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China is now the world's largest emitter of CO2. The main cause is the heavy reliance on coal to generate electricity. There is little doubt that coal will continue to dominate the power generation mix for many years and that ever increasing amounts of coal will be needed. Besides replacing old and inefficient coal-fired power plants with new, more efficient ones, the government is trying to reduce the emissions by establishing minimum quality standards for coal used in power generation. However, the demand for coal is such that some power plants have for many years been buying, both legally and illegally, lesser quality coals from Indonesia and Vietnam. The focus of this paper is the potential emissions from the illegally mined coal that ends up at Chinese power plants. [ABSTRACT FROM AUTHOR]

The steady rise in energy demand is expected to continue in Singapore due to the country's economic and population growth. According to projections, electricity generation will increase by some 30% from 2010 to 2025. Despite the rise in demand, Singapore authorities have announced a commitment to reduce carbon emissions by 7-11% below 2020 business-as-usual levels, with a half of reductions coming from the power generation sector. In this study, we examine the average carbon dioxide (CO 2 ) emissions or grid factor of power generation in Singapore, and aim to assess the carbon emissions reduction potential arising from different fuel and generation technology mixes. Adding alternative feedstocks and/or displacing existing generation technologies can have a wide range of consequences on the theoretical grid factor. We show that emissions savings can vary substantially depending on the type of fuel sources that are either added to the mix, or used to displace existing generation feedstocks. The results highlighted in this study provide a Singapore-specific example for targeting medium to longer-term emission savings from the power generation sector. [ABSTRACT FROM AUTHOR]

Coal-fired power generation in Vietnam is expected to grow rapidly over the next 15 years and become the most important source of electricity in Vietnam. At present, coal accounts for about 20% of Vietnam's power generation mix and it will rise to over 50% in 2030 if the coal-fired capacity is increased from 4,360 MW to 75,000 MW as planned. In this study we contrast the current CO 2 emissions from the existing sub-critical coal-fired plants in Vietnam, based on average operating efficiencies, with scenarios that assume the use of imported coal of varying grades instead of the use of domestic coal. We also explore how emissions could change with the adoption of supercritical- and ultra-supercritical combustion technologies. The results provide clear insights for policy-makers tasked with meeting Vietnam's future emissions standards. [ABSTRACT FROM AUTHOR]

Abstract: The Marine Strategy Framework Directive (MSFD) aims to achieve Good Environmental Status (GES) in Europe''s Seas. The requirement for regional sea authorities to identify and prioritise issues for management has meant that standardized methods to assess the current level of departure from GES are needed. The methodology presented here provides a means by which existing information describing the status of ecosystem components of a regional sea can be used to determine the effort required to achieve GES. A risk assessment framework was developed to score departure from GES for 10 out of the 11 GES descriptors, based on proposed definitions of ‘good’ status, and current knowledge of environmental status in each of the four regional seas (North-East Atlantic, Mediterranean Sea, Baltic Sea and Black Sea). This provides an approach for regional evaluation of environmental issues and national prioritisation of conservation objectives. Departure from GES definitions is described as ‘high’, ‘moderate’ or ‘low’ and the implications for management options and national policy decisions are discussed. While the criteria used in this study were developed specifically for application toward MSFD objectives, with modification the approach could be applied to evaluate other high-level social, economic or environmental objectives. [Copyright &y& Elsevier]

• A perturbational treatment of Coriolis interaction in the atom-diatom dimer is performed, taking the Ar-HCl complex as an example. • The study of rovibrational level structure is performed using coupled channel formulation. • The properties of a perturbation series are discussed; the results of perturbation analysis are compared with those from close-coupling calculations. The rovibrational levels for truly bound states were calculated for a weakly interacting dimer comprising an atom and a diatomic molecule. The off-diagonal Coriolis corrections were evaluated with perturbation theory. For the Ar - HCl dimer as a concrete example, the obtained results are compared with those from computer code BOUND [J. M. Hutson and C. R. Le Sueur. Comput. Phys. Commun., 241 , 1–8, (2019)]. [ABSTRACT FROM AUTHOR]

The N 2 − N 2 and N 2 − Ar continuum absorption spectra are calculated using the classical trajectory-based simulation (CTS). The spectra obtained are validated by new measurements in the subTHz spectral range along with the previously reported data in the far infrared. A novelty of our approach consists in the use of the CTS method to simulate both the fundamental nitrogen absorption band and the rototranslational band in N 2 − Ar , i.e., we succeeded to step beyond the conventionally used approximation of the only rigid monomers. This extension of the theory made it possible, in particular, to demonstrate the validity of the rigid monomer assumption for the CTS simulation of the rototranslational N 2 − Ar band. The broadband spectra within 77–354 GHz were measured using the resonator spectrometer at temperatures of 278–333 K and pressures of 900–1600 Torr. A minor underestimation of the calculated absorption by 3.7% and 5% is shown for the N 2 − N 2 and N 2 − Ar system, respectively. On the basis of the obtained data, a new analytical model is developed for the N 2 − N 2 absorption in the subTHz range, which can be used in radiation propagation codes for the Earth, Titan, or other nitrogen-rich atmospheres. The advantage of the model proposed here over those previously published is discussed. • Bimolecular spectra of N 2 N 2 and N 2 Ar are obtained using the classical trajectory-based simulation. • Theoretical spectra are validated by an extensive set of broad-band experimental spectra. • Proved deviation of the observed N 2 N 2 mm-wave continuum from quadratic dependence on frequency. • The fundamental N 2 CIA band in N 2 Ar is simulated beyond the rigid monomer approximation. • A new analytical model is developed for the N 2 N 2 continuum in the subTHz range. [ABSTRACT FROM AUTHOR]

