Long Term Magnetogram
The long term magnetogram is designed to plot geomagnetic activity over the course of a year.
- The dark green line is hourly activity
- Bright green line/dots are confirmed auroral sightings as recorded in Otago/Southland
- Red line/dots are where the hourly activity exceeds a "storm threshold". This is an empirically derived level that seems to coincide with observed geomagnetci storms