Sea Level Changes from 1993-2007
I saw this report from NASA's Earth Observatory about regional changes in sea-level, which were measured by Topex and Jason 1 satellites from 1993-2007.
First, check out the map below. The dark red colors indicate a sea height increase up to 8.9 inches during the 15-year period. The blue-green colored areas indicate where the sea height dropped.
Some observations from the map (there are several others if you read the link).........
1. The large-scale increase in sea-surface height across the western Pacific was mostly due to the presence of the warm-phase of the Pacific Decadal Oscillation (PDO) during the period, which resulted in a large area of above-normal sea-surface temperatures that caused a thermal expansion of the water and a rise in sea height. By the way, the PDO recently switched back to the cool phase.
2. The very thin blue area (lowering sea height) off the U.S. East Coast could be due to a decadal change in the average latitude or velocity of the Gulf Stream current.
The NASA article states that these ocean current changes over a SPAN of decades could be part of a natural cycle or indicate the beginning of a long-term change in a current as a result of human-induced climate change. They are just not sure yet.
