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8. Layer separation mapping and consolidation evaluation of a fifteenth century panel painting using terahertz time-domain imaging

Author

Frances E M, Lambert, Jan, Ornik, Naja-Anissa, Staats, Alexander, Jäckel, Goretti G, Hernandez-Cardoso, Jochen, Taiber, Eva-Maria, Stübling, Benjamin, Rudolph, Oliver, Mack, Hans, Portsteffen, Enrique, Castro-Camus, and Martin, Koch

Subjects
Multidisciplinary
Abstract

Over time, artworks often sustain paint layer separation and air gaps within their internal structure due to storage conditions and past restoration efforts. Because of this, paint layer consolidation interventions are an essential activity for art conservators. However, it is difficult to determine the exact location and the extent of layer separation on a piece of art in a non-invasive way, and even more difficult to evaluate the success of a consolidation intervention. In this work, a fifteenth-century wood panel painting was analyzed using terahertz time-domain imaging before and after it was consolidated. Using the terahertz data, it was possible to determine the areas on the artwork in need of consolidation and aid the intervention. The analysis of the after data allowed for the control and determination of the success of the consolidation effort in a non-destructive manner.

Published
2022
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10. Nighttime smartphone use and changes in mental health and wellbeing among young adults: a longitudinal study based on high-resolution tracking data

Author

Agnete Skovlund Dissing, Thea Otte Andersen, Andreas Kryger Jensen, Rikke Lund, and Naja Hulvej Rod

Subjects
Adult, Male, Young Adult, Mental Health, Multidisciplinary, Loneliness, Humans, Longitudinal Studies, Smartphone, Sleep
Abstract

Frequent nighttime smartphone use can disturb healthy sleep patterns and may adversely affect mental health and wellbeing. This study aims at investigating whether nighttime smartphone use increases the risk of poor mental health, i.e. loneliness, depressive symptoms, perceived stress, and low life satisfaction among young adults. High-dimensional tracking data from the Copenhagen Network Study was used to objectively measure nighttime smartphone activity. We recorded more than 250,000 smartphone activities during self-reported sleep periods among 815 young adults (university students, mean age: 21.6 years, males: 77%) over 16 weekdays period. Mental health was measured at baseline using validated measures, and again at follow-up four months later. Associations between nighttime smartphone use and mental health were evaluated at baseline and at follow-up using multiple linear regression adjusting for potential confounding. Nighttime smartphone use was associated with a slightly higher level of perceived stress and depressive symptoms at baseline. For example, participants having 1–3 nights with smartphone use (out of 16 observed nights) had on average a 0.25 higher score (95%CI:0.08;0.41) on the Perceived stress scale ranging from 0 to 10. These differences were small and could not be replicated at follow-up. Contrary to the prevailing hypothesis, nighttime smartphone use is not strongly related to poor mental health, potentially because smartphone use is also a social phenomenon with associated benefits for mental health.

Published
2022
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11. Housing environment and mental health of Europeans during the COVID-19 pandemic: a cross-country comparison

