NOAA Nautical Charts

Identification Information

Citation Information

Originator	MDEP
Publication Date	2001
Publication Time	Unknown
Title	NOAA Nautical Charts
Geospatial Data Presentation Form	tabular digital data

Abstract

This image catalog shows the NOAA nautical charts for any given area. Like other image catalogs, it is really just a pointer to the chart images stored in z:\images. These NOAA charts are converted from the MapTech BSB format.

Purpose

To plot NOAA charts on maps.

[langdata]

English

Time Period of Content

Calendar Date	2001
Currentness Reference	publication date

Status

Progress	Complete
Maintenance and Update Frequency	As needed

Bounding Coordinates

West Bounding Coordinate	-71.0
East Bounding Coordinate	-66.5
North Bounding Coordinate	45.5
South Bounding Coordinate	42.5

Keywords

Theme	ImageryBaseMapsEarthCover (ISO Keyword Thesaurus-Theme)

Native Data Set Environment

Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.3.1.1850

[ModDate]

20100331

[ModTime]

12090200

Metadata Reference Information

Metadata Date

20100331

[Sync]

TRUE

Metadata Contact

Contact Organization	Maine DEP GIS Unit
Contact Position	GIS Manager
Address Type	mailing address
Address	State House Station #17
City	Augusta
State or Province	Maine
Postal Code	04333
Country	USA

Metadata Standard Name

FGDC Content Standards for Digital Geospatial Metadata

Metadata Time Convention

local time

Metadata Access Constraints

none

Metadata Use Constraints

none

[mdDateSt]

20100331

[Sync]

