Environ Monit Assess (2011) 182:243–257
DOI 10.1007/s10661-011-1873-5
New land-based method for surveying sandy shores
and extracting DEMs: the INSHORE system
Paulo Baptista · Telmo R. Cunha · Ana Matias · Cristina Gama ·
Cristina Bernardes · Óscar Ferreira
Received: 18 April 2010 / Accepted: 18 January 2011 / Published online: 9 February 2011
© Springer Science+Business Media B.V. 2011
Abstract The INSHORE system (INtegrated
System for High Operational REsolution in shore
monitoring) is a land-base survey system designed
and developed for the specific task of monitoring
the evolution in time of sandy shores. This system
was developed with two main objectives: (1) to
produce highly accurate 3D coordinates of surface
points (in the order of 0.02 to 0.03 m); and (2)
to be extremely efficient in surveying a beach
stretch of several kilometres. Previous tests have
demonstrated that INSHORE systems fulfil such
P. Baptista (B ) · C. Bernardes
Department of Geosciences, Centre
for Environmental and Marine Studies (CESAM),
University of Aveiro, Campus Universitário
de Santiago, 3810-193, Aveiro, Portugal
e-mail: renato.baganha@ua.pt
T. R. Cunha
Department of Electronics, Telecommunications and
Informatics, Institute of Telecommunications,
University of Aveiro, Campus Universitário de
Santiago, 3810-193, Aveiro, Portugal
A. Matias · Ó. Ferreira
CIMA, Marine and Environmental Research Centre,
University of Algarve, Edificio 7, Campus de
Gambelas, 8005-139, Faro, Portugal
C. Gama
Department of Geosciences, Geophysics Centre of
Evora (CGE), University of Évora, R. Romão
Ramalho 59, 7000-671, Evora, Portugal
objectives. Now, the usefulness of the INSHORE
system as a survey tool for the production of
Digital Elevation Models (DEMs) of sandy shores
is demonstrated. For this purpose, the comparison
of DEMs obtained with the INSHORE system
and with other relevant survey techniques is pre-
sented. This comparison focuses on the final DEM
accuracy and also on the survey efficiency and
its impact on the costs associated with regular
monitoring programmes. The field survey method
of the INSHORE system, based on profile net-
works, has a productivity of about 30 to 40 ha/h,
depending on the beach surface characteristics.
The final DEM precision, after interpolation of
the global positioning system profile network, is
approximately 0.08 to 0.12 m (RMS), depending
on the profile network’s density. Thus, this is a
useful method for 3D representation of sandy
shore surfaces and can permit, after interpolation,
reliable calculations of volume and other physical
parameters.
Keywords Topography · Total station ·
Beach morphology · Beach volume
Introduction
To study processes that are related to storm im-
pact, coastal erosion and morphodynamic charac-
terisation, it is important to gather good-quality