Author

Amélie Keller, Jonathan Groot, Joane Matta, Feifei Bu, Tarik El Aarbaoui, Maria Melchior, Daisy Fancourt, Marie Zins, Marcel Goldberg, Anne-Marie Nybo Andersen, Naja H. Rod, Katrine Strandberg-Larsen, Tibor V. Varga, University of Copenhagen = Københavns Universitet (UCPH), Cohortes épidémiologiques en population (CONSTANCES), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris-Saclay-Université Paris Cité (UPCité), Epidemiology in Dermatology and Evaluation in Therapeutics (EpiDermE), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Institut Pierre Louis d'Epidémiologie et de Santé Publique (iPLESP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU), University College of London [London] (UCL), PRJ-2019-00020, 09‐067124, March of Dimes Foundation, MDF, AstraZeneca, Sundhed og Sygdom, Det Frie Forskningsråd, FSS, DFF: 271‐08‐0839/06‐066023, SSVF 0646, Natur og Univers, Det Frie Forskningsråd, FNU, DFF: DFF—4183‐00152, DFF—4183‐00594, Velux Fonden: 36336, Pfizer Foundation, Merck Sharp and Dohme, MSD, Wellcome Trust, WT: 205407/Z/16/Z, 221400/Z/20/Z, UK Research and Innovation, UKRI: ES/S002588/1, National Health Insurance Administration, NHI, Nuffield Foundation: WEL/FR-000022583, Health Foundation, Cardiff University, Swansea University, Agence Nationale de la Recherche, ANR: -10-COHO-06, -20-COVI-000, ANR-11-INBS-0002, Institut National de la Santé et de la Recherche Médicale, Inserm: 20-26, Københavns Universitet, KU, Fondation pour la Recherche Médicale, FRM: 20RR052-00, Lundbeckfonden: R100‐A9193, Nordea-fonden: 02‐2013‐2014, AU R9‐A959‐13‐S804, Institut National Du Cancer, INCa, Egmont Fonden, H. Lundbeck A/S, This study was made possible by a grant from the RealDania Foundation (PRJ-2019-00020 ‘Indoor environment and child health…’). The DNBC was established with a significant grant from the Danish National Research Foundation. Additional support was obtained from the Danish Regional Committees, the Pharmacy Foundation, the Egmont Foundation, the March of Dimes Birth Defects Foundation, the Health Foundation and other minor grants. Follow‐up of mothers and children has been supported by the Danish Medical Research Council (SSVF 0646, 271‐08‐0839/06‐066023, O602‐01042B, 0602‐02738B), the Lundbeck Foundation (195/04, R100‐A9193), The Innovation Fund Denmark 0603‐00294B (09‐067124), the Nordea Foundation (02‐2013‐2014), Aarhus Ideas (AU R9‐A959‐13‐S804), a University of Copenhagen Strategic Grant (IFSV 2012) and the Danish Council for Independent Research (DFF—4183‐00594 and DFF—4183‐00152). Follow-up of mother and children in the COVID-19 data collection was supported by a grant from the Velux Foundation (grant number 36336, ‘Standing together at a distance—How Danes are living with the Corona Crisis’). The TEMPO cohort received funding from the French National Research Agency (ANR) including the Flash COVID-19 funding scheme, the French Institute for Public Health Research-IReSP (TGIR Cohortes), the French Inter-departmental Mission for the Fight against Drugs and Drug Addiction (MILDeCA), the French Institute of Cancer (INCa), and the Pfizer Foundation. The CONSTANCES COVID-19 Study was funded by: ANR (Agence Nationale de la Recherche, #ANR-20-COVI-000, #ANR-10-COHO-06), Fondation pour la Recherche Médicale (#20RR052-00), Inserm (Institut National de la Santé et de la Recherche Médicale, #C20-26). The CONSTANCES Cohort Study was supported and funded by the French National Health Insurance Fund ('Caisse nationale d’assurance maladie', CNAM). The CONSTANCES Cohort Study is an 'Infrastructure nationale en Biologie et Santé' and benefits from a grant from the French National Agency for Research (ANR-11-INBS-0002). CONSTANCES is also partly funded by Merck Sharp & Dohme (MSD), AstraZeneca, Lundbeck and L’Oréal. None of these funding sources had any role in the design of the study, collection and analysis of data or decision to publish. The Covid-19 Social Study was funded by the Nuffield Foundation [WEL/FR-000022583], but the views expressed are those of the authors and not necessarily the Foundation. The study was also supported by the MARCH Mental Health Network funded by the Cross-Disciplinary Mental Health Network Plus initiative supported by UK Research and Innovation [ES/S002588/1], and by the Wellcome Trust [221400/Z/20/Z]. DF was funded by the Wellcome Trust [205407/Z/16/Z]. The researchers are grateful for the support of a number of organisations with their recruitment efforts including: the UKRI Mental Health Networks, Find Out Now, UCL BioResource, SEO Works, FieldworkHub, and Optimal Workshop. The study was also supported by HealthWise Wales, the Health and Care Research Wales initiative, which is led by Cardiff University in collaboration with SAIL, Swansea University. The funders had no role in the study design, data collection, data analysis, interpretation, the writing of the report, and decisions on where to publish., The authors thank the INSERM-Versailles Saint Quentin en Yvelines University ?Population-based Epidemiologic Cohorts Unit? (Cohortes ?pid?miologiques en population) which designed and manages the Constances Cohort Study. They also thank the National Health Insurance Fund (?Caisse nationale d?assurance maladie des travailleurs salaries,? CNAMTS) and its Health Screening Centres (?Centres d?examens de sant??), which are collecting a large part of the data, as well as the National Old-Age Insurance Fund (Caisse nationale d?assurance vieillesse) for its contribution to the constitution of the cohort, ClinSearch, Asqualab and Eurocell, which are conducting the data quality control., ANR-10-COHO-0006,E4N,Etude Epidémiologique des Enfants de femmes de l'Education Nationale(2010), ANR-11-INBS-0002,CONSTANCES,La cohorte CONSTANCES - Infrastructure épidémiologique ouverte pour la recherche et la surveillance(2011), HAL UVSQ, Équipe, Cohortes - Etude Epidémiologique des Enfants de femmes de l'Education Nationale - - E4N2010 - ANR-10-COHO-0006 - COHO - VALID, and Infrastructures - La cohorte CONSTANCES - Infrastructure épidémiologique ouverte pour la recherche et la surveillance - - CONSTANCES2011 - ANR-11-INBS-0002 - INBS - VALID

