|A brief description of each branch follows:
Nautical Data Branch (NDB)
NDB is the front-end clearinghouse for the nautical charting process. NDB acquires and manages all data used in the compilation of nautical charts. NDB receives information, potentially affecting NOAA charts, from sources such as the U.S. Army Corps of Engineers, the U.S. Coast Guard, and other federal, state, and local government agencies. This information may be in a paper or in an electronic format. NDB logs in the information and makes a determination as to whether it may affect NOAA charts. If necessary, paper information may be scanned into an electronic format. The source information is then assigned to the appropriate chart production team for chart application.
NDB is proactive in engaging charting source providers. Communication is an important element in order to ensure that NOAA receives all information affecting its charts.
Raster Production Branches (Products Branch A, C, E – PBA, PBC, PBE)
NOAA maintains a suite of over 1000 traditional paper charts. These charts are also available in a raster (scanned) format. Each of the three raster branches is responsible for maintaining a set of charts that fall in a particular geographic area. PBA is responsible for charts covering the West Coast, Alaska, and the Great Lakes. PBC is responsible for East Coast charts, while PBE is responsible for charts in the Gulf of Mexico.
When the Nautical Data Branch receives a piece of source information, it is immediately assigned to the appropriate Products Branch for application to the affected chart. Cartographers from the raster branches immediately evaluate the source information and apply the update to the appropriate chart – or often, to multiple charts covering the same geographic area. Cartographers apply the update to master electronic versions of the latest charts using automated Computer Aided Design (CAD) tools. The process of keeping charts up to date by applying source data immediately is known as “continual maintenance.”
Some of the new information applied to the continual maintenance chart may be critical to navigation. Cartographers will generate a chart update that will ultimately be forwarded to the Coast Guard and the National Geospatial Intelligence Agency (NGA) for inclusion in a Local Notice to Mariners and U.S. Notice to Mariners.
When a new edition of a chart is to be published, cartographers review all information that has been applied since the last edition. In addition, updates received through the Local Notice to Mariners and Notice to Mariners are applied and reviewed.
ENC Branches (Product Branches B and D)
NOAA’s Electronic Navigational Chart (ENC) program began in the 1990’s. ENCs are vector charting data sets that conform to the S-57 international standard. Coast Survey began an ENC building and maintenance program in the late 1990’s that continues today. As of 2006, NOAA has built and maintains over 500 ENC cells. Coast Survey’s goal is to build a full set of ENCs that will correspond to coverage offered by the suite of 1000 paper charts.
ENCs are first “built” by taking the raster(i.e. paper) chart, and creating a vector data set. In many NOAA charts, high accuracy information about important features are embedded into the ENC. For example, if high accuracy channel limits are available, that information would be embedded into the ENC rather than vectorizing it from a small scale raster chart. Other critical features like wrecks and obstructions are transferred from highly accurate source information.
The general ENC maintenance procedure is similar to raster chart maintenance. Cartographers will review a piece of source and update the ENC as warranted. Care must be taken so that the raster chart and the corresponding ENC are consistent. In the beginning of the ENC program, ENCs were updated by using the updated raster chart. However, increasingly, ENCs are now being updated by direct application of source. This ensures that highly accurate geospatial data is embedded directly into the ENC.
Most cartographers who work in the ENC branches have prior experience in the raster branches. The cartographers possess an advanced understanding of nautical cartography. They also have the skills to utilize the sophisticated computer systems used to maintain ENCs.
Increasingly, ENCs are being updated by private contractors on and off site. NOAA cartographers perform review before new ENCs are posted on the Internet for free download.
Update Service Branch (USB)
USB is a group cartographers who apply critical chart corrections published in the Coast Guard Local Notice to Mariners (LNM) and the National Geospatial Intelligence Agency (NGA) Notice to Mariners.
Cartographers in USB are typically assigned all charts that correspond to one or more Coast Guard Districts. Each Coast Guard District publishes chart corrections in their respective LNM. Over half of these corrections originate from MCD raster branches, so NOAA already knows about these corrections. The remainder of the chart corrections originate with the Coast Guard (e.g. changes in aids to navigation) or are changes that have been reported to the USCG.
As soon as the weekly LNMs are made available, USB cartographers apply updates to the appropriate raster/paper and ENC charts. An identical process is performed with NGA’s Notice to Mariners (which mostly contains updates already reported in the Coast Guard LNM).
Once all master charts have been updated, the raster files are then made available to NOAA’s contractor, Maptech. Maptech creates geo-referenced raster chart files in .BSB format and them makes them available for NOAA to post for free download on the Internet. NOAA files are also made available to another contractor, Oceangrafix. This contractor produces Print on Demand charts.
Updated ENCs are also produced by this process.
Quality Assurance(QA), Plans and Standards Branch
This branch is composed of approximately six senior cartographers. Their job is to ensure that the overall quality of Coast Survey’s nautical charting products meets NOAA standards. The Nautical Charting Manual is Coast Survey’s primary reference document for charting standards.
Cartographers from QA branch also draft charting policy when new situations arise. Between publications of new editions of the Nautical Chart Manual, Cartographic Orders are issued that give guidance to production cartographers.
Production cartographers will often consult with members of QA in order to clarify current charting policies.
System Support Group
The System Support Group is a technical staff in MCD that is composed of approximately five computer specialists. MCD utilizes several sophisticated computer systems and databases for supporting nautical chart production. The System Support Group plays a vital role in developing, maintaining and enhancing these systems and databases.
MCD is increasingly providing customers with products that can be downloaded from the Internet. The System Support Group develops web applications and databases that help enable these activities.