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A STATE OF ART ON AIRBORNE LIDAR APPLICATION IN HYDROLOGY AND 
OCEANOGRAPHY: A COMPREHENSIVE OVERVIEW 
A. Mohammadzadeh a ’*, M. J. Valadan Zoej a 
a Geodesy and Geomatics Engineering Faculty, K.N.Toosi University of Technology, No. 1346, Vali Asr St., Tehran, 
Iran, Postal Code: 1996715433 - ali_mohammadzadeh2002@yahoo.com - valadanzouj@kntu.ac.ir 
KEY WORDS: LiDAR Oceanography, Hydrography, Mapping, Bathymetry 
ABSTRACT: 
Nowadays, lidar has been accepted as one of the important sensors providing accurate and dense 3D point cloud from earth surface 
terrain and water bathymetry. The basic idea of using lidar stems from the problem of measuring water depth without direct 
contacting with the water body or without any instrument mounted on the water surface in shallow regions. Bathymetric lidar that 
uses two different laser beam mounted on a flying aircraft above the water surface has proved to be a good solution. This ability 
resolves many of the industrial and military needs for accurate and precise geospatial information from water body in shallow area in 
a very rapid manner. This technology has been used in the cases which would be solved with serious difficulties using alternative 
solutions. In addition to hydrology and- oceanography, there are other important application areas which mainly are urban mapping, 
forestry, and photogrammetry. In this study, a comprehensive overview to the use of lidar technology in the oceanography and 
hydrology is discussed. In ocean and hydrography, various subjects are tackled such as: dunes and tidal flats measurement, coastal 
change and erosion, flood mapping and prediction, snow and ice measurement, water bathymetry in depths up to 70 m. Airborne 
lidar systems are rapidly developing and expanding in new applications. Integration of lidar with imaging sensors, efficient using of 
waveform information and better processing algorithms would make a great development in obtaining more realistic and accurate 3D 
models of the geospatial objects. Maybe in future, more cost effective solutions would attract the users to suite from this technology. 
1. INTRODUCTION 
Currently lidar technology has been operational used in 
different applications by many organizations and industries. In 
some specific cases, using traditional methods would take a lot 
of time and cost from the customers to fulfill their needs. For 
instance, many hydrography and oceanography organizations 
need bathymetric maps for near coastline area. Using echo- 
sounders would be dangerous, not accurate enough in shallow 
waters, time consuming, and do not give a continuous water 
depth. Alternatively, using bathymetric lidar provide accurate, 
continuous, fast depth information from a large region. There is 
no need to contact directly with the water body and this ability 
resolves many of the industrial and military needs for accurate 
and precise geospatial information from water body in shallow 
area in a very rapid manner. In this study, a comprehensive 
overview to the use of lidar technology in the oceanography 
and hydrology is discussed and various subjects are tackled 
such as: dunes and tidal flats measurement, coastal change and 
erosion, flood mapping and prediction, snow and ice 
measurement, water bathymetry in depths up to 70 m. 
2. LIDAR APPLICATIONS IN HYDROLOGY AND 
OCEANOGRAPHY 
Water hydrology modeling and watershed management is based 
on constant monitoring of the water volume over a long time 
for modeling water dynamic behavior. Flood prediction and 
flood extend modeling is one of the most important issues in the 
watershed management and usually the primary interest would 
be coastal area and rivers hydrodynamic modeling especially in 
the event of the flood. Remote sensing technology provides a 
highly fast and rich source of data for the above mentioned 
modeling which was lacking by other type of sources like 
ground based methods. Previously due to the lack of 
information, there was not good correlation between reality and 
hydrodynamic models and also the models were not complete 
enough. With the presence of Remote Sensing sensors huge 
amount of data in short period of time is available for the 
hydrologists and there is need to investigate the different 
available RS data and their suitability. River and coastal 
monitoring and modeling task require 3D information about a) 
Coast or river bottom depth, b) coast or river surface and banks 
topography (in the lowest water level), c) Vegetation height, d) 
Man-made objects near to the coast or river, e) All the objects 
that might have effect on the water current. 
A number of RS sensors have the potential of providing the 
data for the required mentioned factors and will be investigated 
in the following judgment which is more a personal opinion. 
Airborne multispectral images is capable of the recording the 
backscattered sun beam from the river bottom surface. This 
gives the possibility of indirect estimation of the water depth 
through a regression model between image recorded radiation 
and the in situ control information for validation of the model. 
The practical models have shown that airborne optical 
multispectral passive sensors demonstrate the depth 
measurements up to 6 meters with 50 cm accuracy. One should 
consider that data collected over turbid water and cloudy or 
wavy areas makes these sensors inefficient. Automatically for 
water depth more than 6 meters, the water clarity is not enough 
for accurate depth measurement. For depth more than 6 meters, 
other bathymetric sensors are used like radar images, 
Hyperspectral airborne images, and Lidar. Vogelzang 
(Vogelzang et al., 1994) proposed depth extraction from radar 
intensity image using an numerical image inversion method 
based on the fact that the water surface waves in low wind 
condition is affected by the bottom topography which higher 
magnitude surface waves result in high intensities and