It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Study reveals lower school attendance on Fridays in England
Economists from the University of Bath believe that end-of week-absenteeism could be linked to beating bank holiday traffic.
University of Bath
Economists from the University of Bath have found a significantly lower school attendance rates on Fridays across England, with a 20% higher absence rate compared to other weekdays.
The “Friday” effect highlights children are much less likely to attend primary and secondary school at the end of the week.
Published in the British Educational Research Journal, the study used daily level attendance data at local authority level collected by the Department for Education (DfE) from the beginning of the academic year 2022/2023.
Key Findings:
Absence rates are 17% higher on Fridays compared to the rest of the week in primary schools.
Absence rates are 22% higher on Fridays compared to the rest of the week in secondary schools.
Overall, absence rates are 20% higher on Fridays, compared to the rest of the week, across all schools in England. To put this into context, eliminating this 'Friday effect' (i.e. setting the Friday absence rate to that of the Monday to Thursday) could mean around 130,000 more students attending school each Friday.
The “Friday effect” is more pronounced in areas with higher levels of deprivation.
Why is there a Friday effect?
Dr Jonathan James, from the Department of Economics, explains the possible reasons behind this trend:
We found no evidence to suggest that parents working from home are driving the higher absence rates on Fridays. We also rule out strikes. However, our research indicates that Friday absences are more common in weeks leading up to bank holidays or half-term breaks, suggesting that families might be extending their holidays or trying to avoid holiday traffic Addressing these patterns could reduce the effect by one-third to a half.
This is the first study to highlight a "Friday effect" in school attendance, but Dr. James believes it's not a new issue. While examining National School Admission Registers & Log Books from 1870 to 1914, Dr. James found a note from Merrow Church of England School in Surrey, dated 1899, which stated: "Of late, several children have absented themselves on Friday."
Recent data supports the idea that “The Friday effect” has worsened since the Covid-19 pandemic. A study by Gunter and Makinson (2023) looked at data from 6,000 schools and found that Friday absences in secondary schools used to be lower compared to the rest of the week. In 2013/14 school year, Friday absences were 0.7 % lower than the weekly average. By the 2018/19 school year, this had flipped, with Friday absences being 0.9% higher. This gap widened even further by 2022/23, with Friday absences being 1.4% higher than the weekly average. Dr James said:
There might be a cultural aspect to this—perhaps there's less stigma about taking Fridays off now. With the cost of living crisis, people may be more understanding of the financial pressures families face, such as the high cost of holidays. However, we do not yet have concrete evidence to fully support this hypothesis.”
Why does it matter?
The researchers think addressing the “Friday effect” could improve students' academic performance and even their future earnings. Co-author Dr Joanna Clifton-Sprigg said:
Tackling these patterns of weekly absences can help raise attainment levels and reduce educational inequalities.”
The University of Bath research team hopes these findings will inform policies aimed at reducing school absences. Dr Clifton-Sprigg added:
Simple measures like sending newsletters, emails, or text messages to remind parents of the negative impact of absences on academic performance could be effective. Additionally, schools might consider scheduling engaging activities on Fridays, such as award ceremonies, to boost attendance."
A group of MPs have issued a call for the UK government to trial moving staff at the Department for Environment, Food and Rural Affairs (DEFRA) onto a four day working week.
The MPs have all signed an Early Day Motion in parliament which argues that “a four-day week with no loss of pay could lead to increased productivity, while also bringing benefits to workers, employers, and wider society”.
The motion highlights the four day week trial in South Cambridgeshire District Council and claims that this “showed huge benefits, including cost savings, better staff retention, lower sickness rates and improvements in service delivery”.
The Early Day Motion comes off the back of a campaign from the PCS union to secure a trial four day week in DEFRA. Earlier this year, PCS said that DEFRA management had “agreed to work collaboratively to explore the idea of a four-day week”. However, the department is yet to to commit to implementing a pilot.
