Posted by
Hemos
on from the getting-flatter-all-the-time dept.
RJG2 writes "MSNBC has an article stating that Earth's gravitational field has changed, becoming stronger towards the equator, thus becoming flatter. The cause has yet to be determined, but it is assumed changes in ocean levels are responsible."
I've been blaming my weight gain on candy bars and junk food. What a relief to find out it's actually just more gravity!
And maybe the shrinking waistband in all my pants is due somehow to the warping effect the extra gravity is having on space?
Change In Time?
by
ackthpt
·
· Score: 5, Interesting
I've been hearing about this on the BBC for the past couple of days. The thought that occurred to me was this: if mass is moving from the poles to the equator, will the rotation of the earth slow, even a tiny amount, but enough that we have to adjust time in a few years?
I expect so.
--
A feeling of having made the same mistake before: Deja Foobar
Back to the Future quote
by
uncoveror
·
· Score: 5, Funny
"There's that word again, heavy. Is there a problem with the Earth's gravitational pull?"
-- The Uncoveror: It's the real news.
Ask my ex workmate, it's the NT7 :)
by
jukal
·
· Score: 4, Funny
My ex-workmate is rather convinced (don't ask me why:))) that changes like this are caused by the NT7 asteroid which, he believes, will shift earth's magnetism that everything will basicly destroy. Yup, he belives it does not hit the earth, it just passes by so that everything gets wicked. He might be almost blind, but he is a hellable coder. So prepare to get extincted!
Mid life crisis?
by
CrazyDwarf
·
· Score: 4, Funny
It could be worse, we could be combing Ozone over from areas around the north pole.
-- It's easy to stand out when the general level of competence is so low.
Re:Magnetic Pole Changing
by
Zone5
·
· Score: 4, Interesting
Actually, the polarity supposedly switches roughly every 200,000 years, and according to that school of thought we're currently way overdue to the tune of about 780,000 years. See here.
Assuming you believe all that, of course. As far as I know it's just a theory.
-- "So on one hand, honey is an amazingly sophisticated and efficient food source. On the other hand it's bee backwash."
A reference on leap seconds
by
Adam+J.+Richter
·
· Score: 5, Informative
The earth's rotation is slowing anyway. This is the reason that they insert those "leap seconds" every few years to compensate
for the lost time.
At first, I did not believe that such a small
change could account for the leap seconds, but
you're right
:
Through the use of ancient observations of eclipses, it is
possible to determine the average deceleration of the Earth to be roughly 1.4 milliseconds per day per century.
[...] Over the course of one year, the difference accumulates to almost one second, which is compensated by the insertion of a leap
second into the scale of UTC with a current regularity of a little less than once per year. Other factors also affect the Earth, some in unpredictable
ways, so that it is necessary to monitor the Earth's rotation continuously.
In order to keep the cumulative difference in UT1-UTC less than 0.9 seconds, a leap second is added to the atomic time to decrease the difference
between the two. This leap second can be either positive or negative depending on the Earth's rotation. Since the first leap second in 1972, all leap
seconds have been positive and there were 22 leap seconds in the 27 years to January, 1999. This pattern reflects the general slowing trend of the
Earth due to tidal braking.
Re:Nope, it flows to the equator
by
God!+Awful
·
· Score: 4, Informative
Since the earth is spinning, the water tends to be forced to the equator by centrifugal force (although I think more correctly it's centripedal force, but whatever).
IMHO, high school physics teachers really dropped the ball in explaining this one. A whole generation of high school graduates is confused about centrifugal vs. centripedal.
A body that is spinning around an axis or orbiting around point must be under continual force. Otherwise, they would simply fly off in a straight line at a tangent to the curve. This is the centripedal force. The centrifugal force is a "pseudo force", which means that it only exists in a non-intertial frame of reference.
Basically, what happens is that when you accelerate (whether in a straight line or in a circle), your inertia feels like a force in your frame of reference. When you sit in a moving car, from your point of view you feel like you are sitting still and the car is moving. We know that when an object is at rest, the forces on it are balanced. Therefore, in your frame of reference you feel a pseudo force which balances out the force that is being applied on the car. The pseudo force is really just the effect of your inertia.
So how does this apply to the water? Well, everything on Earth has inertia, and this inertia wants to keep it going in a straight line, even though the Earth is rotating. Solid objects, such as humans are obviously kept in place by simple static friction and wind resistance. Water and air are more mobile and they are less subject to friction (although they are still very subject to air/water pressure). That is the main reason why wind and ocean currents are very obvious whereas continental drift takes centuries.
