Last Week
Solar activity was at moderate levels in the last week. There were 8 C-type CMEs yet most of them were not Earth-directed. There were 4 M-class flares yet only one of them has been observed with a CME. Solar wind speed was greater than 400 km/s throughout most of the time. There was an interplanetary shock on March 10th due to the March 6th CME. Kp level increased up to 6.
The most significant solar activity of the week was the CME observed on March 10th. The CME was Earth-directed and had a speed of 677 km/s. Its arrival happened on March 13 and caused a geomagnetic storm. Kp level increased up to 6 and remained at that level for 12 hours. Dst indice decreased to -87 nT. AE indice increased up to 2000 nT. The IMF Bz component fluctuated between -24 and 24 nT.
Solar activity was at low levels within the last 24 hours. There were 41 sunspots on the visible disk with 5 active regions. There were no significant solar flares. The only coronal hole is at the South pole. The solar wind speed had a decreasing trend which was from 430 to 341 km/s. The strength of southward IMF was 4.2 nT at its maximum. The minimum magnetopause standoff distance was 10 Re. The maximum Kp level was 2 which indicates quiet conditions. The geomagnetic indice Dst varied between -17 and 1 nT while AE was below 500 nT. The F10.7 solar flux was 107 sfu which is normal during the ascending phase of the solar cycle.
The solar activity is expected to remain at low levels in the following days. A slight increase in the solar wind speed is expected due to the coronal hole at the South pole. Moreover, a slight disturbance is expected due to the arrival of March 13 CME as a glancing blow, yet no geomagnetic storm is expected. ASSA flare model predicts the occurrence possibility of C, M, and X class flares as, 37%, 5%, and 0% respectively due to the present 5 active regions.
Forecaster: Ezgi Gülay
MSc. Student
Faculty of Aeronautics and Astronautics, ITU