At the time of writing, 11 MPs have signed the Early Day Motion. The following MPs have added their names:
John McDonnell – Independent Clive Lewis – Labour Ian Lavery – Labour Andy McDonald – Labour Liz Saville Roberts – Plaid Cymru Kim Johnson – Labour Ann Davies – Plaid Cymru Ben Lake – Plaid Cymru Llinos Medi – Plaid Cymru Neil Duncan-Jordan – Labour Jon Trickett – Labour
In 2023, the largest four day week trial in the UK concluded, with 56 out of the 61 organisations involved deciding to continue to operate on a four day week. The trial saw a significant decrease in the rates of stress and illness among workers who took part.
Chris Jarvis is head of strategy of development at Left Foot Forward
1933
Boost in tackling global pesticide suicides
University of Edinburgh
The drive to prevent suicides from pesticide poisoning in low and middle-income countries will continue at the University of Edinburgh thanks to new investment.
The Centre for Pesticide Suicide Prevention (CPSP) is estimated to have saved between 15,000 and 30,000 lives over the past three years by improving regulation of highly toxic pesticides in countries across Asia.
A donation of £6.5million from Open Philanthropy, who have supported the centre since its formation in 2017, will enable researchers to expand into new countries as they bid to significantly reduce suicides from pesticide poisoning.
By removing highly hazardous pesticides from agricultural practice, experts estimate that global pesticide suicide rates will fall rapidly from more than 100,000 deaths a year to less than 20,000.
Global issue
Pesticide poisoning is one of the most common methods of suicide worldwide. It is believed that more than 14 million people have died from pesticide self-poisoning since the 1960s.
It is a particular problem in low and middle-income countries where more than 77 per cent of global suicides occur. Vulnerable people living in rural farming communities have easy access to highly toxic pesticides, most of which are already banned in high-income countries.
These dangerous products are often sold locally without controls and stored in homes and gardens. Rural communities do not have the capacity to use or store these pesticides safely. Community interventions, such as locked storage containers, are ineffective.
Effective action
Since 2017 researchers from CPSP have worked with regulators and policymakers in low and middle-income countries to identify pesticides responsible for deaths and end their use through regulatory action.
In 2019, as a direct result of CPSP research and engagement, Nepal introduced a national ban on five highly hazardous pesticides with the specific aim of reducing suicides.
The southern Indian state of Tamil Nadu announced a temporary ban on six pesticides in early 2023 following consultation between CPSP researchers and the departments of health and agriculture.
CPSP has also worked with regional groups of pesticide regulators in Africa, supporting the development of regional action plans on highly hazardous pesticides.
Researchers from the centre also work closely with United Nations organisations, including the World Health Organisation and the Food and Agriculture Organisation.
The centre hopes to further develop its work in Africa and the Caribbean, building on its initial success in Asia.
We are delighted that our work continues to be recognised for its impact. Suicides are preventable and we have a clear, effective solution that is saving lives. While we are proud of what we have achieved over the last seven years, there is still much more to do. Sadly, these lethal and totally unnecessary pesticides are still being manufactured and sold to the world’s most vulnerable people. This generous donation will allow us to continue our work to stop this violation of human rights.
Professor Michael Eddleston, Director of the Centre for Pesticide Suicide Prevention at the University of Edinburgh
New discovery about ice layer formation in ice sheets can improve sea level rise predictions
University of Texas at Austin
image:
Meltwater streaming across the top of the Greenland ice sheet. A study led by researchers at The University of Texas at Austin examines the flow and freezing of meltwater within old snow on the ice sheet, which can help improve estimate of sea level rise.
A newly discovered mechanism for the flow and freezing of ice sheet meltwater could improve estimates of sea level rise around the globe.
Researchers from The University of Texas at Austin in collaboration with NASA’s Jet Propulsion Laboratory (JPL) and the Geological Survey of Denmark and Greenland (GEUS) have found a new mechanism that explains the process of how impermeable horizontal ice layers are formed below the surface, a process critical for determining the contribution of ice sheet meltwater to sea level rise.
