Day: March 23, 2015

Sakurajima: shock wave and lightning

by

Volcanic lightning are rare phenomens which are difficult to capture on video. This one from Sakurajima volcano was made by a lot of single frames, each exposed for some seconds and animated via PC to a video sequence. The unique shots were licences from several TV station all over the world.

Sakurajima facts

Sakurajima means in English Cherry Blossom Island. It is an active strato volcano and a former island in the Bay of Kagoshima in Kyushu, Japan. The lava flows of the 1914 eruption caused the former island to be connected with the Osumi Peninsula.

The volcanic activity is erupting large amounts of volcanic ash. Earlier eruptions built the white sands highlands in the region. 

Sakurajima’s summit has three peaks: Kita-dake (northern peak), Naka-dake (central peak) and Minami-dake (southern peak). A smaller crater on its east side is called Showa. This is the site of most of the current eruptions.

Sakurajima is famose for its volcanic lightning. (Sources WIKIPEDIA & USGS)

Sakurajima: Volcanic lightning

by

Volcanic lightning on Sakurajima in Japan. The lightning occurs in ash-rich eruptions, mostly during first 20 seconds of the eruption. I saw a shock wave in one of the first morning of my observations in March 2015. This shock wave you will see in the video.

The story of volcanic lightning

I visited the Sakurajima in Japan several times in the past years: the volcanic lightning in the ash clouds always attracted me like a magnet! Photographing at the volcano is never easy, but to capture flash clouds requires special know-how and a lot of patience. I was on the road again with Martin Rietze and after the long flight we went straight to the volcano in the evening after our arrival in Kagoshima. We wanted to spend the night at our favorite place again and set up our cameras. It is about 3 km from the summit of Sakurajima, almost at the end of a small road leading to a lahar dam. But, oh dear, the property with the meadow was fenced in and the meadow was nice and clean and the ground was levelled. What now? With a bad conscience we bypassed the fence and set up our camp at the edge of a bush.

Already in the first night our patience was put to the test: the volcano was unusually quiet and produced only a few miserable ash clouds, so completely without lightning. Then in the morning, all the accumulated energy was discharged in a proper detonation! The generated shock wave was not only visible in the clouds above the crater, but could also be clearly felt as a short shock wave. After the lame night it got us going. But unfortunately the weather got worse and worse and we decided to break up our camp and set off for the volcano Aso. This volcano is about 2 hours drive away from Sakurajima. Aso was strombolian active in the last weeks and especially Martin heard its tempting call.

But, how could it be different, the bad weather reached the volcano with us. Shortly before the clouds closed, we caught a glimpse of the crater and a small ash cloud, then it started to rain. We explored the visitor center at the foot of the crater cone. The ascent to the crater was of course closed. I was quite surprised about the size of the parking lot: in summer there must have been a lot going on here! Well, the Japanese love and adore their volcanoes and like to go hiking there.

In the evening it started snowing and Martin and I spent an uncomfortable night in the car, without any volcano view. Since we had little time, we started the next morning to Sakurajima. We made a short side trip to the Kirishima volcano. There the weather was better and the volcanic landscape was impressive! If the volcano should become active again, you have to go there!

On the way to Sakurajima we stormed a supermarket: the prices in Japan are sometimes enormous! Instead of being self-sufficient, you can better go to one of the few fast food restaurants or buy ready-made schnitzels in a minimarket.

In the evening we took position at Sakurajima again. But also this night was quite quiet. In the morning we had another nice eruption, this time with better weather!

Slowly our time was running out, but the next night we should have more luck. Saku turned up and produced 2 eruptions with volcanic lightning shortly after each other. Our cameras rattled in continuous mode and hardly a flash of lightning slipped through our fingers. In the air was the rumbling of the eruptions and the crackling of electrical discharges that made the hairs on your neck stand up. We looked through our cameras almost euphorically and hoped for more, but no more flashes. That’s how it is at the volcano! You often need a lot of patience for a few precious moments of successful experience.

Picture gallery: Pico do Fogo

by

Pico do Fogo is Cape Verde’s most active volcano. Fogo is a large volcano with a summit caldera. In it grows the current volcanic cone. In November 2014 an eruption began. On the flank of the current cone a fissure was opened. Strombolian eruptions occur from several vents and lava flows moved in direction of the village of Portela. After a few hours the visitor center was destroyed and two weeks later most houses were burried under lava.

Story behind the pics

Since 2 weeks the Pico do Fogo on the Cape Verde Islands already erupted when the geonauts Richard, Martin and Marc reached the remote volcanic island. Before that, dramatic events took place: on the flank of the volcanic cone in the caldera, an eruption fissure opened up from the lava fountains and fed a lava flow. Only hours after the beginning of the eruption, the lava flow destroyed the National Park’s visitor center. The building had been inaugurated only a few weeks before. It was built with financial help from Germany.

Shortly afterwards, the lava changed direction and flowed slowly but inexorably towards the village of Portela. This was located within the caldera and about 4 km from the cone of Pico do Fogo. The lava flow increased periodically and soon reached the first houses away from the village. It was still hoped that the lava would spare the core of the village, but this hope proved to be in vain. Already on the first day of our stay at the volcano we witnessed how another house was devoured by the lava. Devoured is not the right word: the lava flow tore it from its foundations and pushed it at a snail’s pace until it broke and was enclosed by the lava. The lava flow also crawled across the road and then stopped on the other side. The heat above the lava field created tornados. One of these minitornados suddenly whirled up in front of us, hurled a meter-sized corrugated iron through the air and threw Martin’s camera and tripod over and tore the cap off my head. Sand crunched between my teeth.

We withdrew into the village and paused when loudspeaker announcements called for evacuation. Everyone had to leave the village immediately: elsewhere the lava flow threatened to spill over the temporary road. Many people panicked and tried to save their belongings as fast as possible. When we passed the place, the lava had stopped here too, at least for the moment.
We spent the next 2 days close to the eruption fissure, where several small cinder cones had formed in the meantime. We already marched up there at 4am. On the one hand we wanted to use the dawn at the volcano, on the other hand we set up sentries during the day to close off the area.

We approached the vents up to 250 m. So close to the site of the event I felt the tremor in my trouser bottom. In between there were stronger shocks that made the ground vibrate. Phases with Strombolian, ash eruptions and increased lava flow alternated. The next night the activity increased and the last hours of Portela began. A broad lava flow rolled through the caldera and buried two thirds of the site. Desperate soldiers tried to recover the wine from the winery and dragged the heavy wine barrels to higher ground. Our time at the volcano was already over, but a few days after our return home, the rest of the village was destroyed. Nature knows no mercy!