Krakatoa or Krakatau, in Indonesia, is part of the Ujung Kulon National Park, a UNESCO World Heritage property, and among the most (in)famous volcanoes in the world. From a geological point of view, it is part of the Indonesian island arc system generated by the north-eastward subduction of the Indo-Australian plate (Figure 1). Krakatau is now a caldera type of volcano thanks to the 1883 eruption, one of the most destructive and deadliest volcanic events in historical records causing a total of around 36000 deaths[1, 2, 3]. During this event, up to the 70% of the original island was destroyed, leaving a caldera structure, a ‘bowl-shaped’ depression, leading to a tsunami hitting the coastlines of Java and Sumatra and conspicuous tephra falling over the nearby inhabited islands.
If you have been regularly following our blog for this (almost) past year, you may have noticed that the field of natural hazards is coloured by many different shades. One more that I would like to present you today is about how the natural environment can affect human health.
It is a recognized fact that geo-materials can pose a threat to our health. One of the most striking examples is asbestos fibres, used industrially in large scale since the mid-19th century until discovered potentially harmful and finally declared carcinogenic. The field of research that addresses this interesting subject is medical geology, and to discover a bit more about it I interviewed Dr Ines Tomašek.
Ines, a former PhD student at Durham University in the frame of the MSC ITN VERTIGO, is currently a post-doc at Vrije Universiteit Brussel (VUB) and part of the International Medical Geology Association (IMGA). Her research focuses on the effect of volcanic eruptions on environmental and human health.
Not long ago on the blog, we have talked about natural groundwater quality triggered by geogenic factors and related hazards such as a high concentration of heavy metals. Today’s topic concerns the anthropogenic input of heavy metals into the water and how to solve its impact effectively. Industrial processes can lead to heavy metal bearing wastewater, which is commonly treated by inefficient purification methods. Therefore, it is time to think about alternative methods for recovering the metals that would otherwise pollute the water and create a hazard for the environment. In addition, the obtainable metal resources make their recovery attractive from an economic point of view. However, efficient removal and recovery of toxic metals from industrial wastewater streams is a major challenge. To understand better the subject and the potentiality of specific water’s treatments, we interviewed two PhD students, Kai Tandon and Iphigenia Anagnostopoulos, both working in the group of Prof. Dr. Soraya Heuss-Aßbichler at LMU Munich.
Volcanoes are often located in stunning and fascinating places of the world. Some volcanoes are in areas already heavily populated, like Popocatépetl in Mexico or that thanks to tourism become highly or more populated during certain times of the year, like Agung in Indonesia.
In addition to the charm, volcanoes can be and have been harmful to both lives and properties. The hazards posed by volcanoes erupting are various and can affect areas both in the vicinity and far away from the eruption. Common hazards are, for example, lava flows, pyroclastic density currents, ash fall, ejection of ballistic, lahars, volcanic gases as well as structural collapses causing landslides, and eventually, tsunamis if close to the sea or a lake.
There will be some indications, some precursors, that a volcano is going to erupt. However, the time between these signs and the eruptive event is highly variable and can range from days to months. Sometimes an eruption can happen without a clear warning and be fatal, like the Mt. Ontake eruption in Japan in 2014.
Preparedness is thus crucial: be aware of where you are, the possible hazards and how to prevent or minimize losses and accidents. Scientists from all over the world have been more and more working closely with the communities at risks from volcanic activity. Advancements in volcano monitoring help better understand the phenomena. And educational programs and emergency simulations are commonly put in place. However, how are tourists taken into account in hazard mitigation plans? How aware are tourists of the natural hazards they may encounter? Are visitor centres providing enough information? What about tour operators?
To try and answers some of these questions we interviewed a scientist working on volcanic hazard and issues related to tourism. In today post, we welcome Bradley Scott from GNS Science, New Zealand.