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Geoscience hot topics – The finale: Understanding planet Earth

Geoscience hot topics – The finale: Understanding planet Earth

What are the most interesting, cutting-edge and compelling research topics within the scientific areas represented in the EGU divisions? Ground-breaking and innovative research features yearly at our annual General Assembly, but what are the overarching ideas and big research questions that still remain unanswered? We spoke to some of our division presidents and canvased their thoughts on what the current Earth, ocean and planetary hot topics will be.

Because there are too many to fit in a single post we’ve brought some of them together in a series of posts which will tackle three main areas. The first post focused on the Earth’s past and its origin, while the second post focused on the Earth as it is now and what its future looks like. Today’s is the final post of the series and will explore where our understanding of the Earth and its structure is still lacking. We’d love to know what the opinions of the readers of GeoLog are on this topic too, so we welcome and encourage lively discussion in the comment section!

A new, modern, era for research

That we have great understanding of the Earth, its structure and the processes which govern how the environment works, is a given. At the same time, so much is still unknown, unclear and uncertain, that there are plenty of research avenues which can help build upon, and further, our current understanding of the Earth system.

By Camelia.boban (Own work) [CC BY-SA 3.0], via Wikimedia Commons

Big Data’s definition illustrated with text. Credit: Camelia.boban (Own work) [CC BY-SA 3.0], via Wikimedia Commons

As research advances, so do the technologies which allow scientist to collect, store and use data. Crucially, the amount of data which can be collected increases too, opening avenues not only for scientists to carry out research, but for the wider population to be involved in scientific research too: the age of Big Data and Citizen Science is born.

The structure of the Earth

Despite a long history of study, including geological maps, studies of the structure of the Alps, and the advent of analogue models some 200 years ago, there is much left to learn about how geological processes interact and shape our Earth.

Some important unanswered questions in the realm of Tectonics and Structural Geology (TS) include:

“Why do some passive margins have high surface topography (take Norway, or Southeastern Brazil as an example) even millions of years after continental break-up? How does subduction, the process by which a tectonic plate slides under another, begin? And how does the community adapt to new research methods and ever growing datasets?” highlights Susanne Buiter, TS Division.

One important problem is that of inheritance and what role it plays in how plate tectonics work. Scientists have known, since the theory was first proposed in the 1950s (although it only became broadly accepted in the 1970s), that our planet is active: its outer shell is divided into tectonic plates which slide, collide, pull away and sink past one another. During their life-time the tectonic plates interact with surface process and eventually flow into the mantle below. This implies that any new tectonic processes will take place in material that carries a history.

“It is increasingly recognised that tectonic events do not act on homogenous, pristine materials, but more likely on crust that is cross-cut by old shear zones, incorporates different lithologies and which may have inherited heat from previous deformation events (such as folding),” explains Susanne.

So the key is: what is the impact of historical inheritance on tectonic events? Can old structures be reactivated and if so, when are they reactivated and when not? Do the tectonic processes control the resulting structures or is it the other way around?

Seismology too can shed more light on how we understand Earth processes and the structure of the planet.

“An emerging field of research is seismic super-resolution: a promising technique which allows imaging of the fine-scale subsurface Earth structure in more detail than has been possible ever before,” explains Paul Martin Mai, President of the Seismology (SM) Division.

The methodology has applications not only for our understanding of the structure and process which take place on Earth, but also for the characterisation of fuel reservoirs and identification of potential underground storage facilities. That being said, the technique is still in its infancy and more research, particularly applied to ‘real’ geological settings is needed.

Understanding natural hazards

The reasons to pursue further understanding in this area are diverse and wide-ranging: amongst the most relevant to society is being able to better comprehend and predict the processes which lead to natural disasters.

Earthquake 1920 (?). Credit: Konstantinos Kourtidis (distributed via imaggeo.egu.eu)

Earthquake 1920 (?). Credit: Konstantinos Kourtidis (distributed via imaggeo.egu.eu)

It goes without saying that, due to their destructive nature, earthquakes are a topic of continued cross-disciplinary scientific research. Generating more detailed images of the Earth’s structure, using seismic super-resolution for instance, can also improve our understanding of how and why earthquakes occur, as well as helping to determine large-scale fault behaviour.

