Order of magnitude wall time improvement of variational methane inversions by physical parallelization: a demonstration using TM5-4DVAR

Atmospheric inversions are used to constrain emissions of trace gases using atmospheric mole-fraction measurements. The four-dimensional variational (4DVAR) inversion approach allows optimization of emissions at a higher temporal and spatial resolution than ensemble or analytical approaches but provides limited opportunities for scalable parallelization because it is an iterative optimization method. Multidecadal variational inversions are needed to optimally extract information from the long measurement records of long-lived atmospheric trace gases like carbon dioxide and methane. However, the wall time needed – up to months – complicates these multidecadal inversions. The physical parallelization (PP) method introduced by Chevallier (2013) addresses this problem for carbon dioxide inversions by splitting the period of the chemical transport model into blocks and running them in parallel. Here, we present a new implementation of the PP method which is suitable for methane inversions accounting for the chemical sink of methane. The performance of the PP method is tested in an 11-year inversion using a TM5-4DVAR inversion setup that assimilates surface observations to optimize methane emissions at grid scale. Our PP implementation improves the wall time performance by a factor of 5 and shows excellent agreement with a full serial inversion in an identical configuration (global mean emissions difference =0.06 % with an interannual variation correlation R=0.99; regional mean emission difference &lt;5 % and interannual variation R&gt;0.94). The wall time improvement of the PP method increases with the size of the inversion period. The PP method is planned to be used in future releases of the Copernicus Atmosphere Monitoring Service (CAMS) multidecadal methane reanalysis.</p

BVR photometry of a newly identified RS CVn binary star HD 61396

BVR photometry of a recently identified RS CVn binary star HD61396, carried out during 2001, is presented. The new photometry reveal significant evolution in the shape and amplitude of light curve when compared with those reported earlier by Padmakar etal (2000). The traditional two-starspot model has been used to obtain the spot parameters from the observed light curve. Changes in the spot area and their location on the stellar surface are discernible from the extracted parameters from the new photometry.Comment: 9 pages including 2 figures and 2 tables. New Astronomy in pres

A prospective, single-arm, open-label study to determine the safety and effectiveness of a fixed-dose combination of camylofin and mefenamic acid in Indian women with primary dysmenorrhea

Background: Treatment of dysmenorrhea is aimed at providing symptomatic relief from associated pain. A prospective, single-arm, open-label, multicenter study was conducted at 5 sites across India to assess the safety, effectiveness and tolerability of a fixed-dose combination (FDC) of camylofin 50 mg and mefenamic acid 250 mg in women with primary dysmenorrhea.Methods: Women were prescribed a 3/5-day course of the FDC orally thrice daily. The primary endpoint was to assess the safety of the FDC as analyzed by incidence of adverse events (AEs), and the main secondary endpoint was to evaluate effectiveness by change in mean intensity of pain as assessed by visual analog scale (VAS) scoring from baseline to day 3/5.Results: Out of 274 enrolled women, pain associated with menses was reported by 271 (98.9%) women at baseline. In all, 28 (10.2%) women reported treatment-emergent AEs. The most common AEs were back pain, headache, vomiting, and upper abdominal pain, which were of mild intensity and resolved at the end of treatment (EoT). None of the women discontinued the study due to AEs. No serious AEs or deaths were reported in the study. The mean (standard deviation [SD]) pain intensity on VAS scale was 72.6 (16.28) at baseline and 3.3 (7.11) at EoT. A statistically significant reduction of 69.9 (18.60) from baseline in mean pain intensity was observed after treatment (p<0.0001).Conclusions: An FDC of camyolfin and mefenamic acid had a good safety and tolerability profile and could effectively relieve pain in Indian women with primary dysmenorrhea

Prevalence of malocclusion and orthodontic treatment needs among 12–15-year-old schoolchildren of fishermen of Kutch coast, Gujarat, India

Background: Malocclusion is one of the most common dental problems in mankind. Planning orthodontic treatment as well as an interceptive approach within a public health system requires information on the prevalence of malocclusions.Aim: The aim of the study was to assess the prevalence of malocclusion and orthodontic treatment needs among 12–15-year-old school children of fishermen of Kutch coast, Gujarat, India.Materials and methods: A cross-sectional descriptive survey was conducted among 947 school children offishermen of Kutch coast, Gujarat, India aged 12–15 years. The prevalence of malocclusion and orthodontic treatment needs was assessed using Dental Aesthetic Index. General information on demographic data was also recorded. A c2 test, analysis of variance (ANOVA) and Sheffe’s test were employed for statistical analysis.Results: Malocclusion and orthodontic treatment need was reported among 33.4% of the participants. Younger age group and female gender had significantly greater treatment need. Males and older age groups had significantly lesser prevalence of anterior crowding and largest anterior maxillary irregularity.Conclusions: Orthodontic treatment need among 33.4% calls for developing school based oral health promotion programmes for children with an inculcation of orthodontic treatment and educational programmes for parents (fishermen) addressing prevention and early interceptive treatment of malocclusion

