Published online by Cambridge University Press: 24 March 2014
In May 2009, Orson van de Plassche sadly passed away. In a paper of which parts, especially the discussion section, were written after his death, new data and a revision of an existing sea-level curve are presented for the Rotterdam area (Van de Plassche et al., 2010). This comment concerns two topics addressed in the discussion section: 1) connection of their revised Rotterdam relative sea-level curve for the period 7900-5300 cal yr BP (MSL-R2; Jelgersma, 1961; Van de Plassche, 1982; 1995; Berendsen et al., 2007; Van de Plassche et al., 2010) to the sea-level curve for the same area for the period 9000-7500 cal yr BP (MSL-R1; Hijma & Cohen, 2010); 2) The role of the river gradient on the calculation of the magnitude of a sea-level jump that occurred between 8450-8250 cal yr BP (Hijma & Cohen, 2010).