European
Funding and Digital Mapping Expand Use of GeoTechnologies
in Ireland
By Kevin P. Corbley
Development and
implementation of the GeoTechnologies in the Republic of
Ireland have generally lagged behind the rest of Western
Europe. In the last few years, however, the Emerald Isle
has become increasingly more involved in remote sensing,
digital mapping and GIS. This sudden growth is due in part
to initiation of a major digital mapping program by the
Irish government and investiture in several land survey
projects by the European Union (EU).
GIS use has not caught in
Ireland the way it has in many other parts of the world
primarily because up-to-date, digital topographic maps
have not been available, according to Paul Mills of
Geographical and Multi-Media Applications Ltd. in Dublin.
He sees this trend about to reverse thanks to a recent
initiative on the part of the government.
The lack of modern maps has
not gone unnoticed by the Irish government which has
tasked its national mapping agency, known as the Ordnance
Survey, to create new digital maps for the entire 27,000
square miles that comprise the Republic. The re-mapping
will involve aerial photography and photogrammetry and is
expected to take 10 years to complete.
Ireland's frequent cloud
cover has almost certainly been a contributing factor that
has limited use of satellite imagery on the island itself,
but several remote sensing organizations have managed to
establish themselves in Dublin and are now engaged in
projects around the world. In fact, if it weren't for
several mapping projects initiated by the European Union,
of which Ireland is a participant, the vast majority of
GeoTechnology business received by these Irish
organizations would come from other countries.
The Major Players
ERA-MAPTEC Ltd., a full-service remote sensing, digital
mapping and GIS consulting firm in Dublin, has emerged as
a leading international GeoTechnology company. It grew out
of a consulting group formed in 1983 within the geography
department of Dublin's Trinity College. The company now
employs more than 30 people in several worldwide locations
including Japan and Australia.
ERA-Maptec applies Landsat,
SPOT and ERS-1 radar data to a variety of monitoring and
mapping projects in environmental and hydrologic fields.
Geologic mapping, however, is the firm's specialty. Most
of its remote sensing analysis is conducted to create
structural maps and terrain models for application in
mineral and petroleum exploration. It has active projects
in Eastern and Western Europe as well as Australia, Mexico
and Chile.
The in-house laboratory is
equipped with a variety of hardware platforms, digitizing
workstations and printers. Technicians perform nearly all
satellite image processing, including analysis, DTM
generation, and orthorectification, using ERDAS Imagine
software. Digital image data is ported to ARC/Info for
integration with other geographic data and to J Map
software for hardcopy output.
Geographical and
Multi-Media Applications Ltd., or Gamma, is a broad-based
GIS consulting company that has found a niche in the
rapidly emerging field of business geographics. For its
private sector clients, 75 percent of which are in
Ireland, Gamma focuses on using remote sensing and GIS
technology for planning, census, demographic and marketing
applications. Gamma's other private sector clients are
located in Western Europe.
The private company also
holds several contracts from the Irish government and from
the Commission of the European Union. The projects involve
agricultural monitoring and mine rehabilitation.
Gamma conducts most of its
database development work with ARC/INFO GIS software and
the MapInfo desktop mapping package. The company has also
developed several customized software programs of its own
for business geographic applications.
Although it has yet to
become involved with satellite remote sensing, the
Ordnance Survey is Ireland's major supplier of digital and
hardcopy maps. By its mandate, the Survey provides maps to
major utilities, local councils, government agencies and
private sector customers, both nationally and
internationally, according to M.J. Cory, the Ordnance
Survey's manager of data collection.
The national re-surveying
effort is the agency's main priority. It involves
conducting aerial surveys to establish a large-scale
digital database capable of map outputs at scales ranging
from 1:500 to 1:10,000. In addition, the Survey has
scanned its entire archive of existing large-scale maps
for inclusion in a seamless digital database. A SYSDECO
TELLUS software system running on DEC workstations has
been purchased to manage this database.
Cory said the Survey is
also building a small-scale database with elevation
information suitable for creating topographic maps with
10-meter contours. The agency uses the autocorrelation
technique to create digital terrain models. Elevation
points are extracted with Leica/Helava digital
photogrammetric workstations. The database is stored on a
SYSDECO VMS mapping system, and map output occurs on a
Barco publishing system with an IRIS inkjet plotter.