Subjects
Family Characteristics, Multidisciplinary, DISORDERS, [SDV]Life Sciences [q-bio], COVID-19, ADULTS, [SDV] Life Sciences [q-bio], Crowding, Mental Health, POOLED ANALYSES, Communicable Disease Control, Housing, Humans, ANXIETY, COHORT, Pandemics, LONELINESS, COMMON, METAANALYSIS
Abstract

Many studies have investigated the impact of the COVID-19 pandemic on mental health. Throughout the pandemic, time spent at home increased to a great extent due to restrictive measures. Here we set out to investigate the relationship between housing conditions and the mental health of populations across European countries. We analyzed survey data collected during spring 2020 from 69,136 individuals from four cohorts from Denmark, France, and the UK. The investigated housing conditions included household density, composition, and crowding, access to outdoor facilities, dwelling type, and urbanicity. The outcomes were loneliness, anxiety, and life satisfaction. Logistic regression models were used, and results were pooled using random-effects meta-analysis. In the meta-analysis, living alone was associated with higher levels of loneliness (OR = 3.08, 95% CI 1.87–5.07), and lower life satisfaction (OR = 1.27, 95% CI 1.05–0.55), compared to living with others. Not having access to an outdoor space and household crowding were suggestively associated with worse outcomes. Living in crowded households, living alone, or lacking access to outdoor facilities may be particularly important in contributing to poor mental health during a lockdown. Addressing the observed fundamental issues related to housing conditions within society will likely have positive effects in reducing social inequalities, as well as improving preparedness for future pandemics.

Published
2022
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12. Holocene polynya dynamics and their interaction with oceanic heat transport in northernmost Baffin Bay

Author

Guillaume Massé, Steffen M. Olsen, Rebecca Jackson, Petra Tallberg, Lukas Wacker, Audrey Limoges, Eleanor Georgiadis, Thorbjørn Joest Andersen, Sofia Ribeiro, Anna Bang Kvorning, Jacques Giraudeau, Naja Mikkelsen, Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Ecosystems and Environment Research Programme, Biosciences, Marine Ecosystems Research Group, Department of Glaciology and Climate, Geological Survey of Denmark and Greenland (GEUS), Department of Earth Sciences, University of New Brunswick, University of New Brunswick (UNB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Danish Meteorological Institute (DMI), Faculty of Biological and Environmental Sciences [Helsinki], Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Station de Biologie Marine de Concarneau, Direction générale déléguée à la Recherche, à l’Expertise, à la Valorisation et à l’Enseignement-Formation (DGD.REVE), Muséum national d'Histoire naturelle (MNHN)-Muséum national d'Histoire naturelle (MNHN), Variabilité de l'Océan et de la Glace de mer (VOG), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Takuvik International Research Laboratory, Université Laval [Québec] (ULaval)-Centre National de la Recherche Scientifique (CNRS), Ion Beam Physics [ETH Zürich], and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)

