You see a similar pattern in the southern hemisphere, but not so pronounced because there isn't as much land outside the tropics. Scientists discuss biology, safety, and statistics of lightning strikes. Poster papers on hurricanes and tornadoes summarized. Thunderstorms generate elusive and mysterious sprites. Preview of the 11th International Conference on Atmospheric Electricity.
Variations show up even from one year to the next.
It's tightly coupled with the dynamics and physics of the storm. We use it to monitor its evolution and life. Their view is limited to a small area directly under their satellites, so global or even regional monitoring is impossible. To fill that role, Christian and his team are studying designs for a Lightning Mapping Sensor that would be placed aboard geostationary weather satellites. NASA's Earth Science Enterprise Information on Earth Science missions, etc.