Why is Earths Girth Bulging?
The scientists are uncertain as to the reasons for this phenomenon, which was just the opposite for several decades prior to 1997, but think the answer possibly lies within long-term variation in the oceans. “Starting after 1997, the world that was getting rounder started getting more oblate [flattened at the poles],” said Christopher Cox, a research scientist at the Space Geodesy Branch of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. At first, the scientists had any number of explanations for this observed phenomenon from changes in the atmosphere to the amount of water in the oceans to ocean tidal effects. But the Earth kept getting fatter at the equator and flatter at the poles. “It has finally gotten so big that we can’t explain it with any known mechanism,” said Cox, who co-authored a paper in the August 2 issue of the journal Science on this change in shape of the Earth’s gravity field. The change in shape since 1997 is very subtle: an increase in equatorial radius
