GeoLog

Atmospheric Sciences

Imaggeo on Mondays: counting stars

Imaggeo on Mondays: counting stars

This year’s imaggeo photo contest saw humdreds of great entries. Among the winning images was a stunning night-sky panorama by Vytas Huth. In today’s post, Vytas describes how he captured the image and how the remote location in Southern Germany is one of the few (in Europe) where it is still posssible to, clearly, image the Milk Way.

I took the image in October 2015, usually the last time of the year when it is possible to see the center of the Milky Way at night. It is a single exposure 50mm, f/1.8, iso6400, 6s and it was shot in the north-eastern German lowlands. Light pollution is little there since it is the least dense populated region of Germany with lakes and forests and clean fresh air. Many other areas of Central and Western Europe are heavily light polluted, and decent shots of the Milky Way can usually only be done high up in the mountains. Light pollution has been recognised as a problem since the early 80s and its adverse effects of light pollution affect human health, animal behavior and ecosystem functions.

However, even the area where this shot was taken is not free of light pollution, which can be seen by the orange glow at the bottom of the image resulting from nearby village lights. However, a proper amount of lighting is generally unneeded, with audits suggesting between 30-60 %. This indicates that a better managing of light not only reduces light pollution but also energy waste and greenhouse gas emissions.

Last, but not least, everyone I know loves to watch the stars. Dark night skies are a cultural heritage, that man has looked upon for thousands of years, used as a calendar to prepare sowing and harvest or to navigate ships around the world’s oceans. For these reasons I believe that it is equally important to preserve dark skies as much as other elements of nature.

To put it into Bill Watterson’s words (creator of the famous comic series Calvin and Hobbes): “If people sat outside and looked at the stars each night I bet they would live a lot differently.”

By Vytas Huth, Leibniz Centre for Agricultural Landscape Research, University of Rostock, Germany

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: A Bubbling Cauldron

Imaggeo on Mondays: A Bubbling Cauldron

Despite being a natural hazard which requires careful management, there is no doubt that there is something awe inspiring about volcanic eruptions. To see an erupting volcano up close, even fly through the plume, is the thing of dreams. That’s exactly what Jamie  Farquharson, a researcher at Université de Strasbourg (France) managed to do during the eruption of the Icelandic volcano Bárðarbunga. Read about his incredible experience in today’s Imaggeo on Monday’s post.

The picture shows the Holuhraun eruption and was taken by my wife, Hannah Derbyshire. It was taken from a light aircraft on the 11th of November of 2014, when the eruption was still in full swing, looking down into the roiling fissure. Lava was occasionally hurled tens of metres into the air in spectacular curtains of molten rock, with more exiting the fissure in steady rivers to cover the surrounding landscape.

Iceland is part of the mid-Atlantic ridge: the convergent boundary of the Eurasian and North American continental plates and one of the only places where a mid-ocean ridge rears above the surface of the sea. It’s situation means that it is geologically dynamic, boasting hundreds of volcanoes of which around thirty volcanic systems are currently active. Holuhraun is located in east-central Iceland to the north of the Vatnajökull ice cap, sitting in the saddle between the Bárðarbunga and Askja fissure systems which run NE-SW across the Icelandic highlands.

Monitored seismic activity in the vicinity of Bárðarbunga volcano had been increasing more-or-less steadily between 2007 and 2014. In mid-August 2014, swarms of earthquakes were detected migrating northwards from Bárðarbunga, interpreted as a dyke intruding to the east and north of the source. Under the ice, eruptions were detected from the 23rd of August, finally culminating in a sustained fissure eruption which continued from late-August 2014 to late-February of the next year.

My wife and I were lucky enough to have booked a trip to Iceland a month or so before the eruption commenced and, unlike its (in)famous Icelandic compatriot Eyjafjallajökull, prevailing wind conditions and the surprising lack of significant amounts of ash from Holuhraun meant that air traffic was largely unaffected.