The work by Mohammad Afzal Shadab a graduate student at UT’s Oden Institute for Computational Engineering and Sciences was published in Geophysical Research Letters. Shadab was supervised by study co-authors Marc Hesse and Cyril Grima at UT’s Jackson School of Geosciences.
The world’s two largest freshwater reservoirs, the Greenland and Antarctica ice sheets, are covered in old snow, known as firn, that’s not yet compacted into solid ice. Because the firn is porous, melted snow can drain down into the firn and freeze again rather than running into the sea. This process is thought to decrease meltwater runoff by about half.
However, it’s also possible to form impermeable ice layers that can serve as barriers for meltwater – and divert meltwater to the sea, said Shadab.
“So, there are cases where these ice layers in firn accelerate the rate of meltwater running into the oceans,” he said.
The potential for glacial meltwater to freeze in firns or flow off existing ice barriers makes understanding freezing dynamics within the firn layer an important part of estimating sea level rise, according to the researchers. Previous work on firn in mountains, which also contains ice layers, found that these ice layers are created when rainwater accumulates, or ponds, on older layers within the firn and then refreezes. But according to Hesse, it didn’t seem to work that way for ice sheets.
“When we looked at the data from Greenland, the actual amount of melt that’s being produced, even in an extreme melt event, is not enough to produce ponds,” said Hesse. “And that’s really where this study has come up with a new mechanism for ice layer formation.”
This new research presents ice layer formation as a competition between two processes: warmer meltwater flowing down through the porous firn (advection) and the cold ice freezing the water in place by heat conduction. The depth where heat conduction begins to dominate over heat advection determines the location where a new ice layer forms.
“Now that we know the physics of the formation of those ice layers, we will be able to better predict the meltwater retention capability of firn,” said study co-author Surendra Adhikari, a geophysicist at JPL.
Anja Rutishauser, a former UT postdoctoral researcher who is now a now at GEUS, also co-authored the study.
To ground truth this new mechanism, the researchers compared their models to a dataset collected in 2016 in which scientists dug a hole in Greenland’s firn and heavily equipped it with thermometers and radar that could measure the movement of meltwater. While previous hydrological models deviated from the measurements, the new mechanism successfully mirrored observations.
An unexpected finding of the new work was that the location of the ice layers may act as a record of the thermal conditions under which they formed.
“In the warming scenario, we found that the ice layers form deeper and deeper into the firn chronologically in a top-down fashion,” said Shadab. “And in a colder condition, ice layers form closer to the surface in a bottom-up scenario.”
Today, the amount of water running into the sea from Greenland currently outpaces Antarctica’s, about 270 billion tons per year compared to Antarctica’s 140 billion tons. Together, that’s more than two and a half Lake Tahoe’s worth each year. But future predictions of how much the two ice sheets will contribute to sea level rise are highly variable, fluctuating from 5 to 55 centimeters by 2100. And it’s clear ice layers play a key, and until now, poorly understood role.
“Things are much more complex in reality than what has been captured by existing models,” said Adhikari. “If we really want to improve our predictions, this is where we’re really advancing the state of the art.”