Subjects
SHELF, 1171 Geosciences, 010506 paleontology, Water mass, 010504 meteorology & atmospheric sciences, Science, Palaeoclimate, 01 natural sciences, Deep sea, Article, Palaeoceanography, PALAEO SEA-ICE, STORFJORDEN, 14. Life underwater, NORTH WATER POLYNYA, ASSEMBLAGES, Roman Warm Period, DEEP-SEA, Holocene, 1172 Environmental sciences, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, BENTHONIC FORAMINIFERA, geography, Multidisciplinary, geography.geographical_feature_category, Sediment, Glacier, GREENLAND, BENTHIC FORAMINIFERA, Oceanography, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Warm water, Medicine, NARES STRAIT, Bay, Geology
Abstract

Baffin Bay hosts the largest and most productive of the Arctic polynyas: the North Water (NOW). Despite its significance and active role in water mass formation, the history of the NOW beyond the observational era remains poorly known. We reconcile the previously unassessed relationship between long-term NOW dynamics and ocean conditions by applying a multiproxy approach to two marine sediment cores from the region that, together, span the Holocene. Declining influence of Atlantic Water in the NOW is coeval with regional records that indicate the inception of a strong and recurrent polynya from ~ 4400 yrs BP, in line with Neoglacial cooling. During warmer Holocene intervals such as the Roman Warm Period, a weaker NOW is evident, and its reduced capacity to influence bottom ocean conditions facilitated northward penetration of Atlantic Water. Future warming in the Arctic may have negative consequences for this vital biological oasis, with the potential knock-on effect of warm water penetration further north and intensified melt of the marine-terminating glaciers that flank the coast of northwest Greenland.

Published
2021
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13. Work stress, anthropometry, lung function, blood pressure, and blood-based biomarkers: a cross-sectional study of 43,593 French men and women

Author

Magnusson Hanson, Linda L., Westerlund, Hugo, Goldberg, Marcel, Zins, Marie, Vahtera, Jussi, Hulvej Rod, Naja, Stenholm, Sari, Steptoe, Andrew, Kivimäki, Mika, Clinicum, Department of Public Health, and University of Helsinki

Subjects
Adult, Male, STRAIN, Adolescent, Health Status, POPULATION-BASED COHORT, lcsh:Medicine, Blood Pressure, SWEDISH MEN, JOB DECISION LATITUDE, Article, Occupational Stress, Young Adult, RISK-FACTOR, Risk Factors, Humans, CORONARY-HEART-DISEASE, Body Weights and Measures, Public Health Surveillance, lcsh:Science, Life Style, Lung, METAANALYSIS, METABOLIC SYNDROME, Aged, lcsh:R, Middle Aged, 3142 Public health care science, environmental and occupational health, EFFORT-REWARD IMBALANCE, Cross-Sectional Studies, Socioeconomic Factors, CARDIOVASCULAR-DISEASE, 3121 General medicine, internal medicine and other clinical medicine, Female, lcsh:Q, France, Biomarkers
Abstract

Work stress is a risk factor for cardio-metabolic diseases, but few large-scale studies have examined the clinical profile of individuals with work stress. To address this limitation, we conducted a cross-sectional study including 43,593 working adults from a French population-based sample aged 18-72 years (the CONSTANCES cohort). According to the Effort-Reward Imbalance model, work stress was defined as an imbalance between perceived high efforts and low rewards at work. A standardized health examination included measures of anthropometry, lung function, blood pressure and standard blood-based biomarkers. Linear regression analyses before and after multivariable adjustment for age, socioeconomic status, depressive symptoms, health-related behaviours, and chronic conditions showed that work stress was associated with higher BMI, waist circumference, waist-hip ratio, alanine transaminase, white blood cell count and lower high-density lipoprotein cholesterol in men, and with higher BMI and white blood cell count in women (differences 0.03-0.06 standard deviations, P

Published
2017
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14. Anomalous variations of VLF sub-ionospheric signal and Mesospheric Ozone prior to 2015 Gorkha Nepal Earthquake

Author

Kondapalli Niranjan Kumar, D. V. Phanikumar, K. Venkatesham, Rajesh Singh, Ajeet K. Maurya, Som Sharma, and Manish Naja

