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The Coast Guard Electronic Charting Guidance Team (ECGT) recently provided the impetus for the Coast Guard to enter into a partnership with NOAA for the co-production of electronic navigational charts (ENCs), and the sharing of critical data between the agencies. An interagency memorandum of agreement (MOA) will formalize this effort.

Electronic vs. Paper Navigation

The Coast Guard has been exploiting electronic navigation systems for many years, providing opportunities for increased efficiencies both in the existing fleet and several classes of replacement cutters and boats. While these systems use high tech hardware and software, a key component of these systems is the "fuel" they use. This "fuel" is the electronic database from which the chart display is derived. Coupled with radionavigation input from LORAN, GPS, and DGPS, electronic chart systems significantly improve safety of navigation. In simple terms, it is much safer to know where you are right now (electronic navigation - one person evaluating an electronic display - and little chance of human error), than where you were 3 minutes ago (traditional paper chart navigation using a large navigation team).

Electronic Navigational Chart Production

In the world of electronic charts, there are many different data formats and producers. The Coast Guard currently uses several types of electronic charts, the majority of which are not official NOAA products. Until now, because there is no official coverage of US waters, Coast Guard has been paying for the production of some of this unofficial data. The Coast Guard and NOAA recently came to an agreement to ensure that charts already produced, and future chart production by either agency, will end in official products available free of charge to the CG and the public.

Data Sharing

Many changes to NOAA charts come from Coast Guard Local Notices to Mariners (LNM). Traditionally, each CG District office issues their LNM on a weekly basis. Chart and Light List corrections are derived from the Aids to Navigation Information System (ATONIS), and are distributed by mail (both electronic and snail) and on NAVCEN's website. Currently, manual data reentry is required at several steps in this delivery process. With the advent of electronic charts and the increasingly austere budget climate, this out-dated, labor-intensive way of doing business is no longer sufficient.

Along with ATONIS, there are two other US Government AtoN databases: the Coast Guard Light Lists (which reside on a NIMA server), and NOAA's own internal AtoN database. These databases are isolated from each other, and their information is stored in different formats. As a result, the information each contains differs from the others. This issue of data quality is another major work item under the MOA. Someday soon, the information common to all three databases will be of higher quality, and correlated to each other. The ECGT Data Sharing Working Group held its first meeting at NAVCEN on April 11th to begin addressing these issues.