Tutorial - Satellite derived bathymetry for intertidal zones


Mr Wagner Luiz Langer Costa

Problem background

Prediction of coastal flooding events within New Zealand. Important to have some capability to describe the event, and its impact on the environment. An area of particular concern is the estimation of bathymetry data for estuaries.

How to determine bathymetry

A number of parameters are taken into consideration when arriving at a calculation related to sea level including: mean sea level, astronomical tide, storm surge, wave run-up, fluvial discharge and vertical land motion. There are three main ways in which bathymetry can be calculated. These include, RTK - Real-time kinematics, Echo sounders and LiDAR, Remote Sensing. Of the three, Remote Sensing is the most economical, however it suffers from the lowest accuracy of the three approaches.

The Copernicus sentinel

The Copernicus programme uses satellites for earth observation missions with an intended outcome being the delivery, free of charge, of data captured using these instruments.

How well can we predict flooding events in areas where we don't have good bathymetric data?

Objectives - Generate satellite derived bathymetry measurements for all estuaries within New Zealand, especially those having little, or non-existent bathymetric data.

Study area

This research will be conducted within Tauranga Harbour, Bay of Plenty geographic area.

Project challenges

Need to process terabytes of raw data in order to arrive at a satisfactory conclusion. Processing must be concluded within a finite time window.


Extract data from Google Earth Engine. Estimate bathymetry and compare to results obtained using LiDAR.

Notebook: 'Estimating bathymetry in intertidal zone from sentinel ESA satellite images'

Google Colab provides an environment for hosting and executing of Jupyter notebooks. Colab frees the researcher's personal computer for other tasks with the computational workload executed on cloud based resources.