Subjects
Multidisciplinary, Ozone, 010504 meteorology & atmospheric sciences, Anomaly (natural sciences), Terminator (solar), lcsh:R, lcsh:Medicine, Context (language use), 010502 geochemistry & geophysics, 01 natural sciences, Article, Indian subcontinent, chemistry.chemical_compound, chemistry, lcsh:Q, Ionosphere, Natural disaster, lcsh:Science, Geology, Aftershock, Seismology, 0105 earth and related environmental sciences
Abstract

The subject of pre-earthquake ionospheric signatures has always been contentious and debatable. Some of the previous reports have documented unforeseen and unusual variations in some of the atmospheric and ionospheric parameters well before an earthquake. Here, we analyze the ionospheric response from the Indian Subcontinent to Nepal Gorkha Earthquakes occurred between April and May 2015, which were the most powerful and disastrous natural calamities in past ~80 years over the Himalayan region left ~9000 causalities and more than ~20000 people injured with the property damage of the order of several billion dollars. In view of severe earthquakes occurrences, their prior information on the shorter time scales are warranted for mitigation of associated disasters. Here, we report for the first time, a case which shows a strong link in anomalous variations between VLF sub-ionospheric signal and mesospheric ozone prior to both April 25, 2015 (Mw = 7.8) earthquake and its biggest aftershock on May 12, 2015 (Mw = 7.3). Observations show an unusual variation in VLF signals amplitude /shift in terminator time (TT) strongly linked with positive (negative) mesospheric ozone anomaly in D-region altitudes prior to the Gorkha Nepal earthquakes. It is surmised that simultaneous continuous observations of both VLF waves and mesospheric ozone can be considered as an important tool to identify the prior earthquake signatures in the vicinity of the extremely earthquake-prone zone such as Himalayan region. In this context, the current report opens up a new dimension in lithosphere-atmosphere-ionosphere coupling during the earthquake preparation processes itself.

Published
2018

15. Self-reported and tracked nighttime smartphone use and their association with overweight and cardiometabolic risk markers

Author

Thea Otte Andersen, Christoffer Sejling, Andreas Kryger Jensen, Agnete Skovlund Dissing, Elin Rosenbek Severinsen, Henning Johannes Drews, Thorkild I. A. Sørensen, Tibor V. Varga, and Naja Hulvej Rod

Subjects
Medicine, Science
Abstract

Abstract Nighttime smartphone use is associated with sleep problems, which in turn have a bidirectional association with overweight. We aim to investigate whether nighttime smartphone use and sleep are related to overweight and metabolic dysfunction in adult populations. We used data from three population samples (aged 16–89) from the SmartSleep Study, which included survey data (N = 29,838), high-resolution tracking data (N = 3446), follow-up data (N = 1768), and cardiometabolic risk markers (N = 242). Frequent self-reported nighttime smartphone use was associated with 51% higher odds (95% CI: 1.32; 1.70) of overweight compared with no use. Tracked nighttime smartphone use was also associated with overweight. Similar results were found for obesity as an outcome. No consistent associations were found between nighttime smartphone use and cardiometabolic risk markers in a small subsample of healthy young women. Poor sleep quality (vs. good sleep quality) was associated with overweight (OR = 1.19, 85% CI: 1.10; 1.28). Overall, frequent nighttime smartphone use was consistently associated with overweight and a higher BMI across diverse population samples. The bidirectional interplay between nighttime smartphone use, sleep, and overweight may create a vicious circle of metabolic dysfunction over time. Therefore, nighttime smartphone use may be a potential target point for public health interventions to reduce overweight at the population level.

Published
2024
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16. Variability of blue carbon storage in arid evaporitic environment of two coastal Sabkhas or mudflats

Author

Zulfa Ali Al Disi, Khaled Naja, Sankaran Rajendran, Hadil Elsayed, Ivan Strakhov, Hamad Al Saad Al-Kuwari, Fadhil Sadooni, Maria Dittrich, and Jassim Abdulla A. Al-Khayat

