Latin Americans with greater Native American ancestry more susceptible to liver failure

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

 

IMAGE: EF CLIF INFOGRAPHIC SHOWING RESULTS OF THE ACLARA STUDY IN LATIN AMERICA view more 

CREDIT: EF CLIF

Differences in the percentage of Native American ancestry in Latin American people are linked with the chances of them developing severe liver failure and associated high risk of short-term mortality, a study co-authored by UCL has found.

The ACLARA study, published in Gastroenterology, is the first of its kind to indicate that ancestry and race may determine the outcome of advanced liver disease (decompensated cirrhosis) in patients.

The large prospective observational study, co-authored by Professor Rajiv Jalan (UCL Division of Medicine), found a high prevalence of severe acute-on-chronic liver failure (ACLF) and high risk of 28-day mortality in liver disease patients that had a greater percentage of Native American ancestry and reported race than those of European and African descent.

The study also found socio-economic factors are associated with the probability of developing ACLF in the Latin American population, with those able to afford private treatment less likely to develop the condition.

Co-author Professor Rajiv Jalan (UCL Division of Medicine) said: “The data generated in the ACLARA study provides the first indication for the important association of Native American race and ancestry in the development of liver failure and its associated mortality.

“It appears that the mechanism of this susceptibility is markedly higher systemic inflammation, which is a central operative mechanism of liver failure. These data have implications for initiating more intense screening programmes for liver disease in this population and further research to understand their susceptibility to other diseases and the mechanisms underlying increased inflammation.”

According to a recent study (Global burden of liver disease: 2023 update), liver disease accounts for more than two million deaths annually (cirrhosis, viral hepatitis, and liver cancer) and for 4% of all deaths worldwide (one out of every 25 deaths). One in three liver-related deaths occurs among females.

Liver cirrhosis mortality in Mexico was the highest in Latin America in 2010, with a mortality rate of 38.3 per 100,000.

A previous large study in Europe, CANONIC, identified ACLF as a distinct syndrome that develops in 30% of patients with acute decompensation of cirrhosis.

Clinical features of ACLF are failure of multiple organs including the liver, kidneys, brain, heart, lungs, blood clotting and a high risk of infection. Recovery from ACLF, either using intensive care or liver transplantation, can normalise the function of these organs.

To gain further insight into the relationship between genetic ancestry, race and the probability of developing ACLF and associated risk of short-term mortality, researchers studied hospitalised cirrhosis patients from seven countries across Latin America.

Latin American populations have varying percentages of genetic variants of Native American, African and European ancestry, as a result of a long history of modern human migrations and admixture (genetic exchange among people of different descent).

The ACLARA study was carried out in 1,274 patients non-electively hospitalized for acute decompensation of cirrhosis in 44 university hospitals, from 27 cities across Argentina, Brazil, Chile, Colombia, Mexico, Paraguay, and Peru.

The study group reported ACLF of any grade in 31.0% of patients at enrolment. Of these, 54.2% presented with ACLF grade 1, 24.9% had ACLF grade 2, and 20.9% had ACLF grade 3 (meaning three or more organ failures).

In addition to genetic ancestry, race was assessed by the physician at hospital admission. Researchers assessed genetic ancestry with the use of genetic markers of ancestry, and not by parental indicators of ancestry.

Overall, patients admitted to hospital with ACLF showed a higher percentage of Native American ancestry and a lower percentage of European ancestry compared to patients with acute decompensation of cirrhosis without ACLF (22.6% and 53.4% vs. 12.9% and 59.6%, respectively).

The percentage of African ancestry was low in both hospitalised patients with ACLF and patients without ACLF among participating countries (6.9% vs. 6.5%).

First author Alberto Farias (Principal Investigator, Hospital das Clínicas, University of São Paulo School of Medicine, Brazil) said: “Investigating ACLF in other cohorts may strengthen the understanding of other upstream factors on disease expression. The Latin American region, with different racial and genetic ancestries, is a unique landscape for in-depth assessment of such factors.”

