The curved surface is usually the surface of the Earth and the plane is what we call a map. Concepts MapsĪ map projection is a procedure or mathematical formula to transform a curved surface onto a plane. Along with comments in the source code, it also describes the format of the map and grid parameter files. The purpose of this document is to give a brief introduction to mapping, gridding, and the associated terminology used in the Mapx library at NSIDC. The location is also constant, which makes it easy to compare data from different sensors or different time periods. Grids are an efficient means of storing data because the location of a value within the grid is implicit-it is not explicitly stored in the grid. Satellite remote sensing has made possible the collection of data over large areas of the Earth. Exchange for Observations and Local Knowledge of the Arctic (ELOKA).NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC).Greenland Today & Antarctic Ice Sheet Today.