Impact of the revisit frequency on cloud climatology for CALIPSO, EarthCARE, Aeolus, and ICESat-2 satellite lidar missions

Space profiling lidars offer a unique insight into cloud properties in Earth's atmosphere and are considered the most reliable source of total (column-integrated) cloud amount (CA), and true (geometrical) cloud top height (CTH). However, lidar-based cloud climatologies suffer from infrequent sampling: every n days, and only along the ground track. This study therefore evaluated four lidar missions, namely CALIPSO (revisit every n=16 d), EarthCARE (n=25), Aeolus (n=7), and ICESat-2 (n=91), to test the hypothesis that each mission provides accurate data on CA and CTH. CA/CTH values for a hypothetical daily revisit mission were used as reference (data simulated with Meteosat 15 min cloud observations, assumed to be a proxy for ground truth). Our results demonstrated that this hypothesis is invalid, unless individual lidar transects are averaged over an area 10×10∘ in longitude and latitude (or larger). If this is not the case, the required accuracy of 1 % (for CA) or 150 m (for CTH) cannot be met, either for a single-year annual or monthly mean, or for a &gt;10 year climatology. A CALIPSO-focused test demonstrated that the annual mean CA estimate is very sensitive to infrequent sampling, and that this factor alone can result in 14 % or 7 % average uncertainty with 1 or 2.5∘ resolution data, respectively. Consequently, applications that use gridded lidar data should consider calculating confidence intervals, or a similar measure of uncertainty. Our results suggest that CALIPSO, and its follow-on mission EarthCARE, are very likely to produce consistent cloud records despite the difference in sampling frequency.</p

Fluctuations in methane and carbon dioxide concentrations in the nearsurface zone and their genetic characterization in abandoned and active coal mines in the SW part of the Upper Silesian Coal Basin, Poland

The objective of this paper is to determine the origin and variability of methane and carbon dioxide concentrations in the near-surface zone and of coalbed methane in the SW part of the Chwałowice Trough and adjacent areas of the Main Syncline of the Upper Silesian Coal Basin (USCB). For this purpose soil-gas samples were taken at 202 measuring points, arranged along 5 profiles located in the mining area of the abandoned 1 Maja mine and directly adjacent areas as well as in the vicinity of four abandoned and remediated mining shafts. The maximum methane and carbon dioxide concentrations in the gas samples measured exceeds 22 and 9 vol%, respectively. The carbon isotope composition of methane and carbon dioxide was determined in samples in which elevated concentrations of these gases were found. Moreover, seven coalbed gas samples and bituminous coals were collected from coal seams exclusively from virgin parts of the Anna, Marcel, Jastrzębie, and Zofiówka mines. These data were supplemented with results of archival research for genetic interpretation of coalbed gases. Research reveals that typical humic low- and medium-volatile bituminous coals occur in Mississippian and Pennsylvanian coal-bearing strata in the study area. Fluctuations in methane and carbon dioxide concentration in the near-surface zone are related to the lithostratigraphy and tectonics of the area as well as to complicated methane depth distribution. Faults may play an important role in the microseepage of gases from deep to the near-surface zone. The connection of near-surface gases with subsurface gases was confirmed by similar stable carbon isotope composition in the methane recorded in the soil-gas samples and in the gas samples from the coal seams and sandstones of the Carboniferous formations. Distribution of anomalous methane concentrations recorded in soil-gas samples taken from profiles may indicate natural gas accumulations in the top zone of the Pennsylvanian coal-bearing formations. One example of this kind of accumulation is the Marklowice natural gas field, located within the mining area of the Marcel coal mine. Relatively high methane concentrations measured in soil gas in the vicinity of shafts I and III indicate that the degassing systems of closed and remediated mining shafts are not fully effective. Increases in carbon dioxide concentrations in the surface zone and frequent associated decreases in methane concentration were most often the result of microbial methane oxidation

"I'm just as rock 'n' roll fan": popular music as a meaning resource for aging = "Sou como fã de rock 'n' roll": música popular como recurso de significado para o envelhecimento