At the time the photo was taken, the flowfield consisted of around 1000 million cubic metres of lava, covering over 75 square kilometres. After the eruption died down in February 2015, the flowfield was estimated to cover an expanse of 85 square kilometres, with the overall volume of lava exceeding 1400 million cubic metres, making it the largest effusive eruption in Iceland for over two hundred years (the 1783 eruption of Laki spewed out an estimated 14 thousand million cubic metres of lava).

Numerous “breakouts” could be observed on the margins of the flowfield as the emplacing lava flowfield increased in both size and complexity. Breakouts form when relatively hot lava, insulated by the cooled outer carapace of the flow, inflates this chilled carapace until it fractures and allows the relatively less-viscous (runnier) interior lava to spill through and form a lava delta. Gas-rich, low-viscosity magma often results in the emission of high-porosity (bubbly) lava. My current area of research examines how gases and liquids can travel through volcanic rock, a factor that is greatly influenced by the evolution of porosity during and after lava emplacement.

Flying through the turbulent plume one is aware of a strong smell of fireworks or a just-struck match: a testament to the emission of huge volumes of sulphur dioxide from the fissure. Indeed, the Icelandic Met Office have since estimated that 11 million tons of SO2 were emitted over the course of the six-month eruption, along with almost 7 million tons of CO2 and vast quantities of other gases such as HCl. These gases hydrate and oxidise in the atmosphere to form acids, in turn leading to acid rain. The environmental impact of Holuhraun as a gas-rich point source is an area of active research.

By Jamie Farquharson, PhD researcher at Université de Strasbourg (France)

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

GeoPolicy: 8 science-based projects improving regions in the EU

GeoPolicy: 8 science-based projects improving regions in the EU

As scientists, it can sometimes be difficult to see the real-world implications of some of our research. Concepts can often seem abstract and remote when sitting in a lab or taking field measurements. But researching the Earth sciences can have profound effects on global society. Understanding how the natural world works can help protect and improve human, animal, and plant life. This month’s GeoPolicy post (part of the European Geosciences Union GeoLog Blog) highlights EU funded projects that have their foundations in the Earth sciences.

EU member states can apply for regional project funding that aims to improve living standards for the residents living within that region. Projects can be technology, medicine, environment, or social-science based. This post highlights 8 projects that have resulted from earth-science research. Scroll down to see what projects are going on in your country, or your area of science. A full list of EU funded projects can be found here and more information on the EU regional development fund can be found on their website.

 

Preventing coastal erosion in Southern France

Coastal erosion causes coastlines to collapse and retreat landward. This can have damaging effects on local residents, or on those who use the coast for recreational activities. In the Mediterranean, beaches are sustained by sediment supplied from river deltas. Erosion can occur when less river sediment is transported to the coasts. This can occur when there has been a decrease in the frequency of major floods, catchment reforestation, dam construction, or dredging activities1.

The EU funded a project to protect coastal regions in the South of France; an area popular for tourists and local residents alike. Amongst other initiatives, which included infrastructure changes, a dune ridge was re-established to protect the beach and coastal area.

http://ec.europa.eu/regional_policy/en/projects/france/preservation-of-coastal-gem

 

River adaptation to fight flash floods in Spain

The Simat region, located on the East coast of Spain, near Valenciana, is often subjected to flash flooding as it is situated between mountains and the Mediterranean Sea. Flash floods caused by heavy autumn rains burst river banks and have a devastating effect on the surrounding villages.

EU funding provided both ‘soft’ and ‘hard’ flood defences for the Valenciana region. Soft river defences use natural resources and local knowledge to protect residents from flooding. A region upstream of Simet was reclaimed for flood plains and the river was widened. To complement this, a canal system (an example of a hard defence strategy) was constructed further downstream.

http://ec.europa.eu/regional_policy/en/projects/spain/river-adaptation-to-fight-flash-floods

 

Energy Efficiency: Recovering heat to produce thermal energy in Greece

Increasing energy efficiency is a key objective for the European Union: there is a specific EU Directive that focuses entirely on improving energy usage. By 2020, the EU aims to have saved roughly the equivalent of 400 power stations-worth of energy2.

