Digital Archive


The archive of code and plots for VERTCON 3.0 release 20190601 is accessible through the following FTP link:

https://geodesy.noaa.gov/pub/vertcon3/20190601release/

This section provides an overview of the archive contents; specifics are available in various README files at appropriate levels in the archive itself.

The basic structure of the archive is broken into three main directories:

Builds
Final results comprising VERTCON 3.0 release 20190601.
RunVERTCON3
Code and supporting files to generate results.
AnalyzeVERTCON3
Code used for outlier identification and figure generation.

Builds

The Builds sub-directory contains all of the final transformations comprising VERTCON 3.0 release 20190601. Each transformation is contained in a subdirectory one level down, titled by od.nd.rg, in which od is the original datum, nd is the new datum, and rg is the region. Each directory contains the data files used to generate each grid, the final transformation and error grids themselves, Generic Mapping Tools (GMT) scripts used to generate plots; and other products which were derived along the way.

Each transformation has a plots subdirectory, containing all the JPG plots generated during processing. For ease of navigation, the plots are grouped into subdirectories as follows:

coverage
Location plots for data points.
vectors
Vector plots for data points, where the “vector” is formed as “new coordinate minus old coordinate.” The name “vector” is retained for parity with NADCON 5.0 release 20160901 plots, but the up/down orthometric heights are plotted using colored dots rather than arrows.
datanoise
Colored surface plots for noise introduced by variation within the data themselves.
methodnoise
Colored surface plots for error potentially introduced by the GMT surface routine and the choice of tension = 0.4.
errors
Transformation errors, which are the sum of data noise and method noise.
transformation
Colored surface plot depicting the transformation itself, with orthometric height transformations shown in meters.

* Note that only the NGVD 29 to NAVD 88 transformations for Alaska and CONUS include datanoise and methodnoise directories. The transformations in all other regions involved masking out large oceanic areas, and the authors decided to omit plots for the error estimate interim products.

RunVERTCON3

The RunVERTCON3 directory is structured so that a user can copy the full directory tree to a local machine, compile the code using the provided script, then run the code to generate VERTCON 3.0 results. The RunVERTCON3 directory contains a README file with code compilation instructions, and a number of sub-directories:

Boundaries
Boundaries of continents, islands, and states, used for drawing maps.
Code
All code needed to generate this release.
Control
Files which group realizations into regional grids.
Data
Supporting grid and boundary files for the runs.
InFiles
The fundamental data files for VERTCON 3.0.
VERTCON2
Grid files for the VERTCON2 transformation, used in the remove/compute/restore process.
Work
Contains only file “workedits”, which lists the points marked for deletion.

AnalyzeVERTCON3

The AnalyzeVERTCON3 directory contains helper programs used for user-friendly analysis of the data. These codes help map heights, identify outliers, and choose the appropriate grid size for each transformation. There are also codes in this directory to generate final transformation and error plots for regions with masked-out oceanic areas. The README file at this level gives an overview of the code.