This paper analyses the changes on the maritime network before and after the Covid-19 outbreak. Using a large sample of vessel movements between ports, we show a decrease in the global maritime connectivity and significant differences between ports and inter-port links. Furthermore, we find that Covid-19 mitigation measures implemented by governments affected regional port hierarchies differently, with a reduction in port concentration in Europe and Africa and an increase in Asia and North America. Globally, very large ports and small but densely inter-connected ones resisted better to the crisis than the others, while small transshipment hubs and bridges appear to have been more negatively impacted. These findings have implications for the design of more resilient port strategies and transport policies by states and firms.
descriptionPublicationkeyboard_double_arrow_right Article 2021 France MDPI AG
Authors: Jean-Baptiste Bouillon-Minois; Vincent Roux; Matthieu Jabaudon; Mara Flannery; +10 Authors
Jean-Baptiste Bouillon-Minois; Vincent Roux; Matthieu Jabaudon; Mara Flannery; Jonathan Duchenne; Maxime Dumesnil; Morgane Paillard-Turenne; Paul-Henri Gendre; Kévin Grapin; Benjamin Rieu; Frédéric Dutheil; Carolyne Croizier; Jeannot Schmidt; Bruno Pereira;
During the first wave of the COVID-19 pandemic, some French regions were more affected than others. To relieve those areas most affected, the French government organized transfers of critical patients, notably by plane or helicopter. Our objective was to investigate the impact of such transfers on the pulse oximetric saturation (SpO2)-to-inspired fraction of oxygen (FiO2) ratio among transferred critical patients with COVID-19. We conducted a retrospective study on medical and paramedical records. The primary endpoint was the change in SpO2/FiO2 during transfers. Thirty-eight patients were transferred between 28 March and 5 April 2020, with a mean age of 62.4 years and a mean body mass index of 29.8 kg/m2. The population was 69.7% male, and the leading medical history was hypertension (42.1%), diabetes (34.2%), and dyslipidemia (18.4%). Of 28 patients with full data, we found a decrease of 28.9 points in SpO2/FiO2 (95% confidence interval, 5.8 to 52.1, p = 0.01) between the starting and the arrival intensive care units (SpO2/FiO2, 187.3 ± 61.3 and 158.4 ± 62.8 mmHg, respectively). Air medical transfers organized to relieve intensive care unit teams under surging conditions during the first COVID wave were associated with significant decreases in arterial oxygenation.
descriptionPublicationkeyboard_double_arrow_right Article 2021 Spain, Italy, Austria, Norway, France, Spain, Norway, Germany American Geophysical Union (AGU) UKRI | The UK Earth system model..., EC | CRESCENDO, EC | 4C
Authors: Chris D. Jones; Jonathan E. Hickman; S. T. Rumbold; Jeremy Walton; +45 Authors
Chris D. Jones; Jonathan E. Hickman; S. T. Rumbold; Jeremy Walton; Robin Lamboll; Ragnhild Bieltvedt Skeie; Stephanie Fiedler; Piers M. Forster; Joeri Rogelj; Manabu Abe; Michael Botzet; Katherine Calvin; Christophe Cassou; Jason N. S. Cole; Paolo Davini; Makoto Deushi; Martin Dix; John C. Fyfe; Nathan P. Gillett; Tatiana Ilyina; Michio Kawamiya; Maxwell Kelley; Slava Kharin; Tsuyoshi Koshiro; Hongmei Li; Chloe Mackallah; Wolfgang A. Müller; Pierre Nabat; Twan van Noije; Paul Nolan; Rumi Ohgaito; Dirk Jan Leo Oliviè; Naga Oshima; José Antonio Parodi; Thomas Reerink; Lili Ren; Anastasia Romanou; Roland Séférian; Yangming Tang; Claudia Timmreck; Jerry Tjiputra; Etienne Tourigny; Kostas Tsigaridis; Hailong Wang; Mingxuan Wu; Klaus Wyser; Shuting Yang; Yang Yang; Tilo Ziehn;
Abstract Many nations responded to the corona virus disease‐2019 (COVID‐19) pandemic by restricting travel and other activities during 2020, resulting in temporarily reduced emissions of CO2, other greenhouse gases and ozone and aerosol precursors. We present the initial results from a coordinated Intercomparison, CovidMIP, of Earth system model simulations which assess the impact on climate of these emissions reductions. 12 models performed multiple initial‐condition ensembles to produce over 300 simulations spanning both initial condition and model structural uncertainty. We find model consensus on reduced aerosol amounts (particularly over southern and eastern Asia) and associated increases in surface shortwave radiation levels. However, any impact on near‐surface temperature or rainfall during 2020–2024 is extremely small and is not detectable in this initial analysis. Regional analyses on a finer scale, and closer attention to extremes (especially linked to changes in atmospheric composition and air quality) are required to test the impact of COVID‐19‐related emission reductions on near‐term climate. Key Points Lockdown restrictions during COVID‐19 have reduced emissions of aerosols and greenhouse gases12 CMIP6 Earth system models have performed coordinated experiments to assess the impact of this on climateAerosol amounts are reduced over southern and eastern Asia but there is no detectable change in annually averaged temperature or precipitation
