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This guest post was contributed by a scientist, student or a professional in the Earth, planetary or space sciences. The EGU blogs welcome guest contributions, so if you've got a great idea for a post or fancy trying your hand at science communication, please contact the blog editor or the EGU Communications Officer Laura Roberts Artal to pitch your idea.

Geosciences Column: A new rock outcrop map and area estimation for the entire Antarctic continent

Geosciences Column: A new rock outcrop map and area estimation for the entire Antarctic continent

Antarctica has been known as “the frozen continent” for almost as long as we have known of its existence. It may be the only place on Earth where, instead of information on the extent of glaciers or ice caps, there exists a dataset of all non-icy areas compiled from satellite imagery.

However, this repository is far from perfect: while satellite resolution and coverage have been steadily improving, Antarctica is challenging ground for remote sensing. Ice and cloud cover can be difficult to tell apart, and the low position of the sun in the sky means that long shadows can make snow, ice and rock very difficult to distinguish. As a result, the estimates of the ice-free proportion of the Antarctic continent have been vague, ranging from “less than 1%” to 0.4%.

In a new paper published in the journal The Cryosphere, scientists from British Antarctic Survey and the University of Birmingham show that the continent is even icier than previously thought. Using imagery from NASA’s Landsat 8 satellite, they find that just 0.18% of the continent are ice-free – less than half of previous estimates. This equates to an area roughly the size of Wales on a continent half again as big as Canada.

Lead author Alex Burton-Johnson and his colleagues have developed a new method of accurately distinguishing between ice, rock, clouds and liquid water on Antarctic satellite imagery. Because of the challenging nature of classifying Antarctic satellite imagery, the researchers used only the highest-quality images: they were mostly taken in midsummer, when the sun describes the highest arc in the sky and shadows are smallest, and on days with low cloud cover.

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(Left) The blue squares represent the coverage of the 249 satellite images the researchers used, showing that most rocky areas in Antarctica are clustered along the coastline. The images overlap in many places, allowing for more accurate classification where some clouds occur in pictures. (Right) The new dataset for rock outcrops covers all areas marked in red. The NASA Landsat 8 satellite does not cover areas south of 82°40′ South. Islands such as South Georgia and the South Orkney Islands are too consistently cloudy during the summer period, so the new method cannot be applied here. From : Burton-Johnson et al. (2016).

The huge thickness of the Antarctic ice sheet – more than 4,000m in some places – made the scientists’ job easier: they could exclude large parts of the continent where not even the tallest peaks come close to the ice surface. A total of 249 suitably high-quality images covered those parts of the Antarctic continent that have rock outcrops.

A few locations, however, are too extreme for the new image classification method. Some of the South Orkney Islands and the subantarctic island of South Georgia are covered in heavy cloud for so much of the time even in summer that the researchers could not apply their new method. Here, they had to rely on the older dataset. They also had to exclude parts of the rugged but remote Transantarctic Mountains from the study as the Landsat 8 satellite only covers areas north of 82°40’S.

The code for the new classification methodology is available on GitHub, so that enthusiastic remote sensers can try their hand at further improving it or simply admire the frozen beauty of Antarctica from above.

By Jonathan Fuhrmann

References

Burton-Johnson, A., Black, M., Fretwell, P. T., and Kaluza-Gilbert, J.: An automated methodology for differentiating rock from snow, clouds and sea in Antarctica from Landsat 8 imagery: a new rock outcrop map and area estimation for the entire Antarctic continent, The Cryosphere, 10, 1665-1677, doi:10.5194/tc-10-1665-2016, 2016.

Imaggeo on Mondays: Living flows

Imaggeo on Mondays: Living flows

There are handful true wildernesses left on the planet. Only a few, far flung corners, of the globe remain truly remote and unspoilt. To explore and experience untouched landscapes you might find yourself making the journey to the dunes in Sossuvlei in Namibia, or to the salty plain of the Salar Uyuni in Bolivia. But it’s not necessary to travel so far to discover an area where humans have, so far, left little mark. One of the last wilds is right here in Europe, in the northern territories of Sweden. Today’s spectacular photograph of the Laitaure delta is brought to you by Marc Girons Lopez, one of the winners of the 2016 edition of the EGU’s Photo Contest!