And what if we could crowd source data to help us understand earthquakes better too? LastQuake is an online tool, operated via Twitter and an app for smartphones which allows users to record real-time data regarding earthquakes. The results are uploaded to the European-Mediterranean Seismological Centre (EMSC) website where they offer up-to-data information about ongoing shake events. It was used by over 8000 people during the April 2015 Nepal earthquakes to collect eyewitness observation, including geo-located pictures, testimonies and comments, in the immediate aftermath of the earthquake.

In this setting, citizens become scientists too. They contribute data, by acquiring it themselves, which can be used to answer research questions. In the case of LastQuake, the use of the data is immediate and can contribute towards easing rescue operations and alerting citizens of dangerous areas (for instance where buildings are at risk of collapse) providing a two-way communication tool.

Global temperatures and climate change

It is not only earthquakes that threaten communities. Just as destructive can be extreme weather events, such as typhoons, cyclones, hurricanes, storm surges, severe rainfalls leading to flooding or droughts. With the increased frequency and destructiveness of these events being linked to climate change understanding global temperature fluctuations becomes more important than ever.

Flooded Mekong. Credit: Anna Lourantou (distributed via imaggeo.egu.eu)

Flooded Mekong. Credit: Anna Lourantou (distributed via imaggeo.egu.eu)

Over periods of months, years and decades global temperatures fluctuate.

“Up to decades, the natural tendency to return to a basic state is an expression of the atmosphere’s memory that is so strong that we are still feeling the effects of century-old fluctuations,” says Shaun Lovejoy, President of the Nonlinear Processes Division (NP).

Harnessing the record of past-temperature fluctuations, as recorded by the atmosphere, can provide a more accurate way to produce seasonal forecasts and long-term climate predictions than traditional climate models and should be explored further.

Geoscience hot topics

Be it studying the Earth’s history, how to sustainably develop our communities, or simply understanding the basic principles which govern how our planet – and others – operates, the scope for avenues of research in the geosciences is vast. Moreover, the advent of new technologies, data acquisition and processing techniques allow geoscientists to explore more complex problems in greater detail than was ever possible before. It’s an exciting time for geoscientific research.

By Laura Roberts Artal in collaboration with EGU Division Presidents

Imaggeo on Mondays: Science in action – how will climate change affect Central Europe?

Imaggeo on Mondays: Science in action – how will climate change affect Central Europe?

The effects of a warming climate are expected to be far reaching. Sea-level rise, and how it will affect costal settlements make regular headlines, and not without reason. However, climate change may have other less obvious but equally dangerous impacts; for example, take a look at this recent piece highlighting the increased risk of storms and droughts in mainland Europe.

The area of Saxony-Anhalt, in northern Germany, has a rich cultural, historical and natural heritage, which is coming under threat of ever rising global temperatures, with summer drought conditions expected to be aggravated in the coming years. This is precisely where the The Helmholtz Centre for Environmental Research (UFZ) has focused some of its most recent research efforts.

Central to the discussion is to understand how the soils and local vegetation of Saxony-Anhalt will respond to the stress caused by increasingly dry conditions. Today’s imaggeo on Monday image, (curtesy of André Künzelmann, a researcher at UFZ), captures the installation of an Eddy Covariance Tower – used by scientists to acquire data which will help them understand how changing climate conditions impact the local landscape and vice versa.

Instruments on an Eddy Covariance Tower measure wind components and trace gases at high frequency to determine the exchange of e.g. carbon dioxide and methane gases which can have a high impact on climate change. In addition, meteorological data such as solar radiation, air temperature and wind are acquired as these are the main drivers of the biological processes involved in the carbon and water budgets of ecosystems.

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/.

 

Floods and droughts set to increase due to climate change

Floods and droughts set to increase due to climate change

The planet is set to encounter a record-level amount of floods and droughts by 2050 – researchers recently announced at the European Geosciences Union’s General Assembly in Vienna. Nikita Marwaha shares their predictions on the impact that climate change will have on these extreme weather conditions.

