Pressure wave of volcanic eruption Tonga in the Netherlands measured

The consequences of the volcanic eruption of the Hunga Tonga-Hunga Haapai volcano in Tonga can now be seen across the perimeter. The eruption was also measured at weather stations in the Netherlands: a little after 20.00 hours, at Woensdrecht air base, the air pressure increased by a 0.8 hectopascal, and then 2 points dropped. A shock wave that could be measured even on sports watches:

The shock wave precedes the other effects of the eruption, then the water follows. Tsunami warnings have been issued along the shores of the entire Pacific Ocean. In Tonga, people were evacuated and streets were white.

Cars in the water

In Japan and Hawaii, the tsunami has been measured as a long wave of about 80 centimeters high. In Oregon on the US West Coast, where tsunami warnings were also issued, a wave of about 30 centimeters high was eventually measured. Oregon is about 8700 kilometres away from Tonga:

How intense a tsunami becomes is difficult to predict just after an eruption. In California, there is also a warning and the waves do not exceed an inch or 80, but that is enough to subwater a parking space and a number of cars.


The eruption is well captured by several satellites. In various animations, the ash plume of more than 500 kilometers wide can be seen. What is less visible underneath is lightning. This is due to the fact that the hot ash is forcefully pushed into the cold air:

Whatever the ash plume conceals is what the volcano looks like now. Satellite images taken prior to the eruption show that much of the island had fallen into the sea:

The latest reports from Tonga are also hampered by the eruption. After the eruption, the internet cables towards the island state are offline. It is not clear if they are damaged or simply fell out. Internet connections via satellites are also disturbed by the axis.


Neighboring New Zealand has now offered help, but Tongolies there also say that it is not possible to reach relatives on the islands.