The photograph shows a part of the Laitaure delta, at the entrance of Sarek National Park (Northern Sweden). Sarek is one of the oldest national parks in Europe and it is often considered to be one of the last wild areas in Europe. The Sami people, however, have traditionally used these lands.

This delta is formed by the Rapa River when it flows into Lake Laitaure. The Rapa River springs from the Sarektjåkkå glacier and is fed by over thirty glaciers. The specific flow of the Rapa River — the ratio between its flow and the area of its catchment — is the highest in Sweden. The magnitude of the flow has strong seasonal fluctuations which are reflected in the sediment transport, which can be as high as 10,000 tons per day during the summer. This heavy sediment load gives the river its characteristics greyish colour. The different colours in the backwater zones may be produced by dissolved organic matter from decomposing vegetation.

The delta in this area is flanked by  patches of montane forests along the river banks in an area otherwise covered by marshes. Regarding the fauna, according to Wikipedia the Eurasian teal, the Eurasian wigeon, the greater scaup, the red-breasted merganser, the sedge warbler and the common reed bunting are common in the Laitaure delta.

By Marc Girons Lopez, researcher at the Centre for Natural Disaster Science, Uppsala University

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/.

 

GeoSciences Column: Improving together – science writing and football

GeoSciences Column: Improving together – science writing and football

Writing is something that those pursuing a career in academia are expected to be good at. It is a requirement of the job, yet it is a skill few get any formal training in and simply rely on the old saying that practice makes perfect. But what if there is another way? Mathew Stiller-Reeve is a co-founder of ClimateSnack, a writing group organization, which aims to tackle the problem. In today’s post Mathew considers how the workings of a football team might reflect the successes of the writing groups that started in the ClimateSnack project.

The premise behind the ClimateSnack project is simple: We need to improve our writing in science. But many young researchers do not have access to good training initiatives, especially not continuous ones. So, maybe we should just mobilize ourselves; we can mobilize ourselves by starting writing groups and working together to improve. In ClimateSnack, early career scientists (ECS) start writing groups at their home institute. Participants write short popular science articles (usually 400-500 words), read them aloud, get feedback, and publish online. Several ClimateSnack writing groups sprouted up all over the world, however, only a few truly blossomed. What made some groups work and some not? We analyzed the answer to this question in our new paper. The style of a peer-review paper didn’t allow us to make fancy, lengthy analogies. But on GeoLog, I feel safe using football as an analogy to explain the workings of a writing group, and maybe infuse some of my own personal opinions too.

Football is a team sport, but you can play football completely alone and still become an expert. You can see this when you watch football freestylers (like Indi Cowie in the video) do their incredible tricks. Most of these tricksters likely play football with a whole team, but they don’t have to. The same applies to science writing and communication. You can become an expert in these skills by yourself, and some people prefer this. But for ECS’s who like to work together, ClimateSnack would give them the opportunity to improve as part of a team: a writing group.

But what was needed for the teams to work successfully? And what did we learn from the teams that disbanded after a few training sessions?

Successful football teams have good leadership, and in particular good captains. Good captains bring out the best in their players, encourage them when things get hard and manage conflict. These elements were reflected in the ClimateSnack writing groups. The strong leaders guided the groups and encouraged participants to contribute in sensitive ways. However, strong leaders don’t stick around forever. Just as other football clubs often buy captains, writing group leaders also moved on; they finished PhDs and got jobs far, far away. New captains needed to be found, but this was always a challenge.

Can the workings of a football team reflect the successes of the writing groups that started in the ClimateSnack project? Credit: Syaza , distributed via gify.

Can the workings of a football team reflect the successes of the writing groups that started in the ClimateSnack project? Credit: Syaza , distributed via gify.

I am absolutely not saying that the leaders of the disbanded other groups were poor captains! Even a potentially good captain cannot lead a team if he/she doesn’t know the rules of the game. If the rules are not clear then the whole team cannot play properly together. They need to know where the goal is; they need to understand the game’s objectives. And this is where the ClimateSnack management team (where I am most to blame!) was shortsighted. We failed to properly communicate the objectives and aims of a ClimateSnack writing group and the writing process we suggested.