ACLARA was funded by the European Foundation for the Study of Chronic Liver Failure (EF CLIF), of which Professor Jalan is Scientific Director.

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JOURNAL

Gastroenterology

DOI

10.1053/j.gastro.2023.05.033 

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Genetic Ancestry, Race, and Severity of Acutely Decompensated Cirrhosis in Latin America

Daylight Saving Time saves lives and could save money, confirms Surrey study

Peer-Reviewed Publication

UNIVERSITY OF SURREY

Fewer serious road accidents occur when we enter Daylight Saving Time (DST), according to new research from the University of Surrey, which analysed a decade's worth of data.  

The research found a dramatic 15-20% reduction in serious road accidents during the days close to the Spring DST transition. This reduction is driven by fewer accidents occurring between 6 pm and 9 pm because drivers had an hour more of sunlight.  

 Analogously, the team also found that leaving DST in the Autumn increases minor road accidents by 13%. This is mainly due to more minor accidents happening during the evening hours between 3 pm and 6 pm when an hour of sunlight is reallocated back to the morning.  These findings support the hypothesis that drivers are more sensitive to road lighting conditions rather than to the possible sleep deprivation brought about by the artificial DST clock changes.   

Dr Giuseppe Moscelli, Associate Professor in Economics and co-author of the study from the University of Surrey, said: 

 "Our analysis suggests that changes in road accidents are not influenced by factors such as fuel prices or road usage but by lighting conditions. It begs the question of whether improving artificial lighting conditions in accident hotspots could improve outcomes for drivers." 

The research draws on data from road accident reports in Greece, between 2006 and 2016. The reports are often completed by police officers inspecting crashes and include information on the date, time, location, accident type, and severity (fatal, serious, or minor). 

The study also conducted an economic analysis of the financial cost of these accidents during seasonal clock changes using insurance claims data from the Hellenic Association of Insurance Companies.  

Dr Giuseppe Moscelli explained:  

"Not transitioning back to Standard Time in the Autumn and keeping that extra hour of sunlight appears to not only be a lifesaver, but cost-effective for the taxpayer. Abolishing DST could lead to cost savings of approximately €7.5 million per year during the Spring transition because of the decrease in serious accidents during the additional evening daylight hour provided by DST." 

The research has been published in Health Economics. 

### 

Notes to editors

• Dr Moscelli is available for interview upon request.  

• For more information please contact the University of Surrey's press office via mediarelations@surrey.ac.uk 

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JOURNAL

Health Economics

DOI

10.1002/hec.4715 

ARTICLE TITLE

Summertime and the drivin’ is easy? Daylight saving time and vehicle accidents

Veterinary: Dog bites may be more common on hot and polluted days

Peer-Reviewed Publication

SCIENTIFIC REPORTS

Dog bites may occur more frequently — by up to eleven percent — on days with hotter, sunnier weather, and when air pollution levels are higher, suggests a paper published in Scientific Reports. However, the authors caution that more data and further research is needed to confirm these findings.

Previous research has documented that hotter weather and higher levels of air pollution can be associated with increased aggression in humans, Rhesus monkeys, rats, and mice. However, it is unclear whether dog aggression against humans also follows this trend.

Clas Linnman and colleagues examined data on dog bites in eight US cities — Dallas, Houston, Baltimore, Baton Rouge, Chicago, Louisville, Los Angeles, and New York City — between 2009 and 2018. The data was either drawn from publicly available repositories recorded by animal control authorities or based on previous dog bite compilations. This included 69,525 reported dog bites, an average of three bites per day over ten years. The authors examined the association between dog bite rates and daily levels of fine particulate matter (PM2.5), ozone, and temperature. They also assessed UV and precipitation levels.

The authors report that dog bite incidence increased by eleven percent on days with higher UV levels, by four percent on days with higher temperatures, and by three percent on days with increased levels of ozone. In contrast, dog bite incidence slightly decreased (by one percent) on days with higher levels of rainfall. The authors reported no changes to dog bite incidence on days with higher levels of PM2.5.

