Archival and Discovery of April 1, 1946 Tsunami Event on Marigrams

browse graphicDigitized marigram from Ayukawa, Japan, 1946-04-01
NOAA National Centers for Environmental Information have more than 3,000 tsunami marigram (tide gauge) records in both image and paper format. The majority of these tsunami marigram records were scanned to high-resolution digital tiff images during the NOAA Climate Data Modernization Program (CDMP). There still remain shelves full of deteriorating paper records that are in need of rescue reformatting to scanned images before they are lost. The 1946 tsunami is one of four 20th century tsunami events which are historically important but data during each reside only on the marigram records. The 1946 tsunami was the impetus for establishment of the Pacific Tsunami Warning Center after impact to the Hawaiian Islands. The 1952, 1960, and 1964 tsunamis were each generated by three of the greatest of all recorded earthquakes. The 1960 tsunami, in particular, was generated by the largest earthquake ever recorded, a magnitude 9.5 off the central coast of Chile. Measurements of these tsunamis are expected to provide researchers with important information linking earthquake rupture to tsunami generation and propagation characteristics. All data reformatted as part of this project will be brought into compliance with NOAA Data Directives and meet the requirements for Data Management, Discoverability, Accessibility, Documentation, Readability, and Data Preservation and Stewardship as per the Big Earth Data Initiative (BEDI). BEDI is designed to promote interoperability of Earth observation data across Federal agencies, systems and platforms through the improvement of data management practices and increased discoverability, accessibility, and usability of data collections.
  • Cite as: NOAA National Centers for Environmental Information; NOAA Center for Tsunami Research (2017): Archival and Discovery of April 1, 1946 Tsunami Event on Marigrams. NOAA National Centers for Environmental Information. doi:10.7289/V598856F [access date]
gov.noaa.ngdc.mgg.hazards:19460401marigram
Download Data
Distribution Formats
  • netCDF(Version:4)
    • File Specification: Unidata's Network Common Data Form (netCDF)
  • csv
    • File Specification: Comma Separated Values file (csv)
    • File Compression: GZIP
  • TIFF
    • File Specification: Tagged Image File Format (TIFF)
    • File Compression: ZIP
Distributor DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information
haz.info@noaa.gov
Dataset Point of Contact DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information
haz.info@noaa.gov
Coverage Description Coastal Tide Gauge Network of the International Community
Time Period 1946-04-01T00:02:38Z to 1946-04-04T00:46:04Z (time duration: P0Y0M3DT0H43M42S)
Spatial Bounding Box Coordinates
West:145.583333
East:-123.3707
South:35.017222
North:48.424666
Spatial Coverage Map
Associated Resources
  • NGDC/WDS Global Historical Tsunami Database
  • Marigrams recording tsunamis generated by the April 1, 1946 earthquake
  • Big Earth Data Initiative (BEDI): Archival and Discovery of 1946, 1952, 1960, 1964 Tsunami Events on Marigrams
Publication Dates
  • creation: 2017-06-01
Dataset Progress Status Complete - production of the data has been completed
Data Update Frequency Data update frequency not available
Purpose To enable archive and discovery of segments of marigram records on which are recorded sea level measurements of the April 1, 1946 tsunami originating from a magnitude 8.6 earthquake at Unimak Island, Alaska.
