Hotspot volcanoes

Probing the depths of Costa Rica’s volcanoes

I am fascinated by the raw power of volcanoes. As a volcanologist, being in a crater and feeling the movement and pressure beneath your feet is almost a spiritual experience.

I am based at the National University of Costa Rica in Heredia (I also have an affiliation with the University of New Mexico in Albuquerque). We are surrounded by very active volcanoes here, including Poás and Turrialba. I call craters my natural laboratory.

My job here is to warn people of potential dangers. I have set up remote systems to perform near real-time monitoring so that we can be alerted immediately to any changes in the composition of the gas emitted by the volcano, indicative of an upcoming eruption.

In this photo, I’m on the Olca volcano in northern Chile, helping to determine where the carbon released by local volcanic systems comes from. My collaborators and I traveled 5,000 kilometers of desert, sampling the gas exiting the Earth’s crust through the subduction zone.

I am photographed using a titanium tube that we drive into the ground as close to the gas source as possible to draw the gas into a glass vial filled with sodium hydroxide solution. The gas bubbles and condenses, and we later measure its composition in the lab. The glass goes up to almost 100°C — so I wear a glove. The rest of my clothes protect me from the sun at very high altitudes, and constantly smell of sulphur. That does not bother me. You get used to this smell.

Volcanoes have personalities and change from year to year. Volcanology here used to involve a scientist from a western country flying in, taking samples and saying “here’s the composition of the gas”. It is useful, but not sufficient — these are dynamic systems. I am building a longer and deeper understanding of the volcanoes of Costa Rica. That’s the beauty of being based here: finding that deeper perspective and contributing to local science.