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"Yu et al. describe how they "dated massive Porites and microatolls on the reef flats of Younshu and Meiji Reefs, Nansha area, southern South China Sea using high-precision thermal ionization mass spectrometric (TIMS) U-series dating techniques,""....."The seven scientists report that "at least six mortality events occurred simultaneously on both reefs (e.g. in 1869-1873, 1917-1920, 1957-1961, 1971, 1982-1983 and 1999-2000 AD), reflecting the occurrence of large-scale regional events." In addition, they say that "many of these mortality events appear to correlate in time with historic El Niño events, and were probably related to El Niño-induced high sea surface temperature bleaching.""