A palaeontologist/geologist will be joining the Jewels of the Arctic trip, which visits Spitsbergen, Greenland and Iceland, to share his knowledge of volcanoes, fjords and rocks.
In examining changes in the activity of the sun and volcanoes, Trenberth and Fasullo estimated that they can account for no more than a 20 percent reduction in the Earth's energy imbalance, which is what causes global warming.
Others thought it was formed by blankets of ash from volcanoes.
These towns (and Pucón to the north) are close to a series of national parks that protect the lakes and forested slopes of the Villarrica and Puyehue volcanoes.
Things look set to change, though, as the country opens up – an airport opened recently on Ometepe island, a Unesco biosphere reserve known for its twin volcanoes.
In some areas, should the winds change and the volcanoes' acidic smoke billow over farmland, acid rain can destroy an entire harvest.
The people here have good reason to keep a close eye on the volcanoes around them.
Watch a turtle nesting, explore the world's oldest rainforests, bathe in mud volcanoes... this new family group tour combines wildlife, culture, education and adventure.
Overshadowing the landscape was the active Galera volcano, which marked my arrival at a long corridor of volcanoes forming the backbone of neighbouring Ecuador.
Although the famous Tren Crucero was created for trade purposes, it now operates at a leisurely speed for tourists wanting to see banana plantations, active volcanoes and plenty of wildlife on a four-day trip.
Activities on offer locally include whale watching, excursions to snow-capped volcanoes, glaciers, waterfalls and spouting hot springs, snowmobile safaris, horse riding and soaking in the naturally-heated Blue Lagoon geothermal spa.
