GeoLog

Hydrological Sciences

Imaggeo on Mondays: A lifeline between light and shadow

Imaggeo on Mondays: A lifeline between light and shadow

The Rapaälven making its way through the Rapadalen valley in Northern Sweden. After over a week of hiking through pure wilderness I reached the summit of Skierffe together with three friends. We were just blown away by the view and completely in awe for the beautiful shape of the rivers course… little lakes in between river channels of different sizes as well as dense vegetation forming a habitat for so many animals.. all controlled by erosion and the force of the water cycle…

A few days later we learned how difficult it is to hike through terrain like this for humans but how fast and quiet a moose can move right across the valley.

The Rapaälven is the biggest river in the Sarek National Park, the Swedish part of Lapland. Four smaller rivers (Smájllajåkkå, Mikkájåkkå, Guohperjåkkå, Áhkáåkkå) form this 75km long stream that drains around 30 different glaciers and the surrounding national park.

Description by Florian Konrad, as it first appeared on imaggeo.egu.eu

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/.

Conversations on a century of geoscience in Europe: Part 1

Conversations on a century of geoscience in Europe: Part 1

When you think about the last century of geoscience, what comes to mind? Perhaps Alfred Wegener’s theory of continental drift? Or Inge Lehmann’s discovery of Earth’s solid inner core?

Over the last 100 years, geoscientists have made incredible contributions to our understanding of the Earth, the solar system, and beyond. The science community has explored uncharted territory, challenged previously held conceptions, provided vital information to policymakers, worked to address societal challenges, and put forth paths for sustainability. Through the years, researchers have also worked to promote diversity, inclusion, transparency, and accessibility in the geosciences. Many Europe-based scientists have been at the forefront of these advances.

Inspired by the centennials of the American Geophysical Union (AGU) and the International Union of Geodesy and Geophysics (IUGG), which were both founded in 1919, we would like to highlight Europe’s role in shaping the geosciences and the great achievements of European geoscientists within the last century.

In this series of interviews, scientists across different disciplines and scientific fields reflect on the last 100 years of Earth, space and planetary sciences in Europe and share their perspectives on the future:


Anne-Marie Treguier: Research Director at the French National Centre for Scientific Research and the European Institute for Marine Studies in the Ocean Physics Laboratory

The responsibility of geoscientists is huge. We must frame our scientific questions in the context of a wide range of future scenarios..

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John Burrows: Professor of the Physics of the Ocean and Atmosphere and a Director of the Institutes of Environmental Physics and Remote Sensing at the University of Bremen

The history of discoveries in the geosciences is a fascinating story, involving unexpected and perplexing observations..

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Günter Blöschl: Head of the Institute of Hydraulic Engineering and Water Resources Management and Director of the Centre for Water Resource Systems of the Vienna University of Technology

As Heraclitus said, there is nothing permanent except change. Innovation needs to be permanent. We are in for an exciting future..

 

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Antje Boetius: Director of the Alfred Wegener Institute (AWI) Helmholtz Center for Polar and Marine Research and Professor of Geomicrobiology at the University of Bremen

When one reads the original reports and letters, we can learn how relevant expeditions and fieldwork were – and still are – for the international, collaborative spirit of the geosciences worldwide. The amazing thing is, in many ways we have remained explorers of our own planet Earth even today..

 

 

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Bernhard Diekmann, Head of the Research Unit Potsdam of the Alfred Wegener Institute (AWI) Helmholtz Center for Polar and Marine Research and Professor of Quaternary Geology at Potsdam University

During the last 100 years, the focus in geological research was understanding of processes in Earth’s interior and skin…The geosciences should no longer be seen as an individual field of research, but must be integrated into a holistic view of natural and social sciences..

 

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Interviews by Olivia Trani, EGU Communications Officer

Imaggeo on Mondays: Our QUEST for innovative tools to understand changing environments and climates

Imaggeo on Mondays: Our QUEST for innovative tools to understand changing environments and climates

The photo shown here shows typical sampling work underground. You can see Ola Kwiecien and Cinthya Nava Fernandez, researchers at Ruhr University Bochum in Germany, collecting dripwater in New Zealand’s Waipuna Cave as part of a four-year EU-funded monitoring programme. Our research aims at developing innovative geochemical indicators that we can use to quantify changes in the hydrological system or biosphere above the cave that result from variations in weather patterns and climate.

