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[Display omitted] • Gd-modified Mn-Co LDOs derived from LDHs are developed for the SCR de-NO x. • Gd-modified Mn-Co LDOs exhibit excellent activity and high H 2 O/SO 2 tolerance. • The physicochemical properties inherited from LDHs and Gd-modification promote activity. • Both E-R and L-H mechanisms are included in SCR de-NO x over Gd-modified Mn-Co LDOs. Metal oxides derived from layered double hydroxides (LDHs) are expected to obtain low-temperature denitrification (de-NO x) catalysts with high catalytic activity and H 2 O/SO 2 tolerance in the selective catalytic reduction (SCR) of NO x with NH 3. In current work, we successfully prepared Gd-modified Mn-Co metal oxides derived from Gd-modified Mn-Co LDHs. The resultant Gd-modified Mn-Co metal oxides exhibit excellent catalytic activity and high H 2 O/SO 2 tolerance in the NH 3 -SCR de-NO x reaction. The reasons for the enhancement can be ascribed to the unique surface physicochemical properties inherited from LDHs and the modification of Gd, which increase the specific surface area, improve the relative content of Mn4+ and Co3+ on the surface, enhance the number of acidic sites, strengthen the reducibility of catalyst, resulting in the enhanced catalytic activity and H 2 O/SO 2 tolerance. Additionally, it is demonstrated that the NH 3 -SCR de-NO x reaction occurred on the surface of Gd-modified Mn-Co oxides followed both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms. This study provides us with a design approach to promote catalytic activity and H 2 O/SO 2 tolerance through morphology control and rare earth modification. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary heterostructure (ZnPPO) is constructed for photocatalytic H 2 evolution. • ZnPPO presents an enhanced photocatalytic H 2 evolution rate of 31.037 mmol h-1g−1. • A binding structure of Ⅱ-type and Z-scheme has been constructed in ZnPPO. • The binding structure promotes the transfer of photogenerated charge carriers. A ternary heterostructure (ZnPPO) was constructed by loading ZnO and tetrakis (4-carboxyphenyl) zinc porphyrin (ZnTCPP) with P-doped g-C 3 N 4 (PCN). In contrast to binary heterostructures (PCN-ZnO, ZnTCPP-ZnO and ZnTCPP-PCN) and single components (PCN, ZnTCPP and ZnO), ZnPPO has superior photocatalytic activity for H 2 generation from water splitting. It is revealed that a binding structure of Ⅱ-type and Z-scheme has been constructed in ZnPPO, which plays a vital role in transferring photo-excited charge carriers. The significant enhancement of photocatalytic activity in ZnPPO is attributed to the effective transfer of photo-generated electrons and holes between the components of the ternary heterostructure. [ABSTRACT FROM AUTHOR]

Attributing sources of tropical cyclogenesis (TCG) bias to large‐scale circulation in global circulation models is challenging. Here, we propose the use of empirical orthogonal functions as an approach to understand model bias of TCG. Two leading modes of large‐scale wind circulations in the West Pacific can explain the TCG frequency and location in both climate reanalysis and the MetUM model. In the reanalysis, the two modes distinguish the summer monsoon trough position and the strength of the north Pacific subtropical high. However, in the model, the wind circulations are biased toward the positive phase of simulated modes thus overestimating TCG in the entire Main Development Region. This bias is further related to the north‐eastward shifted monsoon trough and a weakened subtropical high, and overly strong tropics‐subtropics connections. This approach could be deployed more widely to other basins and models to diagnose the causes of TCG bias. Plain Language Summary: General Circulation Models (GCMs) have bias in tropical cyclogenesis (TCG). This bias largely reduces the credibility of GCMs. In this study, we suggest an empirical orthogonal function‐based approach to trace the sources of TCG bias in the western North Pacific more rigorously back to large‐scale wind circulation patterns. We find that TCG bias in both basin‐wide and regional scales is a combination of the two biased circulation patterns, associated with too strong tropics‐subtropics connections. The two biased circulation patterns are also featured with a north‐eastward shifted monsoon trough and a weakened subtropical high. We choose the Met Office climate models to demonstrate the approach. But, it can be applied to other GCMs and basins to better understand TCG bias and inform further model development. Key Points: Multivariate empirical orthogonal