Symposium on Remote Sensing for Resources Development and Environmental Management/Enschede/August 1986 
© 1987Baikema, Rotterdam. ISBN 90 6191 674 7 
973 
Remote sensing applications: An outlook for the future 
Herman Th. Verstappen 
International Institute for Aerospace Survey and Earth Sciences (ITC), Enschede, Netherlands 
ABSTRACT: To minimize the risk that predictions on the future of remote sensing applications are mere specu 
lations, the author first analyses the developments in this field during the last few decades and specifies 
present trends. Thereafter some extrapolations to a period of approximately equal length in the future are 
given. In the context of this 7th symposium of Commission VII, ISPRS, it is considered appropriate to use the 
1st symposium, held in Delft, 1962, as a starting point and to look forward to the 14th symposium in the year 
2014. 
The author tries to weigh the future role in resource surveying of high-resolution satellites, low-resol 
ution satellites and aircraft of various kinds. Recording systems in the photographic, thermographic and 
microwave bands are treated separately and the changing relationships between resource surveyors and photo- 
grammetrists also are touched upon. The growing importance of optimal organization and utilization of the 
massive amount of data gathered by way of geographic information systems (GIS) is indicated and finally the 
necessity of matching space technology with the immediate and future needs of the human race is emphasized. 
INTRODUCTION 
Summarizing the outcome of a large Symposium, like 
the present 7th symposium of Commission VII, of the 
International Society of Photogrammetry and Remote 
Sensing (ISPRS) is a difficult task, particularly if 
it has to be done at the closing session and thus 
without the possibility of data analysis, selection 
and compression provided by the filtering process of 
quiet contemplation. Venturing an outlook for the 
future may even be considered hazardous under such 
conditions if there are no clear-cut trends of de 
velopment. Fortunately in the field of remote sen 
sing applications, at least some indications can be 
detected that may serve as a basis for extrapolation 
into the future. Although this fact makes my task 
today somewhat easier, I prefer to take two precau 
tions to limit the chances of arriving at erroneous 
conclusions. 
First, I think it is wise to briefly view the 
developments during the last quarter century by com 
paring the state-of-the-art in 1962 when the 1st 
symposium of Commission VII was held at ITC, then in 
Delft, with the present situation as reflected in 
the papers presented and the discussions held during 
this 7th symposium in Enschede, 1986. 
I will then, as a second precaution limit my at 
tempt to extrapolate these trends to another period 
of similar length, as will be reflected —assuming 
that itty guesswork is correct— in the proceedings of 
the 14th symposium of Commission VII in the year 
2014. A longer prediction period seems rather un 
realistic. 
Thereafter I will try to refine the extrapolation 
by introducing present technological trends and 
users' needs as factors affecting directly the fu 
ture course of development. Not all of us will play 
an active part in that 14th symposium. Some may even 
already be engaged in an interesting study on "ange- 
lo photogrammetry" and —although I have high hopes 
for the technological advances of the next century— 
I am strongly convinced that in that case oral pre 
sentation will be a major obstacle. 
IN RETROSPECT 
The 1962 symposium was still just in the era domi 
nated by stereoscopic interpretation of aerial 
photographs using simple conventional methods that 
had been established three or four decades earlier. 
This is clearly reflected in the papers presented: 
only five of the 75 papers of the transactions deal 
with technical and méthodologie matters, the re 
mainder being straight-forward applications to 
specific fields and areas. 
The winds of change, however, were already begin 
ning to blow and in part were also reflected in the 
programme. Airborne geophysical surveying, particu 
larly magnetometer surveys, but also EM and scin 
tillometer surveys, using low-flying aircraft had 
become common practice in the 1950s, but these non 
imaging remote sensing methods had developed inde 
pendently and had rather escaped the attention of 
photo-interpreters: There was no paper presented 
about this subject during the 1962 symposium. 
Some textbooks on photo-interpretation in those 
days already pointed to the fact that the visible 
spectrum, in which aerial photography is rooted, is 
only a small portion of the electro-magnetic spec 
trum and that other wavelengths, particularly the 
microwave and thermal IR bands, awaited explora 
tion. Although vertical PPI (plan position indica 
tor) radar had been extensively used during World 
War II, the strip-wise sensing by SLAR was develop 
ed only in the 1950s and was not yet commercially 
available in 1962. Thermographic remote sensing had 
just made its entry in the scene and although air 
borne applications were not referred to during the 
symposium, two papers dealt with early satellite 
applications of this type of sensor installed in 
the TIROS (Television and Infra-Red Observation 
Satellite) low-resolution weather satellites. These 
two papers thus also mark the advent of> satellite 
remote sensing and it is of interest to note that 
each of them highlighted a subject that is still a 
focus of interest, namely: surveillance and moni 
toring through repetitive satellite passes, and 
computer applications in semi-automatic satellite 
image interpretation systems (mentioning, for exam 
ple, pattern recognition, man-machine communication 
and the need of a (photo) data base). Obviously in 
1962 photo-interpretation was on the threshold of 
the new era of "remote sensing" that in the past 24 
years has stunned the professional world by a mush 
rooming of new tools, methods and applications.