A Mechanism for Ice Layer Formation in Glacial Firn
Greenland landslide-induced tsunami produced global seismic signal that lasted 9 days
American Association for the Advancement of Science (AAAS)
In 2023, a massive rockslide in East Greenland, driven by glacial melt, triggered a towering tsunami and a rare global seismic signal that resonated for nine days, according to a new study. The study provides insights into how climate change-induced events like glacial thinning can lead to significant geophysical phenomena with impacts extending throughout the Earth system. Due to climate change, steep slopes are increasingly vulnerable to landslides. In Arctic regions – which are undergoing the most rapid warming globally – landslides can be driven by glacial debuttressing, permafrost degradation, and altered precipitation patterns. These landslides can trigger large and destructive tsunamis, particularly when they occur in confined water bodies like fjords. Such events have been recorded around the globe, including recently in West Greenland. Large tsunamigenic landslides produce long-period seismic waves, which can be detected remotely, and their tsunamis may create standing waves known as seiches, in which water sloshes back and forth at a specific resonant frequency. Seiches create long-period, monochromatic signals useful for studying energy transfer between the hydrosphere and the solid Earth. However, current observations of seiches have been limited to short-duration effects recorded by local seismometers. What’s more, numerical modeling of tsunami-induced seiches is limited, leaving a gap in understanding of how climate change can cause cascading, hazardous feedbacks between the cryosphere, hydrosphere, and lithosphere. Here, Kristian Svnnevig and colleagues report data from a significant landslide event in East Greenland that occurred in September 2023, which produced a very-long-period seismic signal that was detected globally for nine days. The event, which was triggered by glacial thinning, led to a massive rock-ice avalanche into Dickson Fjord, generating a 200-meter-high tsunami. This tsunami stabilized into a 7-meter-high long-duration seiche with a 90-second period, which produced a 10.88 millihertz (mHz) global seismic signal that resonated for nine days. Using a variety of geophysical techniques, Svennevig et al. show that the observed seismic signal was driven by the seiche. The findings further reveal that seiches in narrow fjords can produce long-duration seismic signals without persistent external driving forces, like strong winds or storm events.
A rockslide-generated tsunami in a Greenland fjord rang the Earth for 9 days
Article Publication Date
13-Sep-2024
Climate-change-triggered landslide caused Earth to vibrate for nine days
A landslide in a remote part of Greenland caused a mega-tsunami that sloshed back and forth across a fjord for nine days, generating vibrations throughout Earth, according to a new study involving UCL (University College London) researchers
University College London
image:
From left: before (August 2023) and after (September 2023) photos of the mountain peak and glacier, taken from the fjord.
A landslide in a remote part of Greenland caused a mega-tsunami that sloshed back and forth across a fjord for nine days, generating vibrations throughout Earth, according to a new study involving UCL researchers.
The study, published in the journal Science, concluded that this movement of water was the cause of a mysterious, global seismic signal that lasted for nine days and puzzled seismologists in September 2023.
The initial event, not observed by human eye, was the collapse of a 1.2km-high mountain peak into the remote Dickson Fjord beneath, causing a backsplash of water 200 metres in the air, with a wave up to 110 metres high. This wave, extending across 10km of fjord, reduced to seven metres within a few minutes, the researchers calculated, and would have fallen to a few centimetres in the days after.
The team used a detailed mathematical model, recreating the angle of the landslide and the uniquely narrow and bendy fjord, to demonstrate how the sloshing of water would have continued for nine days, with little energy able to escape.
The model predicted that the mass of water would have moved back and forth every 90 seconds, matching the recordings of vibrations travelling in the Earth’s crust all around the globe.
The landslide, the researchers wrote, was a result of the glacier at the foot of the mountain thinning, becoming unable to hold up the rock-face above it. This was ultimately due to climate change. The landslide and tsunami were the first observed in eastern Greenland.
Co-author Dr Stephen Hicks, of UCL Earth Sciences, said: “When I first saw the seismic signal, I was completely baffled. Even though we know seismometers can record a variety of sources happening on Earth’s surface, never before has such a long-lasting, globally travelling seismic wave, containing only a single frequency of oscillation, been recorded. This inspired me to co-lead a large team of scientists to figure out the puzzle.
“Our study of this event amazingly highlights the intricate interconnections between climate change in the atmosphere, destabilisation of glacier ice in the cryosphere, movements of water bodies in the hydrosphere, and Earth’s solid crust in the lithosphere.
“This is the first time that water sloshing has been recorded as vibrations through the Earth’s crust, travelling the world over and lasting several days.”
The mysterious seismic signal – coming from a vibration through the Earth’s crust – was detected by seismometers all over the globe, from the Arctic to Antarctica. It looked completely different to frequency-rich ‘rumbles’ and ‘pings’ from earthquake recordings, as it contained only a single vibration frequency, like a monotonous-sounding hum.
When the study’s authors first discovered the signal, they made a note of it as a “USO”: unidentified seismic object.
