GeoLog

GeoLog

Imaggeo on Mondays: The breath of our Earth

Imaggeo on Mondays: The breath of our Earth

This picture was taken in the Myvatn geothermal area in southeast Iceland. Seeing the geothermal steam vent in this area while the temperature was -22 degrees Celsius is the best experience in Myvatn. The difference between Iceland’s cold ambient temperature and the released heat from inside the Earth is a really stunning event to see.

Iceland is situated in the middle of two tectonic plates (the Eurasian and North American plates) that, through their movement, have led to more than a hundred active and inactive volcanoes in this country. Due to the region’s high volcanic activity and shallow magma chambers, the temperature below Iceland’s surface is generally higher than that of continental areas without volcanoes. These conditions are responsible for the country’s high production of geothermal energy.

This heat can reach the surface in one of two ways. First, heat can naturally escape from the heart of Earth through cracks on the Earth’s surface itself. Second, geothermal powerplants can insert pipes far below the Earth’s surface to capture this heat.

Iceland is known for its geothermal spas, like the famous Blue Lagoon,  but additionally, Icelanders use geothermal energy as their main source of heating; in winter, almost 100 percent of the nation’s heating comes from geothermal energy. In the country’s capital Reykjavik, much of the city’s main roads are heated by this source, keeping the streets free from ice and snow. Geothermal energy also accounts for about 25 percent of the island’s electricity.

How is geothermal energy produced? As a heating source, geothermal power plants use a heat exchanger, a pipe that converts the hot water inside the earth into heat. It is then distributed within the steam pipe to residential areas. As an electricity source, power plants capture steam or hot water from geothermal areas to drive electricity generators. The machines convert the heat into electricity, which is then shared with Icelandic neighborhoods.

Because of its investment in a renewable energy source, Iceland is well known as a global leader in sustainability.

By Handriyanti Diah Puspitarini, University of Padova, Italy

GeoTalk: A new view on how ocean currents move

GeoTalk: A new view on how ocean currents move

Geotalk is a regular feature highlighting early career researchers and their work. In this interview we speak to Jan Zika, an oceanographer at the University of New South Wales in Sydney, Australia. This year he was recognized for his contributions to ocean dynamics research as the winner of the 2018 Ocean Sciences Division Outstanding Early Career Scientists Award.

First, could you introduce yourself and tell us a little more about your career path so far?

My pleasure. I was actually pretty set on the geosciences as a kid. I think all my projects in my last year of primary school were about natural disasters of some form or another – volcanoes, earthquakes, tsunamis, etc. My teachers must have thought I was going to grow up to be a villain in a James Bond film.

I grew up in Tasmania, where there aren’t exactly natural disasters, but nature was very present in my everyday life and that sustained my interest into adulthood. When I was ready for university, meteorologists, geologists, and other researchers advised me to do the hard stuff first. So in my undergraduate degree I focused on mathematics and physics. I was good at it, but I kind of forgot why I was there at some point.

Things changed for me when I interned at a marine science laboratory in Hobart operated by the Commonwealth Scientific and Industrial Research Organisation (CSIRO). I’d walked past the building so many times growing up but never thought I’d get to work inside. Bizarrely, I worked on a project related to the Mediterranean Sea. It was just so uplifting being able to put all these skills I had learnt in class, like vector calculus and thermodynamics, into practice.

From then on I was properly hooked on oceanography and the geosciences. I got into a PhD program through the CSIRO, which felt like being drafted to the Premier League. After completing the doctorate, I took a job as a research fellow in Grenoble, France. Not an obvious place to study the ocean I know, but there was a great little team there. After a couple of years, I moved to the UK, first to the University of Southampton then Imperial College London.

After seven years as a research fellow in Europe I returned home to Australia to become, of all things, a mathematics lecturer at the University of New South Wales. My research is still related to oceans and climate, but day-to-day I am teaching maths. At least now when I teach vector calculus I can pepper the lectures with the sorts of applications to the natural world that have inspired me throughout my whole career.

This year you were awarded an Outstanding Early Career Scientists Award in the Ocean Sciences Division at the 2018 General Assembly for you work on understanding the ocean’s thermohaline circulation and its role in Earth’s climate. Could you tell us more about your research in this field and its importance?

I’d love to. In many fields of science just changing the way you look at a problem can have a big effect. Usually this involves drawing different kind of diagrams. These diagrams may seem abstract at first, but eventually they make things easier to understand. Some diagrams we are all familiar with in one way or another, such as the periodic table, Bohr’s model of the atom, and the economists’ cost-benefit curve. These were all, at some stage, new and innovative ways of presenting something fundamentally complex. I am not saying I did anything like make a model for the atom, but I was inspired by the work of 19th century physicists who made simple diagrams to describe thermodynamic systems (like engines and refrigerators, for example). I wanted to apply these types of ideas to the ocean.

