Conveners
Monitoring and Risk Assessment: MRA one
- Karen Strehlow (GEOMAR Helmholtz Centre for Ocean Research Kiel)
Monitoring and Risk Assessment: MRA two
- Ulrich Kueppers (Ludwig-Maximilians-Universität München)
- Lea Scharff (Institut für Geophysik, CEN, Universität Hamburg)
Considering the hazards of volcanic eruptions, especially the influence of volcanic ash on human health and infrastructure incl. aviation, good monitoring systems are important in order to warn the population of dangers at an early stage. Using radar systems it is possible to detect small particles like rain drops or volcanic ash during most weather conditions. To increase the speed and...
On July 3, 2019 a rapid sequence of paroxysmal explosions at the summit craters of Stromboli (Aeolian-Islands, Italy) occurred, followed by a period of intense Strombolian and effusive activity in July, and continuing until the end of August 2019. We present a joint analysis of multi-sensor infrared satellite imagery to investigate this eruption episode. Data from the Spinning Enhanced Visible...
Small steam-driven volcanic explosions are common at volcanoes worldwide but are rarely documented or monitored; therefore, these events still put residents and tourists at risk every year. Steam-driven explosions also occur frequently (once every 2-5 years on average) at Lascar volcano, Chile, where they are often spontaneous and lack any identifiable precursor activity. Here, for the first...
The observation of volcanic sulphur dioxide (SO$_2$) emissions enables to monitor volcanic activity by quantifying degassing fluxes of volcanic plumes. Recently applied imaging techniques based on non-dispersive optical remote sensing (SO$_2$ cameras) reach a high spatial and temporal resolution. However, due to the limited spectral information, this technique lacks sensitivity, and...
Atmospheric ozone plays an important role in the chemistry of volcanic plumes, for instance its photolysis is a source of hydrogen radicals and it oxidises halogen atoms and hydrocarbons. The ozone level inside a plume is therefore a good indicator of turbulent mixing and chemical activity. For instance, already small amounts of halogen oxides can lead to significant or even complete O$_3$...
One of the main compounds emitted by volcanoes or volcanic fields is CO$_2$. This is not only emitted from localized craters, but can emerge as distributed and fugitive emissions on extended volcanic areas. In this situation it is of interest to explore the distribution and horizontal concentration profiles of the CO$_2$-emissions.
For this purpose new drop-sondes for sensor measurements of...
A 10 x 10m subarea of a hot and heavily CO$_2$ emitting mofette on a hilly grassland at Caldeiras da Ribeira Grande, located on the north flank of Fogo Volcano, was studied. A 1 x 1m grid was laid on top of the area and at each intersection, soil gas measurements were performed at three different depths. CO$_2$, CO and O$_2$ were measured. In addition, soil CO$_2$ flux using the accumulation...
The Santiaguito volcanic dome complex, Guatemala, has been continuously active since its formation in 1922 at the flank of Santa Maria’s eruption crater. Over time, four volcanic domes formed of which only the oldest one, Caliente, is still active today. Santiaguito’s, or more precisely Caliente’s, eruptive behavior is characterized by several eruptions a day with varying frequency and...
Imaging growing lava domes has remained a great challenge in volcanology due to their inaccessibility and the severe hazard of collapse or explosion. Changes in surface movement, temperature or lava viscosity are indicators for the current state of the activity and are thus considered crucial for hazard assessments at active lava domes. Here, we present results from a series of repeat survey...
It is 135 years after the 1883 volcano-triggered tsunami disaster, when Krakatau volcano became once more the source of a deadly tsunami striking without warning. We use data recorded on the ground and by satellite, to show that the volcano was in an elevated stage of activity throughout the year 2018, producing thermal anomalies associated with volcanic deposits, an increase of the island...
