Influence of the Pacific Decadal Oscillation on regional sea level rise in the Pacific Ocean from 1993 to 2012

The rate of regional sea level rise (SLR) provides important information about the impact of human activities on climate change. However, accurate estimation of regional SLR can be severely affected by sea surface height (SSH) change caused by the Pacific Decadal Oscillation (PDO-SSH). Here, the PDO-SSH signal is extracted from satellite altimeter data by multi-variable linear regression, and regional SLR in the altimeter era is calculated, before and after removing that signal. The results show that PDO-SSH trends are rising in the western Pacific and falling in the eastern Pacific, with the strongest signal confined to the tropical and North Pacific. Over the past 20 years, the PDO-SSH accounts for about 30%–40% of altimeter-observed SLR in the regions 8°–15°N, 130°–160°E and 30°–40°N, 170°–220°E. Along the coast of North America, the PDO-SSH signal dramatically offsets the coastal SLR, as the sea level trends change sign from falling to rising.