Due to the current events related to Covid-19, the conference originally planned for July 2020 has been postponed to April 7-9, 2021.The conference will be organized virtually by videoconference. ORAL; International audience; In this paper, a study of UWB receivers in terms of detection theory is presented. The UWB radar which is presented in many works previously - has many applications. For road UWB radar application, the receiver based on correlation is the optimum receiver . In fact, it maximizes the probability of detection. We will consider, in this study, a correlator receiver based on a threshold detection method. As in narrowband  , we will describe the theoretical study that evaluates the performance of the UWB receiver based on correlation in terms of detection and false alarm probabilities. Then a study of curves showing threshold receiver operating characteristics (ROC system), based on correlation and destined to be used for a UWB radar is presented. The study is original because it is presented for the first time in a UWB radar system.
Abstract Micromobility vehicles, and especially free-floating electric scooters (FFES), have been thriving over the past couple of years, Paris being the most important market worldwide. In this paper, we first define micromobility. Then, we present the design and results of an extensive face-to-face road survey among e-scooter (ES) users in Paris (N = 459, F(men) = 68%). Results indicate that ES users rarely own their proper microvehicle, are mostly men, aged 18–29, and have a high educational level. They are not less motorized than the general population and use ES occasionally. Their main motivation is travel time savings followed by playfulness and money savings. However, users seeking money savings are not frequent riders. They shifted mainly from walking and public transportation (72%) and few have increased their total mobility by making new trips (6%). Findings can be useful to researchers, policy makers, and FFES operators especially in the context of COVID pandemics.
Milad Mousazadeh; Biswaranjan Paital; Zohreh Naghdali; Zohreh Mortezania; Marjan Hashemi; Elnaz Karamati Niaragh; Mohammad Aghababaei; Melika Ghorbankhani; Eric Lichtfouse; Mika Sillanpää; Khalid S. Hashim; Mohammad Mahdi Emamjomeh;
International audience; The outbreak of COVID-19 has made a global catastrophic situation that caused 1,039,406 deaths out of 35,347,404 infections, and it will also cause significant socio-economic losses with poverty increasing from 17.1 to 25.9%. Although the spreading rate of COVID-19 is very high on October 6, 2020, the death rate is still less than 2.94%. Nonetheless, this review article shows that the lockdown has induced numerous positive impacts on the environment and on energy consumption. For instance, the lockdown has decreased the electricity demand by 30% in Italy, India, Germany, and the USA, and by 12–20% in France, Germany, Spain, India, and the UK. Additionally, the expenditure of the fuel supply has been decreased by 4% in 2020 as compared to the previous years (2012–2019). In particular, The global demand for coal fuel has been reduced by 8% in March and April 2020 as compared to the same time in 2019. In terms of harmful emissions, the lockdowns reduced the emissions of nitrous oxides by 20–30% in China, Italy, France, Spain, and by 77.3% in São Paulo, Brazil. Similarly, the particulate matter level has been reduced from 5–15% in Western Europe, to 200% in New Delhi, India, which in turn has enhanced the air quality in a never-seen manner in recent times. In some places, such as New York, USA, CO2 emission was also reduced by 5–10%. The water quality, in several polluted areas, has also been remarkably enhanced, for example, the dissolved oxygen content in the Ganga River, India, has increased by about 80%. Traffic congestion has also been reduced worldwide, and in some areas, it has been reduced by 50%, such as New York and Los Angeles, USA. Overall, while the COVID-19 pandemic has shrinked the global economy by 13–32%, the pandemic has also clearly benefited to other sectors, which must be considered as the spotlight for the permanent revival of the global ecosystem.
