TY - JOUR

T1 - The Tides They Are A-Changin': A Comprehensive Review of Past and Future Nonastronomical Changes in Tides, Their Driving Mechanisms, and Future Implications

T2 - A comprehensive review of past and future non‐astronomical changes in tides, their driving mechanisms and future implications

AU - Haigh, Ivan D.

AU - Pickering, Mark D.

AU - Green, J. A. Mattias

AU - Arbic, Brian K.

AU - Arns, Arne

AU - Dangendorf, Sonke

AU - Hill, David F.

AU - Horsburgh, Kevin

AU - Howard, Tom

AU - Idier, Deborah

AU - Jay, David A.

AU - Jaenicke, Leon

AU - Lee, Serena B.

AU - Mueller, Malte

AU - Schindelegger, Michael

AU - Talke, Stefan A.

AU - Wilmes, Sophie-Berenice

AU - Woodworth, Philip L.

PY - 2020/3

Y1 - 2020/3

N2 - Scientists and engineers have observed for some time that tidal amplitudes at many locations are shifting considerably due to nonastronomical factors. Here we review comprehensively these important changes in tidal properties, many of which remain poorly understood. Over long geological time scales,tectonic processes drive variations in basin size, depth, and shape and hence the resonant properties of ocean basins. On shorter geological time scales, changes in oceanic tidal properties are dominated by variations in water depth. A growing number of studies have identified widespread, sometimes regionally coherent,positive, and negative trends in tidal constituents and levels during the 19th, 20th, and early 21st centuries.Determining the causes is challenging because a tide measured at a coastal gauge integrates the effects of local, regional, and oceanic changes. Here, we highlight six main factors that can cause changes in measured tidal statistics on local scales and a further eight possible regional/global driving mechanisms. Since only a few studies have combined observations and models, or modeled at a temporal/spatial resolution capable of resolving both ultralocal and large‐scale global changes, the individual contributions from local and regional mechanisms remain uncertain. Nonetheless, modeling studies project that sea level rise and climate change will continue to alter tides over the next several centuries, with regionally coherent modes of change caused by alterations to coastal morphology and ice sheet extent. Hence, a better understanding of the causes and consequences of tidal variations is needed to help assess the implications for coastal defense, risk assessment, and ecological change

AB - Scientists and engineers have observed for some time that tidal amplitudes at many locations are shifting considerably due to nonastronomical factors. Here we review comprehensively these important changes in tidal properties, many of which remain poorly understood. Over long geological time scales,tectonic processes drive variations in basin size, depth, and shape and hence the resonant properties of ocean basins. On shorter geological time scales, changes in oceanic tidal properties are dominated by variations in water depth. A growing number of studies have identified widespread, sometimes regionally coherent,positive, and negative trends in tidal constituents and levels during the 19th, 20th, and early 21st centuries.Determining the causes is challenging because a tide measured at a coastal gauge integrates the effects of local, regional, and oceanic changes. Here, we highlight six main factors that can cause changes in measured tidal statistics on local scales and a further eight possible regional/global driving mechanisms. Since only a few studies have combined observations and models, or modeled at a temporal/spatial resolution capable of resolving both ultralocal and large‐scale global changes, the individual contributions from local and regional mechanisms remain uncertain. Nonetheless, modeling studies project that sea level rise and climate change will continue to alter tides over the next several centuries, with regionally coherent modes of change caused by alterations to coastal morphology and ice sheet extent. Hence, a better understanding of the causes and consequences of tidal variations is needed to help assess the implications for coastal defense, risk assessment, and ecological change

KW - tides

KW - mean sea level

KW - tectonics

KW - flooding

KW - erosion

U2 - 10.1029/2018RG000636

DO - 10.1029/2018RG000636

M3 - Review article

VL - 58

JO - Reviews of Geophysics

JF - Reviews of Geophysics

SN - 1944-9208

IS - 1

M1 - e2018RG000636

ER -