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NAUTICAL CHARTING APPLICATIONS OF PHOTOGRAMMETRY AND REMOTE SENSING 
A. RB. Kilbride 
Hydrographic Office, U.K. 
Ministry of Defence. 
1428 
ABSTRACT: 
This paper describes a practical application of photogrammetry and remote sensing in the 
context of nautical chart compilation and revision. 
Photogrammetry represents a detailed, accurate and cost effective source of data in the 
nearshore zone particularly in U.K. home waters. 
Satellite imagery is also used to resolve problems arising from the receipt of conflicting 
data and in many parts of the world forms the basis for coastline or positioning of dangers 
to navigation. 
The advantages and limitations of various 
hydrographic point of view. A number of case studies are presented in order to illustrate 
a variety of charting applications. 
types of imagery are considered from a 
KEYWORDS: Photogrammetry, Space Imagery, Nautical Charting, Navigation. 
1. INTRODUCTION 
The purpose of this paper is to describe a 
practical use of photogrammetry and remote 
sensing in a production environment, namely 
as a source Of data for nautical chart 
compilation and revision. 
The advantages and limitations of aerial 
photography and various types of satellite 
imagery are considered from a hydrographic 
point of view and a number of case studies 
presented. 
2. BACKGROUND 
The Hydrographer is concerned with the 
collection, compilation and dissemination 
of certain categories of data relating to 
the marine environment, mainly 
hydrographic, geophysical and 
meteorological. Some of these data are 
measured in the field by his own personnel, 
but the majority are collected from other 
sources outside his direct control. The 
data are collected on behalf of the Royal 
Navy for a variety of defence needs, and 
also in support of navigation in general. 
In order to meet the needs of the Royal 
Navy and international shipping, 
Hydrographer publishes a series of 3350 
navigational charts affording worldwide 
cover together with associated publications 
such as Sailing Directions, Lists of Lights 
and. Radio Aids, and. Tidal Prediction 
Tables. The series of charts is subject to 
maintenance by Admiralty Notices to 
Mariners and regular New Editions. It is 
highly regarded by the mariners of the 
world, and is considered pre-eminent among 
other world series. However, the Admiralty 
chart will only. retain its.place. if it 
carries up-to-date information which is 
well presented in a convenient form. 
Hydrographer's basic aim is to maintain the 
Admiralty chart series in an accurate, 
adequate and up-to-date condition. 
However, this is an immense task which 
cannot be fully met by the resources 
507 
currently available to hydrographic 
surveyors or likely to be available in the 
future. Only 20$ of the UK continental 
shelf has been surveyed to modern 
standards. Comparative figures for the 
rest of the world are not available, but in 
many cases the situation is even worse. It 
is still true to say that. some ‘of the 
world's largest vessels pass through waters 
which were last surveyed more than 100 
years ago or, indeed, which have never been 
surveyed. It is for this basic reason that 
hydrographic offices have become interested 
in the application of photogrammetry and 
remote sensing to nautical charting. 
3. USES OF PHOTOGRAMMETRY 
The use of photogrammetry within the 
Hydrographic Office is well established and 
aerial photography has long been recognised 
as a valuable source of data in the 
nearshore zone. Information is provided 
for the benefit of both the hydrographic 
surveyor and nautical chart compiler. 
Photogrammetry is capable of providing a 
variety of hydrographic data in a cost 
effective fashion. The Hydrographic Office 
makes use of large scale colour photography 
acquired at a low tidal state. This 
photography is processed on traditional 
analogue stereo plotters such as the Wild 
A8 and B8 and also using an Intergraph 
Inter Map Analytic system. 
Where mapping is deficient, topographic 
information can be derived emphasizing 
items of significance to the mariner. 
Coastline can be plotted as an accurate 
contour at Mean High Water Springs together 
with a detailed depiction of the intertidal 
zone, including drying heights. Where the 
water is sufficiently clear, submerged 
features such as rock and coral pinnacles 
can be detected.  Nearshore depths can be 
accurately measured applying a correction 
for the effect of the refraction of light 
through seawater.