Trinity College takes
credit for the start of another Irish GeoTechnology
organization: the Natural Resources Development Centre (NRDC).
As a university-based research center, NRDC focuses on
environmental applications of remote sensing and GIS for
government and EU projects. Its researchers concentrate
their studies on mapping topography, groundwater and
coastal ecosystems with Landsat, SPOT and radar imagery.
The NRDC uses nearly all
major image processing and GIS packages, including
ARC/INFO, PCI's EASI/PACE, Spans, Intergraph's MGE/Microstation
and IDRISI.
Major Projects
The Commission of the European Union funded and directed
the two largest remote sensing projects undertaken in
Ireland over the past two years. Both were land-use
mapping programs that will assist the EU in determining
how financial subsidies should be doled out.
In 1992, the EU awarded a
contract under its CORINE program to ERA-Maptec and a
group of other Irish organizations to create a detailed
digital land cover classification map of the entire
Republic. Similar CORINE land cover maps were made by
various organizations for all EU member countries.
The company classified nine
cloud-free Landsat Thematic Mapper scenes using standard
clustering algorithms in ERDAS Imagine. The classification
resulted in a total of 36 land cover classes including
detailed clustering of urban areas, forests, arable lands,
crop types, pastures, bogs and coastal zones, according to
Paul Kidney, ERA-Maptec's marketing director.
The EU created the CORINE
land inventory to define which areas should be granted
"disadvantaged" status because of land unfit for
agriculture, grazing or other productive activities. Based
on this information, the EU awards subsidies to land
owners in the disadvantaged areas.
ERA-Maptec and Gamma are
both involved in the second EU mapping project, which is
the largest remote sensing project ongoing in the country.
Its objective is to verify that Irish farmers are
complying with the restrictions of EU's farm subsidy
program.
The EU controls food prices
artificially in the European Community by regulating the
supply of various crops. The EU accomplishes this by
buying up large amounts of crops and paying farmers not to
grow crops in a certain percentage of their fields.
The farmers submit reports
and sketch maps showing the type and acreage of crops
planted in their fields each season and the acreage of
land set aside for non-planting. ERA-Maptec is digitizing
the farmers' maps for inclusion in a GIS. These maps are
then compared to classified Landsat and SPOT satellite
imagery on the database to ensure that the farmer is
growing or not growing what he claims, said Gamma's Paul
Mills. Similar projects are underway in other EU states.
Private Sector Projects
Private sector GeoTechnology applications include two
projects recently initiated, one by ERA-Maptec and the
other by NRDC. The ERA-Maptec project focuses on
exploration for copper and other economic mineral sources
within the Sredna Gora metallogenic zone in central
Bulgaria.
The company has merged
Landsat TM with SPOT panchromatic imagery to highlight the
hydrothermal alteration zones and geologic structure of
the region, said Derek O'Carroll of ERA-Maptec. The copper
bearing bodies are expected to be discovered in favorable
fault structures with evidence of hydroxle and iron
minerals related to porphyry hydrothermal alteration, most
likely near Upper Cretaceous intrusions.
Principal component
analysis isolated the anomalous signatures believed to be
related to the alteration. High-resolution SPOT imagery
was used to isolate and remove anomalies caused by urban
features. The Landsat thermal band was employed to
discriminate sedimentary volcanic rock from the igneous
plutons and fault zones, explained O'Carroll.
ERA-Maptec created thematic
maps of the region's geologic structure and lithology for
input into a GIS. There the image-derived data was
correlated with geologic data from existing mines and
other ground truth information. Several potential mine
sites have been selected using this multiple-data
approach, said O'Carroll.
In an entirely different
type of application, the NRDC is collaborating with the
Department of Electrical Engineering and Microelectronics
at Trinity College to develop a radio propagation model
that will be used to establish a cellular phone network in
Ireland.
Cellular networks are
comprised of transmitters and antennas spread across the
coverage area. The placement and distance between the
antennae is determined by standard radio wave propagation
models that take into account land cover and topography.
The NRDC has developed a DTM for the country and is
creating a land-cover database using synthetic aperture
radar imagery. This information will determine how the
network should be laid out for maximum efficiency and
minimum cost.
About the Author:
Kevin P. Corbley is director of Corbley
Communications, which provides PR and marketing services
to remote sensing, GIS and GPS firms. He is located in
Denver, Colo.
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