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The Evolution of the Ice Edge Message at the National Ice Center

One of the first signs of emerging computer technology at the National Ice Center (NIC) occurred when the NIC purchased its first personal computer (PC) in 1984.  Initially used only for basic word processing, NIC analysts soon recognized the value of the computer in daily operations.

An example of a digitizing board

An example of a digitizing board, similar to the ones used at the NIC.

For years, the NIC has produced ice edge messages, which consist of a series of latitude/longitude points that, when put together, form a line representing the extent of ice cover in a given region.  Prior to the advent of the PC, these messages were typically hand-written by analysts and sent using teletype.  However, as the NIC began using computers in its daily operations, messages were constructed on a PC. 

Soon after incorporating the PC into its day-to-day operations, the NIC purchased its first digitizing board.  When paired with a PC, this board could be used to manually digitize (trace) the ice edge and create a digital message.

An ice edge could be digitized by taping an analysis chart to a digitizing board, picking points to geo-rectify the board, and using a puck to manually click latitude/longitude points.  The latitude/longitude points were then saved into a message file on the computer, and an ice edge message was created.  Although this process is fairly common-place now, it was a major technological step forward at the time, and it was only the beginning of many more technological improvements to come.

Today, NIC analysts produce a daily ice edge product for both the Northern and Southern hemispheres.  This product is produced entirely within a digital environment, using powerful computer workstations equipped with the latest analysis technology.  As an analyst draws lines on satellite imagery using a computer, latitude/longitude points along the ice edge line are recorded in a message format.  In addition to the message product, a graphical ice edge product is produced.  Both products are made available to customers on the NIC Web site at