Authors: Guoqi Han Weigen Huang
Publish Date: 2009/02/20
Volume: 97, Issue: 3-4, Pages: 403-403
Abstract
Sealevel variability in the South China Sea was investigated based on satellite altimetry tidegauge data and temperature and salinity climatology The altimetric sealevel results clearly reveal three distinct amphidromes associated with the annual cycle The annual sea level is higher in fall/winter in the coast and shelf region and in summer/fall in the central sea agreeing well with independent tidegauge data Averaged over the deep basin bottom depth2000 m the annual cycle can be approximately accounted for by the steric height relative to 700 db Significant interannual sealevel change is observed from altimetry and tidegauge data The interannual and longerterm sealevel variability in the altimetric data is negatively correlated significant at the 95 confidence level with the El Niño Southern Oscillation ENSO attributed in part to the steric height change The altimetric sealevel rise rate is 10 cm/year for the period from 1993 to 2001 which is consistent with the rate derived from coastal tidegauge data and approximately accountable for by the steric height calculated relative to 700 db The altimetric sealevel steric height rise rate of 105 09 cm/year from 1993 to 2001 is much larger than that of 022 012 cm/year for the period from 1979 to 2001 implying the sensitivity to the length of data as a result of the decadal variability Potential roles of the ENSO in the interannual and longerterm sealevel variability are discussed in terms of regional manifestations such as the ocean temperature and salinity
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