Sporadic E (Es) layers

Sporadic E (Es) layers are thin clouds of accumulated plasma, primarily occurring at midlatitudes during summer. They are generally formed at altitudes between 90 km and 120 km, which is equivalent to the upper MLT and the lower ionospheric E region. According to wind shear theory the forming process of Es is an interaction between the Earth's magnetic field, the ion concentration as well as the vertical wind shear.

At GFZ Potsdam, Es occurence rates are derived from GPS radio occultations. These data are used mainly to analyse the influence of neutral dynamics on Es.

Example of Es
Example of an Es

Es and tdal shear
Occurrence rate of Es at higher midlatitudes from GPS radio occultations, together with vertical shear of zonal wind measured with the Collm meteor radar

Publications within the project:

Fytterer, T., C. Arras, P. Hoffmann, and Ch. Jacobi, 2014: Global distribution of the migrating terdiurnal tide seen in sporadic E occurrence frequencies obtained from GPS radio occultations, Earth, Planets and Space, 66:79, doi:10.1186/1880-5981-66-79.

Jacobi, Ch., C. Arras, and J. Wickert, 2013: Enhanced sporadic E occurrence rates during the Geminid meteor showers 2006-2010, Adv. Radio Sci., 11. 313-318.

Fytterer, T., C. Arras, and C. Jacobi, 2013: Terdiurnal signatures in sporadic E layers at midlatitudes, Adv. Radio Sci., 11, 333-339.

Arras, C., J. Wickert, Ch. Jacobi, G. Beyerle, S. Heise, and T. Schmidt, 2012: Global Sporadic E Layer Characteristics Obtained from GPS Radio Occultation Measurements. In: Lübken, F.-J. (Ed.): Climate and Weather of the Sun-Earth System (CAWSES), Springer, Berlin, 207-222.

Arras, C., J. Wickert, S. Heise, T. Schmidt, and Ch. Jacobi, 2010: Global sporadic E signatures revealed from multi-satellite radio ocultation measurements. Adv. Radio Sci., 8, 225-230.

Arras, C., Ch. Jacobi, and J. Wickert, 2009: Semidiurnal tidal signature in sporadic E occurrence rates derived from GPS radio occultation measurements at midlatitudes. Ann. Geophys. 27, 2555–2563.

Arras, C., J. Wickert, G. Beyerle, S. Heise, T. Schmidt, and Ch. Jacobi, 2008: A global climatology of ionospheric irregularities derived from GPS radio occultation. Geophys. Res. Lett. 35, L14809, doi:10.1029/2008GL034158.

Last update 6 November 2014 by Ch. Jacobi