope the storm has passed now.

Jeanne x

Gal Friday said...

We sell these triple barometers in our shop and I am always at a loss as to how to explain what the difference is between the barometer and the hygrometer.
So... I am going to print out your simple explanation(if you don't mind!)and use it as a reference the next time someone asks me(and I'll probably make a sale that much easier)
Thanks, my scientific Lunar friend!

Margie said...

It's amazing how you can go from a beautiful sunny day to a dreadful winter storm so quickly once the weather pressure changes.
That is happened here often!
Not so much this winter though!
We have had many beautiful sunny days!
And I'm hoping for many more as I so love those sunny days!

Such an interesting post, as always!
Thank you Zuzana.

Stay warm!

Margie:)
xo

Brian Miller said...

you know i always learn something when i come by each day...my FIL has a barometer on the wall. 14 inches of snow over the weekend. 40 degrees today. snow tonight and again on saturday. wacky.

Rebecca said...

I'm with Brian...I love that your posts have such a personal touch while also educational and so very interesting...You really make science quite fascinating to me, and that's quite an accomplishment as it was never my favorite subject...:)...

I love your barometer!

steviewren said...

I am a human barometer. My body responds to low pressure with aches and pains and a general ugh feeling. On clear sunny days I am more energetic and happy. My step even feels lighter. I have a friend with retinitis pigmentosa who says she can tell the air pressure change because she can't see as well as on other days.

Nessa said...

Rabbit, Rabbit

I get headaches when the pressure is going to change drastically. I should put a needle on my forehead.

Anonymous said...

Thanks for the info on air pressure. Lets hope for high sunny days soon to come! I've made some new friends thru you, Zuzana.
Your blog is quite a natural attraction! :) The Bach

sprinkles said...

My father has always had a barometer for as long as I can remember. I never really understood why until now, after reading your post. I'd ask him what it was for and he'd say so that he could predict the weather. I was always saying, "Why can't you just watch the news and listen to the weatherman?"

Mahmud Yussop said...

I love the explanation,my good friend. This is intriguing stuff and I guess explain why scientists find so much romance in the air. I feel on air. And what a beautiful piece of equipment you've got there!! Thanks for sharing.

Donna said...

Very interesting. I know one thing for sure, I always get a headache when the barometric pressure drops.

Hugs,
Donna

Anonymous said...

[B]NZBsRus.com[/B]
Dismiss Idle Downloads With NZB Downloads You Can Instantly Search Movies, Console Games, MP3 Singles, Applications and Download Them @ Dashing Speeds

[URL=http://www.nzbsrus.com][B]NZB Search[/B][/URL]

Blogaire said...

Oh how I love Zuzana's science lessons which are always informative, never boring like they used to be at school!
There was a Barometer in my parents house and my father swore by it and you know most times it predicted correctly.
As backup we had an old donkey which definitely sensed bad weather coming and a dog that ALWAYS knew when a thunder storm was imminent.

Sharon Lovejoy said...

Hello dear Zuzana,

Fascinating, but am I unusual for getting TERRIBLE headaches when the pressure changes rapidly??

I'd love to hear from others.

Love!

Sharon Lovejoy Writes from Sunflower House and a Little Green island

Rajesh said...

Very interesting.I like the barometer with so many features.

G said...

See, I love how you're a scientist and can explain this stuff still so well to a layperson like me. I think barometric pressure is fascinating... it certainly affects me.

Unknown said...

we have thermometer in our house. Just a small one. But anyway it's almost never changing cos we don't have a drastic change of weather here.

i just wish i live where there's four season.

btw they look like clocks. very cute.

I am Denise Katipunera

Phivos Nicolaides said...

Always interesting and informative your lovely posts dear Zuzana. Have a great day my dear friend.

Anonymous said...

Hello!
Thanks for that great little lesson - great information :)

Zuzana said...

Cathy, Jeanne, Tina, Margie, Brian, Rebecca, Stevie, Nessa, The Bach, sprinkles, Mahmod, Donna, Blogaire, Sharon, Rajesh, BPG, Denise, Phillip and Michelle (welcome!) – thank you all for sharing with me your experiences with the air pressure..;) And the way it effects you.;)
My barometer is not an antique, it is only made to look that way. I love it and check it every day; both the pressure but also the humidity. I grew up with barometers, my parents always had one and my mother often recalls how I was the only one in the family always *tapping* it, when I passed it.

Thank you all for always finding the time to stop by and for leaving kind comments, they make me smile.

Xoxo
Zuzana

United Studies said...

Very interesting! I had never once even thought about a barometer, but after reading this I think it would be fun to buy one and try to predict the weather that way. I know Emma would have fun with it.

Zuzana said...

Jacki, yes I am sure Emma would enjoy knowing that this dial can predict weather.;) Always happy when you visit.;) xo