Assessment of coastal erosion rates off the pacific coast of Panama

Coastal erosion has its roots in complex natural and anthropogenic effects. To advance in identifying these roots, erosion and accretion rates were defined for the Pacific coast of Panama. Satellite images spanning 20 years indicated an erosion rate between 2 – 4 m/yr while greater values of 6 m/yr were obtained via orthomosaics from UAV flyovers between 2020 and 2023. Punta Chame and Farallon are among the most erosional sites evaluated in this period, with maximum erosional rates of 20 m/yr. Averaged accretion rates with satellite images and UAV flyovers remained close to 2 m/yr. Coastal hydrodynamics average values were obtained from previous studies using numerical simulations and are used to characterize the sites. Due to the scarcity of in situ measurements (i.e. water level, wave spectrum), estimations were made to define the dominant erosional forcing at relevant coastal sites. The mean significant wave height was 0.5 m where the most erosional spots were identified i.e. Punta Chame and Farallon, and it coincides with the largest tidal range of 4-5 m within Panama's Pacific coast. Future work requires in situ measurements to understand the seasonality of erosional spots along with the defining hydrodynamics along with sediment analysis from continental rivers.