The authors caution that the dog bite records did not include information about other factors that can affect an individual dog’s risk of biting, such as dog breed, sex, or whether the dog had been neutered or spayed. Additionally, no information about prior interactions between the dog and the bite victim, such as whether the individual was familiar with the dog, were available.

The authors conclude that these findings appear to expand the association between higher temperatures and levels of air pollution and aggression across species to include dogs. However, further research is needed to confirm and explore this relationship.

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JOURNAL

Scientific Reports

DOI

10.1038/s41598-023-35115-6 

ARTICLE TITLE

The risk of being bitten by a dog is higher on hot, sunny, and smoggy days

ARTICLE PUBLICATION DATE

15-Jun-2023

University of Houston researcher awarded $1.2m grant to assess impacts of biomass burning on Texas air quality

Team to study properties of particulate matter to determine their source and impact on high ozone

Grant and Award Announcement

UNIVERSITY OF HOUSTON

 

IMAGE: AIR QUALITY MONITORING LAB EQUIPMENT AT THE TEAM'S SITE IN GALVESTON, TEXAS. view more 

CREDIT: UNIVERSITY OF HOUSTON

James Flynn, research associate professor at the University of Houston, has been awarded a $1.2 million research grant by the Texas Commission on Environmental Quality. The award will support Flynn and his team’s research project aimed at assessing the impacts of biomass burning, wind-blown dust pollutants and soot on air quality in Texas. Biomass burning can include wildfires, agricultural burning, prescribed burns, etc.

Flynn, principal investigator, and his team will primarily focus on urban air quality in major Texas cities including Houston, Dallas-Fort Worth and El Paso, conducting measurements during the 2023 Texas ozone season (roughly April 1 – October 31) using optical instruments.

“Smoke in particular has been linked to high ozone episodes,” said Flynn, a faculty member of the College of Natural Sciences and Mathematics’ Department of Earth and Atmospheric Sciences. “Along with the fine particulate matter (PM 2.5) in smoke, there are also gases in the smoke that form ozone. By looking at the optical properties of the fine particles, we can determine what is soot or dust or smoke, so we can then identify high ozone periods that have been impacted by smoke.”

Rebecca Sheesley, Professor of Environmental Science at Baylor University is co-investigator of the project, along with fellow Baylor professor, Sascha Usenko. She explains just how far pollutants can move from one place to another.

“Wildfire and dust pollutants can travel very long distances – across the US, across international borders and even across the ocean,” she said.

Recent examples include dark orange skies in New York City due to Canadian wildfires, hazy Houston days because of Saharan dust and blankets of dust in El Paso from desert windstorms.

The research group will use instruments including state-of-the-art tricolor absorption photometers and a nephelometer, which will enable the precise measurement of particulate matter and their optical properties. These instruments will be complemented by advanced air quality monitoring equipment, including trace gas detectors and high-volume filter samplers.

“Filter samples from particles can be analyzed for tracers of indicators of biomass burning,” Flynn said. “Certain filters will be analyzed using radiocarbon dating. This method can tell us the difference between carbon that comes from biomass burning and carbon that’s from fossil fuel burning, like that from power plants and vehicles.”

High Ozone Levels: Local Causes or Not?

Their work could provide clarity to policy makers as to the cause of high ozone. If ozone is coming in with smoke plumes from biomass burning from another state, then it’s not being locally generated; it’s not coming from Houston activity, whether it’s people driving cars, power plants or refineries.

The research team will also collect data on meteorological parameters and carbon monoxide levels to gain a comprehensive understanding of air quality dynamics.

The team will have three monitoring sites in the Houston area: one at the Galveston airport, another in Aldine and one in Liberty County. In Dallas-Fort Worth, the team will have sites at a northwest Fort Worth TCEQ site and the Arlington Municipal Airport. In El Paso, the team is working with the University of Texas at El Paso to reestablish a monitoring site. Flynn’s previous air quality work in El Paso was conducted in conjunction with the UT El Paso.