So in reality, it is the inertia of the water that makes it more buoyant at the equator. The water at the equator is spinning faster than the water at the poles, so it is slightly less subject to gravity. Therefore it bulges out, "making room" for some extra water from the poles to move towards the equator.
Actually its pretty scary...
by
Evil+Pete
·
· Score: 5, Interesting
There appears to be a movement of a huge mass from the poles to the equator over the last 4 years. The article describes how they excluded the obvious culprits: melting ice, earth movements, atmosphere etc. And finally concluded that it is related to ocean circulation. Now that gives me the creeps!
Why the creeps? Because ocean circulation changes can happen relatively quickly and are implicated in the starting / stopping of ice ages. They are crucial indicators for climate change. And when the ocean circulation changes there is nothing humans can do about it.
Hopefully it either isn't the oceans or if it is it wont have a serious effect (dont believe my own words here... but it sounds comforting). Whatever, this requires some serious investigation, just hope they got it wrong.
Slashdot Mirror
Judging by the diagram, this means that the Earth is getting shorter and fatter. Is this news? Thats what happens when you get older...
Dunno. Who cookin' the Poles?
I've been blaming my weight gain on candy bars and junk food. What a relief to find out it's actually just more gravity!
And maybe the shrinking waistband in all my pants is due somehow to the warping effect the extra gravity is having on space?
I expect so.
A feeling of having made the same mistake before: Deja Foobar
"There's that word again, heavy. Is there a problem with the Earth's gravitational pull?"
The Uncoveror: It's the real news.
My ex-workmate is rather convinced (don't ask me why :))) that changes like this are caused by the NT7 asteroid which, he believes, will shift earth's magnetism that everything will basicly destroy. Yup, he belives it does not hit the earth, it just passes by so that everything gets wicked. He might be almost blind, but he is a hellable coder. So prepare to get extincted!
It could be worse, we could be combing Ozone over from areas around the north pole.
It's easy to stand out when the general level of competence is so low.
Actually, the polarity supposedly switches roughly every 200,000 years, and according to that school of thought we're currently way overdue to the tune of about 780,000 years. See here.
Assuming you believe all that, of course. As far as I know it's just a theory.
"So on one hand, honey is an amazingly sophisticated and efficient food source. On the other hand it's bee backwash."
At first, I did not believe that such a small change could account for the leap seconds, but you're right :
Since the earth is spinning, the water tends to be forced to the equator by centrifugal force (although I think more correctly it's centripedal force, but whatever).
IMHO, high school physics teachers really dropped the ball in explaining this one. A whole generation of high school graduates is confused about centrifugal vs. centripedal.
A body that is spinning around an axis or orbiting around point must be under continual force. Otherwise, they would simply fly off in a straight line at a tangent to the curve. This is the centripedal force. The centrifugal force is a "pseudo force", which means that it only exists in a non-intertial frame of reference.
Basically, what happens is that when you accelerate (whether in a straight line or in a circle), your inertia feels like a force in your frame of reference. When you sit in a moving car, from your point of view you feel like you are sitting still and the car is moving. We know that when an object is at rest, the forces on it are balanced. Therefore, in your frame of reference you feel a pseudo force which balances out the force that is being applied on the car. The pseudo force is really just the effect of your inertia.
So how does this apply to the water? Well, everything on Earth has inertia, and this inertia wants to keep it going in a straight line, even though the Earth is rotating. Solid objects, such as humans are obviously kept in place by simple static friction and wind resistance. Water and air are more mobile and they are less subject to friction (although they are still very subject to air/water pressure). That is the main reason why wind and ocean currents are very obvious whereas continental drift takes centuries.
So in reality, it is the inertia of the water that makes it more buoyant at the equator. The water at the equator is spinning faster than the water at the poles, so it is slightly less subject to gravity. Therefore it bulges out, "making room" for some extra water from the poles to move towards the equator.
-a
How to rationalize theft.
There appears to be a movement of a huge mass from the poles to the equator over the last 4 years. The article describes how they excluded the obvious culprits: melting ice, earth movements, atmosphere etc. And finally concluded that it is related to ocean circulation. Now that gives me the creeps!
Why the creeps? Because ocean circulation changes can happen relatively quickly and are implicated in the starting / stopping of ice ages. They are crucial indicators for climate change. And when the ocean circulation changes there is nothing humans can do about it.
Hopefully it either isn't the oceans or if it is it wont have a serious effect (dont believe my own words here ... but it sounds comforting). Whatever, this requires some serious investigation, just hope they got it wrong.
Bitter and proud of it.