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Another (surprising) brick in the wall: how seagrass protects coastlines against erosion.

Another (surprising) brick in the wall:  how seagrass protects coastlines against erosion.

Dear readers, today our blog will host Marco Fusi, a postdoctoral fellow working on coastal ecosystems. Together with Marco we will give a twist to our usual geoscientific perspective and mix some ecology in it. Specifically, we will explore the surprising role of seagrass in limiting coastal erosion effects.

Marco Fusi is a Post-Doctoral Researcher at KAUST (Saudi Arabia), since 2014. He graduated at University of Milan (Italy) with a Ph.D. in tropical ecology. His primary interest focuses on ecological connectivity and interactions in coastal ecosystems.

1- Hello Marco, please give us an overview of coastal erosion issues.

When we speak about coasts, we think about beautiful mangrove forests or a dream tropical coastline that harbours beautiful crystal water where to dive in the middle of coral reefs. However, we tend to forget that coasts are inhabited by almost 3 billion of people all over the world and hundreds of kilometres of coastline are heavily constructed. Cities, resorts, villages are expanding along the coast worldwide and often, the risk of coastal erosion is not considered. In the lasts decades, inland anthropogenic management resulted in a limited input of sediment to the sea and therefore the marine current started to erode beaches and rocky shore resulting sometimes in dramatical destruction of buildings.

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Combining geomorphology, geomorphometry and natural hazards research: the way forward

Combining geomorphology, geomorphometry and natural hazards research: the way forward

Today I have the honour to introduce a friend and a brilliant scientist that recently won the 2019 Arne Richter Award for Outstanding Early Career Scientists of the EGU, Dr Giulia Sofia. Dr Sofia is currently Assistant Research Professor at the University of Connecticut (USA) in the Hydrometeorology and Hydrologic Remote Sensing group. She received a B.S. and M.S. in Forestry Science, and PhD (2012) in Water Resources, Soil Conservation & Watershed Management from the University of Padova (Italy). Her area of research is geomorphology and digital terrain analysis, with a special interest in feature extraction from high-resolution topography. Her recent research interest concerns anthropogenic landscapes, incorporating the related human-induced processes. Her interdisciplinary research background is the reason behind today interview, to shed some light on the interrelation that geomorphology has with natural hazard research.

1. Hello Giulia. Can you please tell us what geomorphology and geomorphometry are?

Think about looking at a landscape, and working out how each earth surface process, such as air, water, and ice, can mould it. Think about piecing together the history and life of such a landscape place by studying landforms and sediments, and how they interact(ed). Well, this is geomorphology: the science of landforms, their processes, forms and sediments at the surface of the Earth, and sometimes other planets. Geomorphometry, on the other hand, is the science of quantitative land-surface analysis. It draws upon mathematics, computer vision, machine learning, image-processing techniques and statistics to quantify the shape of earth’s topography at various spatial and temporal scales. [Read More]

The (un)usual suspect: how the environment affects human health.

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.

A photo portrait of Dr. Ines Tomašek

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.

 

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Volcanic eruptions: Sometimes natural spectacles, but other times disasters

In April 2018, an eruption of the Kilauea volcano in Hawaii started. The activity continued for months, with impressive lava flows that cut roads and even covered houses and entire neighbourhoods (Figure 1), forcing the evacuation of thousands of people. Fortunately, it did not take any life. Some weeks later, on June 3rd,  Fuego volcano, in Guatemala, shocked the international community with a shorter, but certainly more violent, eruption. The eruption of Fuego volcano, probably less known than Kilauea, affected near two millions of people and sadly caused 190 verified deaths and 238 missing persons.

 

Figure 1. Comparison of satellite images before (left) and after (right) the Kilauea eruption at Leilani Estates subdivision, Hawaii. The area was covered by lava flows. Image credit: USGS.

The main reason why Fuego’s eruption was more deadly than the Kilauea’s one is the type of activity. They are different types of volcanoes with different eruptive dynamics and thus different related hazards. Kilauea is a shield volcano and it is formed by a sequence of eruptions of very low viscous magma. The magma reaches the surface and is generally erupted in an effusive way generating lava flows, really hot mixtures of molten rock, crystals and gas emitted from the volcanic vent, able to reach several meters per second  and kilometers of length, literally looking like rivers (such as in this video). These lava flows can be sometimes accompanied by weak to mild explosive activity in the form of lava fountains. [Read More]