Archaeological, Geomorphological and Cartographical Evidence of the Sea Level Rise in the Southern Levantine Basin in the 19Th and 20Th Centuries
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Quaternary International xxx (xxxx) xxx–xxx Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Archaeological, geomorphological and cartographical evidence of the sea level rise in the southern Levantine Basin in the 19th and 20th centuries ∗ E. Tokera,b, , J. Sharvitc, M. Fischerd, Y. Melzere, O. Potchterf a Kibbutzim College, Mordechai Namir 149, Tel Aviv-Yafo, Israel b Porter School of Environmental Studies, Tel-Aviv University, Israel c Underwater Archaeology Unit of the Israel Antiquities Authority, Rockfeller Museum, Jerusalem, Israel d Institute of Archaeology of Tel-Aviv University, Israel e Survey of Israel, Lincoln St 1, Tel Aviv-Yafo, Israel f Department of Geography, Man and Environment, Beit Berl College, 44905, Israel ARTICLE INFO ABSTRACT Keywords: Sea level variability affected by sea water mass is strongly associated with global, regional and local climate. In Sea level this context, the eastern Mediterranean Sea has been intensively investigated in recent decades because of its Archaeological sea level indicators sensitivity to climatic and environmental variables, due to the influence of the Eastern Mediterranean Transient Historical maps (EMT). The sea level in Israel during the Crusader period (12th-13th centuries CE) was found to be 19th century −0.5 ± 0.20 m relative to the present mean sea level (MSL). The difference between the Crusader sea level and Acre the present-day MSL raises some questions which bring us to the aim of this study: estimating the timeline of the Jaffa Caesarea changes in sea level elevation in the eastern Mediterranean over the last two centuries. Archaeological evidence from areas of low tidal range, such as the Mediterranean Sea, can provide significant information on sea level changes for times when instrumental measurements where not yet available (e.g., before 1955 in Israel). The method employed in this study integrates two dimensions: The vertical—estimating the changes in sea levels relative to the present MSL, based on archaeological evidence; and the horizontal—determining the coastline changes, based on coastal architectural and geomorphological structures appearing in historical maps. Both the structural and the cartographic evidence for sea level changes date to the 19th Century, and indicate a rise of 0.36 m over the last two centuries. Findings attesting to horizontal changes, indicate a gradual migration of the coastline landward, to the east since 1863 and a rapid change in the coastal geomorphology at the beginning of the 20th century. The sea level increase from the 19th century might be, in part, a consequence of regional trends and, in part, a result of a gap between method accuracy (archaeology and modern measurements). Nevertheless, the drastic change in the geomorphology of the coastline may indicate an extreme meteorological event, such as a storm at sea, accom- panied by a local rise of sea level, but further research is required to verify this. 1. Introduction Sea level measurements reflect a vertical movement of sea water in relation to the adjacent land, which can be influenced by both vertical Sea level variability that is a result of changes in sea water mass is land movements and variability in ocean volume and density (Lambeck strongly associated with global, regional and local climate changes and Purccel, 2005; Peltier, 2004). (Jevrejeva et al., 2006; Milne et al., 2009; Church and White, 2011; The majority of coastlines in the eastern Mediterranean have been Alley et al., 2005; Douglas, 2000; Fairbanks, 1989). In this context, the identified as tectonically and isostatically unstable in the last two mil- Mediterranean Sea has been intensively investigated in recent decades lenia (Lambeck et al., 2011; Antonioli et al., 2007; Ferranti et al., 2006; since it is sensitive to climatic and environmental variables (Tsimplis Pirazzoli, 2005; Anzidei et al., 2010; Morhange et al., 2006). This and Baker, 2000; Tsimplis and Josey, 2001; Klein et al., 2004; Vigo makes it complicated to monitor and assess the land's movements in et al., 2005). order to associate sea level variability with climate changes. In the ∗ Corresponding author. Kibbutzim College, Mordechai Namir 149, Tel Aviv-Yafo, Israel. E-mail addresses: [email protected] (E. Toker), [email protected] (J. Sharvit), fi[email protected] (M. Fischer), [email protected] (Y. Melzer), [email protected] (O. Potchter). https://doi.org/10.1016/j.quaint.2019.05.015 Received 11 February 2019; Received in revised form 12 May 2019; Accepted 13 May 2019 1040-6182/ © 2019 Published by Elsevier Ltd. Please cite this article as: E. Toker, et al., Quaternary International, https://doi.org/10.1016/j.quaint.2019.05.015 E. Toker, et al. Quaternary International xxx (xxxx) xxx–xxx another (Tsimplis et al., 