Submitted by the Men’s Breakfast
Pat Hills, a Cape Hurd summer resident, provided a well-received presentation on geographic locating and measuring known as “Geomatics”. Pat’s career covered 40 years in the legal survey and mapping field and, post-1993, in geographic measuring and software. The latter in sales and technical support as a partner in CANsel, a location and mapping provider. He currently provides volunteer services to the Bruce Trail Association’s Peninsula Club as well as for a hostel in Guelph.
Geomatics is an earth science, defined as “the measurement and representation of the earth and it’s gravities in scale, time and varying space”. Its disciplines include GIS (Geographic Information Systems/digital mapping); topographic surveying (think bridges and dam construction and monitoring); construction (including back-casting of historical structures for modern modifications); geodesy (shape of the earth and crustal movements); and lidar (laser mapping) including the documentation of historical properties for future reference (think Ukraine).
Over time, improvements of earth measuring devices has evolved from approximately 50km accuracy (the sextant) to today’s mm accuracy via satellite-based GPS (Ground Positioning Systems) hand-held devices, including your phone! GPS was first conceptualized in the 1960’s during the cold war for military purposes. In 1983 President Ronald Reagan opened satellite access to civilian use following the shooting-down of a civilian airliner (Korean Air flight 007) by the Soviet Union. Full public access was subsequently made available by Bill Clinton; now anyone can purchase a GPS device or download positioning apps on their phone.
GPS devices work by trilateration (triangulation) whereby locational signals from 3 or more satellites are obtained by your device defining your position either in longitude/latitude or UTM (Universal Transverse Mercator projection)) which is based on a metric grid covering the entire earth. Although now potentially accurate in sub-millimeters, errors are created by solar flares; obstructions (building/trees); satellite geometry; and quality of your receiver. These tools have provided us with incredible capabilities in spatial knowledge (i.e., search and rescue, outdoor recreation, natural resource development, construction and monitoring, navigation, and so on.
The next Men’s Breakfast will be Saturday July 12th, at the Tobermory Community Centre. Breakfast is at 9:00, coffee ready at 8:00. Please contact Steve at mensbreakfastnsbp@gmail.com if you are planning to attend.
