Volcano Watch — Volcano scientists roam the streets in Heraklion, Greece
Heraklion is the largest city on the island of Crete in Mediterranean Sea. The island isn’t volcanic, but other Greek islands dotting the sea surface nearby are, and the city recently hosted a “Cities on Volcanoes” scientific meeting.
Volcano Watch is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and affiliates.
During June 12–17, USGS volcano scientists, including three from the Hawaiian Volcano Observatory, gave talks, presented research, convened sessions, attended workshops, and facilitated discussions both in person and virtually at this meeting (https://citiesonvolcanoes11.com/).
Cities on Volcanoes meetings are sponsored by the International Association of Volcanology and Chemistry of the Earth’s Interior, a society of scientists from around the world that specialize in volcanology and related disciplines.
The recent meeting in Crete is the 11th in a series of “Cities on Volcanoes” meetings that began in 1998. These meetings, hosted in communities impacted by volcanic processes, bring together volcano scientists and emergency responders with the goal of promoting these different perspectives to better understand volcanoes and lessen their impact on communities.
USGS scientists at the recent Cities on Volcanoes meeting presented on a range of topics, including dynamics and responses to recent eruptions, such as the 2018 Kīlauea and 2022 Hunga Tonga-Hunga Ha’apai eruptions, developing emergency-preparedness, eruption, and response plans, developing hazard zones and hazard assessments, using new tools for eruption monitoring, new insights gained from looking at eruption deposits, and compilations of official information on volcanic activity.
Previous Cities on Volcanoes meetings were held in other countries with cities on or near active volcanoes: Italy, New Zealand, the United States, Ecuador, Japan, Spain, Mexico, Indonesia, and Chile. The third Cities on Volcanoes meeting was appropriately hosted in Hilo, Hawaii, in 2003!
Why was Hilo chosen as the host of the third Cities on Volcanoes meeting? Hilo town is built on the northeast slopes of the massive volcano Mauna Loa: it is a city on and affected by a volcano. Over the past couple of centuries, lava flows from the Northeast Rift Zone of Mauna Loa have flowed downslope towards Hilo in 1984, 1942, 1935–1936, 1880–81, 1855–56, and 1852.
These lava flows are easily visible as you drive the Daniel K. Inouye Highway across the center of the Island of Hawai‘i (Hawaii Route 200, also known as the Saddle Road). Their dark colors and lack of vegetation attest to their young ages. The flows created a patchwork of vegetated kīpuka through which several Nā Ala Hele trails meander (https://hawaiitrails.hawaii.gov/trails/#/).
Guatemala, in Central America, will host the next Cities on Volcanoes gathering in February of 2024. Guatemala has over 20 volcanoes, two of which have erupted this year: Santa Maria and Volcán de Fuego.
No volcanoes in Greece are currently erupting; however, the picturesque town of Santorini is on the largest of several islands that formed during the caldera-forming eruption of Santorini volcano roughly 3,600 years ago.
Prior to the eruption, the island was much larger, known as Thera, and inhabited by members of the Minoan Civilization. The eruption is sometimes referred to as the Minoan eruption as it occurred during the peak of the Minoan Civilization, a society known for its construction of paved roads, advanced ships, and the first in Europe to use a written language.
The caldera that formed during the eruption is mostly submerged. The surrounding islands represent the highest parts surrounding the caldera, above the sea surface. The eruption was large enough to cause a tsunami that affected the nearby island of Crete. Work by archaeologists suggest that the fall of the Minoans might have been related to the legend of Atlantis—a city that was lost to water.
Like Heraklion and other hosts of Cities on Volcanoes meetings, Hilo remains a city affected by volcanoes. This is sometimes easy to forget given the decades since the last encroaching lava flow. If you find yourself roaming the streets of Hilo, remember that the patchwork of lava flows and kīpuka upslope are a reminder of past eruptions.
