Anna Jensen
Professor of Geodesy
As a science, geodesy is concerned with determining the size and shape of the earth as well as its gravitational field, and conducting geodynamic studies. This concept includes not just the earth's surface and oceans, but also, to some extent, the earth's atmosphere. Geodesy utilises satellite, aerial and ground-based instruments to determine the positions and motion of points or object on or above the earth's surface.
One of the instruments used is GPS (Global Positioning System), with new advanced algorithms and models for determining positions are constantly being developed order into achieve a higher degree of precision. This includes models of how the atmosphere affects GPS satellite signals, which is Anna Jensen's research field. In principle, these models describe how the weather (air pressure, temperature and humidity) and electric currents in the atmosphere affect the transmission of GPS signals.
These models are used for geodesic and other scientific GPS applications, but can also improve commercial use of GPS when millimetre or centimetre precision is required. Examples of Jensen's work include GPS applications for surveying, landing aeroplanes and controlling and monitoring large machines on construction sites.