EGU21-2446
https://doi.org/10.5194/egusphere-egu21-2446
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

The Earth's magnetic field variations at the Algerian magnetic observatory of Tamanrasset from 1932 to 2020.

Lemgharbi Abdenaceur1, Hamoudi Mohamed2, Abtout Abdeslam1, Abdelhamid Bendekken1, Ener Aganou1, Hemmi Abderrahman1, and Mansouri Abdallah1
Lemgharbi Abdenaceur et al.
  • 1Center for Research in Astronomy, Astrophysics and Geophysics ,CRAAG,Tamanrasset research unit, geophysics, Algeria (lemgharbi.geomag@gmail.com)
  • 2University of Science and Technology Houari Boumediene , and Geophysics Laboratory - Algeria

In order to understand the spatial and temporal behavior of the Earth's magnetic field, scientists, following C.F. Gauss initiative in 1838 have established observatories around the world. More than 200 observatories aiming to continuously record, the time variations of the magnetic field vector and to maintain the best standard of the accuracy and resolution of the measurements.

This study focused on the acquisition and analysis of the magnetic data provided by the Algerian magnetic observatory of Tamanrasset (labelled TAM by the International Association of Geomagnetism and Aeronomy). This observatory is located in southern Algeria at 5.53°E longitude, 22.79°N Latitude. Its altitude is 1373 meters above msl. TAM is continuously running since 1932, using old brand variometers, like Mascart and La Cour with photographic recording at the very beginning. Nowadays modern electronic equipment are used in the framework of INTERMAGNET project. Very large geomagnetic database collected over a century is available. We will describe the history and the various improvement of the methods and instrumentation.

Preliminary analysis of time series of the observatory data allowed to distinguish two kinds of data: the first type, with low resolution, collected between 1932 and 1992. This data set comes from the annual, monthly, daily and hourly means. The second one with high resolution is represented by minutes and seconds sampling rate since 1993 when TAM was integrated to the world observatory network, INTERMAGNET. Part of the second dataset contains many gaps. We try to fill these gaps thanks to mathematical methods. Absolute measurements and repeat station data allow better accuracy in the secular variations and an improved regional model.

Keywords: TAM observatory, temporal variation, terrestrial magnetic field, secular variations, INTERMAGNET.

How to cite: Abdenaceur, L., Mohamed, H., Abdeslam, A., Bendekken, A., Aganou, E., Abderrahman, H., and Abdallah, M.: The Earth's magnetic field variations at the Algerian magnetic observatory of Tamanrasset from 1932 to 2020., EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-2446, https://doi.org/10.5194/egusphere-egu21-2446, 2021.

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