Air monitoring equipment at the team's site in northwest Fort Worth.

CREDIT

University of Houston

The Air Pollution Complex: improved air pollution understanding in China

Researchers have developed a theoretical framework made up of the latest advances in atmospheric and air pollution science to create a more accurate model of China’s air pollution

Peer-Reviewed Publication

INSTITUTE OF ATMOSPHERIC PHYSICS, CHINESE ACADEMY OF SCIENCES

 

IMAGE: SCHEMATIC SHOWING THE THEORETICAL FRAMEWORK OF THE AIR POLLUTION COMPLEX IN CHINA. view more 

CREDIT: TONG ZHU ET AL.

Air pollution in China is generated from many sources and interacts chemically and physically within the atmosphere in ways that can be difficult to predict.  The concept of the Air Pollution Complex was created to address the underlying complexity of air pollution, and scientists have just recently developed a framework to apply the most current research to air pollution prediction and mitigation strategies.  Here, a group of leading scientists have outlined the most significant progress that has been made in the last two to three years in air pollution research in China.    

China has two main sources of air pollution: coal combustion and vehicle exhaust.  These two components of air pollution, coal smoke and photochemical smog, interact both chemically and physically in complex ways in the atmosphere, creating the Air Pollution Complex.  Researchers in China have spent decades researching the formation mechanisms of the Air Pollution Complex by investigating sources, sinks, transport and transformation processes, and effects of air pollution.  These studies have been integrated into a theoretical framework for the Air Pollution Complex to help scientists better understand, predict and mitigate air pollution in China.  A group of the most prominent scientists in the fields of air pollution and atmospheric chemistry in China summarized the most significant progress that has been made in these fields within the past two to three years. 

The team published their review in the journal Advances in Atmospheric Science. It's one of nine review papers of a special issue on the National Report to the 28th International Union of Geodesy and Geophysics General Assembly to be held on July 11-20, 2023, by the Chinese National Committee of International Association of Meteorology and Atmospheric Sciences. 

“Air pollution, especially the air pollution in China we are facing today, is from multiple emission sources and results from complicated chemical and physical processes in the atmosphere. The Air Pollution Complex has been proposed to comprehensively and holistically understand the complicated nature of air pollution,” said Tong Zhu, first author of the review paper and professor in the College of Environmental Sciences and Engineering at Peking University in Beijing, China.  “This review summarizes the most recent advances of air pollution research in China and how … they contribute to the … theoretical framework of the Air Pollution Complex,” said Zhu.

Creating the framework for the Air Pollution Complex helps atmospheric chemists and air pollution scientists predict air quality hazards and shape environmental policies aimed at controlling and mitigating air pollution in China.  “These tremendous advances in air pollution research have helped establish the theoretical framework of the Air Pollution Complex and describe its complicated and nonlinear feedback nature.  The theoretical framework of Air Pollution Complex is essential to better simulating atmospheric physical and chemical processes which lead to the formation of the Air Pollution Complex, to forecast air pollution with much lower uncertainties and to support air pollution control measures and policies with robust science,” said Zhu. 

The review team outlined the most compelling advances in air pollution and atmospheric chemistry research in China, including air pollution sources and emissions; atmospheric chemistry; effects on the climate, meteorology and the weather; effects on the biosphere, or regions of the earth occupied by living organisms; and mathematical models based on experimental observations.  “The advances of atmospheric chemistry research on the mechanism of air pollution formation … in China have provided robust scientific support to the very successful air pollution control policies implemented in China,” said Zhu.  These successful control measures may additionally benefit low-income and developing countries that likely face similar air pollution challenges.