Tanto críticos quanto fãs têm tradicionalmente encarado a música popular, especialmente em termos de suas interações de rock ´n´ roll, como um recurso de significado da juventude navegando ao longo da adolescência. O objetivo deste artigo é discutir a relevância da música popular para a auto-identidade ao longo da meia-idade e adiante. A base teórica para esta discussão é uma síntese de idéias sobre envelhecimento a partir do existencialismo e do interacionismo simbólico. O pensamento social existencial nos diz que o processo de auto-desenvolvimento é uma constante ao longo da vida. O que muda são circunstâncias da vida, o processo de idade biológica e afetiva, reavaliação do passado e relações estratégicas com os outros. A geração "baby boomer" foi a primeira geração ocidental a crescer inteiramente no mundo da música e da cultura do rock ´n´ roll, e muitos baby boomers vivenciaram o rock ´n´ roll como roteiro padrão para a vida. Por isso, esta fonte cultural altamente auto-integrativa, reforçada pelo poder dos meios de comunicação de massa, continua a ser central para a auto-identidade de muitos baby-boomers idosos mantém o rock ´n´ roll em suas vidas, com um interesse profundo pela autenticidade da sua música. Exemplos incluem a compra e execução de rádio por satélite e outras tecnologias que reforçam o status; o uso de música rock para cultivar romantismo e intimidade; apreço pela música pop em atividades religiosas e durante experiências espirituais; o uso do rock para expressar temas políticos e ser avôs por intermédio de Hannah Montan

Experience with the Quality Assurance of the Superconducting Electrical Circuits of the LHC Machine

The coherence between the powering reference database for the LHC and the Electrical Quality Assurance (ELQA) is guaranteed on the procedural level. However, a challenge remains the coherence between the database, the magnet test and assembly procedures, and the connection of all superconducting circuits in the LHC machine. In this paper, the methods, tooling, and procedures for the ELQA during the assembly phase of the LHC will be presented in view of the practical experience gained in the LHC tunnel. Some examples of detected polarity errors and electrical non-conformities will be presented. The parameters measured at ambient temperature, such as the dielectric insulation of circuits, will be discussed

The effect of Fe, Co, and Ni structural promotion of cryptomelane (KMn8O16)(KMn_8O_{16}) on the catalytic activity in oxygen evolution reaction

Transition metal (Fe, Co, Ni)-doped cryptomelane materials (K-OMS-2) were synthesized and characterized with the use of XRD, Raman spectroscopy, XPS, N2-BET, H2-TPR, and SEM. The electrocatalytic reactivity in oxygen evolution was evaluated with the use of the rotating disk electrode. It was found that the electrocatalytic activity is substantially enhanced for the cobaltdoped material, while iron and nickel doping have no, or even, negative effect on K-OMS-2. The structure of the material bulk is preserved in all cases, but the formation of additional birnessite phases can be evidenced for the iron and cobalt dopants. It is discussed that the reactivity enhancement of Co/K-OMS-2 can be related not only to the formation of cobalt-doped heterophases (cobaltane, birnessite) but also to the changes of the properties of pristine cryptomelane

Carbon-based composites as electrocatalysts for oxygen evolution reaction in alkaline media

13 figures, 5 tables.-- This article belongs to the Special Issue Electrocatalysts for Sustainable Energy and Chemical Synthesis ApplicationsThis review paper presents the most recent research progress on carbon-based composite electrocatalysts for the oxygen evolution reaction (OER), which are of interest for application in low temperature water electrolyzers for hydrogen production. The reviewed materials are primarily investigated as active and stable replacements aimed at lowering the cost of the metal electrocatalysts in liquid alkaline electrolyzers as well as potential electrocatalysts for an emerging technology like alkaline exchange membrane (AEM) electrolyzers. Low temperature electrolyzer technologies are first briefly introduced and the challenges thereof are presented. The non-carbon electrocatalysts are briefly overviewed, with an emphasis on the modes of action of different active phases. The main part of the review focuses on the role of carbon–metal compound active phase interfaces with an emphasis on the synergistic and additive effects. The procedures of carbon oxidative pretreatment and an overview of metal-free carbon catalysts for OER are presented. Then, the successful synthesis protocols of composite materials are presented with a discussion on the specific catalytic activity of carbon composites with metal hydroxides/oxyhydroxides/oxides, chalcogenides, nitrides and phosphides. Finally, a summary and outlook on carbon-based composites for low temperature water electrolysis are presented.This study was financially supported by the National Science Center, Poland, project number 2020/37/B/ST5/01876.Peer reviewe