Data collected during cruises of the Former Soviet Union (in 1963–1989) and the British Atlantic meridional transect program (in 1995–1999) were used to analyse macroscale patterns in phyto- and zooplankton biomass, size structure, species diversity, chlorophyll a, and plankton bioluminescence in the macroscale anticyclonic gyre of the South Atlantic Ocean. The spatial pattern of bioluminescence intensity was in good agreement with that of remotely sensed (CZCS) chlorophyll a, phosphate, salinity, and copepod species diversity index distributions especially in terms of geographic inclinations of the isolines, both associated with the north-westward pattern off the South equatorial current. Among the 416 copepod species recorded in samples, 51 species were noted throughout the whole gyre. On the other hand, there were a number of species found only in one of the currents. The mesozooplankton biomass size spectra (calculated in carbon units), exhibited a fairly stable slope of the curve from the eastern periphery of the gyre to its centre. The British Atlantic meridional transect program meridional transect through the western part of the gyre showed mesozooplankton size spectra in greater detail between the equator and 50° S. Although the spectra change slowly along the transect as far as 36° S, there is a general trend toward increasing slopes from the equatorial region to the oligotrophic central gyre. The calculated phyto-to-zooplankton ratio indicated that for the tropical anticyclonic gyres, the mesozooplankton carbon biomass could be represented as the exponential function of the phytoplankton carbon. [Copyright &y& Elsevier]

• The HITRAN2020 molecular spectroscopic database and its validations are presented. • Extended line-by-line coverage to 55 molecules, with new isotopologues included. • Increased spectral and dynamic ranges for multiple molecules. • Quality and amount of spectral parameters (including sophisticated line shapes) is increased. • Updates to cross sections, CIA, software tools & auxiliary data also described. The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. This paper describes the contents of the 2020 quadrennial edition of HITRAN. The HITRAN2020 edition takes advantage of recent experimental and theoretical data that were meticulously validated, in particular, against laboratory and atmospheric spectra. The new edition replaces the previous HITRAN edition of 2016 (including its updates during the intervening years). All five components of HITRAN have undergone major updates. In particular, the extent of the updates in the HITRAN2020 edition range from updating a few lines of specific molecules to complete replacements of the lists, and also the introduction of additional isotopologues and new (to HITRAN) molecules: SO, CH 3 F, GeH 4 , CS 2 , CH 3 I and NF 3. Many new vibrational bands were added, extending the spectral coverage and completeness of the line lists. Also, the accuracy of the parameters for major atmospheric absorbers has been increased substantially, often featuring sub-percent uncertainties. Broadening parameters associated with the ambient pressure of water vapor were introduced to HITRAN for the first time and are now available for several molecules. The HITRAN2020 edition continues to take advantage of the relational structure and efficient interface available at www.hitran.org and the HITRAN Application Programming Interface (HAPI). The functionality of both tools has been extended for the new edition. [ABSTRACT FROM AUTHOR]

• Measurements of the broad mm-wave continuum absorption of pure CO 2 and CO 2 -Ar mixtures. • Two independent semiclassical trajectory-based calculations of the absorption are compared to measurements. • Significant contribution from true bound dimers is revealed. • The formula describing both frequency and temperature dependence of the continuum is suggested for atmospheric applications. Broadband spectra of the continuum absorption in pure CO 2 gas and its mixture with Ar are studied at room temperature using a resonator spectrometer within 105–240 GHz. The expected pressure and frequency dependence is observed. The obtained data are validated by two independent calculations of the interaction-induced absorption using a semiclassical trajectory-based method. The observed continuum is interpreted in terms of bimolecular absorption, including a significant contribution from true bound dimers. A simplified formula describing both frequency and temperature dependency of the CO 2 –Ar continuum within a frequency range from 60 GHz to 450 GHz at temperatures from 200 K to 400 K is suggested for use in atmospheric studies. [ABSTRACT FROM AUTHOR]

• Nitrogen continuum spectrum is experimentally and theoretically studied under close to atmospheric conditions. • Obtained spectra validate previous experimental data and theoretical models. • We demonstrate negligible contribution of N 2 -N 2 bound dimer to the total absorption. • Refined set of empirical parameters is derived for the mm-submm radiation propagation models. We report the results of experimental study for the N 2 absorption in the millimeter wavelength range at pressure and temperature ranging, respectively, from 750 to 1500 Torr and from 265 to 310 K. The obtained data are shown to be in a good agreement with the previously published experimental results, as well as with the predictions issued from available empirical models of nonresonant absorption and from the simulation of the N 2 –N 2 rototranslational collision-induced absorption performed recently using the classical trajectories method relying on complete ab initio potential and induced dipole surfaces. Analysis of the first spectral moments leads to a conclusion that the role of true bound (N 2) 2 dimer absorption is negligible at least in the range of atmospheric temperatures. New experimental data reported in this paper are supported by our theoretical modelling being however somewhat in excess of the data presented in the HITRAN/CIA database for the same spectral range. We consider our data as an update of the previously available so-called "dry" atmospheric continuum which is conventionally employed nowadays in the mm-waves propagation models. [ABSTRACT FROM AUTHOR]