In a study by the Joint Research Centre (JRS) – the European Commission’s in-house science service – new climate impact models are being used to determine future flood risk in Europe under conditions of climate change. These state-of-the-art models, presented by JRS scientist Lorenzo Alfieri, indicate that the change in frequency of extreme river discharge is likely to have a larger impact on the overall flood hazard than changes in their magnitude.

“We predict a 150% increase in future flood risk by 2050”, Alfieri said. This dramatic increase will trigger the so-called “floods of the century” that we currently experience every 100 years, to double in frequency – submerging much of Europe under water within the next few decades. As a result, the extent of damage and number of people affected are expected to increase by 220% by the end of the century.

With more lives predicted to be touched by this climate change-induced flooding, it is of utmost importance to accurately calculate projections of future flood events and to assess the situation that our planet faces. In this study, the JRC applied the most recent climate change projections to assess future flood risk in Europe. Using statistical tools and dedicated analysis, flood simulation was carried out to evaluate changes in the frequency of extreme river discharge peaks.

These projections of future flood events were then combined with data on the exposure and vulnerability of populations, in order to estimate the overall flood risk in Europe under a high-emission climate scenario. Socio-economic scenarios were also investigated. The research addressed both current and future scenarios – with the dates of 2020, 2050 and 2080 used in the socio-economic impact models of large, European river floods.

Satellite picture of Europe. Land terrain and bathymetry (ocean-floor topography). Credit: Koyos (distributed via  Wikimedia Commons)

Satellite picture of Europe. Land terrain and bathymetry (ocean-floor topography). Credit: Koyos (distributed via Wikimedia Commons)

Alfieri estimated that between 500,000 and 640,000 people will be affected by river floods by 2050, increasing to 540,000 – 950,000 by 2080, as compared to 216,000 in today’s climate. A wider range was found for the annual economic impact of flood damage. It is currently estimated at 5.3 billion EUR, set to rise to between 20 and 40 billion EUR in 2050 and to between 30 and 100 billion EUR in 2080. Such predictions are dependent on future economic growth, resulting in the larger range of figures presented at the conference.

Another extreme weather condition that the planet faces is drought – said to increase before the middle of the century. Yusuke Satoh, a researcher from the International institute for Applied Systems Analysis (IIASA) shared new research suggesting that some parts of the world may see unpreceded levels of drought before 2050. These new findings urge swift action to be taken to adapt reservoirs and water management policies in accordance with the depleting water resources.

“Our study shows an increasing urgency for water management systems to adapt for future drought”, Satoh said in a statement at the press conference. “In order for policymakers to plan for adaptation, they need to know when and where this is likely to happen, and have an understanding of the levels of uncertainty in such projections”.

Droughts are predicted to grow more severe and frequent by 2050 for 13 of the 26 countries mapped by the organisation. A new measure was proposed in this study – Timing of Perception Change for Drought (TPCD). This drought will surpass all historical records and countries will reach TPCD at varying times – with western United States feeling the effects as early as 2017, and the Mediterranean by 2027, at current emission rates.

The new study by IIASA combined five different global climate models to examine two different scenarios for future climate change – a 1°C and 3.7°C rise in temperatures by 2100. This technique allowed researchers to address the uncertainty of our planet, since climate change is a manmade environment issue that is difficult to accurately foresee using just one climate model.

From this research, the predicted arrival date of these record-breaking droughts was found to be more uncertain in the Sahara, sub-Saharan Africa and South Australia regions, with certainty very high in southern South America and the Central United States.

Being aware of where the uncertainty lies in the world is important. It allows policymakers and water resource managers to prepare for greater future variations in water availability, since the historical data that the hydrological structures of today are built on, will eventually become void as climate change carves new figures into the history books.

Satoh advised measures such as releasing water from reservoirs during the dry season to relieve the onset of future dryness. “The earlier we take this seriously, the better we will be able to adapt”, he said.

Controlling the amount of seasonal water precipitation and water use, will allow us to manage both the natural and manmade causes of hydrological drought – giving us better control as the effects of climate change begin to set in.

By Nikita Marwaha, EGU Press Assistant and EJR-Quartz Editor