During the era of COVID-19 (COronaVIrus Disease of 2019), telework has been adopted extensively in developing countries for the first time. This study analyzes data of 355 teleworkers in Hanoi (Vietnam) during April 2020, the period of social distancing, to examine various factors associated with (1) complete home-based telework (HBT), (2) the perception of HBT, and (3) the attitude toward the combination between HBT and conventional work at workplace post-COVID-19. It finds that the company's closure policy and the frequency of working from a distance before the social distancing period were the primary determinants of exclusively teleworking. Regarding the perception of HBT, while the fear of COVID-19 was a strong positive factor, difficulties in focusing on work and accessing data were negative factors. Regarding the attitude toward the future development of HBT, attitudinal factors, commute distance, gender, children in household, and the perception of HBT in the social distancing period were the main predictors. The presence of more than one child negatively affected the perception of telework but positively affected the attitude toward establishing the hybrid work mechanism. The findings suggested that HBT has the potential to alleviate traffic congestion in developing countries and it can be promoted by emphasizing its environment-related benefits. The sample used in this research was collected in the initial stage of constrained mobility and it was not well representative; therefore, this study serves as a proof of concept for ongoing wider analyses on HBT post-COVID-19 or in the subsequent lockdown periods.
descriptionPublicationkeyboard_double_arrow_right Other literature type 2021 French HAL CCSD
Authors: Wang, Wenfei;
Depuis la Convention de Chicago en 1944, l'industrie du transport aérien a maintenu une forte dynamique de croissance, malgré les fluctuations du marché à court terme, dont la dernière a été la pandémie de COVID-19. Cette croissance, soutenue par le développement économique et touristique mondial, s’est traduite par des flux d’échange de services sur le marché international. Les compagnies aériennes dont la stratégie de développement touristique reposait auparavant sur l’intégration verticale et horizontale, se sont tournées vers de nouvelles stratégies basées sur la différenciation et les coûts comparatifs. En effet, la déréglementation dans le transport aérien a joué un rôle clé dans la création de nouvelles dessertes et l’augmentation de la concurrence entre les compagnies sur le marché international. Cette concurrence a favorisé l’émergence de nouvelles stratégies touristiques qui ont participé au développement du tourisme mondial. Since the Chicago Convention in 1944, the airline industry has maintained strong growth momentum, despite short-term market fluctuations, the latest of which was the COVID-19 pandemic. This growth, supported by global economic and tourism development, has resulted in the exchange of services on the international market. Air companies, whose tourism development strategy was previously based on vertical and horizontal integration, have turned to new strategies based on differentiation and comparative costs. Indeed, deregulation in air transport has played a crucial role in creating new routes and increasing competition between airlines in the international market. This competition has encouraged the emergence of new tourism strategies that have contributed to world tourism development.
descriptionPublicationkeyboard_double_arrow_right Article 2020 France, Switzerland, Austria, France, United Kingdom, France, Norway, France, Netherlands, France, Norway, Switzerland, Germany, Norway, United Kingdom, Germany Copernicus GmbH EC | 4C, EC | CRESCENDO, NSF | INFEWS: U.S.-China: Integ...
Authors: P. Friedlingstein; P. Friedlingstein; M. O'Sullivan; M. W. Jones; +99 Authors
