GeoLog

GeoLog

Imaggeo on Mondays: The Gower Peninsula, a coast marked by time

Imaggeo on Mondays: The Gower Peninsula, a coast marked by time

The Gower Peninsula in South Wales, United Kingdom, is a spectacular site to view a sunset. However, to geologists, the shore is also a prime spot to find artifacts from Earth’s ancient and recent past.

“The limestone coastline is dotted with caves that are rich in Quaternary flora and fauna,” said Mike Smith a visiting researcher at Plymouth University (UK) and photographer of this featured image. “Including the famous Red Lady of Paviland, the oldest known ceremonial burial in Western Europe, at 30,000 years before present.”

The peninsula is also known for its “dramatic and visible evidence of climate change over a range of temporal scales,” according to Smith.

A solifluction terrace on the Rhossili Bay in the Gower Peninsula.
Credit: Stephen Codrington. Planet Geography 3rd Edition, 2005 (distributed via Wikimedia Commons).

For example, at the peak of Earth’s most recent glacial period, when the northern ice sheets had made their greatest advances southward, the Gower Peninsula was one of the southern most regions overcome by ice.

Though the last glacial period ended more than 11,00 years ago, you can find evidence of this tundra environment today, if you know what to look for.

For instance, much of the Peninsula’s coastlines are lined by small steeply sloping ridges, separating the coast’s green hillslopes from its sandy beaches. These structures are often referred to as solifluction terraces, and are formed when frozen ground thaws, causing soil, rock and other debris to move downslope.

Additionally, the Gower Peninsula is also host to remnants of our very recent history.

Pictured above are the remains of the shipwrecked Helvetica, a cargo vessel from the late 19th century that had been transporting 500 tons of timber before meeting its untimely end on the banks of Worm’s Head, a small rocky island just a few kilometres long, visible from the peninsula’s shores.

On 1 November, 1887, strong gales just off the coast had taken a hold of the ship, leaving it unable to dock at Swansea Harbour. Instead, the forceful winds blew the vessel into the sandbank of Helwick Sands and then dragged the ship to its final resting place, the shores of Worm’s Head. Helvetica’s captain and crew were forced to abandon ship, and after its cargo was relocated and salvageable parts stripped away, the ship settled deep into the sand.

“The Helvetica is now permanently buried in the beach on a coastline that is bordered by extensive sand dune systems,” remarks Smith.  With each year since, the Atlantic has reclaimed more of the ship, and now just the bare bones of the wreckage remain.

References

Helvetica (Explore Gower)

Hall, Adrian. Cairngorm Landscapes [Edinburgh, Scotland], Solifluction, 2002

Organise a short course at EGU 2019: follow this simple guide!

Organise a short course at EGU 2019: follow this simple guide!

When it comes to supercharging your scientific skills, broadening your base science communication, or picking up tips on how to boost your career, short courses can be one of the highlights of the General Assembly programme.

But, did you know that any EGU member (you!) can propose a short course? You’ve got until 6 September 2018 to complete the application. This quick guide, will give you some pointers for submitting and organising your own short course at the EGU 2019 General Assembly!

Before you even put pen to paper and plan your workshop, remember that the courses should provide a forum to teach your General Assembly peers something of interest. Ideally, short courses should be designed to be open to all conference participants, though they can also be affiliated with one or more of the meeting’s programme groups.

Planning your short course

As the organiser, you are free to choose the content and set-up of the course. But the content should be of interest to (a subset of) the community that the EGU represents! The decision as to whether your course will be included in the final conference programme is made by the programme committee chair, Susanne Buiter, and the short course programme group chairs: the ECS Union representative Stephanie Zihms and Sam Illingworth.

To submit your course, you’ll need:

  • a title and a short description
  • the details of the course organiser

You also have the option to co-organise your course with a scientific division(s) (meaning it’ll appear in the both the Short Course Programme Group and that of your favored division(s)). You might consider doing this if your workshop is aimed at a specific community, as well as being of broad appeal.

Choosing a time-slot

If your short course submission is approved, you can specify preferences for certain time blocks, days or back-to-back scheduling online in the session tagging tool between 12-20 January 2019. Note that assignments depend on availability. No short courses will be scheduled during the poster sessions from 17:30 to 19:00 each day or on the Sunday before the conference officially opens.

The logistics

All short course rooms come complete with a microphone, a data projector, a notebook, wired internet connection, and a VGA switch to use up to three individual notebooks in addition to the permanently installed one of that room. Technical assistance will also be provided in each short course room.

If you require participants to register in advance of the course, it is your responsibility as the organiser to coordinate this. Be sure to include a registration email address or a Doodle link in the description of the short course, so potential participants know how to sign-up.

Food and drink can liven up any meeting! Should you wish to provide catering throughout your workshop (at your own expense), please get in touch with the General Assembly caterer (Motto Catering) by completing their online order form before 31 March 2019. This online form will be made available by the end of the year.

