COASTAL MORPHODYNAMICS

Transcription

1 COASTAL MORPHODYNAMICS PATRICIA CHARDÓN-MALDONADO, PHD, EIT Miguel Canals, Jack A. Puleo, Alec Torres-Freyermuth & Jens Figlus March 9, 2017

2 OUTLINE INTRODUCTION Meteorological Phenomena Forcing Conditions Field Study and Setup Hydrodynamic and Sediment Transport Parameters Instantaneous Measurements SWASH ZONE Storm-induced Nearshore Morphology Change Numerical Modeling

3 COASTAL ENGINEERING FLUID/STRUCTURE INTERATION COASTAL EROSION SEA- BREEZE DOMINATED BEACHES HIGHLY-ENERGETIC WAVE CONDITIONS GEOMORPHOLOGY RESILIENCE PUERTO RICO COMPLEX COASTLINE INTRODUCTION

4 INTRODUCTION ZONES INTRODUCTION

5 METEOROLOGICAL PHENOMENA Local (land/sea breezes) scale meteorological events generate air circulation due to the large temperature difference between land and sea. Cold fronts are noted by cold air advancing and displacing warmer air. LOCAL SYNOPTIC INTRODUCTION

6 FORCING CONDITIONS 1. Land & Sea breeze ( ms -1 ) 2. Gale / Storm ( > 14 ms -1 ) LAND BREEZE SEA BREEZE GALE / STORM INTRODUCTION

7 MORPHOLOGICAL CHANGE RINCON, PR NEARSHORE MORPHOLOGY

8 STORM-INDUCED NEARSHORE MORPHOLOGY CHANGE RINCON, PUERTO RICO A coupled wave-current-sediment transport numerical model was implemented to estimate the impact of storm along Rincon s coast. The Coastal Modeling System (CMS), developed by the U.S. Army Corps of Engineers, is an integrated modeling system for simulating nearshore waves, currents, water levels, sediment transport, and morphology change (Sánchez et al., 2012). NEARSHORE MORPHOLOGY

9 STORM EVENTS OFFSHORE WAVE CONDITIONS NEARSHORE MORPHOLOGY

10 STORM-INDUCED NEARSHORE MORPHOLOGY CHANGE HURRICANE SANDY NEARSHORE MORPHOLOGY

11 STORM-INDUCED NEARSHORE MORPHOLOGY CHANGE HURRICANE SANDY NEARSHORE MORPHOLOGY

12 STORM-INDUCED NEARSHORE MORPHOLOGY CHANGE HURRICANE SANDY NEARSHORE MORPHOLOGY

13 MODEL / MEASUREMENTS COMPARISON 1 Tropical Storm Isaac 1 Hurricane Sandy dz (m) Transect #1 1 Transect #1 1 1 dz (m) Transect #2 1 1 Transect #4 dz (m) Transect #4 1 1 Transect #5 dz (m) 0 Transect # Distance (m) Transect # Distance (m) NEARSHORE MORPHOLOGY Simulated morphology change Measured morphology change

14 FLUID-STRUCTURE INTERACTION SMALL-SCALE PROCESSES Small-scale processes should be related to larger spatial and temporal domains (e.g., entire foreshore) to understand the sediment transport processes governed by inner-surf and swash-zone dynamics. SWASH ZONE

15 SWASH ZONE This zone is important because: it is the primary area for beach recreation. its processes control foreshore morphological changes. within this region, groundwater discharges into the coastal ocean. it is the landward boundary condition for numerical models. serves as a buffer for hydrodynamic forcing. Chardón-Maldonado, P., Pintado-Patiño, J.C., and Puleo, J.A Advances in swash-zone research: Small-scale hydrodynamic and sediment transport processes. Coastal Engineering, doi: /j.coastaleng SWASH ZONE

16 CHALLENGES DATA GAPS High levels of surf zone turbulence, bubbles, and suspended sediment (relative to other ocean environments) can corrupt velocity measurement. Butt and Russell, 2005 SWASH ZONE

17 CHALLENGES DATA GAPS High levels of surf zone turbulence, bubbles, and suspended sediment (relative to other ocean environments) can corrupt velocity measurement. Butt and Russell, 2005 SWASH ZONE

18 HYDRODYNAMIC AND SEDIMENT TRANSPORT PARAMETERS INSTANTANEOUS MEASUREMENTS SWASH ZONE

19 SEDIMENT TRANSPORT RATES PROBABILISTIC MODELS SWASH ZONE

20 SHORELINE MOTIONS RUNUP Composed of wave setup and swash. Influenced by offshore wave characteristics, foreshore slope and morphology. Prediction of runup height (including both wave setup and swash) is of particular interest in engineering applications (i.e., improve coastal morphology response and flooding hazard models and design of coastal structures) SWASH ZONE

21 SUMMARY A detailed understanding of the waves/flows conditions in the surf zone and swash zone is essential for coastal engineers as they may cause: beach erosion coastal flooding damage to coastal structures. However, their processes are vital for: beach nourishment projects design of coastal structures Swash-zone flow interactions influence incident wave-induced hydrodynamics and therefore morphodynamics. SUMMARY

22 THANK YOU. Q & A Contact: Patricia Chardón-Maldonado, PhD, EIT patricia.chardon@upr.edu