Ohio State University scientists, aiming to correct GPS errors have created software which would measure accurately the altitude of mountainous regions.
The initial tests have been carried out for the software, and the results indicate that it is possible to conduct GPS positioning at the centimeter-scale for almost 97% of the time. This software would help taking accurate measurements in landslide areas too.
According to Dorota Grejner-Brzezinska, who is a Professor of Environmental and Civil Engineering at Ohio State University, GPS was mostly recognized for its ability for giving instant locations for drivers and now the added dimension of altitude enhanced it a great deal for the drivers. This would also help in identifying tiny shifts in the topsoil which might cause landslides.
The data is transmitted in the form of radio waves to the user held GPS receiver and other receivers used as reference. The signals need to travel via the atmosphere of the Earth, which would lead to time delays and thus affect accuracy. There are also more delays when the reference and user receivers are positioned at different altitudes, causing problems in optimizing the altitude of the places to within a few centimeters. She and her team members found that temperature, weather and height difference between two stations contributed to the accuracy of a GPS based height system. With a number of experiments carried out at different heights in the Carpathian Mountains in Poland, they gathered GPS data by utilizing special software and applied three varied techniques for measuring GPS accuracy for the receivers. Finally one method which involved using three or four reference stations showed results that were accurate 97% of the time. There is also a plan to carry out further testing.
Source: https://www.osu.edu/