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Natural Hazards

natural hazard

Let the ash fall, but get ready for its consequences

Let the ash fall, but get ready for its consequences

The past 18th May marked 39 years since one of the most emblematic volcanic eruptions in historic times: the 1980 Mt St Helens explosive eruption. With a death toll of 57 victims, it is the deadliest volcanic event in U.S. history. If that wasn’t enough, it also destroyed hundreds of houses and roads. When we think about explosive volcanic eruptions what commonly comes in our minds about the possible related hazards are impressive Pyroclastic Density Currents (PDC) or Lahars (a glossary below), mainly because of their quick deadly potential, moving ashfall to a secondary role in producing hazards to population.

However, ashfall can be hazardous too even affecting people’s health in the long term and in distal areas from the volcano itself. In today’s post, we will go through how the fall of volcanic ash can be a hazard that must be taken into account by people living in the close (and sometimes not-too-close) neighbourhood of an active volcano. [Read More]

The CRED presents the bill: the socio-economic cost of natural disasters.

The CRED presents the bill: the socio-economic cost of natural disasters.

Which type of natural disaster is the most frequent? And which one causes the largest economic losses? Which populations are mainly affected? What are the necessary steps to reduce natural disasters’ impact? If you have ever wondered about any of these questions, you’d be interested to know that there is an institute answering all of them with a series of reports and ad hoc publications.

We are talking about the Centre for Research on the Epidemiology of Disasters (CRED). The CRED is based, since 1973, at the Université Catholique de Louvain in Belgium and since 1980 it’s a collaborator of the World Health Organization (WHO). Their main goal? Study public health during a mass emergency as well as the structural and socio-economic impact of natural and technological disasters and human conflicts. They maintain the world’s most comprehensive database (EM-DAT) on occurrence and effects of technological and natural disasters from 1900 to the present day: more than 22,000 events and counting. [Read More]

The collapse of Anak Krakatau volcano: a scenario envisaged

The collapse of Anak Krakatau volcano: a scenario envisaged

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.

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Heavy metals in industrial wastewater: hazardous waste or secondary resource?

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.

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