Coastal Services
Coastline monitoring and generation of Climate Change (CC) morphological indicator
The rectification of the images and the detection of the coastline are the basic tools that have made it possible to obtain the information to carry out this type of study from TIMEX type images. A TIMEX image integrates photos every second during a representative time interval (between 10 and 20 minutes). This image allows the position of the coastline to be defined in a statistically representative way, as it averages the rise and fall of each wave on the beach slope and therefore determines a line that can be considered representative of the average level on the coast during that interval.
In order to generate morphological indicators of CC, monthly Timex images representative of different representative tide levels (low, medium and high tide) are selected. From these images, the position of the coastline is digitised, and two indicators are obtained: i) the width of the beach (estimated as the distance between a reference baseline and the coastline) at high and low tide, and ii) the supratidal and intertidal surface at high and low tide. These indicators are used to characterise the morphological evolution of beaches and to analyse trends and variability in relation to marine climatic variables (e.g. wave energy).
The indicators are also used for the validation of morphological models that can be used to analyse future scenarios and the associated evolution of beaches in response to sea level rise.
Publications
- Gainza, J., Garnier, R., Nuñez, P., Jaramillo, C., González, E. M., Medina, R., Liria, P., Epelde, I., Uriarte, A., Monge-Ganuzas, M. (2019). Accelerating beach recovery by plowing the intertidal bar: a field experiment along the northern Spanish coast. Journal of Coastal Research, 35(5), 973-984.
- de Santiago, I., Camus, P., González, M., Liria, P., Epelde, I., Chust, G., del Campo, A., Uriarte, A., 2021. Impact of climate change on beach erosion in the Basque Coast (NE Spain). Coast. Eng. 167, 103916.
- de Santiago, I., Morichon, D., Abadie, S., Castelle, B., Liria, P., Epelde, I., 2013. Video monitoring nearshore sandbar morphodynamics on a partially engineered embayed beach. J. Coast. Res. 65, 458–463.