At the same time, news of a large tsunami in a remote northeast Greenland fjord reached authorities and researchers working in the area.
The researchers joined forces in a unique multidisciplinary group involving 68 scientists from 40 institutions in 15 countries, combining seismometer and infrasound data, field measurements, on-the-ground and satellite imagery, and simulations of tsunami waves.
The team also used imagery captured by the Danish military who sailed into the fjord just days after the event to inspect the collapsed mountain-face and glacier front along with the dramatic scars left by the tsunami.
It was this combination of local field data and remote, global-scale observations that allowed the team to solve the puzzle and reconstruct the extraordinary cascading sequence of events.
Lead author Dr Kristian Svennevig, from the Geological Survey of Denmark and Greenland (GEUS), said: “When we set out on this scientific adventure, everybody was puzzled and no one had the faintest idea what caused this signal. All we knew was that it was somehow associated with the landslide. We only managed to solve this enigma through a huge interdisciplinary and international effort.”
He added: “As a landslide scientist, an additional interesting aspect of this study is that this is the first-ever landslide and tsunami observed from eastern Greenland, showing how climate change already has major impacts there.”
The team estimated that 25 million cubic metres of rock and ice crashed into the fjord (enough to fill 10,000 Olympic-sized swimming pools).
They confirmed the size of the tsunami, one of the largest seen in recent history, using numerical simulations as well as local data and imagery.
Seventy kilometres away from the landslide, four-metre-high tsunami waves damaged a research base at Ella Ø (island) and destroyed cultural and archaeological heritage sites across the fjord system.
The fjord is on a route commonly used by tourist cruise ships visiting the Greenland fjords. Fortunately, no cruise ships were close to Dickson Fjord on the day of the landslide and tsunami, but if they had been, the consequences of a tsunami wave of that magnitude could have been devastating.
Mathematical models recreating the width and depth of the fjord at very high resolution demonstrated how the distinct rhythm of a mass of water moving back and forth matched the seismic signal.
The study concluded that with rapidly accelerating climate change, it will become more important than ever to characterise and monitor regions previously considered stable and provide early warning of these massive landslide and tsunami events.
Co-author Thomas Forbriger, from Karlsruhe Institute of Technology, said: “We wouldn’t have discovered or been able to analyse this amazing event without networks of high-fidelity broadband seismic stations around the world, which are the only sensors that can truly capture such a unique signal.”
Ground motion visualisation animations showing the very long-period seismic wave propagating around the globe. The left panel shows a ground motion visualisation, showing the seismic wave from the Greenland seiche spreading out around the planet. Each circle shows the data from an individual seismic monitoring station. The right panel shows a numerical simulation of the 16 September 2023 tsunami and seiche in Dickson fjord.
Credit
Music credit: Isabelle Ryder https://isabellerydermusic.weebly.com/; animation credit: Stephen Hicks; Kristian Svennevig; Alexis Marbeouf.
In September 2023, scientists around the world detected a mysterious seismic signal that lasted for nine straight days. An international team of scientists, including seismologists Alice Gabriel and Carl Ebeling of UC San Diego’s Scripps Institution of Oceanography came together to solve the mystery.
A new study published today inScience provides the stunning solution: In an East Greenland fjord, a mountaintop collapsed into the sea and triggered a mega-tsunami about 200 meters (650 feet) tall. The giant wave rocked back and forth inside the narrow fjord for nine days, generating the seismic waves that reverberated through Earth’s crust, baffling scientists around the world. This rhythmic sloshing is a phenomenon known as a seiche. Fortunately, no people were hurt, but the waves destroyed some $200,000 in infrastructure at an unoccupied research station on Ella Island.
“When we set out on this scientific adventure, everybody was puzzled and no one had the faintest idea what caused this signal,” said Kristian Svennevig, a geologist at the Geological Survey of Denmark and Greenland (GEUS) and the study’s lead author. “All we knew was that it was somehow associated with the landslide. We only managed to solve this enigma through a huge interdisciplinary and international effort.”
