TY - JOUR
T1 - Cross-shore sand transport by infragravity waves as a function of beach steepness
AU - de Bakker, A. T M
AU - Brinkkemper, J. A.
AU - van der Steen, F.
AU - Tissier, M. F S
AU - Ruessink, B. G.
PY - 2016/10/1
Y1 - 2016/10/1
N2 - Two field data sets of near-bed velocity, pressure, and sediment concentration are analyzed to study the influence of infragravity waves on sand suspension and cross-shore transport. On the moderately sloping Sand Motor beach (≈1:35), the local ratio of infragravity wave height to sea-swell wave height is relatively small (HIG/HSW0. When the largest sea-swell waves are present during negative infragravity velocities (bound wave, negative correlation r0), most sand is suspended here, and the infragravity sand flux qIG is offshore. When r0 is positive, the largest sea-swell waves are present during positive infragravity velocities (free wave), and qIG is onshore directed. For both cases, the infragravity contribution to the total sand flux is, however, relatively small (IG/HSW>0.4), most sand is suspended during negative infragravity velocities, and qIG is offshore directed. The infragravity contribution to the total sand flux is considerably larger and reaches up to ≈60% during energetic conditions. On the whole, HIG/HSW is a good indicator for the infragravity-related sand suspension mechanism and the resulting infragravity sand transport direction and relative importance.
AB - Two field data sets of near-bed velocity, pressure, and sediment concentration are analyzed to study the influence of infragravity waves on sand suspension and cross-shore transport. On the moderately sloping Sand Motor beach (≈1:35), the local ratio of infragravity wave height to sea-swell wave height is relatively small (HIG/HSW0. When the largest sea-swell waves are present during negative infragravity velocities (bound wave, negative correlation r0), most sand is suspended here, and the infragravity sand flux qIG is offshore. When r0 is positive, the largest sea-swell waves are present during positive infragravity velocities (free wave), and qIG is onshore directed. For both cases, the infragravity contribution to the total sand flux is, however, relatively small (IG/HSW>0.4), most sand is suspended during negative infragravity velocities, and qIG is offshore directed. The infragravity contribution to the total sand flux is considerably larger and reaches up to ≈60% during energetic conditions. On the whole, HIG/HSW is a good indicator for the infragravity-related sand suspension mechanism and the resulting infragravity sand transport direction and relative importance.
KW - infragravity wave
KW - sand suspension
KW - sand transport
UR - http://www.scopus.com/inward/record.url?scp=84995380696&partnerID=8YFLogxK
UR - http://resolver.tudelft.nl/uuid:8877a90c-2eec-4f99-b5e0-1eaee4916d9b
U2 - 10.1002/2016JF003878
DO - 10.1002/2016JF003878
M3 - Article
AN - SCOPUS:84995380696
SN - 2169-9003
VL - 121
SP - 1786
EP - 1799
JO - Journal of Geophysical Research: Earth Surface
JF - Journal of Geophysical Research: Earth Surface
IS - 10
ER -