Caves are fantastic natural archives and laboratories. One can imagine caves like libraries of natural history: they host carbonate formations (such as stalagmites, stalactites, flowstones etc., collectively known as speleothems) which, like books, can be read by geochemists to learn about past climatic and environmental conditions. Importantly, these ‘stone books’ must, on the one hand, be protected from destruction by weathering, and on the other, must be written in a language that we can decipher. The secluded cave environment greatly helps protect speleothems from erosion and weathering, while monitoring the cave environment and hydrology allows us to learn the alphabet which nature uses to write natural history into the speleothems. Only then can we reconstruct, and ideally quantify, past environmental conditions.

Of special importance for our work in New Zealand is the El Nino-Southern Oscillation and the southern Westerlies. These two atmospheric subsystems strongly influence weather and climate in New Zealand. Southward or northward shifts of the Westerlies influence New Zealand crop yields and tourism, as well as the fishing economy, among others. El Nino and La Nina have equally strong impacts on weather patterns in New Zealand (and, in fact globally).

Despite many years of research, the mechanisms that cause changes to the ENSO and the Westerlies, and their interaction, still remain poorly understood. This lack of knowledge limits scientists’ efforts to estimate the magnitude and direction of changes that might result from ongoing global warming.

Our team of German, British and New Zealand geochemists, mathematicians, palaeoclimatologists and modellers set out to develop innovative tools and methods that would allow researchers to quantify, for example, changes in rainfall or seasonality, with the ultimate goal that these should be applicable globally. The manual sampling depicted in the photo might soon be replaced by an automatic sampler, which would greatly reduce the costs for regular fieldwork. Especially in remote settings such robots would be of great benefit for our research.

Our team also developed new proxies, such as a lignin-based (biomarker) proxy that allows us to reconstruct changes in vegetation above the cave. We also explored how transition metals behave in the hydrological system of caves, and the factors that control how these metals are transported and incorporated into speleothems. These research activities will hopefully give us powerful and very sensitive tools to quantify changes of environmental parameters, including rainfall, temperature, soil and vegetation and the underlying forcings, like ENSO. Until we have our tool kit properly calibrated, we continue our visits to Waipuna and other caves in New Zealand and Germany.

Our QUEST project has received funding from the European Union’s Horizon 2020 Research and Innovation programme and the Royal Society of New Zealand. Find more at http://quest.pik-potsdam.de/

By Sebastian Breitenbach, Ruhr University Bochum (Germany), and Adam Hartland, University of Waikato (New Zealand)

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/.

Groundwater springs harbour hidden viruses

Groundwater springs harbour hidden viruses

In many parts of Sub-Saharan Africa, groundwater springs are a vital, precious source of water. They are also a reservoir of disease. Research presented at the European Geosciences Union General Assembly in Vienna reveals that groundwater reservoirs in Ghana, Tanzania and Uganda contain diverse communities of viruses – including those that present a risk to human health.

The work, carried out by IHE Delft in the Netherlands and a number of local universities, is the first to find such extensive virus communities in groundwater. Amongst the 25 virus families found were pox and herpes viruses, responsible for a number of skin infections. Papillomavirus, which causes several types of cancer, was also present in the water. And this is just a fraction of what’s likely to be out there – other methods are likely to reveal many more, scientists involved with the new research say.

According to the new findings, the reason for this plethora of pathogens is poor sanitation in areas where freshwater percolates down from the surface and recharges the groundwater supply. Here, the viruses persist for several years before being discharged at the surface.

The virus communities were identified by extracting DNA from the groundwater. This graphic shows how they enter the groundwater and the local population. Credit: IHE Delft

Better sanitation and safe water supplies are needed to address the issue, but there aren’t always enough resources to tackle both. In areas like Kampala (Uganda) as much as 60% of the population relies on groundwater as a source of water. Simply switching to another source is not an option – there are none available.

In Accra (Ghana) and Kampala – groundwater systems are quite confined, covering an area that closely matches the distribution of the community. This means you can use a local approach to groundwater management, and develop something that works well for the communities living there.

Hydrogeolologist Jan Willem Foppen and his team take time to learn from the community, identifying pathways for the future together – an approach called transition management. Each pathway leads to small interventions, that the team can learn from. “When you work with a community and co-create knowledge, you get beautiful and unexpected results,” says Foppen.

For Foppen, the enthusiasm of the local population towards this approach is one of the most rewarding parts of the job: “we see this being replicated in other communities in Ghana and in Kampala, that is the biggest compliment we can get.”

This is still much to uncover about these virus communities. For example, scientists don’t yet know whether the viruses are dead or alive. 70% of the DNA found in the springs was unidentifiable. What’s more there is a whole separate group of viruses – RNA viruses – that haven’t even been studied yet.

By Sara Mynott, EGU Press Assistant