Sea-level rise and potential drowning of the Italian coastal plains: Flooding risk scenarios for 2100

Abstract We depict the relative sea-level rise scenarios for the year 2100 from four areas of the Italian peninsula. Our estimates are based on the Rahmstorf (2007) and IPCC-AR5 reports 2013 for the RCP-8.5 scenarios ( www.ipcc.ch ) of climate change, adjusted for the rates of vertical land movements (isostasy and tectonics). These latter are inferred from the elevation of MIS 5.5 deposits and from late Holocene sea-level indicators, matched against sea-level predictions for the same periods using the glacio-hydro-isostatic model of Lambeck et al. (2011). We focus on a variety of tectonic settings: the subsiding North Adriatic coast (including the Venice lagoon), two tectonically stable Sardinia coastal plains (Oristano and Cagliari), and the slightly uplifting Taranto coastal plain, in Apulia. Maps of flooding scenarios are shown on high-resolution Digital Terrain Models mostly based on Lidar data. The expected relative sea-level rise by 2100 will change dramatically the present-day morphology, potentially flooding up to about 5500 km 2 of coastal plains at elevations close to present-day sea level. The subsequent loss of land will impact the environment and local infrastructures, suggesting land planners and decision makers to take into account these scenarios for a cognizant coastal management. Our method developed for the Italian coast can be applied worldwide in other coastal areas expected to be affected by marine ingression due to global climate change.

[1]  E. Baltsavias,et al.  Digital Surface Modelling by Airborne Laser Scanning and Digital Photogrammetry for Glacier Monitoring , 2001 .

[2]  Rae Zimmerman,et al.  Developing coastal adaptation to climate change in the New York City infrastructure-shed: process, approach, tools, and strategies , 2011 .

[3]  Kurt Lambeck,et al.  Sea level in Roman time in the Central Mediterranean and implications for recent change , 2004 .

[4]  Z. Altamimi,et al.  ITRF2008: an improved solution of the international terrestrial reference frame , 2011 .

[5]  R. Caputo,et al.  Quantitative analysis of extensional joints in the southern Adriatic foreland (Italy), and the active tectonics of the Apulia region , 2011 .

[6]  M. Taviani,et al.  A potential global boundary stratotype section and point (GSSP) for the Tarentian Stage, Upper Pleistocene, from the Taranto area (Italy): Results and future perspectives , 2015 .

[7]  Benjamin P. Horton,et al.  Expert assessment of sea-level rise by AD 2100 and AD 2300 , 2014 .

[8]  H. Sterr,et al.  Climate change and coastal zones: an overview of the state-of-the-art on regional and local vulnerability assessment. , 2003 .

[9]  G. Mastronuzzi,et al.  Middle-Late Pleistocene polycyclic evolution of a stable coastal area (southern Apulia, Italy) , 2007 .

[10]  G. Mastronuzzi,et al.  Pleistocene sea-level changes, sapping processes and development of valley networks in the Apulia region (southern Italy) , 2002 .

[11]  S. Rahmstorf,et al.  Temperature-driven global sea-level variability in the Common Era , 2016, Proceedings of the National Academy of Sciences.

[12]  J. Storms,et al.  Coastal dynamics under conditions of rapid sea-level rise: Late Pleistocene to Early Holocene evolution of barrier–lagoon systems on the northern Adriatic shelf (Italy) , 2008 .

[13]  K. Lambeck,et al.  Holocene relative sea-level changes and vertical movements along the Italian and Istrian coastlines , 2009 .

[14]  Martin Vermeer,et al.  Climate related sea-level variations over the past two millennia , 2011, Proceedings of the National Academy of Sciences.

[15]  A. Fontana,et al.  Post-LGM sedimentation and Holocene shoreline evolution in the NW Adriatic coastal area , 2008 .

[16]  L. Chiari,et al.  Lower bounds to future sea-level rise , 2012 .