Dos & Don’ts

  • Do make skills/abilities related to science and research the focus of your workshop
  • Do aim to provide training in skills needed by people working in science
  • Do promote your short course
  • Do make your course interactive or include hands-on activities (if possible)
  • Do let participants know (via the description) if they’ll need to bring along materials (e.g. laptop, tablet, specific software) to participate in the course
  • Do allow time for questions

 

  • Don’t invite too many speakers
  • Don’t engage in commercial activities during the course (e.g. sales)
  • Don’t charge admission fees or course fees – these are strictly prohibited

For a full list of guidelines head over to the EGU 2019 website. If you have questions about submitting a short course request please contact the Programme Group Chairs or the EGU Communications Officer, Olivia Trani.

The EGU General Assembly 2019 takes place in Vienna from 7 to 12 April. For more news about the upcoming General Assembly, you can also follow the official hashtag, #EGU19 on our social media channels.

July GeoRoundUp: the best of the Earth sciences from around the web

July GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, as well as unique and quirky research news, this monthly column aims to bring you the best of the Earth and planetary sciences from around the web.

Major stories  

Signs of water 55 million kilometres away

Last week scientists announced that they have found signs of existing water on Mars, offering new hope to the possibility of uncovering life on the Red Planet’s subsurface.  

Radar observations made by the European Space Agency’s Mars Express satellite, suggest that a liquid lake is buried 1.5 kilometres beneath an ice cap situated near the south pole of Mars. Scientists think that this body of water is likely a few metres deep and 20 kilometres across, “nearly three times larger than the island of Manhattan,” reported Scientific American.

A schematic of how scientists used radar to find what they interpret to be liquid water beneath the surface of Mars. (Credit: ESA)

For the last 12 years the Mars Express satellite has been taking measurements of Mars by sending beams of radar pulses into the planet’s immediate interior. As these waves bounce back, the brightness of the reflection gives information on the material lying beneath Mars’ surface.

The researchers involved came across this discovery while analysing three years worth of data collected by the spacecraft.

“The bluer the colors, the brighter the radar reflection from the material it bounced off. The blue triangle outlined in black in the middle is the purported lake,” reported Science News.

Previous observations, made by NASA’s Curiosity rover for example, have found lake beds on the planet’s exterior, signifying that water may have flowed on Mars in the past. However, if this new finding is confirmed, it would be the first discovery of an existing stable body of water, one of the conditions believed to be necessary for life to thrive.

Context map: NASA/Viking; THEMIS background: NASA/JPL-Caltech/Arizona State University; MARSIS data: ESA/NASA/JPL/ASI/Univ. Rome; R. Orosei et al 2018 (distributed via ESA)

“We are not closer to actually detecting life,” said Manish Patel from the Open University to BBC News, “but what this finding does is give us the location of where to look on Mars. It is like a treasure map – except in this case, there will be lots of ‘X’s marking the spots.”

In their study, published in Science last week, the team remarked, “there is no reason to conclude that the presence of subsurface water on Mars is limited to a single location.”

Northern hemisphere feels the heat

In other news, the two words best describing the northern hemisphere this summer could very well “hot” and “dry,” as a series of heat waves have taken hold of several regions across Europe, Asia, North America and northern Africa. Many countries this month, including Japan, Algeria and Canada, have even experienced record-breaking temperatures.

A look at how this year’s heatwave has changed the colour of our vegetation in just one month (Credit: ESA

For some places, above average temperatures and dry conditions have helped fuel devastating wildfires. More than 50 wildfires have swept through Scandinavian forests this summer, many well within the Arctic Circle, causing Sweden to request emergency aid from nearby countries.

Smoke rises from a wildfire in Enskogen. (Credit: Swedish Environmental Protection Agency/Maja Suslin)

A major wildfire also ignited near Athens, Greece this month, resulting in more than 85 death, with dozens still missing. While Greek officials claim that there are “serious indications” that the flames were brought upon by arson, they also note that the region’s climate conditions were extreme.

To many scientists, this onslaught of hot and dry conditions is a taste of what may soon become the norm.  Of course, these conditions (in Europe, for example) are partly due to weather. “The jet stream – the west-to-east winds that play a big role in determining Europe’s weather – has been further north than usual for about two months,” reports the Guardian, leading to sweltering conditions in the UK and much of Europe, while leaving Iceland cool and stormy.  

However, scientists say that heatwaves in the northern hemisphere are very much linked to global warming. “There’s no question human influence on climate is playing a huge role in this heatwave,” said Myles Allen, a climate scientist at the University of Oxford, to the Guardian in the same article.

A recent assessment on the ongoing heat wave in Europe reports that these conditions are more likely to occur due to climate change. “The findings suggest that rising global temperatures have increased the likelihood of such hot temperatures by five times in Denmark, three times in the Netherlands and two times in Ireland,” said Carbon Brief.

What you might have missed

Geologists have given a name to Earth’s most recent chapter: Meghalayan Age. The announcement was made earlier this month when the International Union of Geological Sciences updated the International Chronostratigraphic Chart, which classifies Earth’s geologic time scale. The new update has divided the Holocene Epoch (the current time series which began 11,700 years ago, when the Earth was exiting its last ice age) into three stages: the Greenlandian, the Northgrippian, and then Meghalayan.

