AMBAPO: ENGINEERING AN OPEN SOURCE SOFTWARE APPLICATION, LIBRARY, AND WEB SERVICE FOR COORDINATE SYSTEM CONVERSIONS

Several software solutions exist for converting among the geodetic datum for latitude and longitude coordinates and Universal Transverse Mercator (UTM) easting and northing calculations. However, they are not generally user-friendly, easily adapted, or open source. Ambapo is an open source, user-friendly application, library, and web service developed as part of CIRDLES.org that provides single and bulk conversions among datum, using Charles F.F. Karney’s formulas for exact mapping of the Earth. One anticipated use of Ambapo is the conversion of lat-longs during the upload of metadata to SESAR (System for Earth-Sample Registration), which requires the datum WGS84. Ambapo differs from other similar projects with its use of the Java programming language’s BigDecimal class in order to obtain high-precision results and provides for bulk conversions of CSV (comma separated values) files. Overall, it ensures that locational data of geological samples shared among users is accurately derived.

Earth scientists have developed geodetic datum, known geographic shapes of Earth, to create mappings of coordinate systems. There are two types of referencing datum: local and global. Local datum references a set local area while global datum places its reference point at the center of Earth. Latitude and longitude are measurements of the Geographic Coordinate System with units in either degrees, minutes, and seconds or degree decimal minutes. UTM uses a Cartesian coordinate system to locate points on Earth’s surface as a conformal projection. These projections are represented by an easting and northing in meters with a zone letter and a zone number. In this system, the Earth divides into 60 vertical zones and 20 horizontal zones. Whether an earth scientist uses UTM or latitude and longitude to log coordinates, the scientist can choose a specific geodetic datum as a reference point for the location. Ambapo has been designed and engineered using modern software engineering practices, such as test-driven development and represents another important collaboration between computer science and earth science. Ambapo is hosted at https://github.com/CIRDLES/Ambapo.