Documentation

The Glacier RePhoto Project Documentation

Database Description

This project stores records of glacier rephoto stations, glacier rephoto images, and image metadata within a geospatial database. The database contains two tables. The photo station table stores information on the location, establishment, and image summary statistics on image count and the date when the station was last occupied. Image metadata, stored in a second table, includes information on the photographer, date, and observations on glacier conditions and changes from previous images. Glacier rephoto images are stored separately at multiple levels of post-processing. A low resolution image is stored as an attachment to the image metadata table. A one-to-many relationship is maintained between the photo stations and the image metadata tables.

Table Metadata

Field data types and definitions are provided below for the station and photo metadata tables.

Rephoto Table Metadata

Image Permission Levels

Images are assigned three permission levels: public, protect, and restricted. Each permission level defines how the image can be used by The Glacier Rephoto Project and the public. The photographer maintains the copyright on their images at all three permission levels.


Public: Permission is granted to The Glacier Rephoto Project to publish on the web or print at full resolution and distribute to public requests with proper citation of photographer and/or source.


Protect: Permission is limited to the display of the image on the web to a resolution of 1600 pixels on the long edge of the image. Lower allowable resolutions are available on request. The photographer and/or source must be contacted prior to using the image in any way outside of this project.


Restrict: Permission is restricted to storage of an archive copy only and will be used for research purposes only. Requests for publishing will be referred to the photographer and/or source.

Image Post-Processing

Raw images are stored as received at an archive level. Images are processed to Level 1a and Level 2a upon request or for research purposes. Secondary processing (b) places the year and photographer’s name.

Raw: Original image as photographed or scanned. Image is stored in the archive.

Level 1a: Image color, contrast, and orientation adjusted. Image is aligned by frame and scale to the origin image. Corrections applied for varying focal lengths.

Level 1b: Aligned image (1a) is stamped with year and photographer’s name.

Level 2a: Aligned images (1a) are placed side-by-side into a single paired image or image series.

Level 2b: Paired image (2a) is stamped with year and photographers’ name

Image File Naming Convention

Level 1. Individual images files are named using the glacier name, station name, and year the image was acquired, separated by an underscore. All lower case. glacier_station_year example: nisqually_5_1964


Level 2. Paired images or image series files are named using the same convention with additional image years added at the end in sequential order, separated by an underscore. glacier_station_year1_year2 example: nisqually_5_1964_1974_2015