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Interdecadal and Interannual Mean Sea Level Variability

Interdecadal and interannual mean sea level variability 1980-1990 relative to 1930-1970 is derived from the longer RLR records. It shows levels in the later period relative to the earlier baseline period, demonstrating secular and interdecadal variability of sea level. The falling sea levels in Scandinavia and rising levels in most other places are evidence for glacial isostatic rebound and long term global sea level change.

Interdecadal and interannual mean sea level variability 1980-1990 relative to 1930-1970

variability of the period 1980-1990 relative to the period 1930-1970

Annual mean sea level can vary considerably (typically by 10's cm) from year to year in response to varying meteorological and oceanographic forcings. The interannual El Nino related changes in the Pacific are some of the largest and most well known.

Similar plots for previous years can be viewed by clicking below: 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 and 2008. Note that the choice of baseline period in these figures is a somewhat subjective one. The plots can also be used to give an indication of more recent RLR data availability The following figure shows 1996 levels relative to those averaged over the 1979-1990 baseline period. The figure demonstrates the interannual variability of sea level and also the generally good spatial coherence along coastlines evidenced in the data.