7.1. INTERMAGNET WEB Site

The INTERMAGNET web site provides background information about INTERMAGNET, its structure, and participating organizations, countries and IMOs (INTERMAGNET Magnetic Observatories).

The web site offers access to various data products:

The annual definitive data published with a Digital Object Identifier (DOI).
Magnetograms and data files of reported and adjusted minute values from all the IMOs.
The Online Technical Reference Manual.
The INTERMAGNET application form.

INTERMAGNET moved away from in-house maintained servers towards free cloud-based possibilities to deploy the web site.

The following underlying technologies were selected for the web site :

a GitHub repository for all software, web site development and discussion forums : https://github.com/INTERMAGNET
The INTERMAGNET web site has been designed using GitHub Pages (https://pages.github.com/).
The Online Technical Reference Manual is produced using the sphinx framework making it possible to generate both pdf and html versions of the manual The manual is automatically built and deployed using the services offered by readthedocs.org.

The metadata and online data are hosted by the British Geological Survey (BGS). The annual definitive data are deployed on the servers of the German Research Centre for Geosciences (GFZ).

7.1.1. WEB Site Address

The INTERMAGNET web site address is: https://www.intermagnet.org/. This gives access to the home page from where required information about INTERMAGNET is available. The source code is available on the INTERMAGNET GitHub.

7.1.2. Online Technical Reference Manual

The Online Technical Reference manual can be found on the subdomain https://tech-man.intermagnet.org/. It is also possible to download the manual in different formats.

On the right side, you will find links to download the manual in PDF or HTML format.

There are three versions available:

stable : The latest official release (the most up to date version to be used as a reference).
latest : The current working version with accepted changes but not ready for an official release.
development : This version may contain errors and/or proposed changes not yet accepted.

The stable version should be the only one used as reference.

7.1.3. Downloading Data

Geomagnetic observatory data can be downloaded using a web browser by either using DOIs for definitive data or using the web data distribution interface for all data types including definitive data. Until 2015, the annual definitive data was released on a physical media (see APPENDIX C2). From 2015 onward, the intermagnet definitive data is published yearly with a Digital Object Identifier (DOI) which includes all definitive data since 1991 to the publication year.

7.1.3.1. Downloading Data Using DOIs

Beginning with the publication of the definitive data for 2015, INTERMAGNET stopped publishing individual years of data and started publishing the entire, cumulative definitive data set since INTERMAGNET’s first recorded definitive data in 1991.

This DOI-referenced annual data set is known as the “INTERMAGNET Reference Data Set” (IRDS). The IRDS comprises all INTERMAGNET one-minute definitive data since 1991 and is annually updated with a new year and occasional corrections to previous releases. The different releases of the IRDS can be found on the INTERMAGNET web site :https://intermagnet.org/data_download.html.

The IRDS are deployed on the servers of the GFZ German Research Centre for Geosciences. File names for IRDS data are formatted in the form mag<year>_def<year>.zip. The mag<year> section of the filename describes the year in which the data was recorded. The def<year> section of the filename describes the most recent annual INTERMAGNET publication in which the data was updated. Files where mag<year> = def<year> have had no corrections since their original publication. For example, “mag2015_def2016” indicates that this file is different from the first release “mag2015_def2015”.

The zip archive is organized in a number of subdirectories. Most of them are named with observatory IAGA codes, they contain information regarding a particular observatory. Further subdirectories provide country information about national operators of magnetic observatories. A complete set for one observatory consists of the following files (this example is for the year 2010):

x:\mag2010\sss\sss10mmm.bin (12 binary files in IAF format)
x:\mag2010\sss\readme.sss (1 readme file)
x:\mag2010\sss\sss2010.blv (1 baseline file)
x:\mag2010\sss\yearmean.sss (1 annual means file)
x:\mag2010\sss\sss10k.dka (1 text file of K-indices)
x:\mag2010\2010maps\country_id.xxx (1 map for each country (xxx = png or pcx))
x:\mag2010\ctry_inf\readme.country_id (1 readme-file for each country)
x:\mag2010\ctry_inf\country_idsrn.xxx (1 about-screen for each country (xxx = png or pcx))

Where:

sss is the 3-letter observatory IAGA code
mmm is the month
country_id is the three-letter country code

A binary file in IAF format (described in detail in Section 6.4 and APPENDIX C1) includes minute values as well as other accompanying data such as: metadata headers W01-W16, K indices, hourly and daily mean values.
A text file readme.sss contains meta-data and information about the observatory such as location, parent institute, personnel, equipment and instrumentation etc.
A text file sssyyyy.blv includes results of absolute control of geomagnetic observations and adopted baseline values. The format of this file is described in APPENDIX E4. Baseline data are considered by many experts as an indicator of data quality, especially with regard to observation of secular variation.
A text file yearmean.sss includes a listing of annual mean values for the observatory. The format of this file is described in APPENDIX C3. Most observatories publish all annual means, i.e. since the beginning of their activity. Some observatories also publish annual means for international geomagnetic quiet-days and disturbed-days.
A text file sssyyk.dka includes K-indices. DKA files are created by INTERMAGNET from the K index data includied in binary IAF files. if K-indices are not scaled by the IMO there is no DKA file.
The image file country_id.xxx shows the location of observatories of a given country.
The text file readme.country_id provides information about parent institute(s) in a given country.
The image file country_idsrn.xxx provides information about parent institute(s) managing IMOs in a given country in graphical form.

After unzipping the archive data can be accessed using INTERMAGNETs IMCDViewer software available for downloaded from the web site : https://intermagnet.org/software.html. See Section 7.2 for more info on the usage of this Data Viewer.

7.1.3.2. Downloading Data Using the WEB Interface

Reported and adjusted intermagnet data are available for many IMOs in near real-time. The availability of data files is dependent on the publishing delay and data embargo policy of participating institutes. If there is no publishing delay, data are available within 10 to 20 minutes after being placed on the server. The data covers the period from 1991 to present. In addition to data of reported and adjusted quality, quasi-definitive and definitive data may also be available for one-minute or one-second sampling rates in various data formats. Data are also available via web services and ftp. For further details and to download data, you can consult the INTERMAGNET web site: https://intermagnet.org/data_download.html

Plots of magnetic observatory data and information derived from the data are also available. These include:

Plots of X, Y, Z magnetic field components
Plots of H, D, Z magnetic field components
Plots of declination and inclination

7.1.4. Geomagnetic Activity

A map of geomagnetic activity is currently under development. The magnetic activity maps will show the range of the magnetic variation in each hour at INTERMAGNET observatories around the world. For recent events only those observatories with fast reporting capabilities can be presented.