SEA-LEVEL CHANGES IN ZHUJIANG ESTUARY OVER LAST 40 YEARS

By extracting 1°×1° grid datum of satellite altimeters,we calculate the sea-level rising rate at Zhujiang (Pearl River)estuary as 0.30±0.05 cm/a over the period from 1993 to 2006,which is consistent with the global mean sea-level rising rate. Tidal records from six tide gauges in Zhujiang estuary show that the sea level is acceleratedly rising over last forty years (1960-2006),and it is the result of global climate warming. The sea-level fluctuations over this period are very closely correlated with ENSO activities,i, e., showing low sea-level values in E1 Nino years and high in La Nina years. Considering the good correlation between sea level and temperature and the IPCC predications on the future global temperature,we suppose the absolute sea level in Zhujiang estuary will rise by 6-14 and 9-21 cm in 2030 and 2050,respectively. If taking the factors of ground subsidence and sea-level fluctuations into account, the relative sea-level in some parts of Guangdong coast may rise by up to 30 and 50 cm in 2030 and 2050, respectively.