Global sea levels rose have risen, possibly faster than ever, in the last 20 years. California's coast is the exception. Now, scientists at the Scripps Institute of Oceanography in San Diego say they can explain why.
The Scripps team examined something called wind stress variability – the pressure of wind over open ocean is one indicator of a regional climate cycle that influences sea level. They found more wind stress than anyone has measured since the 1970s, and they say that may signal a dramatic shift in the regional climate cycle.
Right now, it’s pretty cold on large patches of the Pacific Ocean surface; that’s caused by colder water welling up from the deep. If the climate cycle shifts and less cold water reaches the surface, the water there will warm up – and because heat expands, sea levels could bump up pretty quickly.
Since the 1990s, sea level’s been rising about an eighth of an inch a year on average for the planet. The new study Scripps scientists have sent to press suggests that the Pacific Ocean off North America could catch up to that rate within a decade.