Florina, a city in mainland Greece, has been awarded EU funding for a project aimed to distribute unused heat energy from power stations to 23,000 local residents. Surplus heat will be piped as ‘superheated water’ to local homes and businesses. As well as improving energy efficiency, this project is expected to cut water-related greenhouse gas emissions by 88%, as hot water will no longer be heated by traditional oil and gas combustion methods.

http://ec.europa.eu/regional_policy/en/projects/greece/recovering-heat-to-produce-thermal-energy

 

Improving groundwater quality in Poland

Groundwater is a lifeline to supplying Europe with freshwater. Over 300 million EU citizens get their drinking water from these subsurface water deposits. Unfortunately, groundwater can become contaminated making it unfit to be consumed, and endanger aquatic and terrestrial ecosystems. This can happen when septic systems that are not connected to modern sewer systems leak bacteria, viruses, and chemicals into the environment.

An EU funded project for the Poznań region in Poland is protecting local groundwater supplies by improving wastewater treatment networks, which will benefit almost 736,000 local inhabitants. The construction of an integrated water and wastewater monitoring system helps to protect residents as well as the surrounding ecosystems.

http://ec.europa.eu/regional_policy/en/projects/poland/improving-groundwater-quality-around-poznan

 

Micro-hydropower plants in the UK and Ireland

The world needs to shift to non-carbon based energy generation to reduce greenhouse gas emissions. The EU aims to achieve 20% energy generation from renewable sources by 2020 (2012 levels stood at 11%)3. Renewable energy sources include hydropower, geothermal, wind energy, solar energy, and biomass. Hydropower is commonly generated through dam structures, where flowing water passes through a turbine. An alternative method is to take surplus electrical energy from the grid and use it to pump water to elevated ground, therefore storing it as potential energy to be used later.

A common method within water supply systems is to use pressurised pumps to transport water to the pipeline network. Excess pressure is often vented, releasing unused energy into the atmosphere. A recently funded EU project aims to create hydro-energy from these supply systems by installing micro-hydropower plants on the ventilation valves. The generated electricity can be used to reduce conventional energy consumption. The project has been funded for regions in Wales and Ireland, however it is thought this technology could be expanded across Europe and beyond.

http://ec.europa.eu/regional_policy/en/projects/europe/retrieving-water-energy-at-micro-hydropower-plants-could-pave-the-way-to-more-sustainable-water-supply-systems-in-ireland-and-wales

 

Turning copper to gold: mining in Portugal

Raw materials, including minerals and rare-earth elements, are used in infrastructure, renewable energy resources, agriculture, and telecommunications. The vast majority of these resources are imported to the EU, and very few mineral mines are located within Europe. It is important to improve the security of supply by either increasing internal supply or reducing the need for these materials.

The Alentejo region in Portugal is located on the Iberian pyrite belt, a geological zone rich in mineral deposits. Mining has occurred for many centuries and the region currently employs over 500 people. Funds have been awarded to develop the mine’s capabilities to increase its output of copper ore, whilst continuing to meet EU environmental standards.

http://ec.europa.eu/regional_policy/en/projects/portugal/turning-copper-to-gold

 

Adapting water management to climate change in Denmark and Germany

Greenhouse gases absorb radiated energy from the Earth and re-radiate this as heat; raising global temperatures. This results in ice caps and glaciers melting and causes rising sea levels. Low-lying countries are now experiencing greater flooding episodes and increasing storm surges (another effect of manmade climate change). The Syddanmark region in Denmark and the Schleswig-Holstein region in Germany was awarded EU funding to assess and reduce the damage new flooding has on these areas. After discussions with professionals, politicians and members of the public, it was decided to develop a hydrological model to assess the future impacts flooding would have. The model was able to highlight where dikes should be relocated and retention areas be created to reduce negative flooding impacts. Additionally, the resulting changes showed positive biodiversity effects in these new areas from the temporary flooding.