Zhu and his team understand that a cooperative effort is required to make the most significant impact on worldwide air pollution.  “It is a great challenge in China and across the globe to coordinate carbon emission reduction and air quality improvement to achieve the most benefits for human health.  Atmospheric chemistry research in China should be able to and must make important contributions,” said Zhu.  Future research efforts will focus on the mechanism of the Air Pollution Complex formation to control PM2.5, or particulate matter 2.5 micrometers or less in diameter that negatively impacts human health, and ozone (O3), also known as the main pollutant of photochemical smog.

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JOURNAL

Advances in Atmospheric Sciences

DOI

10.1007/s00376-023-2379-0 

ARTICLE TITLE

Recent Progress in Atmospheric Chemistry Research in China: Establishing a Theoretical Framework for the “Air Pollution Complex”

Cleaner air with a cold catalytic converter

New paper in the prestigious journal Science outlines a new catalyst that can purify exhaust gases at room temperature

Peer-Reviewed Publication

EINDHOVEN UNIVERSITY OF TECHNOLOGY

The so-called three-way catalytic converter in the exhaust system of a car consists of expensive materials and only works correctly when the exhaust gases have a temperature that is several hundred degrees Celsius.

As a result, when you start your car, or when you drive a hybrid car in which the petrol engine and electric motor alternate between driving the powertrain, the gases leaving the exhaust still contain toxic carbon monoxide. In a new Science article, scientists led by Emiel Hensen now show that by modifying the carrier material of the catalyst, it is possible to almost completely convert toxic carbon monoxide into carbon dioxide gas even at room temperature.

Noble needs

Automotive catalysts are made by depositing noble metals such as platinum, palladium, and rhodium on a substrate of the material cerium oxide, which is also known as ceria. However, noble metals are both rare and expensive. Researchers around the world are therefore working on methods to achieve the same or even better catalytic activity through the use of less of these materials.

For example, in a previous paper, Hensen’s group at TU/e proved that by dispersing the noble metal in the form of single atoms leads to not only a reduction in material use, but under certain conditions, the catalyst also functions more efficiently.

New size view
In the PhD research project of lead author Valery Muravev, the researchers shifted their attention from the noble metal to the carrier material underneath (ceria in this case) to further improve the catalysts. They produced the ceria in different crystal sizes and deposited the noble metals as single atoms in the same step. Subsequently, they studied how well these combinations of materials managed to bind an extra oxygen atom to carbon monoxide.

Small ceria crystals of 4 nanometers in size turned out to remarkably improve the performance of the noble metal palladium under cold start conditions in the presence of excess carbon monoxide. This improved performance could be explained by a higher reactivity of the oxygen atoms at smaller ceria crystal sizes. Under more conventional conditions, 8 nanometers turned out to be the optimal size of ceria crystals needed to reach a high catalytic activity at temperatures below 100 degrees Celsius.

Wider significance
This research shows for the first time that when developing catalysts, it pays to look not only at the noble metals that have to do the work. In this case, varying the size of the particles that act as the carrier for the active materials offers an interesting new possibility to further improve catalysts and with those, improve the efficiency and specificity of the chemical reactions. This is also of importance for the development of processes to combine carbon dioxide from ambient air with green hydrogen to produce fuels or compounds for the production of sustainable plastics.

Together with the British company Johnson Matthey, which produces catalysts for the automotive industry, the researchers will now further explore how to translate this finding into new products.

Further information on the paper

Valery Muravev, Alexander Parastaev, Yannis van den Bosch, Bianca Ligt, Nathalie Claes, Sara Bals, Nikolay Kosinov, Emiel J.M. Hensen, Size of ceria support nanocrystals dictates reactivity of highly-dispersed palladium catalysts, Science, (2023).

