Not Your Father's Nautical Chart

by Capt. Richard Brennan, NOAA

Your father’s nautical chart is no longer good enough. The size of the ships navigating today’s waterways has rendered them obsolete. The reduced clearances below the keel, above the mast, and laterally within the channel have forced the mariner to demand new tools to safely accomplish their passage from sea to berth efficiently and with statistical confidence. NOAA is responding to this pressing problem by developing a new generation of products and services to support the mariner’s need for precision navigation. These new products and services will enable 24x7 port operations, increase the effectiveness of both passage planning and execution, and allow easy access to NOAA’s navigational data in formats that support predictive analysis of under-keel clearances that help manage transit risks.

NOAA’s e-navigation role is to provide accurate and timely coastal intelligence to the maritime community and to deliver that information in a direct and visually stimulating method to the location where port operators and mariners make decisions. Asking maritime professionals to bookmark data sites here and there, and to carry multiple data delivery systems, is simply not sustainable. The next generation of navigational tools in an electronic environment needs to be integrated (or, at the very least, “integrate-able”) and intuitive.

So what is NOAA actually doing to get from your dad’s chart to the next generation of navigation systems?

In developing the suite of next generation navigation services, NOAA first looks to what the mariner is trying to accomplish: 1) reduce the risk of collisions, allisions, groundings and oil spills; 2) maximize cargo volume; 3) reduce shipping delays; and 4) minimize port congestion.

Figure 1:  The Precision Navigation Tool developed by NOAA was designed to demonstrate the power of coupling high resolution bathymetry with real-time water levels (tides) to dynamically portray areas where it is safe to navigate (green) based on a particular vessels draft, and where the water is too shallow (red). View this prototype at http://pnt.nauticalcharts.noaa.gov/LALB/

In a new prototype program, NOAA now provides data feeds for a navigational information system where the whole is greater than the sum of the parts (Figure 1). To begin with, the agency has a powerful trove of data, including both real-time measurements and modelled forecasts for water levels, wind, waves, currents, and water salinity. When these are coupled with high-resolution bathymetry (complete coverage depth information) and supported by a high-accuracy geodetic framework, these data can provide a simple service that informs the mariner about the statistical probability of grounding. This is further refined by the anticipated ship’s motion given the wind and wave direction, the known motion characteristics of their ship, anticipated crab angles, and the required headings needed to achieve a required “course made good” with the current meteorological conditions.

Jacobsen Pilots, in collaboration with Charta Software, is currently testing and evaluating this new suite of NOAA’s prototype products ‒ high-resolution bathymetric charts, wave models, and real-time water levels ‒ in the Port of Long Beach. They are specifically evaluating the products for integration with a new under-keel clearance management system. NOAA has also provided high-resolution chart cells in the Inland Electronic Navigational Chart IENC product format (for the Ports of Los Angeles and Long Beach) to software developers to test and analyze in their chart plotter and portable pilot unit systems (see at: nauticalcharts.noaa.gov/mcd/enc_overlays.html).  These IENC cells are used because they offer the flexibility to display higher density soundings and contours to the mariner.  Even higher resolution gridded bathymetric data is available for interested software developers. 

NOAA will carry the lessons learned in Long Beach and Los Angeles to other ports across the country. In the next three years, the agency will work with maritime stakeholders in the highest volume ports across the country including the ports of the southern Mississippi, Houston-Galveston, and New York.

Figure 2: This animated GIF demonstrates the power of vector tiles to seamlessly zoom, pan, and rotate nautical chart data and provide an increasing amount of data resolution as the user zooms in.  Image provided compliments of ESRI.

Looking a bit further out to the future, NOAA is developing new electronic chart formats that will carry even higher resolution data. The GIS industry is also developing new vector formats that are compact and easily transmitted, which will optimize the scale and content of navigation-related data used via existing cellular networks to 3G and LTE enabled mobile devices. Web-based “tiled” maps, inspired by video game technology, make it possible for mobile devices with personal GPS navigation to deliver maps with zoom and pan features (Figure 2). As these maps have begun to shift from raster images like paper charts to vector images like IENC, the underlying technologies have been enabled by the Open Source community adoption for products like OpenStreetMap. The recent open specification for vector tiles (https://github.com/mapbox/vector-tile-spec) will eventually enable all modes of use to have access to vector information in the same way we now use the raster images. This will create great opportunities for fit-for-purpose navigation information services with optimized cartography beyond anything your father could imagine in yesterday’s wheelhouse.

The next generation of navigational system products will be a boon to the maritime industry ‒ but it goes further than that. The nation will benefit from ports that are more competitive, port communities that are more resilient, and vessels that produce fewer emissions thanks to decreased idling time and optimized speed during their approach. So, the question isn't whether the nation needs next generation navigational system products. The important question is: how soon can we deliver them?

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