In the past few days, lightning has spread throughout Germany, which is quite normal in some places.
Lightning has been counted from space since 1995. The distribution of global lightning frequency is measured with the help of two satellites, the OTD (Optical Transient Detector) and the LIS (Lightning Imaging Sensor). According to this, there is an annual average of around one to four lightning strikes per year and square kilometer in Germany, with the lightning frequency in southern Germany being higher than in the north.
Lightning locations with a higher resolution indicate the Black Forest and the Rhine-Neckar and Rhine-Main areas as the regions with the highest lightning rate nationwide. Peak values of up to 10 lightning bolts per square kilometer and year can also occur here. The distribution is strongly influenced by regional peculiarities of the landscape: the rate is higher in the low mountain ranges and in urban centers. In the first case, hills and mountains ensure the necessary forced lifting of the thunderstorm-prone air mass, in the second case, higher temperatures and more dirt particles in the air favor thunderstorm formation. The proximity to the sea ensures moderate temperatures in summer, making heat thunderstorms less likely.
Thunderstorms need humid and warm conditions, which is why more than 90 percent of all lightning strikes are registered here in the summer months of July and August. It is therefore not surprising that so many flashes can be observed in the tropics. In the Congo Basin in equatorial Africa, more than 50 per square kilometer are counted per year, in polar latitudes, on the other hand, almost none. Only about 25 percent of all lightning strikes reach the ground, most discharge between the storm clouds or even within a storm tower.
The accumulation in northern India is also clearly visible, where the monsoon clouds in the Himalayas rain down and the clouds grow into severe thunderstorms as they rise. In the Sahara, on the other hand, the necessary humidity is missing, which is why thunderstorms are very rare there. Although there is an abundance of moisture on the world’s oceans, the air cannot heat up sufficiently in the afternoon, which is a prerequisite for afternoon heat thunderstorms. This is because water has a very high heat capacity and hardly changes its temperature over the course of the day.