Realtime Data and Archives
Below are plotted near-realtime data from the Callisto solar radio spectrograph, Stanford SID ionospheric monitor, and DIAS/TCD magnetometer. A local K-index for Birr is also given below, which gives a measure of the disturbance of the geomagnetic field, and may be an indicator of auroral activity.
Please visit the RSTO data archives to download FITS and text data files. If you do use these data for scientific purposes, please acknowledge "Trinity College Dublin". For magnetometer data, please acknowledge "Trinity College Dublin and the Dublin Institute for Advanced Studies”.
Solar activity from RSTO Callisto and GOES X-ray instruments
Earth's ionospheric activity from RSTO SID and GOES X-rays from Sun
Earth's magnetic field at RSTO from DIAS/TCD magnetometer
Geomagnetic activity from RSTO K-Index
The K-index quantifies the level of variation of the horizontal (H) component of the geomagnetic field in three-hour intervals. The
index ranges from 0 to 9 in a quasi-logarithmic scale, where K=0 indicates completely quiet conditions and K=9 indicates highly disturbed conditions.
The K-index gives a measure of how disturbed the Earth's magnetic field is in Birr. Large RSTO K-indices can be used to indicate that the northern lights (aurora borealis) may be visible from Ireland.
The K-Index value given in the above graph is calculated using the FMI (Finnish Meteorological Institute) method. This method allows us to estimate and subtract the solar-quiet variations in the magnetometer data. The steps undertaken in this method are as follows:
1) The raw magnetometer data is cleaned: a moving hour long window is used, and any values which deviate more than 3-sigma are discarded.
2) For each 3 hour block (00:00 - 03:00, 03:00-06:00, etc), the variation between the maximum and minimum of the two horizontal B-field values are compared to the following table to get an initial K-index n;
3) For each hour of the day, the average horizontal values for that hour +/- (n + m) minutes are calculated, where n is the initial K-index, and m is a constant which depends on the time of day. Together, these points give a rough estimate of the solar-quiet variation.
4) This rough estimate for the solar-quiet variation is then smoothed. This can be seen for a geomagnetically active day in the following plot:
5) The smoothed solar-quiet variation is taken away from the raw data. This is then used as in step 2 to get a secondary K-index.
6) Steps 3-5 are then repeated using the secondary K-Index to finally calculate the third and final K-index. This last K-index is what is displayed above.
A more detailed look at this method can be found here.