2006; Vigo et al., 2005). Scholars relate these findings to the Eastern Mediterranean Transient (EMT) and to other environmental and meteorological factors. It is these negligible land movements and the sensitivity to climatic changes that make the Israeli Mediterranean coastline a significant lo- cation for the research of sea levels and climate changes. Sea level measurements taken in Israel continuously since 1958 show that the mean sea level (MSL) is 0.055 m above the Israel Geodetic Datum (Shirman, 2004; Toker et al., 2012). Based on this data, ac- cording to Auriemma and Solinas’ (2009) method, the present MSL along the Israeli coastline is calculated as 0.06 m (Toker et al., 2012). Estimates of past MSL rely largely on archaeological indicators along the Israeli coastline (Flemming, 1969; Sneh and Klein, 1985; Nir and Eldar, 1986; Sneh, 2000; Sivan et al., 2001, 2004; Galili et al., 2007; Galili and Nir, 1993; Nir, 1997; Toker et al., 2012). Archaeological evidence from areas of low tidal range, such as the Mediterranean Sea, can provide significant information on sea level changes; namely, coastal structures that were constructed with deliberate relation to the sea can be used as indicators of the sea level at the time of their con- struction (Lambeck et al., 2004).Archaeological evidence of past sea level (SL) dating as far back as ∼6900 BCE (∼8850 BP) (Glili and Nir, 1993) is scattered along the Israeli coastline. There are two methods of determining changes in sea level using archaeological evidence (Vunsh et al., 2017). The first based on direct evidence provided by man-made structures along the coastline, which were originally directly related to sea level at the time they were constructed and functioning (e.g. sea fortress foundations and drainage outlets) (Auriemma and Solinas, 2009; Toker et al., 2012). The second indirect evidence involves in- termediate factors, between man-made structures and sea level. For instance, the coastal wells required water table levels which lean and adjust to sea-level (Sivan et al., 2004; Marcus, 1991; Nir and Eldar, 1986). Our study focuses on direct findings, which provide evidence for sea levels over the last 200 years when the land adjacent to the sea has been relatively stable. Frequent changes of ruling powers during this period Fig. 1. Map of study area. enable dating the archaeological SL evidence to relatively short time ranges of around a century each. The two exceptions are evidence from – 1970's, these difficulties were discussed regarding the tectonic and neo- the Mamluk period (1291 1517), which was not sea oriented and left tectonic stability of the Mediterranean coastline of Israel. Discourse on little archaeological SL evidence, and from the days of the Ottoman determining stability or instability became intense and focused in the Empire, which ruled in the Holy Land for 400 years, often making it ffi fi 1990s on the coastline of Caesarea (Neev et al., 1973; Mart and di cult to date its remains to a speci c time within this span. The Perecman, 1996). However, recent studies show that for at least the last paucity of coastal evidence from these two adjacent periods forms a gap two millennia land movements along the Israeli Mediterranean coast- in SL measurements between the end of the Crusader period (1291) and line (as a result of both isostatic and tectonic movement), have been employment of modern measurements in Israel (1958). The exceptions ff negligible (Schattner et al., 2010; Gvirtzman et al., 2008; Sneh, 2000; are two wells in Ja a and Acre dating to ca.1700 (Toker et al., 2012; Sivan et al., 2001, 2004; Toker et al., 2012). It is for this reason that the Vunsh et al., 2017). Israeli coastline, located on the southeastern edge of the Mediterranean The sea level in Israel during the Crusader period was found to be − Basin (Fig. 1)reflects sea level and climate variability, with land 0.5 ± 0.20 m relative to the present MSL (Toker et al., 2012). A movement being a minimal factor (Sivan et al., 2001, 2004; Anzidei study of the Crusader period MSL in Malta produced similar results fi ff et al., 2010; Toker et al., 2012). Moreover, although nine earthquakes (Furlani et al., 2013). The signi cant di erence between the Crusader have been documented off the eastern Mediterranean coastline since and the present-day MSL raises two questions: how was this 1837 none of them impacted the Israeli coastline (Salamon et al., 2007, 0.5 ± 0.20 m gap closed and when did this change take place? 2010). Furthermore, two tsunami waves were documented in the Le- The aim of this study is therefore to determine the course of the vant one in 1759 as a result of earthquakes in Lebanon, and the second changes in MSL in the eastern Mediterranean Sea during the last two fl off the Israeli coastline in 1856 (Zohar, 2017). Neither of these tsunami centuries, as re ected in archaeological evidence scattered along the events have been shown to have altered the Israeli coastline.