The Meghalayan Age represents the time between now and 4,200 years ago, when a mega-drought led to the collapse of many civilisations across the world. The middle phase, Northgrippian (from 8,300 years ago to 4,200 years ago), is marked by an sudden cooling event brought on by massive glacial melt in Canada that affected ocean currents. Finally the oldest phase, Greenlandian, (from 11,700 years ago to 8,300 years ago) is marked by the end of the last ice age.

The recent update has created some unrest in the geosciences community. “There is still an active debate about assigning a new geologic slice of time to reflect specifically the influence of humans on the planet,” reported BBC News. Some scientists say that the new divisions conflict with the current work being done on proposing a new epoch classification, famously called the ‘Anthropocene,’ which would be marked by the beginning on significant human impact on Earth’s geology and ecosystems.

Links we liked

The EGU story

This month we released not one but two press releases from research published in our open access journals. The findings from both studies have important societal implications. Take a look at them below.

New study: oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”

The Baltic Sea is home to some of the world’s largest dead zones, areas of oxygen-starved waters where most marine animals can’t survive. But while parts of this sea have long suffered from low oxygen levels, a new study by a team in Finland and Germany shows that oxygen loss in coastal areas over the past century is unprecedented in the last 1500 years. The research was published in the European Geosciences Union journal Biogeosciences.

New study puts a figure on sea-level rise following Antarctic ice shelves’ collapse

An international team of scientists has shown how much sea level would rise if Larsen C and George VI, two Antarctic ice shelves at risk of collapse, were to break up. While Larsen C has received much attention due to the break-away of a trillion-tonne iceberg from it last summer, its collapse would contribute only a few millimetres to sea-level rise. The break-up of the smaller George VI Ice Shelf would have a much larger impact. The research was published in the European Geosciences Union journal The Cryosphere.

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

Imaggeo on Mondays: Digging out a glacier’s story

Imaggeo on Mondays: Digging out a glacier’s story

This photograph shows landforms on Coraholmen Island in Ekmanfjorden, one of the fjords found in the Norwegian archipelago, Svalbard. These geomorphic features were formed by Sefströmbreen, a tidewater glacier, when it surged in the 1880s.

Although all glaciers flow, some glaciers undergo cyclic changes in their flow. This is called surging, and glaciers that surge are called surging glaciers. During their active phase, surging glaciers speed up and advance. At this time, glaciers collect, transport and deposit large volumes of sediment. This active phase is then followed by a so-called quiescent phase, when glaciers slowdown and retreat. Sediment carried within the ice is then exposed. Often surge-type glaciers produce a characteristic set of landforms, like the red ridges featured here in this photograph.

Only a small proportion of the world’s glaciers surge. Svalbard is home to many of these surging glaciers, and the length of the surge cycle varies by region. A quiescent phase of surging glaciers in Svalbard can last between 10 and 100 years. An active phase is commonly between 1 and 10 years. Surging glaciers are enigmatic; we still do not fully understand all the processes that cause these glaciers to switch between active and quiescent phases.

When Sefströmbreen surged, it advanced over the fjord and overrode Coraholmen Island. The glacier deposited up to 0.2 km3 of sediment on the western side of the island. As a result, the island doubled in size. The red ridges in the foreground of the photograph were formed when sediment under the glacier was squeezed up into crevasses, large cracks in the ice. Once the ice melted, these crevasse-squeezed ridges were exposed. They contrast in colour with grey Kolosseum Mountain in the background.

Glaciers are useful indicators of past climate and they are used for climate reconstructions. However, surging glaciers are not suitable for such reconstructions. This is because glacier surging is not directly related to climate. When a surging glacier advances during its active phase, it does not mean that the climate is colder. This also holds true for the past. If a surging glacier was bigger at some point in the past, it is not because the climate at the time was colder. If we didn’t know that the glacier surged, we would make a wrong inference about climate. Therefore it is important to know which glaciers are surging-type glaciers.

To document surging behaviour of glaciers, we can use historical sources, glaciological observations and satellite images. If no such records exist or if we are interested in time period that precedes satellite observations, we rely on landforms to tell us the story. We can study these landforms, their appearance, shape, structure, and what they’re made of to learn about past behaviour of glaciers, their dynamics, and processes that go on underneath a glacier where it meets its bed.

The photograph was taken during a field cruise as part of the University Centre in Svalbard’s Arctic Glaciers and Landscapes course.

By Monika Mendelova, University of Edinburgh (UK)

References

Boulton, G.S. et al. Till and moraine emplacement in a deforming bed surge — an example from a marine environment. QSR 15, 961-987. 1996

Evans, D.J.A., & Rea, B.R. Geomorphology and sedimentology of surging glaciers: a land-systems approach. Ann. Glaciol. 27, 75 – 82. 1999

Dowdeswell, J.A. et al. Mass balance change as a control on the frequency and occurrence of glacier surges in Svalbard, Norwegian High Arctic. Geophys. Res. Lett. 22, 2909-2912. 1995

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/.