Skip to main content

Arenal Volcano Eruption - October, 2005



Arenal photos above: October 28, '05 @ 11h pm & 11h39 pm. The last 2 pictures on Oct. 29 @ 1h11 am & 4h11 pm. Daytime the lava is grey, nighttime it's red & glowing (like a cigarette). Because we are near the equator the sunrise is roughly at 5h30 am & sunset is at 5h30 pm all year long. Calendar of sunrises, sunsets and moon phases for Arenal Costa Rica (opens in a separate window)


Arenal pictures above: strombolian eruption on October 27, '05 @ 6h51 am. By comparing the height of the volcano to the size of the hot ash & gas cloud, I estimate the diameter at about 275 meters (275 m x 3.3 ft/m =  907 feet). Night shot with lava glowing through the clouds on Oct. 21 @ 3h05 am.

A big strombolian eruption occurred toward the Tabacon Hot Springs (Northwest of the crater in the R1 - Maximum Risk Zone, see the Arenal Volcano map) on October 16, '05 @ 1h07 am with bombs (some were the size of a car) thrown at more than 1,000 feet (340 meters) away from the crater. Luckily the eruption was not big enough to be life threatening as everybody was asleep @ the Tabacon Resort. See a Arenal Eruption video .mp4 format here (100 KB) or a .mov Arenal Eruption animation here (97 KB). If you have a quick internet connection, you can see a better & higher definition 6 MB .gif animation here. Sorry that there is no sound yet with the video because we were @ 16 KM form the crater, and the thundering eruption sound reached us 45 seconds after the blast (as the speed of light is much faster than the speed of sound). If none of these links works for you, then get a nerd to fix your computer!

It's in black & white because it was shot with a small amateur video camera set on "night shot". Note that you need a tripod with this setting as the shutter speed is slow and it gets all blurry if handheld. I used a cheap & small aluminum table size tripod. Nothing was coming out of the volcano since 2 hours so I suspected that the pressure was accumulating and that an explosion would occur. I was taking pictures with my "real camera" but since I had with me an old video handycam, I set it up on a chair and let it run. Note that you should use your power adaptor unless you have a really good battery. My tape was only 1 hour long so when nothing special happened after the tape was finished, I just rewinded it and taped over it. Naturally the eruption occurred while I was changing the lens of my Nikon D70 so I don't have any good pictures of the event.

Photos above: October 16, '05 @ 9h39 pm. The rectangular light on the left side is the dam of Lake Arenal



Photos above: 13 October '05 all taken the same day @ 4h58 am (before sunrise @ 5h30 am), 8h40 am, 11h14 am (the bird in the clouds is a vulture), 7h28 pm (sunset @ 5h30 pm, there was a light rain but it was still possible to take some photos with the help of a rising half moon) & 7h54 pm (the rain stopped).


Photos above: 12 October '05 @ 4h51 pm (ash plume), 5h36 pm & 6h02 pm. See a time lapse animation of the ash plume eruption (274 KB).


Photos above: 5 October '05 @ 1h46 pm: on the right side of the first photo is a mass of semisolid lava the size of a truck bouncing on the steep slope of the volcano (50 meters or 150 feet between each black spots). 7 Oct. 3h20 & 3h50 pm: it was partly cloudy today but suddenly a huge column of smoke emerged, rising more than 1 km (3,500 feet). Note on the last picture that the heat of the volcano's plume punched a hole in the clouds letting the sun highlight the smoke.

All the photos on this website are the exclusive property of © and can not be reproduced without our written consent except for non-profit purposes with a credit to /