Pico del Teide with its strombolian cone
view from top of Montaña Guajara at 2700 meters
Fumaroles are openings in the Earth’s crust, often in the neighborhood of volcanos, from which volcanic gas escapes into the atmosphere. Fumaroles may occur along tiny cracks or long fissures, in chaotic clusters or fields, and on the surfaces of lava flows. From the perspective of groundwater, fumaroles could be described as a hot spring that boils off all its water before the water reaches the surface and as such appear in the atmosphere as steam mixed up with gases like carbon dioxide, sulfur dioxide, hydrochloric acid and others. Depending on the heat source, fumaroles can be of short or long term duration, ranging anywhere from weeks (if they occur above a fresh volcanic deposit that quickly cools) over months and years up to many hundreds of years (if they occur above a persistent heat source). The hotter the source is, the longer the fumarole will persist. The temperatures are between 70° C - 100° C (158° F - 212° F) or even more and thus are often emitted with higher temperatures than even geysers and hot springs, which are much more known to the public. The gases are often dangerous and are always a sign of active volcanism. Fumaroles also are not quiet, they however produce different types of sounds, while they steam. The sound has been described for example as hissing, roaring, and even thundering. The sounds are dependent on the force of the steam being released into the atmosphere. Slowly diffusing emissions will have lessened sounds. Forceful, blasting emissions produce greater sounds. If there is enough force, even the ground around the fumarole can tremble as the steam is released.
Pico del Teide itself is a strombolian type volcano with a cone of 150 meters height. With its summit (called 'Pilon de azúcar' - sugar loaf - have a detailed look at the picture above to figure out why) being more than 3700 meters above sea level it is the third highest volcanic complex on earth. It last erupted in 1492, the year when Christopher Columbus detected America. All later eruptions on the island were at different locations. Since the volcano still permanently ejects high temperature fumaroles of around 86° C (187° F) through tiny cracks inside the crater after more than 500 years of no eruption, it is obvious that there is still a huge and persistent magma source below the volcano. The fumaroles at the crater are also one of the many things, which are periodically measured to monitor volcanic activities in Tenerife. One more point might be of interest. In 2004 was noticed a significant increase in the number and severity of earthquakes (there were five felt earthquakes) on the island along with increased fumarolic activity at the summit of Pico del Teide. Everyone and even the scientists feared a new eruption on the island. Meanwhile however all measured values have been going back to normal at least for the time being.....
To get to the cache, you have two possibilities:
The hard way (Terrain difficulty 4)
Drive up to the National Park 'Cañadas del Teide' and park near 28°15.569 N 016°36.188 W. Have enough water and enough food with you. From there you just follow the well signed path up to Pico del Teide, which will bring you to the Cache area after at least 5 hours of climbing from around 2360 meters above sea level to 3717 meters above sea level. I do not say more about it, as it is described in many books and on the Internet. There is also the possibility to stay overnight in the 'Refugio de Altavista' 3250 meters above sea level. For more information and reservations see : Teleférico Teide (the site is provided in Spanish, English and German) . If you have more questions regarding this great experience, please contact me.
The easy way (Terrain difficulty 3))
Drive up to the National Park 'Cañadas del Teide' and park near the 'Teleferico' (cablecar) at 28°15.322 N 016°36.524 W. Buy a ticket (information about prices and hours at: Teleférico Teide The 'Teleferico' gets you up to 3550 meters to 'La Rambleta', from where you walk up to the top and the cache area.
No matter, whether you choose the hard or the easy way, prior to visiting this cache, you have to get a free of charge but written permit, which allows you to walk up the remaining 150 meters from 'La Ramblette' to the peak of the volcano. The website at: Teleférico Teide tells you too, how, when and where you can get this permit. Please also note (and this is not shown on the website), that the permit will only give you a two hour time window for access to the top of the crater. So better be there, if the clock starts to tick.
Note added 8/22/2010: Meanwhile you can also request the permit for the access to the crater online here: Request permit
To be allowed to log the cache execute the following tasks:
- The inside of the crater is covered by the accumulation/accretion of the fumaroles. Looking at the colours, what is the likely main chemical emitted by the fumaroles? You can't avoid to smell it too.
- Try to identify the number of fumaroles, ejecting steam, during a 3 minutes time frame, while you are there. How many did you count?
- How would you describe the sound, which you hear, when a fumarole ejects a steam cloud?
- What would you say? Are the emissions more 'slowly diffusing' or rather 'forceful blasting'?
- Send me an E-Mail with the answer to questions 1 to 4.
- OPTIONAL: Make a picture of you with your GPSr from any point at the trail on the top (the crater in the background). Upload it together with the log.
Please note, that the cache coordinates point to the middle of the crater and NOT to a point on the trail. NEVER leave the trail.
Note added 3/21/2013: Just send me the answers to the questions and log the cache. I will contact you, if one or more of your answers are wrong