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Is Global Warming Behind Earth's Gravity Shifting?
MichaelH writes "The good folks at JPL along with the Royal Observatory of Belgium have an explanation for the recent changes in Earth's magnetic field: the melting of sub-polar glaciers causing a mass shift towards the equator. Starting in 1997, a noticeable change in Earth's gravitational field was observed; Earth was beginning to develop a 'bulging waistline.' Sounds like it's time for a diet with fewer greenhouse gases...."
Earlier, I had read a cnn blurb about global warming which contained no useful information. Finally, the whole global warming thing is explained:
Natural variability may be behind the changes, but human activity might also be to blame, scientists said.
That's what I call "pinning it down"!
> the melting of sub-polar glaciers causing a mass shift towards the equator.
Wouldn't this cause the earth's rotation to slow down? (spinning in the chair experiment). With super-accurate GPS and atomic clocks, I would think this would be measureable.
-metric
Nice article overall, but what the hell is up with that picture? If the Earth bulged that much, we'd all have noticed the incredible changes in gravity between 45 degree N and 0 and 90 degree north. I mean, yikes, that's gotta be at least a 10% difference between the two Earth-like planets in that picture.
Realistically, the shift much be vanishing fractions of a percent, and you wouldn't be able to find a difference between the two Earths ("pre-bulge" and "post-bulge"), even in principle, on a low-resolution picture like that; the effects they are talking about would be sub-pixel, to say the least.
I'd do the math, but there aren't any numbers in the linked text and it's too late to go out and try to find them. (Perhaps someone else will... I'll lay my money down on, ohhh, within an order of magnitude of "one ten-millionth of a pixel difference" between pre- and post-bulge Earth.)
Yes, yes, everything is a theory. In this case, however, global warming is a symptom . The theory is that we humans are causing or helping the slide toward global warming, and this theory has nowhere near the ratio of for/against evidence that relativity or darwinian evolution has, and those two are still contested today.
IM(no)HO, this is a flawed analogy on many levels. The general public has more knowledge (read:only a very little) about the average bank vault than the average climate scientist has about climate change through the centuries, nevermind millenia.
I'd like to see a poll of 'the vast majority of the world's scientists' before I take that statment at anything more than '4 out of 5 dentist recommend x brand. Sure, global warming looks like it could be a problem, and it's possible that human activity affects it in a grander scale than the butterfly on japan affects the climate in florida. It's easy to postulate possibilities.
We can predict weather based on patterns, but we still can't predict it based on causes other than other weather. We know, for instance, that in the northern hemisphere after several months of generally warm and hot weather it will then have several months of generally cool and cold weather. This is a generic weather cycle. We can't predict on any more of a minute scale other than observing what weather is already happening and what has happened with that kind of weather before (ie, clouds over chicago generally mean there will be clouds over michigan soon, and depending on the type of cloud may or may not dump water, etc)
What global warming used to be was "The world is getting warmer, why is that?" Now we're finally to the part that scientists are seeing patterns in geological history where such large scale changes occured, in concert with other large changes (magnetosphere, etc). It will likely be found out that this is another, extremely long, cycle we are moving around in that we are only now discovering (in the past 100 years) because only now have we had the record correlating ability to do so.
Again, I'm not saying it's untrue that humans are affecting global climate change (I'm sure we are) but the level and amount of change caused by us is what's in play here.
What irks me is that people are using it as a crutch for pollution change. If pollution change is a good thing, it should be able to stand on what we know it causes right now, rather than on the possible future eventuallities.
Global warming is not a crutch to be used to prop up environmental change. I believe in passing environmentally sensible policy, but if people keep putting global warming out as the reason for these regulations, then when global warming is found to be a natural cycle in the earth, environmental policy will fall on its rear end and won't be able to get up by itself for another decade or two, even when it's also shown that we may be accelerating the change.
-Adam
If having a strong, well defined opinion is trolling, then put me under a bridge with a toll box.
About extremists or fanatics: The world needs them, there is a place for them in society. They shouldn't be offended by being called extremists or fanatics - they intend to pull us in a direction by representing a view that is so far from reality that soon the general public doesn't view the center as unnatural, since there are views that are far stronger. This gentle tugging and pulling is needed to affect change.
The article is about Earth's gravity shifting -- like it says in the title of the post. Why does the body of the post mention "recent changes in Earth's magnetic field"? Does /. know something about a unified theory that physicists don't?
There have always been people entrenched in their fields who will defend nearly to the death the reputations they built for themselves. In face of any findings to the contrary.
Read Kuhn's 'The Structure of Scientific Revolutions' or any number of other books on the philosphy of science.
No, 'thousands of PhDs' doesn't automatically impress us. They have their grant funding to think of, and if there isn't an emergency how will they fund the new lab benches?