Is the Arenal Volcano waking from its slumber?

This photo taken on Friday shows a distinctive plume rising above the Arenal Volcano (Twitter)

October 5^th, 2015 (ICR News) Visitors and residents near the Arenal Volcano have reported seeing plumes of “smoke” rising from the volcano in recent days, sparking fear – or better, hope on the part of area tourism entrepreneurs – that Arenal might be waking from the state of slumber it entered in 2010.

Scientists, however say that visitors and residents have no reason to raise their fear – or hope – that the volcano is waking.  Instead, what is being seen is steam – not smoke – caused by a recent increase in rainfall, according to experts.

The Volcanolgical and Seismological Observatory of Costa Rica (OVSICORI) said that the plumes are water vapor, the result of a recent increase in rainfall that subsequently makes its way into the fractures of the volcano, producing steam when it reaches heat sources deep inside, which later rises and escapes through the volcano’s crater.

The same type of activity was seen in September 2013, and experts say that still-hot areas deep inside the volcano could take 100 or 200 years to completely cool.

Experts also say that there has been no recorded seismic activity at the volcano, and any ‘rumbling’ sounds are likely falling rocks and boulders after recent heavy rains.

Arenal Volcano’s slumber could last 800 years… or it could explode violently

Costa Rica’s iconic Arenal Volcano, which has been essentially inactive since 2010, could continue its slumber for hundreds of years – or explode in a violent eruption – according to an expert at the Volcanological and Seismological Observatory of Costa Rica.

“The volcano could remain in a dormant state for a long period of time as it has [in the historical record].  It could remain dormant for 600 or 800 years, or it could reactivate in an explosion such as in 1968.  It all depends on internal conditions of the volcano that we cannot see,” volcanologist Javier Pacheco said last year.

Arenal at one point had been believed to be a long dormant volcano, prior to a sudden and violent eruption on July 29^th, 1968.  The eruptions continued unabated for several days, burying over 15 square kilometers with rocks, lava and ash.  When over, the eruptions had killed 87 people and buried the villages of Tabacón, Pueblo Nuevo and San Luis.  During the most violent explosions, the volcano flung giant rocks weighing several tons more than a kilometer away at a speed of 600 meters per second.

The volcano remained active until 2010, transforming the area into one of the country’s most popular tourist destinations.

Pacheco said last year that Arenal seems to be deepening its sleep. “For example, there are no carbon dioxide emissions in the amounts seen before, in fact they cannot even be measured as they are below what our measurement devices can detect,” Pacheco said, adding that there is almost no seismic activity at the volcano.

While Pacheco said the volcano could remain dormant for hundreds of years, “This could be reversed at any time by a new magmatic intrusion,” he said.