Nature of project: **data analysis**, software

Available to students on full-time physics degree schemes only.

In certain years the Earth's magnetic field variations are extremely small. In this context it is assumed the Sq current system will not be influenced greatly by the solar wind. The solar-quiet (Sq) magnetic field variation is the cause of an ionospheric current system. Heating on the dayside and cooling on the night side of the atmosphere generates winds that drive plasma against the geomagnetic field, inducing electric fields and currents in the region between 100 and 140 km in height. The current system remains relatively fixed to the Earth-Sun line and produces regular, broad-scale daily variations that are seen directly in magnetograms of geomagnetic quiet days, hence the name Sq. In this project the student is required to map the Sq current system using Faraday's laws of induction and vector analysis. Several days of data will be chosen using the aa geomagnetic index and the resulting maps will be investigated.

The student will

1. Learn to download data and read it.

2. Plot vector maps for the Earth using Matlab.

3. Understand the Geospace environment.

4. Investigate ionospheric currents.

This project is sponsored by QinetiQ. The software needed will be supplied.

*A successful project will develop beyond the above in one/some of the following directions:*

Development of a 2-D model of the Sq system in time would enhance the research in this area.

The student has a choice of days and the physics involved differs as to the choice of data chosen.

If a full year is analysised the ionospheric weather will be mapped for that year.

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

*This project is only available as a Y3 project.*

Please speak to **Heather McCreadie** (hem18) if you consider doing this project.

*Initial literature for students:*

- Matsushita, S. (1968), Sq and L Current Systems in the Ionosphere. Geophysical Journal of the Royal Astronomical Society, 15: 109–125. doi:10.1111/j.1365-246X.1968.tb05751.x
- Stening, R. J. (2008) The shape of the Sq current system, Ann. Geophys, 26,1767-1775 www.ann-geophys.net/26/1767/2008/angeo-26-1767-2008.pdf
- Basic Space Plasma Physics by Wolfgang Baumjohann, Rudolf A. Treumann
- Fathy, I., C. Amory-Mazaudier, A. Fathy, A. M. Mahrous, K. Yumoto, and E. Ghamry (2014), Ionospheric disturbance dynamo associated to a coronal hole: Case study of 5–10 April 2010, J. Geophys. Res. Space Physics, 119, 4120–4133, doi:10.1002/2013JA019510.

The initial ideas for the model are challenging. The system will be modelled first using Matlab and then the data presented, analysed and compared with the model. Extra support will be given to model the current using Matlab.

milestone | to be completed by |
---|---|

chosen and downloaded the data and checked it | end of October |

model outline | end of November |

Software development for display of data. | end of February |

Comparison of the data with the model. | Easter |