Climate change set the stage for the landslide by melting the glacier at the base of the mountain, destabilizing the more than 25 million cubic meters (33 million cubic yards) of rock and ice – enough to fill 10,000 Olympic-sized swimming pools – that ultimately crashed into the sea. As climate change continues to melt Earth’s polar regions it could lead to an increase in large, destructive landslides such as this one.
“Climate change is shifting what is typical on Earth, and it can set unusual events into motion,” said Gabriel, whose work on this study was supported by the European Research Council, Horizon Europe, the National Science Foundation (NSF) and NASA.
When seismic monitoring networks first detected this signal in September 2023, it was puzzling for two main reasons. First, the signal looked nothing like the busy squiggle that earthquakes produce on seismographs. Instead, it oscillated with a 92-second-interval between its peaks, too slow for humans to perceive. Second, the signal stayed strong for days on end, where more common seismic events weaken more rapidly.
The global community of Earth scientists started buzzing with online discussion of what could be causing the strange seismic waves. The discussion turned up reports of a huge landslide in a remote Greenland fjord that occurred on Sept. 16, around the time the seismic signal was first detected.
To figure out if and how these two phenomena might be connected, the team, led by Kristian Svennevig of the Geological Survey of Denmark and Greenland, combined seismic recordings from around the world, field measurements, satellite imagery and computer simulations to reconstruct the extraordinary events.
The team, comprised of 68 scientists from 41 research institutions, analyzed satellite and on-the-ground imagery to document the enormous volume of rock and ice in the landslide that triggered the tsunami. They also analyzed the seismic waves to model the dynamics and trajectory of the rock-ice avalanche as it moved down the glacial gully and into the fjord.
To understand the tsunami and resulting seiche, the researchers used supercomputers to create high-resolution simulations of the events.
“It was a big challenge to do an accurate computer simulation of such a long-lasting, sloshing tsunami,” said Gabriel.
Ultimately, these simulations were able to closely match the real-world tsunami’s height as well as the long-lasting seiche’s slow oscillations.
By integrating these diverse data sources, the researchers determined that the nine-day seismic signal was caused by the massive landslide and resulting seiche within Greenland’s Dickson Fjord.
“It was exciting to be working on such a puzzling problem with an interdisciplinary and international team of scientists,” said Robert Anthony, a geophysicist with the United States Geological Survey’s Earthquake Hazards program and co-author of the study. “Ultimately, it took a plethora of geophysical observations and numerical modeling from researchers across many countries to put the puzzle together and get a complete picture of what had occurred.”
The study’s findings demonstrate the complex, cascading hazards posed by climate change in polar regions. While no people were in the area when the landslide and mega-tsunami occurred, the fjord is close to a route commonly used by cruise ships, highlighting the need to monitor polar regions as climate change accelerates. For example, a landslide in western Greenland’s Karrat Fjord in 2017 triggered a tsunami that flooded the village of Nuugaatsiaq, destroying 11 houses and killing four people.
Gabriel said the results could also inspire researchers to comb back through the seismic record to look for similar events now that scientists know what to look for. Finding more seiches could help more clearly define the conditions that give rise to the phenomenon.
“This shows there is stuff out there that we still don’t understand and haven’t seen before,” said Ebeling, who co-authored the study with support from NSF and helped manage a network of seismic sensors that detected the seiche’s vibrations. “The essence of science is trying to answer a question we don’t know the answer to – that’s why this was so exciting to work on.”
'After' image of landslide site
Image of landslide site taken on Sept. 19, 2023 following Sept. 16, 2023 event.
Music credit: Isabelle Ryder https://isabellerydermusic.weebly.com/
Animation credit: Stephen Hicks/University College London
University of California - San Diego
Caption
Left panel shows a ground motion visualization, showing the seismic wave from the Greenland seiche spreading out around the planet. Each circle shows the data from an individual seismic monitoring station. The right panel shows a numerical simulation of the Sept. 16, 2023 tsunami and seiche in Dickson fjord.