[17]  C. Pignatelli,et al.  Sea level changes and geoarchaeology between the bay of Capo Malfatano and Piscinnì Bay (SW Sardinia) in the last 4 kys , 2014 .

[18]  N. Mimura,et al.  Impacts of climate change and sea-level rise on cyclonic storm surge floods in Bangladesh , 2008 .

[19]  L. Angeletti,et al.  The Middle-Upper Pleistocene Fronte Section (Taranto, Italy): An exceptionally preserved marine record of the Last Interglacial , 2014 .

[20]  Paolo Ciavola,et al.  Evaluation of coastal vulnerability to flooding: comparison of two different methodologies adopted by the Emilia-Romagna region (Italy) , 2015 .

[21]  D. Gomis,et al.  On the interpretation of the steric and mass components of sea level variability: The case of the Mediterranean basin , 2012 .

[22]  M. Snoussi,et al.  Vulnerability assessment of the impact of sea-level rise and flooding on the Moroccan coast: the case of the Mediterranean eastern zone. , 2008 .

[23]  K. Lambeck,et al.  Sea-level change along the Italian coast for the past 10,000 yr , 2004 .

[24]  Martin Vermeer,et al.  Testing the robustness of semi-empirical sea level projections , 2012, Climate Dynamics.

[25]  Remik Ziemlinski,et al.  Tidally adjusted estimates of topographic vulnerability to sea level rise and flooding for the contiguous United States , 2012 .

[26]  P. Renda,et al.  Elevation of the last interglacial highstand in Sicily (Italy): A benchmark of coastal tectonics , 2006 .

[27]  K. Lambeck,et al.  New insights on the relative sea level change during Holocene along the coasts of Tunisia and western Libya from archaeological and geomorphological markers , 2011 .

[28]  Enrico Serpelloni,et al.  Vertical GPS ground motion rates in the Euro‐Mediterranean region: New evidence of velocity gradients at different spatial scales along the Nubia‐Eurasia plate boundary , 2013 .

[29]  Grazia Pietrantonio,et al.  Flooding scenarios due to land subsidence and sea‐level rise: a case study for Lipari Island (Italy) , 2017 .

[30]  Patrick D. Nunn,et al.  Sea Level Change , 2013 .

[31]  Aslak Grinsted,et al.  Recent global sea level acceleration started over 200 years ago? , 2008 .

[32]  Karin L. Lemkau,et al.  Floating oil-covered debris from Deepwater Horizon: identification and application , 2012 .

[33]  C. Braitenberg,et al.  Sardinia Coastal Uplift and Volcanism , 2009 .

[34]  Nigel Goldenfeld,et al.  Samuel Frederick Edwards: Founder of modern polymer and soft matter theory , 2015, Proceedings of the National Academy of Sciences.

[35]  Simone Tarquini,et al.  TINITALY/01: a new Triangular Irregular Network of Italy , 2007 .

[36]  P. Hearty,et al.  Chronostratigraphic confirmation of MIS 5 age of a baymouth bar at Is Arenas (Cagliari, Italy) , 2011 .

[37]  G. Fontolan,et al.  Early cementation and accommodation space dictate the evolution of an overstepping barrier system during the Holocene , 2015 .

[38]  Pietro Teatini,et al.  Eustacy and land subsidence in the Venice Lagoon at the beginning of the new millennium , 2004 .

[39]  J. Cooper.  SEDIMENTARY PROCESSES IN THE RIVER-DOMINATED MVOTI ESTUARY, SOUTH-AFRICA , 1994 .

[40]  Luca Carniello,et al.  Self-organization of shallow basins in tidal flats and salt marshes , 2006 .

[41]  R. Nicholls,et al.  Changing extreme sea levels along European coasts , 2014 .

[42]  Giuseppe Mastronuzzi,et al.  Markers of the last interglacial sea-level high stand along the coast of Italy: Tectonic implications , 2006 .

[43]  David A. Seal,et al.  The Shuttle Radar Topography Mission , 2007 .

