Reply to comment Reply to comment by C. Morhange, G. Bony, C. Flaux & M. Shah-Hosseini on “Sea level changes since the Middle Ages along the coast of the Adriatic Sea: The case of St. Nicholas Basilica, Bari, Southern Italy” Rossella Pagliarulo a, * , Fabrizio Antonioli b , Marco Anzidei c a CNR e Research Institute for Geo-Hydrological Protection (IRPI), Via Amendola, 122/I, 70126 Bari, Italy b ENEA e National Agency for New Technologies, Energy and Environment, Rome, Italy c Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy article info Article history: Available online 11 April 2013 We are thankful to C. Morhange, G. Bony, C. Flaux & M. Shah- Hosseini for their comment to our paper: “Sea level changes since the Middle Ages along the coast of the Adriatic Sea: The case of St. Nicholas Basilica, Bari, Southern Italy”. We want to underline that the paper is not addressed to reconstruct a new sea level curve for this region for the last 1000 years, as they have stated in the comment. Indeed, the goal of our research was clearly expressed in the introduction and summarized as follows: i) to give a contribution to calibrate and adjust the predicted values of relative sea level rise for the last 1000 years; ii) to test the reliability of data coming from the water table and compared them to the relative sea level stand; iii) the possibility to use a new type of marker which differs from those commonly used (see Lambeck et al., 2010), i.e. the elevation of the pavements of the crypt of St. Nicholas Basilica with respect to the water level of the groundwater. In fact, this structure recorded the evidence of the water levels inside the crypt, being repeatedly flooded by the groundwater. The latter is hydraulically connected with the nearby sea. The data of the multiple floor levels raised to avoid flooding, the values of the replacements and the sequence of the events are obtained from the very detailed report by Schettini (1957), that includes in situ observations, stratigraphic logs and geomechanical tests. These investigations were done during the restoration works and grouting treatments aimed to definitely solve the flooding problems inside the crypt that prevented its accessibility. We underline that the Basilica is located at less than 90 m from the current coastline along which were built more breakwaters to protect the coast from continuous sea level rise and subsequent erosion (see Figs. 1 and 2). Additionally, we recall that the crypt has been closed since the beginning of the XX century due to contin- uous flooding, even during dry periods. The particular location of the Basilica, built so close the coastline, allows the authors to use these observations and discuss them with respect to the most recent sea level rise predictions affecting the Italian region since the Last Glacial Maximum. In the following section, we clarify our results and interpretations. In a coastal area and in presence of a karst aquifer as with the object of this paper (see Fig. 3), the relationship between sea level and water table is driven by the GhybeneHerzberg equation. The first physical formulations of saltwater intrusion were made by W. Badon-Ghyben (1888e1889) and A. Herzberg (1901), thus called the GhybeneHerzberg relation. They derived analytical solutions to approximate the intrusion behavior, which are based on a number of assumptions that do not hold in all field cases. In the equation, z ¼ r f  r s  r f  h the thickness of the freshwater zone above sea level is represented as h, while below sea level is represented as z. The two thicknesses h and z, are in relationship by r f and r s where r f is the density of freshwater and r s is the density of saltwater. Freshwater has a density of about 1.000 g per cubic centimeter (g/cm 3 ) at 20  C, whereas that of seawater is about 1.025 g/cm 3 . The equation can be simplified to z ¼ 40h: * Corresponding author. E-mail address: r.pagliarulo@ba.irpi.cnr.it (R. Pagliarulo). Contents lists available at SciVerse ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint 1040-6182/$ e see front matter Ó 2013 Elsevier Ltd and INQUA. All rights reserved. http://dx.doi.org/10.1016/j.quaint.2013.03.038 Quaternary International 303 (2013) 230e232