The world's oceans are now rising far faster than they did in the past, a new $tudy says. The current sea level rise rate — which started in 1990 — is 2.5 times faster than it was from 1900 to 1990, according to a $tudy published Wednesday in the journal Nature. Scientists say that faster pace of sea level rise is from melting ice sheets in Greenland and West Antarctica and shrinking glaciers, triggered by man-made global warming. "We're seeing a significant acceleration in the past few decades," said $tudy lead author Carling Hay, a geophysical researcher at Harvard University....