Working closely with colleagues in Australia and Sweden, I came up with a way to make a new diagram for the ocean’s thermohaline circulation. This is the circulation that, in part, makes Europe relatively warm, and plays a big role in regulating Earth’s climate. The new diagram we developed helped us to understand the physical processes controlling the thermohaline circulation and opened the door to all sorts of new methods for understanding the ocean’s role in climate.

Jan’s diagram of ocean circulation in temperature-salinity coordinates from a global climate model (Community Earth System Model Version 1). Contours represent volumetric streamfunction in units of Sverdrups (1Sv = 10^6 m^3 s^-1). Credit: Jan Zika

I started to realize I had stumbled onto something really big when I ran the idea by a Canadian colleague Fred Laliberte, who was a researcher at the University of Toronto at the time. He had been working on a very similar problem in the atmosphere, and my diagram was just the thing he needed to work things out. We ended up getting that work published in the journal Science and we were able to say a thing or two about how windy the world might get as the climate changes. To know my ideas were having an impact well beyond my immediate research area really was special.

And what did you find out? How will climate change affect the world’s wind?  

What we found was that overall the earth’s atmosphere won’t get much more energetic (or may even get less energetic) as the climate warms. This means that although extreme storm events may become more frequent in the future, weak storms may become much less frequent (more calm weather). One can draw an analogy with a spluttering engine: it produces bursts of energy when it splutters but is slower and less effective the rest of the time.

Your research pursuits have taken you to some pretty incredible places. What have been some highlights from your time out in the field?

It has been great to balance the mathematics and theory I do with research in the field. As an oceanographer I have been ‘to sea’ a few times. The most memorable was when I was part of a research project to measure in the Southern Ocean. Our research area was between South America and the Antarctic continent. We set off from the Falkland/Malvinas Islands and made our way around the Scotia Sea dropping by South Georgia on our way back. Those Antarctic islands had the most spectacular scenery I have ever seen. The highlight though was when a gigantic humpback whale spent a few hours playing with us and the ship – spinning under water, breaching and popping up to say hello.

Jan (right) with Brian King (left) from the UK National Oceanography Centre. Pictured here on the James Clarke Ross in the South Atlantic deploying an Argo Float. The instrument measures ocean temperature, salinity and pressure. Credit: Jan Zika

As part of the research, we released a small amount of inert substance (a type of chemical that wouldn’t affect marine life) about a kilometre below the surface of the ocean. This is called a ‘tracer.’ The idea was we would let the ocean currents move and stir the substance like milk poured into coffee. It is really important for us to understand how much things mix in the deep ocean as this affects the thermohaline circulation and how heat and carbon are absorbed into the ocean with global warming.

Once we had released the substance it wasn’t that easy to find where it had gone. What we had to do was float around, drop over an instrument that could trap water at different depths, then bring the water samples to the surface and analyse them in a small lab we had on board. The difficult part was the tracer would become really dilute once it had been mixed by ocean currents, and it was both a really time consuming and costly process to collect and analyse the substance. So we had to exploit sophisticated computer models and pool all our knowledge and best guesses on where the tracer might have gone. We did such a good job tracking it that we were able to continue gathering oodles of valuable data for almost twice as long as had originally been planned. This was testament to the excellent teamwork and ingenuity of our collaborators at sea, in the lab and in front of computers.

Outside of research, you have also been involved with a number of science communication initiatives and outreach activities with young students. What advice would you impart to scientists who would like to engage with public audiences?

That is right, I really enjoy inspiring the next generation and getting non-science folk engaged in what we do. I would say that you want to simplify things but don’t dumb them down. I’ve learnt the hard way that even when speaking to other ‘experts’ it is best to use plain language instead of jargon and go slowly through concepts even if you feel they should be basic. I think working with people from around the world (e.g. in France) who don’t have English as a first language, really helped me with this.

Jan teaching a Geophysical Fluid Dynamics class at the University of New South Wales with the aid of a rotating tank experiment. Credit: Susannah Waters

At the same time I am always surprised at how quickly young students can absorb ideas and throw up questions that even an expert wouldn’t have come up with. The great thing is that your students aren’t wedded to dogma like experienced researchers are, and so are capable of much more creative ideas.

The other day I was helping with a special event to encourage females to enter mathematics. I was inspired by a talk given by the Australian Girl’s Maths Olympiad Team who had just competed in Venice. They said solving Maths Olympiad problems was all about breaking down a big problem into smaller problems they already know how to solve. I ended up changing my own talk as I was inspired by this theme.

I guess what I am suggesting is, if you are organising outreach activities, instead of thinking about how to ‘tell them’ how things work, think about ways to get ideas from them. Include them in the process. Ask them the hard questions. That way everyone will be much more involved. And who knows, it might spark a great idea.

