Category Archives: EGU 2017

EGU 2017: New atlas shows polar seabeds

by Liz Kalaugher

Frost polygons: This polygonal or geometric patterns on the shallow seafloor (10-17 m water depth) here shown on a side-scan sonar image, were formed when the area was emergent (land) during the last glacial and was permanently frozen but not covered by glaciers.

Frost polygons: This polygonal or geometric patterns on the shallow seafloor (10-17 m water depth) here shown on a side-scan sonar image, were formed when the area was emergent (land) during the last glacial.

Wednesday saw a team of geophysicists at the EGU meeting present their new Atlas of Submarine Glacial Landforms. Four years in preparation, the atlas is the work of more than 250 marine geologists and glaciologist and is the most comprehensive and high-resolution atlas to date of the seafloor of both polar regions. The last such atlas was created 20 years ago.

Kelly Hogan, one of the Atlas editors, detailed at a press conference how the atlas reveals how ice has shaped the sea floor. Scientists will use the atlas to interpret the history of Earth’s large ice sheets and examine how environmental change reshaped continents.

Iceberg ploughmark showing rotation amongst a field of pockmarks from the central Barents Sea. Red 240 m water depth, purple 252 m.

Iceberg ploughmark showing rotation amongst a field of pockmarks from the central Barents Sea. Red 240 m water depth, purple 252 m.

The atlas assembles images of the sea floor that together cover an area the size of Great Britain. Modern acoustic mapping from onboard ship can image glacial landforms that are as much as five times smaller than earlier methods. Multibeam bathymetry, for example, creates a fan of sound and measures the return time of each ping to measure water depth across the fan. The researchers also used seismic reflection to look at sediment and remotely operated vehicles to take pictures from the seafloor.

These techniques revealed permafrost patterns on the floor of the Laptev Sea that became submerged when sea-level rose. The patterns are well-preserved because of the absence of weathering and human activities like road-building. In the Barents Sea the atlas shows ploughmarks on the seabed caused by the keel of an iceberg, in what’s one of Hogan’s favourite pictures.

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Are scientists at EGU telling stories?

by Liz Kalaugher

“It’s sitting by the campfire telling stories 15,000 years later.” Those were the words of Rolf Hut of Delft University of Technology in The Netherlands, explaining how playing Dungeons and Dragons as a teenager taught him how to create narrative structures for his research that makes it appeal to the media. He was speaking as part of a PICO interactive poster session at the European Geosciences Union (EGU) general assembly.

Hut’s media exploits include wearing a suit at this year’s EGU made of a recycled academic poster, simulating an escape from Alcatraz, and donning a pair of “smart” angling waders rigged up with a thermocouple in the EGU poster halls in 2015.

The classic pyramid structure for news stories, which starts with the essential information before following up with background, is the opposite of a research paper, Hut said. Scientific papers provide the background first “to weed out readers who are not interested” and only details results later. But “your science is not news”, Hut told delegates – today it’s more likely to appear in the weekend papers or on TV. And that requires a narrative structure, more like that of a movie, with an inciting incident, action that reaches a crisis, a climax and a denouement.

That’s where Dungeons and Dragons comes in – Hut reckons he had six years’ practice telling stories in basements. To prove his point, at the end of the session Hut, together with Sam Illingworth of Manchester Metropolitan University, UK, who’s authored an IOP ebook on science communication that at the time of writing is free to download, enticed researchers at the PICO session to play a story-telling game called No Sleep Tonight, where they had to create narratives on the fly using word-prompts.

Earlier in the session, delegates heard tips and tricks from other researchers, some of whom had jumped in at the deep end of communicating their science.

Hubert Savenije of Delft University of Technology in the Netherlands, in a talk about the tightrope between drawing media attention and exaggeration, described what happened after his inaugural professorship lecture at IHE Delft in 1995. During the lecture, Savenije discussed the flooding of the Maas river in The Netherlands in 1993 and criticized the government’s water management. Even though he’d sent out a press release, Savenije’s comments did not attract media attention at the time.

But when more flooding took place, the release caught the eye of a reporter. An interview with Savenije appeared on the front page of a Dutch newspaper and the following week was “as if all hell broke loose”. The scientist came under pressure from the Dutch ministry to rectify his comments. “I had overdone it,” he said. But media attention can have advantages too, he explained, despite causing jealousy amongst colleagues. Getting your name known can give you the opportunity to write longer follow-up articles that detail the full picture. Savenije’s tips for others? Ask to see the article before publication to avoid misinterpretation, don’t overdo it, and be aware of topical events that may give your work additional exposure.