Multicolor Surface Photometry of Lenticulars I. The Data

We present in this paper multicolor surface and aperture photometry in the B, V, R and K' bands for a sample of 34 lenticular galaxies from the UGC catalogue. From surface photometric analysis, we obtain radial profiles of surface brightness, colors, ellipticity, position angle and the Fourier coefficients which describe the departure of isophotal shapes from purely elliptical form and find the presence of dust lanes, patches and ring like structure in several galaxies in the sample. We obtain total integrated magnitudes and colors and find that these are in good agreement with the values from the RC3 catalogue. Isophotal colors are correlated with each other, following the sequence expected for early-type galaxies. The color gradients in lenticulars are more negative than the corresponding gradients in ellipticals. There is a good correlation between B-V and B-R color gradients, and the mean gradient in the B-V, B-R and V-K' colors are -0.13+/-0.06, -0.18+/-0.06, -0.25+/-0.11 magnitude per dex in radius respectively.Comment: 18 pages, 5 figures, uses emulateapj.cls. Accepted for publication in Astronomical Journal, scheduled for February 200

Advancing Scientific Understanding of the Global Methane Budget in Support of the Paris Agreement

The 2015 Paris Agreement of the United Nations Framework Convention on Climate Change aims to keep global average temperature increases well below 2 °C of preindustrial levels in the Year 2100. Vital to its success is achieving a decrease in the abundance of atmospheric methane (CH4), the second most important anthropogenic greenhouse gas. If this reduction is to be achieved, individual nations must make and meet reduction goals in their nationally determined contributions, with regular and independently verifiable global stock taking. Targets for the Paris Agreement have been set, and now the capability must follow to determine whether CH4 reductions are actually occurring. At present, however, there are significant limitations in the ability of scientists to quantify CH4 emissions accurately at global and national scales and to diagnose what mechanisms have altered trends in atmospheric mole fractions in the past decades. For example, in 2007, mole fractions suddenly started rising globally after a decade of almost no growth. More than a decade later, scientists are still debating the mechanisms behind this increase. This study reviews the main approaches and limitations in our current capability to diagnose the drivers of changes in atmospheric CH4 and, crucially, proposes ways to improve this capability in the coming decade. Recommendations include the following: (i) improvements to process‐based models of the main sectors of CH4 emissions—proposed developments call for the expansion of tropical wetland flux measurements, bridging remote sensing products for improved measurement of wetland area and dynamics, expanding measurements of fossil fuel emissions at the facility and regional levels, expanding country‐ specific data on the composition of waste sent to landfill and the types of wastewater treatment systems implemented, characterizing and representing temporal profiles of crop growing seasons, implementing parameters related to ruminant emissions such as animal feed, and improving the detection of small fires associated with agriculture and deforestation; (ii) improvements to measurements of CH4 mole fraction and its isotopic variations—developments include greater vertical profiling at background sites, expanding networks of dense urban measurements with a greater focus on relatively poor countries, improving the precision of isotopic ratio measurements of 13CH4, CH3D, 14CH4, and clumped isotopes, creating isotopic reference materials for international‐scale development, and expanding spatial and temporal characterization of isotopic source signatures; and (iii) improvements to inverse modeling systems to derive emissions from atmospheric measurements—advances are proposed in the areas of hydroxyl radical quantification, in systematic uncertainty quantification through validation of chemical transport models, in the use of source tracers for estimating sector‐level emissions, and in the development of time and spaceresolved national inventories. These and other recommendations are proposed for the major areas of CH4 science with the aim of improving capability in the coming decade to quantify atmospheric CH4 budgets on the scales necessary for the success of climate policies. Plain Language Summary Methane is the second largest contributor to climate warming from human activities since preindustrial times. Reducing human‐made emissions by half is a major component of the 2015 Paris Agreement target to keep global temperature increases well below 2 °C. In parallel to the methane emission reductions pledged by individual nations, new capabilities are needed to determine independently whether these reductions are actually occurring and whether methane concentrations in the atmosphere are changing for reasons that are clearly understood. At present significant challenges limit the ability of scientists to identify the mechanisms causing changes in atmospheric methane. This study reviews current and emerging tools in methane science and proposes major advances needed in the coming decade to achieve this crucial capability. We recommend further developing the models that simulate the processes behind methane emissions, improving atmospheric measurements of methane and its major carbon and hydrogen isotopes, and advancing abilities to infer the rates of methane being emitted and removed from the atmosphere from these measurements. The improvements described here will play a major role in assessing emissions commitments as more cities, states, and countries report methane emission inventories and commit to specific emission reduction targets. </div

Satellite observations reveal extreme methane leakage from a natural gas well blowout

Methane emissions due to accidents in the oil and natural gas sector are very challenging tomonitor, and hence are seldomconsidered in emission inventories and reporting. One of the main reasons is the lack of measurements during such events. Here we report the detection of large methane emissions from a gas well blowout in Ohio during February to March 2018 in the total column methane measurements from the spaceborne Tropospheric Monitoring Instrument (TROPOMI). From these data, we derive a methane emission rate of 120 ± 32 metric tons per hour. This hourly emission rate is twice that of the widely reported Aliso Canyon event in California in 2015. Assuming the detected emission represents the average rate for the 20-d blowout period, we find the total methane emission from the well blowout is comparable to one-quarter of the entire state of Ohio's reported annual oil and natural gas methane emission, or, alternatively, a substantial fraction of the annual anthropogenic methane emissions from several European countries. Our work demonstrates the strength and effectiveness of routine satellite measurements in detecting and quantifying greenhouse gas emission from unpredictable events. In this specific case, the magnitude of a relatively unknown yet extremely large accidental leakage was revealed using measurements of TROPOMI in its routine global survey, providing quantitative assessment of associated methane emissions