Interview by Olivia Trani, EGU Communications Officer

Geosciences Column: Landslide risk in a changing climate, and what that means for Europe’s roads

Geosciences Column: Landslide risk in a changing climate, and what that means for Europe’s roads

If your morning commute is already frustrating, get ready to buckle up. Our climate is changing, and that may increasingly affect some of central Europe’s major roads and railways, according to new research published in the EGU’s open access journal Natural Hazards and Earth System Sciences. The study found that, in the face of climate change, landslide-inducing rainfall events will increase in frequency over the century, putting central Europe’s transport infrastructure more at risk.  

How do landslides affect us?

Landslides that block off transportation corridors present many direct and indirect issues. Not only can these disruptions cause injuries and heavy delays, but in broader terms, they can negatively affect a region’s economic wellbeing.

One study for instance, published in Procedia Engineering in 2016, examined the economic impact of four landslides on Scotland’s road network and estimated that the direct cost of the hazards was between £400,000 and £1,700,000. Furthermore the study concluded that the consequential cost of the landslides was around £180,000 to £1,400,000.

Such landslides can have a societal impact on European communities as well, as disruptions to road and railway networks can impact access to daily goods, community services, and healthcare, the authors of the EGU study explain.

Modelling climate risk

To analyse climate patterns and how they might affect hazard risk in central Europe, the researchers first ran a set of global climate models, simulations that predict how the climate system will respond to different greenhouse gas emission scenarios. Specifically, the scientists ran climate projections based on the Intergovernmental Panel on Climate Change’s A1B socio-economic pathway, a scenario defined by rapid economic growth, technological advances, reduced cultural and economic inequality, a population peak by 2050, and a balanced reliance on different energy sources.

They then determined how often the conditions in their climate projections would trigger landslide events specifically in central Europe using a climate index that estimates landslide potential from the duration and intensity of rainfall events. The index, established by Fausto Guzzetti of National Research Council of Italy and his colleagues, suggests that landslide activity most likely occurs when a rainfall event satisfies the following three conditions: the event lasts more than three days, total downpour is more than 37.3 mm and at least one day of the rainfall period experiences more than 25.6 mm.

The researchers also incorporated into their models data on central Europe’s road infrastructure as well as the region’s geology, including topography, sensitivity to erosion, soil properties and land cover.

Overview of a particularly risk-prone region along the lowlands of Alsace and the Black Forest mountain range: (a) location of the region in central Europe and median of the increase in landslide-triggering climate events for (b) the near future and (c) the remote future.

The fate of Europe’s roadways

The results of the researchers’ models suggest that the number of landslide-triggering rainfall events will increase from now up until 2100. Their simulations also find while that these hazardous rainfall events slightly increase in frequency between 2021 and 2050, the number of these occurrences will be more significant between 2050 and 2100.  

While the flat, low-altitude areas of central Europe will only experience minor increases in landslide-inducing rainfall activity, regions with high elevation, like uplands and Alpine forests, are most at risk, their findings suggest.

The study found that many locations along the north side of the Alps in France, Germany, Austria and the Czech Republic may face up to seven additional landslide-triggering rainfall events as our climate changes. This includes the Vosges, the Black Forest, the Swabian Jura, the Bergisches Land, the Jura Mountains, the Northern Limestone Alps foothills, the Bohemian Forest, and the Austrian and Bavarian Alpine forestlands.

The researchers go on to explain that much of the Trans-European Transport Networks’ main corridors will be more exposed to landslide-inducing rainfall activity, especially the Rhine-Danube, the Scandinavian-Mediterranean, the Rhine-Alpine, the North Sea-Mediterranean, and the North Sea-Baltic corridors.

The scientists involved with the study hope that their findings will help European policy makers make informed plans and strategies when developing and maintaining the continents’ infrastructure.  

Uploading your 2018 General Assembly presentation

Uploading your 2018 General Assembly presentation

This year it is, once again, possible to upload your oral presentations, PICO presentations and posters from EGU 2018 for online publication alongside your abstract, giving all participants a chance to revisit your contribution  hurrah for open science!

Files can be in either PowerPoint or PDF format. Note that presentations will be distributed under the Creative Commons Attribution 4.0 License. Uploading your presentation is free of charge and is not followed by a review process. The upload form for your presentation, together with further information on the licence it will be distributed under, is available here. You will need to log in using your Copernicus Office User ID (using the ID of the Corresponding Author) to upload your presentation.

Presentations and posters will be linked to their corresponding abstracts. If your presentation didn’t have an abstract (this is the case for short courses and others), but you still want to share it with the wider community you can consider uploading your presentation to slideshare or figshare as a PDF to share it instead.

All legal and technical information, as well as the upload form, is available until 17 June 2018 at: http://meetingorganizer.copernicus.org/egu2018/abstractpresentation