A topical event – the German drought in the summer of 2015 – brought exposure to Kerstin Stahl of the University of Freiburg, Germany. Stahl was approached by the media, she said, as she was listed on her institution’s experts service and had had two new projects on drought risk funded that year. Stahl found that the media questions were often specific, referring to times, places and dates. Her research, in contrast, tended to produce generalised messages and weigh up different factors.

From drought to flood: Louise Slater a flood risk researcher from Loughborough University, UK, recommended ensuring that you’re easily findable when journalists google key words, by maintaining a personal website and using Twitter. Slater also suggested asking for the journalists’ angle and their questions in advance, being able to convey your main message in 15 seconds, and preparing three key points and having a personal example for each point. Slater, for instance, talks about how the weeds in her local river are boosting the probability that it will flood.

When Jan Seibert of the University of Zurich, Switzerland, and Uppsala University in Sweden found that his students had hit the news for accidentally colouring a river too green, he was able to turn the coverage into an explanation of the research. Siebert is now looking to boost participation in his CrowdWater citizen science project and is building its exposure in social media as well as creating a MOOC on water in Switzerland. His team found that a personal approach – asking for help with their PhDs – worked better than asking people to help save the planet.

Tom Gleeson of the University of Victoria, Canada, who blogs for the EGU and AGU, recommended scientists have their own “research brand” and an Excel spreadsheet listing their communication goals and priorities. Gleeson aims to use real, natural language, without acronyms, and practices science communication on people he sits next to on the ferry near where he lives. He thinks scientists should be humble, honest and engaging, and suggests that they have one to three key points, keep a media network on another Excel spreadsheet and use their institution’s media relations team (although experience has shown him that not every paper warrants a press release),. Despite being a “smartphone hold-out” Gleeson recommends finding a community on social media – his Twitter handle is @water_undergrnd.

Anna Solcerova of the Delft University of Technology, who hit the media on Monday after taking part in an EGU press conference, has language tips too. Solcerova picked a short and snappy title for her abstract – “How cool is uchimizu?” – rather than describing it as a measurement study of the cooling effect of direct evaporation of water on urban pavement. She believes this may have been instrumental in EGU press officer Bárbara Ferreira selecting this paper for extra attention. Solcerova also recommended talking in short, quotable sentences and taking lots of photos of your research.

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EGU 2017: Much groundwater is ‘surprisingly old’ but may be contaminated

Groundwater stores 100 times more water than all the world’s lakes put together and supplies around 40% of the water for irrigated agriculture. And most of that groundwater is “surprisingly old”, according to James Kirchner of ETH Zurich and Swiss Federal Research Institute WSL in Switzerland, speaking at a press conference at the European Geosciences Union general assembly in Vienna.

The bulk – 42-85% – of this groundwater in aquifers in the upper 1 km of the Earth’s crust is “fossil” groundwater that’s more than 12,000 years old, Kirchner, Scott Jasechko and colleagues have estimated, so it was around “when mammoths roamed”. There’s roughly twice as much of this ancient water by volume as modern groundwater that collected within the last 60 years.

What’s more, previously scientists had assumed that this ancient water was isolated from modern contamination such as pesticides. But Kirchner and the team found that around half of the wells dominated by fossil groundwater contained modern water too. So it’s not safe to assume that the older groundwater is free from manmade contaminants like fertilizers or chlorinated hydrocarbons.

“It’s like going to a giant old folks’ home and finding little kids running round,” said Kirchner. “It’s great unless the kids have ‘flu.”

Kirchner stressed that it’s not that half of the world’s groundwater is now known to be contaminated but that we cannot exclude the possibility that it may include contaminants.

To age the groundwater, the researchers assembled existing data on the age of groundwater from thousands of wells based on its contents of isotopes of carbon and tritium. A hydrogen isotope, tritium was released into the atmosphere in large quantities by thermonuclear testing that began in the early 1950s so it acts as a tracer for more recently recharged groundwater. Carbon-14 has a half life of nearly 6,000 years so if water is depleted in C-14 it hasn’t “seen the atmosphere” for at least 12,000 years.

The fossil and modern groundwater may mix either in the well or in the aquifer beneath; it’s not yet clear which. Wells deeper than about 250 metres mainly pump fossil groundwater, Kirchner explained. Many of these fossil sources may be non-renewable on human timescales. The High Plains aquifer in the US, for example, contains rain that mainly fell in the Pleistocene but its water level has dropped more than 100 metres in the last few decades and it would take 6,000 years to replenish.