P. Friedlingstein; P. Friedlingstein; M. O'Sullivan; M. W. Jones; R. M. Andrew; J. Hauck; A. Olsen; A. Olsen; G. P. Peters; W. Peters; W. Peters; J. Pongratz; J. Pongratz; S. Sitch; C. Le Quéré; J. G. Canadell; P. Ciais; R. B. Jackson; S. Alin; L. E. O. C. Aragão; L. E. O. C. Aragão; A. Arneth; V. Arora; N. R. Bates; N. R. Bates; M. Becker; M. Becker; A. Benoit-Cattin; H. C. Bittig; L. Bopp; S. Bultan; N. Chandra; N. Chandra; F. Chevallier; L. P. Chini; W. Evans; L. Florentie; P. M. Forster; T. Gasser; M. Gehlen; D. Gilfillan; T. Gkritzalis; L. Gregor; N. Gruber; I. Harris; K. Hartung; K. Hartung; V. Haverd; R. A. Houghton; T. Ilyina; A. K. Jain; E. Joetzjer; K. Kadono; E. Kato; V. Kitidis; J. I. Korsbakken; P. Landschützer; N. Lefèvre; A. Lenton; S. Lienert; Z. Liu; D. Lombardozzi; G. Marland; G. Marland; N. Metzl; D. R. Munro; D. R. Munro; J. E. M. S. Nabel; S.-I. Nakaoka; Y. Niwa; Y. Niwa; K. O'Brien; K. O'Brien; T. Ono; P. I. Palmer; P. I. Palmer; D. Pierrot; B. Poulter; L. Resplandy; E. Robertson; C. Rödenbeck; J. Schwinger; J. Schwinger; R. Séférian; I. Skjelvan; I. Skjelvan; A. J. P. Smith; A. J. Sutton; T. Tanhua; P. P. Tans; H. Tian; B. Tilbrook; B. Tilbrook; G. van der Werf; N. Vuichard; A. P. Walker; R. Wanninkhof; A. J. Watson; D. Willis; A. J. Wiltshire; W. Yuan; X. Yue; S. Zaehle;
Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate – the “global carbon budget” – is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (EFOS) are based on energy statistics and cement production data, while emissions from land-use change (ELUC), mainly deforestation, are based on land use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly and its growth rate (GATM) is computed from the annual changes in concentration. The ocean CO2 sink (SOCEAN) and terrestrial CO2 sink (SLAND) are estimated with global process models constrained by observations. The resulting carbon budget imbalance (BIM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the last decade available (2010–2019), EFOS was 9.6 ± 0.5 GtC yr−1 excluding the cement carbonation sink (9.4 ± 0.5 GtC yr−1 when the cement carbonation sink is included), and ELUC was 1.6 ± 0.7 GtC yr−1. For the same decade, GATM was 5.1 ± 0.02 GtC yr−1 (2.4 ± 0.01 ppm yr−1), SOCEAN 2.5 ± 0.6 GtC yr−1, and SLAND 3.4 ± 0.9 GtC yr−1, with a budget imbalance BIM of −0.1 GtC yr−1 indicating a near balance between estimated sources and sinks over the last decade. For the year 2019 alone, the growth in EFOS was only about 0.1 % with fossil emissions increasing to 9.9 ± 0.5 GtC yr−1 excluding the cement carbonation sink (9.7 ± 0.5 GtC yr−1 when cement carbonation sink is included), and ELUC was 1.8 ± 0.7 GtC yr−1, for total anthropogenic CO2 emissions of 11.5 ± 0.9 GtC yr−1 (42.2 ± 3.3 GtCO2). Also for 2019, GATM was 5.4 ± 0.2 GtC yr−1 (2.5 ± 0.1 ppm yr−1), SOCEAN was 2.6 ± 0.6 GtC yr−1, and SLAND was 3.1 ± 1.2 GtC yr−1, with a BIM of 0.3 GtC. The global atmospheric CO2 concentration reached 409.85 ± 0.1 ppm averaged over 2019. Preliminary data for 2020, accounting for the COVID-19-induced changes in emissions, suggest a decrease in EFOS relative to 2019 of about −7 % (median estimate) based on individual estimates from four studies of −6 %, −7 %, −7 % (−3 % to −11 %), and −13 %. Overall, the mean and trend in the components of the global carbon budget are consistently estimated over the period 1959–2019, but discrepancies of up to 1 GtC yr−1 persist for the representation of semi-decadal variability in CO2 fluxes. Comparison of estimates from diverse approaches and observations shows (1) no consensus in the mean and trend in land-use change emissions over the last decade, (2) a persistent low agreement between the different methods on the magnitude of the land CO2 flux in the northern extra-tropics, and (3) an apparent discrepancy between the different methods for the ocean sink outside the tropics, particularly in the Southern Ocean. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set (Friedlingstein et al., 2019; Le Quéré et al., 2018b, a, 2016, 2015b, a, 2014, 2013). The data presented in this work are available at https://doi.org/10.18160/gcp-2020 (Friedlingstein et al., 2020).
Many countries around the world have chosen lockdown and restrictions on people’s mobility as the main strategies to combat the COVID-19 pandemic. These actions have significantly affected environmental noise and modified urban soundscapes, opening up an unprecedented opportunity for research in the field. In order to enable these investigations to be carried out in a more harmonized and consistent manner, this paper makes a proposal for a set of indicators that will enable to address the challenge from a number of different approaches. It proposes a minimum set of basic energetic indicators, and the taxonomy that will allow their communication and reporting. In addition, an extended set of descriptors is outlined which better enables the application of more novel approaches to the evaluation of the effect of this new soundscape on people’s subjective perception.