Volcán Poás is doing its part to promote the country’s tourism.
The Observatorio Vulcanológico y Sismológico de Costa Rica at Universidad Nacional has logged some spectacular eruptions at the volcano crater over May, and the estimate is that such activity will continue for two or four years, the experts there say.
The volcano has been erupting off and on over eight years, but from February to May there were some that shot from 200 to 400 meters (some 650 to 1,400 feet) into the air. Poás has one of the world’s largest calderas, so there were no times when any tourists who might have been on the observation area were endangered.
The Observatorio is getting a better account of eruptions now because there are Web cameras installed to keep an eye on the caldera. At night the experts have to rely on reports of changes in gas levels at the crater.
Most of what is ejected from the crater lagoon are sediment, rock fragments, water, vapor and sulfur.
The eruptions appear to be from the rapid expansion of water vapor and not the ejection of volcanic magma.
The information about the recent eruptions comes from a routine report from the Observatorio, which keeps close track with all sorts of measurement devices noting local earthquakes, temperature changes, and the gases.
Because of its easy access, Poás is one of the country’s most visited volcanos. The caldera is on many tourism tour agendas.