http://ec.europa.eu/regional_policy/en/projects/europe/grenzwasser-adapts-water-management-to-climate-change-requirements

 

Establishing a commercial spaceport in Sweden

Space research and exploration does more than simply try to answer overarching questions about life, the solar system, and beyond. The research and development driven by space science and exploration have led to inventions that are now used to help us in our daily lives. The ESA has a portfolio of ~450 inventions, covering areas such as optics, robotics, and electrical power. The development of the so-called “second space age” is seeing private space companies contributing to research and innovation, as well as providing opportunities for more commercial space flights.

The Kiruna region, in Northern Sweden, established an international space and research ground-station over 50 years ago. The station hosts rocket and balloon launches, satellite monitoring, new space and flight systems testing, and multiple ground-based space measurements. A project has been funded to transform the Kiruna centre into a ‘fully functioning spaceport’ to develop new products, services, research, and education.

http://ec.europa.eu/regional_policy/en/projects/best-practices/sweden/2105

 

More information about EU project funding and where it is allocated can be found on the European Commission website.

 

Sources:

1 – http://www.climatechangepost.com/france/coastal-erosion/

2 – https://ec.europa.eu/energy/en/topics/energy-efficiency

3 – http://www.eea.europa.eu/soer-2015/europe/energy

 

Volcanic darkness marked the dawn of the Dark Ages

Volcanic darkness marked the dawn of the Dark Ages

The dawn of the Dark Ages coincided with a volcanic double event – two large eruptions in quick succession. Combined, they had a stronger impact on the Earth’s climate than any other volcanic event – or sequence of events – in the last 1200 years. Historical reports reveal that a mysterious dust cloud dimmed the sun’s rays between in 536 and 537 CE, a time followed by global societal decline. Now, we know the cause.

By combining state-or-the-art ice core measurements with historical records and a climate model, researchers from GEOMAR Helmholtz Centre for Ocean Research, Germany, and a host of international organisations showed that the eruptions were responsible for a rapid climatic downturn. The findings, published in Climatic Change, were presented at the EGU General Assembly in April 2016.

Explosive volcanic eruptions typically emit large volumes of ash and gas high into the atmosphere. The way this ash spreads depends both on how high up it’s propelled and the prevailing weather conditions. When it reaches the stratosphere, it has the capacity to spread far and wide over the Earth, meaning the eruption will have much more than a local impact.

Individually, these events were strong, but not that strong. Their combined force was what made their affect of the earth’s climate so significant. They occurred closely in time and were both in the Northern hemisphere.

Volcanic emissions reflect light back into space. Consequently, less light and, importantly, less heat reaches the surface, causing the Earth to cool. Diminishing sunlight following the eruptions resulted in a 2 °C drop in temperature, poor crop yields and population starvation. The drop in temperature led to a 3-5 year decline in Scandinavian agricultural productivity – a serious problem.

This double event had a major impact on agriculture in the northern hemisphere – particularly over Scandinavia. It’s likely that societies could withstand one bad summer, but several would have been a problem.

An ash covered plant via Wikimedia Commons.

An ash covered plant via Wikimedia Commons.

There’s agricultural evidence to support the theory too. Pollen records read from sediment cores can be used to work out when agricultural crops covered the land and when the land was ruled by nature. Scandinavian cores suggest there was a shift from agricultural crops to forest around the time of the eruption. There is some scepticism regarding the cause of this shift, but the implication is that when food decreases, so does the population, This means there’s no need to farm as much land, nor enough people to do so. In the absence of agriculture, nature takes over and trees once again cover the land.

By Sara Mynott, EGU Press Assistant and PhD candidate at the University of Exeter.

Sara is a science writer and marine science PhD candidate from the University of Exeter. She’s investigating the impact of climate change on predator-prey relationships in the ocean, and was one of our Press Assistants this year’s General Assembly.

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