| 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. Back |