TRUE

Contact Person

Michael Smith

Contact Organization

Maine Office of GIS

Contact Position

State GIS Manager

Address Type

mailing address

Address

State House Station #174

City

Augusta

State or Province

Maine

Postal Code

04333

Country

USA

Contact Voice Telephone

207-215-5530

Contact Electronic Mail Address

michael.smith@maine.gov

Process Description

Methods for conversion of NOAA nautical charts to TIFF images Overview - the basic process was to convert the BSB charts from MapTech into ArcInfo grids using the ChartViewer extension from NOAA and Spatial Analyst extension from ESRI in ArcView 3.2a. The grids were then reprojected to UTM, borders were clipped, and colors were matched before converting to TIFFS. Three sets of TIFFs were made, the unclipped charts in UTM NAD83, the clipped charts in UTM NAD83, and the clipped charts in UTM NAD27 (for the Coast Guard). DETAILS Conversion - We got the newest BSB-format NOAA charts from MapTech, Edition 3.0, Region 2 (Block Island, RI to Canadian border). I copied these to a local drive on the Dell server. I then downloaded the BSB ChartViewer extension from NOAA's website: http://www.csc.noaa.gov/products/chartview/ and installed in on the Dell server, which was running ArcView 3.2a. I also installed ESRI's Spatial Analyst 1.1. on this server. Then, for each of the 58 charts in Maine waters, I added it to ArcView with the ChartViewer and saved it as a grid with Spatial Analyst. Projection - As I converted each chart, I checked to ensure they all had a consistent projection system. This was for the most part true, all were in a Mercator projection. However, the latitude of true scale varied between charts based on their location. I recorded each chart's latitude of true scale, and then coded an AML to run through and define each chart's projection in its corresponding grid. Then, I coded another AML to go through and reproject each grid to UTM with the following projection parameters: projection utm zone 19 units meters datum nad83 spheroid grs80 For the record, the Mercator projection used with these charts was based on the NAD83/WGS84 datum. A second set of grids was created with the same UTM parameters above, except datum nad27, spheroid clarke1866. Clipping - Once I had a complete set of charts as UTM grids, I coded an AML to run through each grid, clip it to the boundaries of the chart, and convert any NODATA cells to values of 2 (white). This operation was: grids_clip_83\g%quad% = con(isnull(selectpolygon(grids_utm\g%quad%, tempcov, / inside)), 2, selectpolygon(grids_utm\g%quad%, tempcov, inside)) The boundaries of each chart were taken from an ArcInfo coverage, which was on-screen digitized using the charts themselves. The coverage from the earlier charts was not used because it didn't line up. Also, the dates of the charts were added to this coverage. An export file (.e00) of this coverage is on the CD-ROM(s). Colormapping - I found that most charts had inconsistent color maps. The result was that I had to go through each chart and create an individual color map. I first recorded a consistent set of colors to be used in all charts, then checked each chart's grid in ArcMap to see what values related to the various features. The colors used are: Feature Color R G B Comment Text Black 0 0 0 Open water White 255 255 255 Coastal water Light Blue 215 225 235 Mid-water Lighter Blue 240 245 255 Not on all charts Land Khaki 240 220 190 Towns Darkest Khaki 175 160 130 Only on Canadian charts Intertidal Olive 200 200 175 Navigational Purple 175 105 235 Green buoys Forest Green 70 160 0 Bathymetry Aqua 0 205 255 On most charts, also Loran "W" Bathymetry 70% Gray 80 80 80 On few charts Shipping lanes Pink 240 195 255 On small-scale charts Boundary water 30% Gray 180 180 180 International water boundary Canada charts Medium Khaki 190 175 145 Only on Canadian charts Regulatory area Steel Blue 100 180 255 NWR's, parks, etc. Cleared areas Pale Green 200 255 215 Casco Bay charts Loran "Y" 50% Gray 110 110 110 On small-scale charts Colormap files were created for each grid with the appropriate RGB values, then converted to TIFFs. The .cmp files are on the CD-ROM(s). Conversion - All grids were then converted to TIFFs using the Arc GRIDIMAGE command, with the appropriate .cmp file, and compressed with packbits compression. LZW was not used so that the images could be utilized in ArcView (which doesn't support LZW compression). CD-ROM - The TIFF images, along with supporting files, were written to CD-ROM by the GIS Unit. Three sets were created - unclipped images in UTM NAD83, clipped images in UTM NAD83, and clipped images in UTM NAD27.

Process Date

20001220

Contact Person

Michael Smith

Contact Organization

Maine Office of GIS

Contact Position

State GIS Manager

Address Type

mailing address

Address

State House Station #174

City

Augusta

State or Province

Maine

Postal Code

04333

Country

USA

Contact Voice Telephone

207-215-5530

Contact Facsimile Telephone

207-624-3842

Contact Electronic Mail Address

michael.smith at maine.gov

Process Description

To create a catalog of the converted TIFF images, I wrote an AML to loop through all the images, capture their extent using [SHOW MAPEXTENT], and write that to a text file.The text file was converted to DBF in Excel, and imported into SDE as this catalog.

Process Date

2000

Attribute Label

NOAA_Nautical_Chart_Catalog

Attribute Definition

Attribute table

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

IMAGE

Attribute Definition

Actual location of the image

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

XMIN

Attribute Definition

minimum x coordinate of the image

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

YMIN

Attribute Definition

minimum y coordinate of the image

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

XMAX

Attribute Definition

maximum x coordinate for the image

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

YMAX

Attribute Definition

maximum y coordinate for the image

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Attribute Label

OBJECTID

Attribute Definition

Internal SDE ID

Attribute Definition Source

ESRI

Beginning Date of Attribute Values

Grid Coordinate System Name

Universal Transverse Mercator

UTM Zone Number

Planar Coordinate Encoding Method

coordinate pair

Planar Distance Units

meters

Horizontal Datum Name

North American Datum of 1983

Ellipsoid Name

Geodetic Reference System 80

Network Resource Name

http://www.maine.gov/geolib/wms.htm

[accinstr]

The Maine Office of GIS and the GeoLibrary Board provide web mapping services to distribute aerial photos and other digital data. A WMS is not a web application which you can see in a web browser; rather, it requires you to add the service to a GIS software application.