GEOL/PHYS 6650 Geophysics graduate seminar: Geomagnetics. Every Wed  11am in BESC 355.

GEOL/PHYS 6650 Syllabus

Geomagnetism Class Spring 2016: 1 hour long lectures once in a week starting January, 2016, intended for graduate students of CU Earth Sciences and other interested researchers.

The Earth is like a giant magnet, surrounded by a magnetic field. This magnetic field, which is a vector with both direction and intensity, is generated by a dynamo process in the fluid outer core of the Earth. Due to the chaotic movement of the core fluid, the Earth's magnetic field gradually changes over the years.

The magnetosphere is a large cavity produced by the Earth's main magnetic field. Essentially, the charged particles of the solar wind cannot move across magnetic field lines and are deflected around the Earth. The complex interactions of the Earth's magnetic field with the solar wind give rise to a multitude of electric current systems, which flow at typical distances of 2 to 20 Earth radii from the surface.

The ionosphere consists of several layers, generally referred to as D (60 km - 90 km), E (90 km - 150 km) and F ( >150 km) regions. Horizontal ionospheric currents, such as the polar electrojets, the equatorial electrojet and the Sq (solar quiet) current systems are largely confined to the E region. At night time, however, when E region conductivity is low, currents in the higher F region can play an important role. This is particularly true for the tropical ionosphere.