Swarm DISC project
Auroral Electrojet boundaries from Swarm data

ESA Swarm mission

Swarm DISC

Swarm Data Flow

VirES for Swarm

With their near-polar orbits, the three Swarm satellites provide an excellent opportunity for investigating ionospheric currents at high latitudes. In this project (Auroral Electrojet and auroral Boundaries estimated from Swarm observations, hereafter Swarm-AEBS) a set of three new products will be designed and applied to the data of each Swarm satellite separately, for characterizing the ionospheric currents at auroral latitudes. This project started at the beginning of 2018 and its duration is one year.


We will implement two separate algorithms that both determine latitude profiles, peak current densities and boundaries of Auroral Electrojets (AEJs) based on the measurements of magnetic field intensity at 1 Hz sampling provided as Swarm L1b product (MAGx_LR_1B). In addition, an algorithm that determines the boundaries of the auroral oval will be provided. The two algorithms to be used for AEJ intensity and boundary detection will be based on previously developed methodologies using Spherical Elementary Current Systems (SECS) and Line Current (LC) systems. The auroral oval boundaries will be detected with an automated routine analysing squared intensities of small scale Field-Aligned Currents (FACs) as derived from the Swarm L2 Cat-2 product (FACxTMS_2F, the single satellite approach).


The above described AEBS products will be determined retrospectively from the start of the nominal Swarm mission until the beginning of the operation phase of our project and as regular daily updates to Swarm data services until the end of the project. The products will be validated in three steps:

  • Sanity checks for each product separately by comparing statistics from the three satellites
  • Validation with independent reference material
  • Cross-comparisons between the SECS and LCS based results and between the AEJ boundary and auroral oval boundary results

    The Consortium conducting the survey consists of three research institutes:

  • Finnish Meteorological Institute (FMI, Contractor)
  • Helmholtz-Centre Potsdam - GFZ German Research Centre for Geosciences (GFZ, Sub-contractor)
  • Technical University of Denmark (DTU Space, Sub-contractor)


    The flows of data and products in the Swarm-AEBS project are described in the chart below.


    Last update: April 12 2018 by kirsti.kauristie at fmi.fi