Even if a football team knows the rules and has a good captain, they won’t get far if morale is low, or if the players haven’t got time to train or turn up for matches. We noticed that a lot of the motivation within writing groups was linked to socializing. Just as some amateur football teams might go to the pub after training, one successful writing group planned their meetings just before the Department coffee break so everyone could socialize after the hard work was done.

What other elements need to be in place for a football team to work?

The right number of players is an absolute necessity. Most people have seen how a football team struggles after a couple of players have been sent off. You may have also heard about players going to other clubs if they don’t get to play enough matches. The ClimateSnack group meetings also faced challenges with the number of participants. One group had so many participants to start with that it became difficult to manage. It is difficult for everyone to get something out of a peer feedback discussion if too many are involved.  In this instance, participants lost interest and numbers decreased steadily and finally to a level where too few attended and the group disbanded. In our Bergen group, we always find that the best discussions happen with 4-6 people at the meetings. If we get far more than this in the future, then we will likely split into smaller discussion groups which work more effectively.

Effective writing groups demand some kind of time commitment from the participants. Good writing requires practice, just like football. Football players often train several times a week. With ClimateSnack, we did not have the luxury of asking the members for this level of commitment. Students are already under pressure from a variety of different sources. They need to complete mandatory courses, collect data, attend conferences, and work as teaching assistants. People who play football have a passion for the game and make time for it. Unfortunately, few young researchers have a passion for writing (cards on the table: I was exactly the same. It took a lot of time before I started enjoying writing). Therefore, something voluntary like a writing group will often fall by the wayside when to-do lists are being compiled.

A football team celebrates together after scoring a goal!

A football team celebrates together after scoring a goal! ( Lewes Ladies 2 BHA 1 4 May 2014. 645 , credit: James Boyes distributed via a href=” https://www.flickr.com/”> flickr).

Some ClimateSnack teams started scoring goals! ClimateSnack participants have published over 100 articles online, some of which articles have appeared in newspapers here in Norway. Many participants feel that their writing has improved. Some participants have even started receiving better peer reviews for their scientific publications. Other participants have also used their new network to organize science communication workshops. Even if many writing groups didn’t find a footing, for some people the concept worked really well. And many people have made good friends!

Just like with many football teams, they are more likely to score more goals if they have generous sponsors. Football clubs need to buy kits, pay for pitch maintenance and travel to play other teams. A writing group project like ClimateSnack ideally needs some funding to let new ideas flourish and allow different groups to interact and learn from each other. The ClimateSnack founders had big ambitions to create an international online community where ECS would interact and peer-review each other’s articles across borders. We secured some funding to update the website, but never to implement the kind of things needed to properly promote an international community.

Despite the challanges we encountered, we have seen that writing groups can be a really effective way to learn writing skills together (like ours in Bergen in the photo). Maybe they are so effective that universities should consider implementing them in curricula for all students at all levels. With this in mind, I’ll indulge with a final football-related analogy. When I was a child, we had to play football at school. I didn’t like it! However, now I appreciate that I got fit and healthier, and I learned skills that I could apply to other sports in the process. You see the link to learning basic writing skills?

Indeed, if you think about it, I could have applied the football team analogy to any aspect of research education: We can learn anything alone, but it can be more enjoyable and rewarding if we learn together. However, I think the analogy works well with communication. After all, this is the part of the research process where we really have to put ourselves out there, we have to receive feedback, debate our results, and defend our conclusions, often in open forums. These are all elements at the forefront of writing group dynamics.

Read more about the highs and lows of our ClimateSnack project in our paper in the recent HESS/NHESS special issue on Effective Science Communication and Education in Hydrology and Natural Hazards.

By Mathew Stiller-Reeve, co-founder of ClimateSnack and researcher at Bjerknes Centre for Climate Research, Bergen, Norway

Reference

Stiller-Reeve, M. A., Heuzé, C., Ball, W. T., White, R. H., Messori, G., van der Wiel, K., Medhaug, I., Eckes, A. H., O’Callaghan, A., Newland, M. J., Williams, S. R., Kasoar, M., Wittmeier, H. E., and Kumer, V.: Improving together: better science writing through peer learning, Hydrol. Earth Syst. Sci., 20, 2965-2973, doi:10.5194/hess-20-2965-2016, 2016.

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/.

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