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JOURNAL

Science

DOI

10.1126/science.adf9082 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Size of cerium dioxide support nanocrystals dictates reactivity of highly-dispersed palladium catalysts

ARTICLE PUBLICATION DATE

16-Jun-2023

Disclaimer: AAAS and

Large uncertainty to persist in projected Southern Ocean sequestration of excess heat from greenhouse warming

Peer-Reviewed Publication

SCIENCE CHINA PRESS

 

IMAGE: THE CIRCUMPOLAR SOUTHERN OCEAN LIES BENEATH SEA ICE AND ICE SHELVES AROUND THE ANTARCTIC MARGINS. THE INTERACTIONS BETWEEN THE OCEAN AND SEA ICE AND ICE SHELVES MAKE THE ANTARCTIC CRYOSPHERE VULNERABLE TO A WARMING SOUTHERN OCEAN. view more 

CREDIT: CREDIT: JINGWEI ZHANG, TAKEN AT PLENEAU ISLAND ON 9 JANUARY 2023.

This study is led by Dr. Wenju Cai (Environment, Commonwealth Scientific Industrial Research Organization, Australia) and involves scientists from China, Australia, and United States. The mid-to-high latitude Southern Ocean (30°S southwards) features prevailing westerly winds, the strongest mean sea-surface winds on Earth, which draws up ocean water from below 2–3 km in a wide circumpolar ring. This circulation system exerts a huge influence on climate under greenhouse warming, because the upwelled water was last in contact with the atmosphere hundreds of years earlier and once brought to the surface, absorbs a vast amount of anthropogenic heat and carbon from the atmosphere. However, based on the latest climate models, even under same emission scenario, inter-model differences in simulated amount of heat absorbed by the Southern Ocean are large, with a ratio of the highest over the lowest as high as three times. “The large spread is a concern, and has huge implications, including for melt of Antarctic Sea ice, ice sheets and ice shelves (center image below), radiative budget of the climate system, hemisphere rainfall distribution, and global sea level rise,” says Dr. Cai.

Dr. Cai and his team sought to determine what causes the large inter-model differences by synthesizing recent advances, and through examination of available outputs from latest models participating in the Phase 6 of Coupled Model Intercomparison Project. The team surveyed a large body of literatures and performed extensive analysis of data from some 30 participating models.

The team found that the large inter-model spread is not simply due to differences in the climate sensitivity, which measures the amount of radiative heating required to raise the Earth surface temperature by 1.0 oC. Previous studies suggest sequestration of heat by the Southern Ocean is mainly through mean circulation that facilitates uptake of additional heating, and that circulation changes because of greenhouse warming play a relatively small role. The new analysis instead shows that circulation changes contribute to much of the inter-model differences beyond that are attributable to climate sensitivity. For example, under greenhouse warming, the prevailing Southern Ocean westerly intensifies toward the Antarctic, but the wind changes are vastly different across models.

The wind intensification induces changes in the intensity and distribution of upwelling, with serious consequences. An increase in upwelling accelerates melt of Antarctic ice sheets and ice shelves, and the associated meltwater flux into the ocean leads to a more stratified   upper ocean, which in turn slows heat and carbon uptake by the Southern Ocean. “There are many such complex interactions at work, some of which are poorly understood and not represented in models, contributing to the large uncertainty.” Cai says.

The researchers also found that the uncertainty can arise from a response of remote process to greenhouse warming, such as El Niño, the most consequential climate variability of the Earth climate. An El Niño is known to induce droughts over the western Pacific countries and floods over the eastern Pacific regions. Less known is that El Niño also leads to weakened prevailing Southern Ocean high-latitude westerlies, which over a warming period affecting shelf ocean warming, melt of sea ice, ice shelves and ice sheets. Surprisingly, inert-model differences in the response of El Niño to greenhouse warming systematically influenced the inter-model differences in Southern Ocean warming. But the changes in El Niño under greenhouse warming itself vastly differs across models. “New perspectives like this add to the growing realization that projecting Southern Ocean warming is one of the most complex issues in climate science.” Cai says.

The study suggests that the science of Southern Ocean warming involves appropriately representing interactions of ice shelves and ice sheets with the warming ocean, interactions of changing circulations with carbon cycles that force the circulation changes in the first place, and polar-tropical interactions, to name just a few. Because each of these areas is a challenge, uncertainty likely persists for some time to come. However, identification of such challenges is a start in any effort to move the science forward.

