T-Phase Data Files
Read This Before Selecting Data Files The NOAA T-Phase data are organized into 1-Day files. The file names reflect the Hydrophone General Location, Year and Julian Date of the data. The nomenclature can be used for selecting the data files of interests. The format of these 1-Day NHP (NOAA HydroPhone) data files is described on the NHP Internal Format page.
Structure of the NHP file name
The NHP file name in general is as follows:
where ## and xxx are integers for latitude and longitude in degrees respectively; Yr is last 2 digits, such as '99' = Year 1999 and '00' = Year 2000 etc.; Day is Julian Date, day of the year in 001 to 366; the nhp suffix indicates it is the NOAA Hydrophone data file.
The first part of the file name H##[N/S]xxx[E/W] shows the general location of the Hydrophone. The "N" or "S" and "E" or "W" will be used to indicate the hemispheres of latitude and longitude. Yr and Day indicate the Date of the data.
The time range of data is indicated by a letter "A" to "Z" after YrDay. When the letter "Z" is shown, the NHP file is a 1-Day file from time 00:00:00 to 23:59:59. NHP files with the letters "A" to "Y" are not whole day files. For NHP files with the letter "A", the data are from the beginning of the date, 00:00:00, to some time before the NHP file with the letter "B" (if it exists) of the same Year and Day. For NHP files with the letter "Y", the data are from some time after the end time of the NHP file with the letter "X" (if it exists) of the same Year and Day to the end of the day, 23:59:59. For other NHP files with the letters "B" to "X" of the same Year and Day, their times are in between the end time of file with "A" and the start time of the file with "Y". An example of the nomenclature of NHP files is:
H*YrDayA.nhp < H*YrDayB.nhp < ... < H*YrDayX.nhp < H*YrDayY.nhp
Where t1 to tn are times in between 00:00:00 and 23:59:59.
1-Day File: H*YrDayZ.nhp from 00:00:00 to 23:59:59.
In most cases, only NHP files with "Z", "A" and "Y" will be found and a few files with "B" also exist. When NHP files with the letters "A" and "Y" of the same day and year are used, there is a time (data) gap during that day.
Examples of the NHP File Names
H16N049W99362Z.nhp is a 1-Day file of Year 1999 Julian Date 362 at the general
location of 16oN and 49oW.
Select NHP Data FilesThe following links point to the ftp sites that contain the NHP data files. Choose a location of interest and select a NHP data file to down load. Note that since the Year is represented by 2 digits, e.g. "99" for 1999 and 00 for 2000, NHP data files for 1999 may be shown at the bottom of screen.
If you use
the data in publications, please acknowledge the NOAA/ PMEL Acoustics
Project Office, Woods
Hole Oceanographic Institution, and Lamont-Doherty
Earth Observatory. Also, we would appreciate receiving a preprint and/or
reprint of those publications utilizing the data for inclusion in the NOAA
Acoustics Project bibliography. Relevant publications should be sent to:
Dr. Robert Dziak, NOAA Vents Program, 2115, SE OSU Drive, Newport, Oregon 97365.
National Science Foundation
Comprehensive Test-Ban Treaty Organization (contract #01/2/20/258)