FN Archimer Export Format
PT J
TI Sand spit dynamics in a large tidal‐range environment: Insight from multiple LiDAR, UAV and hydrodynamic measurements on multiple spit hook development, breaching, reconstruction, and shoreline changes
BT 
AF Robin, Nicolas
   Levoy, Franck
   Anthony, Edward J.
   Monfort, Olivier
AS 1:1;2:2;3:3,4;4:2;
FF 1:;2:;3:;4:;
C1 CEFREM Université de Perpignan Via Domitia 52 Avenue Paul Alduy Perpignan 66000, France
   Université de Caen Normandie‐CREC‐54 rue du Docteur Charcot Luc sur Mer BP 49‐14530, France
   CNRS, IRD, INRA, Coll France, CEREGEAix Marseille University Aix‐en‐Provence, France
   CNRS, UG, IFREMER, LEEISA USR 3456, Centre de Recherche de Montabo Cayenne Guyane Française, France
C2 UNIV PERPIGNAN, FRANCE
   UNIV CAEN NORMANDIE, FRANCE
   CNRS, FRANCE
   CNRS, FRANCE
UM LEEISA
IN WOS Cotutelle UMR
   copubli-france
   copubli-univ-france
IF 4.133
TC 24
UR https://archimer.ifremer.fr/doc/00635/74706/74847.pdf
LA English
DT Article
DE ;spit hook;swash bar;macrotidal inlet;longshore transport;spit breaching;overwash hotspot
AB Sand spits with distal hooks have been well documented from coasts with low to moderate tidal ranges, unlike high tidal‐range environments. Datasets from 15 LiDAR and 3 UAV surveys between 2009 and 2019 on the Agon spit in Normandy (France), a setting with one of the largest tidal ranges in the world (mean spring tidal range: 11 m), combined with in‐situ hydrodynamic records between 2013 and 2017, highlight a three‐stage pattern of spit hook evolution. Stage 1 (2009–2013) commenced with the onshore migration and attachment of a swash bar, followed by persistent spit accretion updrift of the bar and erosion downdrift because of the slow speed of bar migration in this large tidal‐range environment. In stage 2 (2013–2016), three overwash events and a 220 m‐wide breach culminating in the total destruction of the spit during winter 2015–2016 involved the landward mobilization of thousands of cubic metres of sand. These events occurred during short durations (a few hours) when spring high tides coincided with relatively energetic waves, underscoring the importance of storms in rapid spit morphological change. Strong spring tidal currents maintained the breach. Stage 3 (2016–2019) has involved new hook construction through welding of a swash bar and spit longshore extension, highlighting the resilience of the spit over the 10‐year period, and involving a positive sediment balance of 244 000 m3. The three stages bring out, by virtue of the temporal density of LiDAR and UAV data used, a high detail of spit evolution relative to earlier studies in this macrotidal setting. The large tidal range strongly modulates the role of waves and wave‐generated longshore currents, the main process drivers of spit evolution, by favouring long periods of inertia in the course of the spring–neap tidal cycle, but also brief episodes of significant morphological change when storm waves coincide with spring high tides. 
PY 2020
PD SEP
SO Earth Surface Processes And Landforms
SN 0197-9337
PU Wiley
VL 45
IS 11
UT 000543248300001
BP 2706
EP 2726
DI 10.1002/esp.4924
ID 74706
ER

EF