Subjects
Medicine, Science
Abstract

Abstract Coastal Sabkhas are mudflats found in arid coastal regions that are located within the supratidal zone when high rates of evaporation lead to high salinity. While evaporitic minerals often accumulate underneath the surface, the microbial mats are present on the surface of Sabkhas. Coastal Sabkha, an under-studied ecosystem in Qatar, has the potential to store blue carbon. In the present study, we investigated the carbon storage capacity of two Sabkhas from contrasting geological backgrounds. The spatial and temporal variabilities of the carbon stocks were examined. The results showed that both studied Sabkhas exhibit a considerable potential for soil carbon storage with carbon stocks of 109.11 ± 7.07 Mg C ha−1 and 67.77 ± 18.10 Mg C ha−1 in Dohat Faishakh and Khor al Adaid Sabkha respectively. These values fall within the reported range for carbon stocks in coastal Sabkhas in the region (51–194 Mg C ha−1). Interestingly, the carbon stocks in the sediments of the Sabkhas were higher than those in the sediments of Qatari mangroves (50.17 ± 6.27 Mg C ha−1). These finding suggest that coastal Sabkhas can serve as blue carbon ecosystems in arid environments.

Published
2023
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17. Comparison of ozonesonde measurements in the upper troposphere and lower Stratosphere in Northern India with reanalysis and chemistry-climate-model data

Author

Suvarna Fadnavis, Archana Sagalgile, Sunil Sonbawne, Bärbel Vogel, Thomas Peter, Frank G. Wienhold, Ruud Dirksen, Peter Oelsner, Manish Naja, and Rolf Müller

Subjects
Medicine, Science
Abstract

Abstract The variability and trend of ozone (O3) in the Upper troposphere and Lower Stratosphere (UTLS) over the Asian region needs to be accurately quantified. Ozone in the UTLS radiatively heats this region and cools the upper parts of the stratosphere. This results in an impact on relative humidity, static stability in the UTLS region and tropical tropopause temperature. A major challenge for understanding ozone chemistry in the UTLS is sparse observations and thus the representation of precursor gases in model emission inventories. Here, we evaluate ozonesonde measurements during August 2016 at Nainital, in the Himalayas, against ozone from multiple reanalyses and the ECHAM6-HAMMOZ model. We find that compared to measurements both reanalyses and ECHAM6-HAMMOZ control simulation overestimate ozone mixing ratios in the troposphere (20 ppb) and in the UTLS (55 ppb). We performed sensitivity simulations using the ECHAM6-HAMMOZ model for a 50% reduction in the emission of (1) NOx and (2) VOCs. The model simulations with NOX reduction agree better with the ozonesonde observations in the lower troposphere and in the UTLS. Thus, neither reanalyses nor ECHAM6-HAMMOZ results can reproduce observed O3 over the South Asian region. For a better representation of O3 in the ECHAM6-HAMMOZ model, NOX emission should be reduced by 50% in the emission inventory. A larger number of observations of ozone and precursor gases over the South Asian region would improve the assessment of ozone chemistry in models.

Published
2023
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18. Holocene polynya dynamics and their interaction with oceanic heat transport in northernmost Baffin Bay

Author

Rebecca Jackson, Anna Bang Kvorning, Audrey Limoges, Eleanor Georgiadis, Steffen M. Olsen, Petra Tallberg, Thorbjørn J. Andersen, Naja Mikkelsen, Jacques Giraudeau, Guillaume Massé, Lukas Wacker, and Sofia Ribeiro

Subjects
Medicine, Science
Abstract

Abstract Baffin Bay hosts the largest and most productive of the Arctic polynyas: the North Water (NOW). Despite its significance and active role in water mass formation, the history of the NOW beyond the observational era remains poorly known. We reconcile the previously unassessed relationship between long-term NOW dynamics and ocean conditions by applying a multiproxy approach to two marine sediment cores from the region that, together, span the Holocene. Declining influence of Atlantic Water in the NOW is coeval with regional records that indicate the inception of a strong and recurrent polynya from ~ 4400 yrs BP, in line with Neoglacial cooling. During warmer Holocene intervals such as the Roman Warm Period, a weaker NOW is evident, and its reduced capacity to influence bottom ocean conditions facilitated northward penetration of Atlantic Water. Future warming in the Arctic may have negative consequences for this vital biological oasis, with the potential knock-on effect of warm water penetration further north and intensified melt of the marine-terminating glaciers that flank the coast of northwest Greenland.

Published
2021
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