See the article:

Wenju Cai, Libao Gao, Yiyong Luo, Xichen Li, Xiaotong Zheng, Xuebin Zhang, Xuhua Cheng, Fan Jia, Ariaan Purich, Agus Santoso, Yan Du, David M. Holland, Jia-Rui Shi, Baoqiang Xiang, Shang-Ping Xie. Southern Ocean warming and its climatic impacts. Science Bulletin, 2023, 68(13): 946-960

https://doi.org/10.1016/j.scib.2023.03.049

 

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JOURNAL

Science Bulletin

DOI

10.1016/j.scib.2023.03.049 

10-year countdown to sea-ice-free Arctic

Peer-Reviewed Publication

POHANG UNIVERSITY OF SCIENCE & TECHNOLOGY (POSTECH)

 

IMAGE: - BLACK LINE (UNCONSTRAINED): RAW MODEL PROJECTIONS - RED, BLUE, GREEN LINES: MODEL PREDICTIONS CONSTRAINED BY THREE OBSERVED DATASETS. → THE RESULTS PREDICT THAT ALL OF ARCTIC SEA ICE WILL DISAPPEAR IN THE 2030S IF INCREASES IN GREENHOUSE GAS EMISSIONS REMAIN AT CURRENT RATE, AND EVEN WITH EMISSION REDUCTION, IT WILL EVENTUALLY DISAPPEAR DURING THE 2050S. view more 

CREDIT: POSTECH

If the world keeps increasing greenhouse gas emissions at its current speed, all sea ice in the Arctic will disappear in the 2030s, an event that could at best be postponed until the 2050s should emissions be somehow reduced. The prediction is a decade earlier than what the Intergovernmental Panel on Climate Change (IPCC) has projected: an ice-free Arctic by the 2040s.

 

A possible ice-free Arctic in the 2030-2050s was projected regardless of humanity’s efforts to reduce its greenhouse gas emissions by Professor Seung-Ki Min and Research Professor Yeon-Hee Kim from the Division of Environmental Science and Engineering at Pohang University of Science and Technology (POSTECH) and a joint team of researchers from the Environment Climate Change Canada and Universität Hamburg, Germany. The research was published in the international journal, Nature Communications.

 

The term global warming has become a household name since it was first used by a climate scientist at NASA in 1988. The Earth has seen a rapid decline in the Arctic sea ice area as its temperature has increased over the past several decades. This reduction in Arctic sea ice has induced the acceleration of Arctic warming, which is suggested to contribute to the increased frequency of extreme weather events in mid-latitude regions.
 

 

To predict the timing of Arctic sea ice depletion, the research team analyzed 41 years of data from 1979 to 2019.  By comparing the results of multiple model simulations with three satellite observational datasets, it was confirmed that the primary cause of the decline is attributed to 'man-made greenhouse gas emissions’. Greenhouse gas emissions resulting from human fossil fuel combustion and deforestation have been the primary drivers of Arctic sea ice decline over the past 41 years, while the influence of aerosols, solar and volcanic activities has been found to be minimal.  Monthly analysis found that increased greenhouse gas emissions were reducing Arctic sea ice all year round, regardless of season or timing, although September exhibited the smallest extent of sea ice reduction.

 

Furthermore, it was revealed that climate models used in previous IPCC predictions generally underestimated the declining trend of sea ice area, which was taken into account to adjust the simulation values for future predictions. The results showed accelerated decline rates across all scenarios, most importantly confirming that Arctic sea ice could completely disappear by the 2050s even with reductions in greenhouse gas emissions.  This finding highlights for the first time that the extinction of Arctic sea ice is possible irrespective of achieving ‘carbon neutrality.’

 

The accelerated decline of Arctic sea ice, faster than previously anticipated, is expected to have significant impacts not only on the Arctic region but also on human societies and ecosystems worldwide. The reduction of sea ice can result in more frequent occurrences of extreme weather events such as severe cold waves, heat waves, and heavy rainfalls all across the globe, with the thawing of the Siberian permafrost in the Arctic region possibly intensifying global warming further. We may witness terrifying scenarios, which we have seen only in disaster movies, unfold right before our eyes.