Automatic System for the D.C. High Voltage Qualification of the Superconducting Electrical Circuits of the LHC Machine

A d.c. high voltage test system has been developed to verify automatically the insulation resistance of the powering circuits of the LHC. In the most complex case, up to 72 circuits share the same volume inside cryogenic lines. Each circuit can have an insulation fault versus any other circuit or versus ground. The system is able to connect up to 80 circuits and apply a voltage up to 2 kV D.C. The leakage current flowing through each circuit is measured within a range of 1 nA to 1.6 mA. The matrix of measurements allows characterizing the paths taken by the currents and locating weak points of the insulation between circuits. The system is composed of a D.C. voltage source and a data acquisition card. The card is able to measure with precision currents and voltages and to drive up to 5 high voltage switching modules offering 16 channels each. A LabVIEW application controls the system for an automatic and safe operation. This paper describes the hardware and software design, the testing methodology and the results obtained during the qualification of the LHC superconducting circuits

Measurement of the Luminosity in the ZEUS Experiment at HERA II

The luminosity in the ZEUS detector was measured using photons from electron bremsstrahlung. In 2001 the HERA collider was upgraded for operation at higher luminosity. At the same time the luminosity-measuring system of the ZEUS experiment was modified to tackle the expected higher photon rate and synchrotron radiation. The existing lead-scintillator calorimeter was equipped with radiation hard scintillator tiles and shielded against synchrotron radiation. In addition, a magnetic spectrometer was installed to measure the luminosity independently using photons converted in the beam-pipe exit window. The redundancy provided a reliable and robust luminosity determination with a systematic uncertainty of 1.7%. The experimental setup, the techniques used for luminosity determination and the estimate of the systematic uncertainty are reported.Comment: 25 pages, 11 figure

Knowing your place and commanding space:de/constructions of gendered embodiment in mixed-sex karate

Feminists have long acknowledged that gendered divisions in access to spaces of leisure, and how women and men physically take up that space, reproduces gender inequality. This article will explore how karate practitioners participate in the space of mixed-sex karate practice and how such uses of space de/construct gendered embodiments and a gender hierarchy. Data presented is drawn from nine months of ethnographic emersion within three karate clubs and fifteen photo-elicitation interviews with karate participants from the three clubs. The findings of this paper suggest that whilst women often occupied spaces of expertise within the karate hall, gendered distinctions in uses of space emerged in the more subtle ways in which women and men used their voice, responded to the tacit and smelt dilemmas of sweat, and moved their bodies across physical space. This research highlights both the potential of physical leisure practice to ‘undo’ conventional gendered embodiments that particularly restrict women’s intentionality in the world (Young, 1980), and the power of spatially-attuned research to illuminate the minute ways in which unequal gender relations are naturalised, legitimised and done

The LHC Continuous Cryostat Interconnections: The Organization of a Logistically Complex Worksite Requiring Strict Quality Standards and High Output

The interconnections of the Large Hadron Collider (LHC) continuous cryostat have been completed in fall 2007: 1695 interconnections magnet to magnet and 224 interconnections between the continuous cryostat and the cryogenic distribution line have been executed along the 27 km of the LHC. The very tight schedule, the complexity of the interconnection sequence, the strict quality standards applied have required the creation of an ad hoc organization in order to steer and coordinate the activities on the worksite dispersed along the whole accelerator ring. The concatenation of construction and test phases carried out by CERN staff, CERN collaborating institutes and contractors have led to the necessity of a common approach and of a very effective information flow. In this paper, after having recalled the main technical challenges, we review the organizational choices that have been taken and we briefly analyze the development of the worksite in term of allocated resources and production