96
February 2015
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
industry, defining its relationship with the European Union,
and reforming the investment law to allow up to 100% foreign
ownership in activities and sectors considered strategic”
(U.S.
Dept. of State Background Note, January 2007)
.
Bordered by France (55 km) (
PE&RS
, January 2001) and
Spain (63 km) (
PE&RS
, July 2000); Andorra is 2½ times the
size of Washington, D.C. The lowest point is Riu Runer (840
m), the highest point is Pic de Coma Pedrosa (2,946 m), and
the terrain is rugged mountains dissected by narrow valleys
(
World Factbook, 2015
).
The geodetic history of Andorra is intertwined with that of
Spain. The recent (65 year) history begins with the end of WWII
when the U.S. Army Map Service transformed all of the local
datums of Europe and North Africa to the European Datum of
1950 which was referenced to the International ellipsoid. The
subsequent transformation of the Spanish Net to ED50 was
based on a two-step two-dimensional Helmert transformation.
The initial step computed by the Axis (Germans) was still
on a Lambert Conformal Conic, but referenced to the Clarke
1880, which was the standard for France. That series of co-
located points that started computations in the Pyrenees
Mountains was continued into a substantial portion of the
Iberian Peninsula. After the war, the U. S. Army Map Service
decided that the best way to merge the Madrid Observatory
Datum of 1858 into the new ED50 was to use the existing
German data as an intermediate step. In computing the new
French datum values of the Spanish triangulation, use was
made of the German adjustment of 1938. Values of the New
Triangulation of France (NTF) were available for the following
11 Spanish triangulation stations: Forceral, Canigou, Licuses,
Rouge, Cabére, Maupas, Anie, Orhi, Baigura, La Rune, and
Biarritz. Computations to the Madrid Datum of 1858 were
performed by V.U.K.A. 631 (April 1943) and by Kriegskarten
und Bermessungsamt, Paris (August 1943).
Since then, the Principality has been exclusively on the
European Datum of 1950 where The UTM Grid (Zone 31) has
been in use and referenced to the International 1924 ellipsoid
where:
a
= 6,378,388 meters and the reciprocal of flattening
(
1
/
f
) = 297. In a similar type of transformation used for the
computation of ED50, the Principality has published a new
four-parameter (two-dimensional) transform
from
ED50
to
the European Terrestrial Reference System of 1989 (ETRS89)
where T
x
= –129.549 m, T
y
= –208.185 m,
μ
= 0.0000015504,
and
α
= –1.56504”. This was published effective 29 August
2007 in the Royal Decree number 1071 of 2007
(Institut
Cartografic de Catalunya, 2015)
. Furthermore, a grid-based
datum transformation system has been implemented by
the government based on the Canadian technique of NTv2,
similar (but different) to the U.S. National Geodetic Survey’s
NADCON software package.
The contents of this column reflect the views of the author, who is
responsible for the facts and accuracy of the data presented herein. The
contents do not necessarily reflect the official views or policies of the
American Society for Photogrammetry and Remote Sensing and/or the
Louisiana State University Center for GeoInformatics (C
4
G).
STAND OUT FROM THE REST
earn asprs
certification
ASPRS congratulates these recently
Certified and Re-certified individuals:
CERTIFIEDMAPPINGSCIENTISTS,
REMOTE SENSING
Jonathan Ellinger, Certification #RS224
Effective December 15, 2014, expires December 15, 2019
Joseph Racine, Certification #RS225
Effective January 10, 2015, expires January 10, 2020
CERTIFIEDPHOTOGRAMMETRIST
Jonathan Ellinger, Certification #1577
Effective December 15, 2014, expires December 15, 2019
CERTIFIEDPHOTOGRAMMETRIC TECHNOLOGIST
John B. Ong, Certification #1578PT
Effective January 1, 2015, expires January 1, 2020
THE
IMAGING & GEOSPATIAL
INFORMATION SOCIETY
ASPRS Certification validates your professional
practice and experience. It differentiates you from
others in the profession.
For more information on the ASPRS Certification
program: contact
visit