The paper was published in Nature Geoscience yesterday.

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Arctic sea ice: observations and models suggest open water in September by mid-2040s

by Liz Kalaugher

In 2016 Arctic sea ice extent set a new record low, and every single month that year had an Arctic sea ice extent more than two standard deviations – corresponding to over 1 million square km of ice – below the long-term mean. That’s according to Julienne Stroeve of the University of Colorado, US, and UCL, UK, speaking at the European Geosciences Union meeting in Vienna.

Stroeve, who came back from Arctic field work on Friday, reported that both the first year sea ice and the multiyear ice that she measured were thinner than usual. As she left, strong winds were starting to create open water. “I think it’s going to be an exciting summer,” she said.

As the ice thins, it becomes more vulnerable to atmospheric conditions. Since 2007 Arctic sea ice extent has shown larger variability, making it harder to predict the ice cover in September. But at some point the ice may become so thin that atmospheric circulation doesn’t matter anymore, Stroeve explained.

Over the long term, the ice has retreated by 14% per decade, with the ten lowest summer sea ice extents all occurring within the last ten years. And the last seven months, including January through March of 2017, have been the longest consecutive run of unusually low sea ice extents.

Stroeve’s calculations, based on field observations, indicate that each metric ton of carbon dioxide entering the atmosphere melts three square metres of ice. That makes the ice more sensitive to greenhouse gases than models suggest. And it reveals that emission of a further 1000 Gigatonnes of carbon dioxide (which would be likely to create a 2 degree temperature rise) would create an ice-free Arctic in summer. At our current emission rates of roughly 30-40 Gigatonnes per year, that would mean an ice-free Arctic in September by 2045.

This date agrees with a climate model-based projection by James Screen of the University of Exeter, UK, and his colleague Daniel Williamson, who estimated that the first ice free September will be in around 2046, for a temperature rise of 2.1 degrees. This date would come forward to 2040 if emissions were higher or be delayed until 2050 if they were lower. And natural variability makes it accurate only to within 20 years. Screen’s earliest possible ice-free scenario was in the mid-2020s, for a temperature rise of 1.7 degrees.

Screen has calculated that if we keep to the UN “stretch target” of 1.5 degrees of warming, the probability of the Arctic being ice-free in summer is less than 1%. But for 2 degrees of warming, the chances are 39%, or “toss a coin” as he put it, and for 3 degrees, the probability is 73%, “likely” in IPCC terms.

This is in line with field observations of ice extent being more sensitive to climate change than models project – Stroeve’s observation-based calculations projected an ice-free Arctic in summer for 2 degrees of temperature rise, whilst Screen’s modelling indicates a 39% chance.

So what’s our temperature rise trajectory? Business-as-usual emissions would bring a global average temperature rise of 3-5 degrees by the end of the century, Screen detailed, whilst current emissions pledges to the UN would see temperature rises of 2.6-3.1 degrees. We’ve already raised temperatures by 0.9-1 degrees so we have around half a degree to go before hitting the UN stretch target.

“If we really want to save Arctic sea ice, we need to push for 1.5 degrees, not 2,” said Screen.

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Ancient Japanese technique becomes cool again

by Liz Kalaugher

The 17th century saw Japanese citizens sprinkle water onto the ground and walls around their temples, gardens and houses. Not only did this suppress dust formation but it also cooled temperatures by evaporation. Now Tokyo is promoting uchimizu once more and a team from the Netherlands has investigated exactly how much this uchimizu technique could benefit today’s cities.

As Anna Solcerova of the Delft University of Technology in The Netherlands detailed at the European Geosciences Union (EGU) meeting in Vienna, adding just 1 or 2 mm of water to a paved area can reduce air temperatures near the ground by as much as 8-10 degrees and at human height by up to 2 degrees.

To come up with these figures, Solcerova and colleagues Tim van Emmerik and Koen Hilgersom fitted a 1 x 1 x 1 m cube with fibreoptic temperature sensors, providing 3D Distributed Temperature Sensing (DTS) measurements at 35 heights.

Adding water always cools the ground, the team found, but the effect is greater when the heat is less intense, or in shade. Solcerova stressed that it’s important to use rainwater rather than tap water for uchimizu and that the technique boosts humidity – whilst this would not be an issue in the Netherlands, it may be elsewhere.

The uchimizu technique died out with the advent of aircon units that can cool a room to any temperature desired, although on the downside, the units spew additional heat into the city outside. Perhaps we’ll see more of uchimizu in the future.

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