In November 2013, we introduced NOAA ENC Online – a continuous viewer for our electronic navigational charts. You can click on the web map and zoom to selected features or locations, to see the information contained in over a thousand electronic charts of NOAA-charted waters. Each zoom moves you through an ENC depiction that takes into account the ENC scale and other attributes that are encoded in the ENC, allowing features to become visible or invisible as you seamlessly zoom in and out of the data.
NOAA ENC Online is based on Esri’s Maritime Chart Server.
Now this latest release of NOAA ENC Online lets you:
- Set a shallow and deep depth contour, which changes the shading to those parameters
- Set a safety contour (In electronic charting systems, the safety contour is set based on the ship’s draft changes the depiction of rocks, wrecks and obstructions to isolated dangers depending on if the water is “safe” or “unsafe” for vessel navigation.)
- Change between S-52 simplified and S-52 traditional symbols
- Change the background colors of the display based on the S-52 color palette for different light conditions on the bridge of a ship
- Turn off certain features based on different categories such as buoys and traffic routes
NOAA ENC Online is not certified for navigation. It does NOT fulfill chart carriage requirements for regulated commercial vessels under Titles 33 and 46 of the Code of Federal Regulations.
by Meredith Westington, Coast Survey geographer
Good, informed decisions are often based on analyses of historic and present conditions. Researchers, decision-makers, and amateur history buffs find detailed documentation of past conditions in the thousands of Coast Survey charts, dating back to the mid-1800s, in our Historical Map and Chart Collection.
Just like present day nautical charts, historic charts contain a wealth of information about geographic features — including their names, shape, and condition. Geographic names are important locational references for today’s emergency responders, but current and historic names also convey important aspects of local people and culture, which may persist through time.
As Coast Survey’s nautical cartographers routinely apply new topographic and hydrographic data to improve decisions at-sea, a question arises about names when a geographic feature, such as an island, bay, or bayou, has changed: does the associated place name disappear when the geographic feature is no longer there, or does the local population still use the historic name to convey a shared sense of place?
Coast Survey cartographers raised this exact question after applying new shoreline information to charts covering Louisiana. When cartographers applied new shoreline data to charts 11358 and 11364 in 2011, they found that named features were no longer there (see the images below for a comparison of today’s landforms vs. the historic landforms in 1965). In early 2013, another new shoreline survey similarly affected fourteen geographic names on chart 11361. They removed these “dangling names” to reduce chart clutter, but are there new names for the areas where the features used to be?
Losing places (and their names) may mean losing important locational references. Some of these places have appeared on NOAA’s nautical charts of Louisiana since the late 1800s, so their removal raises concerns about a loss of cultural identity on the landscape. For example, Cyprien Bay was named for longtime resident Cyprien Buras. The names live on, of course, on the historic maps and charts in Coast Survey’s Historical Map and Chart Collection. Importantly, they are also retained in the lesser-known U.S. Board on Geographic Names’ federal repository of place names, the Geographic Names Information System. The system’s current and historical records make a great starting point for finding names that you can use to locate relevant historical nautical charts in the Historical Map and Chart Collection. The collection has an easy-to-use geographic place name search function. Just type in a name, and start to explore our nation’s geographic changes…
Search over 35,000 historical maps and charts, just using a geographical name.