 

Professor Seung-Ki Min, who led the study, explained, “We have confirmed an even faster timing of Arctic sea ice depletion than previous IPCC predictions after scaling model simulations based on observational data.” He added, “We need to be vigilant about the potential disappearance of Arctic sea ice, regardless of carbon neutrality policies.” He also expressed the importance of “evaluating the various climate change impacts resulting from the disappearance of Arctic sea ice and developing adaptation measures alongside carbon emission reduction policies.”

 

 The study was funded by the National Research Foundation of Korea (Mid-Career Researcher program).

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JOURNAL

Nature Communications

DOI

10.1038/s41467-023-38511-8 

ARTICLE TITLE

Observationally-constrained projections of an ice-free Arctic even under a low emission scenario

ARTICLE PUBLICATIO

Scientists discover urea in atmosphere revealing profound consequences for climate

Peer-Reviewed Publication

UNIVERSITY OF MANCHESTER

Areas of the ocean that are rich in marine life are having a bigger impact on our ecosystems and the climate than previously thought, new research suggests.  

Observations made by scientists at The University of Manchester found that the primary source of urea – a nitrogen-rich compound, vital for the growth and development of living organisms - comes from the ocean.  

The observations reveal an important but unaccounted for source of reduced nitrogen and offer the first-ever observations of gaseous urea in the air.  

The research, published in the journal Proceedings of the National Academy of Sciences, also reveals that urea can be transported over long distances through the atmosphere to benefit other environments that may be nutrient-deficient. 

The results could have far-reaching consequences for marine productivity and climate stability.   

Emily Matthews, Atmospheric Scientist at The University of Manchester, said: “Our observations provide new insights into the complex interactions between the atmosphere, ocean and ecosystems.  

“Understanding the behaviour and impact of urea in the atmosphere is vital for advancing our knowledge of how chemicals and substances are transferred through our environment and can help us to inform strategies to address climate change.” 

The observations of gas-phase urea in the atmosphere were collected over the North Atlantic Ocean using the FAAM Airborne Laboratory, a UK airborne research facility managed by the National Centre for Atmospheric Science (NCAS) and owned by UK Research and Innovation and the Natural Environmental Research Council. 

Measurements made during these flights provide detailed data on the composition and properties of aerosols and gases in the atmosphere. Scientists from The University of Manchester and NCAS have identified unique species important to the marine reduced nitrogen cycle, including the first observations of gas-phase urea in the atmosphere. 

The researchers say that the findings have significant implications for our understanding of the nitrogen cycle and calls for a revision of current models.  

Emily Matthews added: “The ocean plays an important role in maintaining a stable climate through biological activity occurring near the surface of the water and contributes to oceanic uptake of carbon dioxide.  

“We now know that it is also a significant source of urea in the atmosphere throughout most of the year, which means we need to modify the processes and factors involved in the nitrogen cycle to account for the newfound importance of urea.” 

The nitrogen cycle is the process during which nitrogen moves through both living organisms and physical environments including the atmosphere, soil, water, plants, animals and bacteria. It is central to the composition of the Earth System and changes of the natural environment through interactions such as aerosol formation, ozone production and as a supply of essential nutrients to living organisms.   

The explanation for the observations of gas phase urea remains a mystery and further research is needed to fully understand biogeochemical coupling of nitrogen between the ocean and atmosphere.  

The research findings represent an important pathway for long range transport of nitrogen to fertise nitrogen poor regions of the surface ocean. Revising this knowledge better helps to understand how the ocean biosphere will respond to future changes. 

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JOURNAL

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2218127120 

ARTICLE TITLE

Airborne observations over the North Atlantic Ocean reveal the importance of gas-phase urea in the atmosphere

ARTICLE PUBLICATION DATE

14-Jun-2023