Dataset Citation
  • Cite as: NOAA National Centers for Environmental Information; NOAA Center for Tsunami Research (2017): Archival and Discovery of April 1, 1946 Tsunami Event on Marigrams. NOAA National Centers for Environmental Information. doi:10.7289/V598856F [access date]
Originators
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information
  • DOC/NOAA/OAR/PMEL/NCTR > NOAA Center for Tsunami Research, Pacific Marine Environmental Laboratory
Publishers
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information
Theme keywords Global Change Master Directory (GCMD) Science Keywords
  • Earth Science > Oceans > Tides
  • Earth Science > Oceans > Tides > Tidal Currents
  • Earth Science > Oceans > Tides > Tidal Heights
  • Earth Science > Oceans > Tides > Tidal Range
  • Earth Science > Oceans > Ocean Waves > Tsunamis
  • Earth Science > Oceans > Coastal Processes > Tidal Height
  • Earth Science > Oceans > Coastal Processes > Sea Surface Height
  • Earth Science > Human Dimensions > Natural Hazards > Tsunamis
  • Earth Science > Human Dimensions > Natural Hazards > Earthquakes
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information
Platform keywords Global Change Master Directory (GCMD) Platform Keywords
  • In Situ Land-Based Platforms > Ocean Platform/Ocean Stations > Coastal Stations
Instrument keywords Global Change Master Directory (GCMD) Instrument Keywords
  • In Situ/Laboratory Instruments > Gauges > Tide Gauges
Place keywords Global Change Master Directory (GCMD) Location Keywords
  • Continent > Asia > Eastern Asia > Japan
  • Ocean > Pacific Ocean
  • Continent > North America > Canada > British Columbia
None
  • Ayukawa
None
  • Hachinohe
None
  • Hakodate
None
  • Hanasaki
None
  • Miyako Harbor
None
  • Uchiura
None
  • Victoria
None
  • Vancouver Island
None
  • Strait of Juan de Fuca
Project keywords Global Change Master Directory (GCMD) Project Keywords
  • ICSU-WDS > International Council for Science - World Data System
None
  • Big Earth Data Initiative (BEDI)
None
  • Climate Data Modernization Program (CDMP)
Use Constraints
  • Cite as: NOAA National Centers for Environmental Information; NOAA Center for Tsunami Research (2017): Archival and Discovery of April 1, 1946 Tsunami Event on Marigrams. NOAA National Centers for Environmental Information. doi:10.7289/V598856F [access date]
  • Use Constraints: Public domain data from the National Centers for Environmental Information (NCEI), an agency of the National Oceanic and Atmospheric Administration (NOAA), are freely redistributable with proper metadata and source attribution. Please recognize NCEI as the source of these data. You are not permitted to use NCEI's name or to suggest that NCEI endorses your project or product, without its express written consent. While efforts have been made to ensure that these data are accurate and reliable within the state of the art, NCEI cannot assume liability for any damages or misrepresentation caused by any inaccuracies in the data or as a result of changes to the data caused by system transfers. The user must be aware of data conditions and bear responsibility for the appropriate use of these data with respect to possible errors, original drawing scale, collection methodology, currency of data, and other conditions specific to these data. Distribution Liability: Although every effort has been made to ensure the accuracy of these data, errors and conditions originating from physical sources used to develop these data may be reflected in the data supplied. The client must be aware of data conditions and bear responsibility for the appropriate use of the information with respect to possible errors, original drawing scale, collection methodology, currency of data, and other conditions specific to certain data. In no event shall NCEI be liable for any damages, whether general, special, incidental or consequential damages, arising out of your use of these data. Your sole remedy for damages is to stop using the data. You agree to defend, indemnify, and hold harmless NCEI and its employees or affilitates against any claim, loss, liability or expense, including attorneys' fees, resulting from loss of or damage to property or the injury to or death of any person arising out of the use of the data.
Fees
  • Free for online download
Lineage information for:series
Lineage Statement The April 1, 1946 marigrams were stored in boxes until scanned into digital data in 2016-17.
Processor
  • DOC/NOAA > Center for Tsunami Research
Processing Steps
  • Marigram TIFF images were loaded into GraphClick and x,y axes were defined for 24 hour periods using the 4 known points option (coordinates at the bottom-left of the graph, bottom-right, top-left and top-right). This option was chosen over other available options to better represent images that may have had a tilted, wrinkled, warped or otherwise damaged paper record. Data points were individually added along the data curves by clicking on the center of the curved line with GraphClick recording x,y values each of those points. These x,y values were exported from GraphClick as a text file and transferred to Microsoft Excel 2016 for formatting of time, units and other general file formatting required for archival. CSV files were converted to netCDF with associated metadata. For records with curved vertical axes, one of the vertical graticules was digitized to create a table of corrections to the x axis as a function of height, and fit with a spline interpolation.
  • On any records that included periodical height/time information written on the marigram, such values were compared with the numerical values produced by GraphClick for consistency.
  • Values were compared against digital 1 hour data provided by the station operators where available.
  • Each station was checked as necessary for observance with Daylight Savings Time.
Source Datasets
Last Modified: 2020-09-03
For questions about the information on this page, please email:haz.info@noaa.gov