[44]  Ricarda Winkelmann,et al.  Future sea level rise constrained by observations and long-term commitment , 2016, Proceedings of the National Academy of Sciences.

[45]  K. Lambeck,et al.  Coastal structure, sea-level changes and vertical motion of the land in the Mediterranean , 2014 .

[46]  I. Overeem,et al.  Sinking deltas due to human activities , 2009 .

[47]  K. Lambeck,et al.  Understanding global sea levels: past, present and future , 2008 .

[48]  N. White,et al.  Sea-Level Rise from the Late 19th to the Early 21st Century , 2011 .

[49]  S. Guerzoni,et al.  Sediment budget in the Lagoon of Venice , 2008 .

[50]  S. Guerzoni,et al.  Sediment Budget in the Lagoon of Venice, Italy , 2010 .

[51]  Anny Cazenave,et al.  Sea level: A review of present-day and recent-past changes and variability , 2012 .

[52]  F. Fedele,et al.  Wave climate of the Adriatic Sea: a future scenario simulation , 2012 .

[53]  P. Lionello,et al.  Extreme storm surge and wind wave climate scenario simulations at the Venetian littoral , 2012 .

[54]  Luca Carniello,et al.  Critical bifurcation of shallow microtidal landforms in tidal flats and salt marshes. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[55]  K. Lambeck,et al.  Sea-level change during the Holocene in Sardinia and in the northeastern Adriatic (central Mediterranean Sea) from archaeological and geomorphological data , 2007 .

[56]  G. Gabbianelli,et al.  Coastal Areas at Risk from Storm Surges and Sea-Level Rise in Northeastern Italy , 1995 .

[57]  Aslak Grinsted,et al.  Trends and acceleration in global and regional sea levels since 1807 , 2014 .

[58]  Martin Vermeer,et al.  Long-term sea-level rise implied by 1.5 °C and 2 °C warming levels , 2012 .

[59]  S. Rahmstorf,et al.  Global sea level linked to global temperature , 2009, Proceedings of the National Academy of Sciences.

[60]  Piero Lionello,et al.  The Mediterranean surface wave climate inferred from future scenario simulations , 2008 .

[61]  P. Ruti,et al.  Steric sea level rise over the Mediterranean Sea: present climate and scenario simulations , 2012, Climate Dynamics.

[62]  M. Lipizer,et al.  Human impact and the historical transformation of saltmarshes in the Marano and Grado Lagoon, northern Adriatic Sea , 2012 .

[63]  Paolo Baldi,et al.  High resolution topographic model of Panarea Island by fusion of photogrammetric, lidar and bathymetric digital terrain models , 2010 .

[64]  G. Benassai,et al.  Coastal inundation risk assessment due to subsidence and sea level rise in a Mediterranean alluvial plain (Volturno coastal plain – southern Italy) , 2017 .

[65]  K. Lambeck,et al.  Sea-level change in the Mediterranean Sea since the LGM: model predictions for tectonically stable areas , 2005 .

[66]  Giorgio Spada,et al.  Sea-level rise in the Mediterranean Sea by 2050: Roles of terrestrial ice melt, steric effects and glacial isostatic adjustment , 2014 .

[67]  F. Loddo,et al.  Integration of ground-based laser scanner and aerial digital photogrammetry for topographic modelling of Vesuvio volcano , 2007 .

[68]  Mats Nilsson,et al.  Energy exchange and water budget partitioning in a boreal minerogenic mire , 2013 .

[69]  Guy Wöppelmann,et al.  Coastal sea level rise in southern Europe and the nonclimate contribution of vertical land motion , 2012 .

[70]  Kurt Lambeck,et al.  Sea level change along the Italian coast during the Holocene and projections for the future , 2011 .

[71]  M. Anzidei,et al.  The timescale and spatial extent of vertical tectonic motions in Italy: insights from relative sea-level changes studies , 2010 .

[72]  Thorkild Aarup,et al.  Understanding sea level rise and variability , 2007 .