Global Warming Shifts the Earth's Poles

ananyo writes "Global warming is changing the location of Earth's geographic poles, according to a study published this week. Researchers at the University of Texas, Austin, report that increased melting of the Greenland ice sheet — and to a lesser degree, ice loss in other parts of the globe — helped to shift the North Pole several centimeters east each year since 2005. From 1982 to 2005, the pole drifted southeast towards northern Labrador, Canada, at a rate of about 2 milliarcseconds — or roughly 6 centimetres — per year. But in 2005, the pole changed course and began galloping east towards Greenland at a rate of more than 7 milliarcseconds per year (abstract). The results suggest that tracking polar shifts can serve as a check on current estimates of ice loss. Scientists can locate the north and south poles to within 0.03 milliarcseconds by using Global Positioning System measurements to determine the angle of Earth's spin. When mass is lost in one part of a spinning sphere, its spin axis will tilt directly towards the position of the loss — exactly as the team observed for Greenland."

Comments

Re:The opposite might also be true

[bluefoxlucid]

I was going to call stupidity on this, but then I realized they meant the axial poles. The magnetic poles have been shifting (they travel a lot, and sometimes reverse; there's been dramatic movement in the recent decade), and this can alter magma flows and screw with global weather patterns. Axial poles shift due to mass movement, which may occur from magnetic poles moving hot metal around, but also other reasons as cited.

Re:Three Gorges Dam

[ShanghaiBill]

With that said, why did they change from "centimeters" to "milliarc"? What the hell is the ratio?

A Nautical Mile is one minute of arc. Since a NM is 1852 meters, an arc second would be 1852/60 = 30.87m, so a milliarcsecond would be 3.087. So the ratio is about 3.

Re:Three Gorges Dam

[JMJimmy]

Something about this article just feels wrong. http://en.wikipedia.org/wiki/True_polar_wander feels more right - just sits better in my gut. ;)

Re:Three Gorges Dam

[vikingpower]

. Meters and kilometers are strait-line measures, and can only approximate distance on Earth (unless you want to bore through the earth).

Which is bollocks. The one is not more "curved" than the other. Both can be used to measure distance on either flat ( Euclidean ) or curved surfaces.