functions are used to diagnose model bias of tropical cyclogenesis (TCG) in the West PacificTwo leading modes of large‐scale wind circulations can explain most of TCG variability in both ECMWF fifth generation climate reanalysis and MetUMIn MetUM, positive TCG bias is related to large‐scale wind circulations biased toward the positive phase of the simulated modes [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn-based catalysts were successfully synthesized via a novel MOFs non-thermal derivation. • The Na 2 CO 3 concentration affected the formation of Mn-based catalysts. • Mn-Na-1.0 presented optimal catalytic activity and excellent water resistance. • The introduction of H 2 O enhanced toluene mineralization. The design of efficient catalysts with great water-resistance for volatile organic compounds (VOCs) degradation is challenging. Herein, series of Mn-based catalysts with great catalytic activity were prepared via a novel non-thermal derivation by Na 2 CO 3 solution treatment using Mn-MIL-100 as a sacrificial template. Among them, the Mn-Na-1.0 catalyst prepared by treating with 1.0 mol/L Na 2 CO 3 solution presented the optimal toluene degradation performance (T 90 = 209 °C) and water-resistance (5.0 vol%). Characterization results suggested that the abundant surface Mn3+ and O ads species, better surface lattice oxygen species mobility, low-temperature reducibility, and high surface area accounted for the great catalytic performance of the Mn-Na-1.0 catalyst. Importantly, the promotion of water vapor to toluene oxidation was observed and systematically elucidated by many characterizations and experiments. The results showed that the introduced water vapor was activated and dissociated to form dissociation adsorbed active oxygen species, which served as the additional active site and provided active oxygen species to accelerate the oxidation of intermediates and toluene mineralization. This work provided a novel approach for designing Mn-based catalysts with good water-resistance in VOCs degradation under actual industrial conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene-based aerogels used for environmental pollutant removal are classified. • The applications of in pollution removal are summarized. • The challenges and opportunities of using graphene-based aerogels are prospected. • Graphene-based aerogels are promising 3D environmental functional materials. Graphene-based aerogels have attracted considerable interest in recent years for their ability to remove toxic pollutants, due to their attractive properties, which include a sufficient number of anchor positioning points, arbitrarily changing shapes, and adjustable functional groups and pore sizes. The potential methods for adsorption, degradation, and reduction of water and atmospheric pollutants using graphene-based aerogels have been thoroughly investigated. Firstly, this review introduced the current research on the application of graphene-based aerogels as environmentally efficient materials for removing water and atmospheric contaminants, including heavy metal ions, organic dyes, nitrogen oxides (NO x), and volatile organic compounds (VOCs). Secondly, the important role in promoting adsorption and catalysis and the types of modifications of graphene aerogels are discussed in depth. Finally, this review summarized the great potential of graphene-based aerogels as environmentally functional materials and put forward the challenges and prospects, aiming to promote the development and industrial application of graphene-based aerogels. [ABSTRACT FROM AUTHOR]

The performance of the Met Office Global Seasonal Forecast System (GloSea5-GC2) for tropical cyclone (TC) frequency for the western North Pacific (WNP) in July–October is evaluated, using 23 years of ensemble forecasts (1993–2015). Compared to observations, GloSea5 overpredicts the climatological TC frequency in the eastern WNP and underpredicts it in the western and northern WNP. These biases are associated with an El Niño–type bias in TC-related environmental conditions (e.g., low-level convergence and steering flow), which encourages too many TCs to form throughout the tropical Pacific and slows TC propagation speed. For interannual TC frequency variability, GloSea5 overestimates the observed negative TC–ENSO teleconnection in the western and northern WNP, associated with an eastward shift in the ENSO teleconnection to environmental conditions. Consequently, GloSea5 fails to predict interannual TC variability in the northeast WNP (south of Japan); performance is higher in the southwest WNP (e.g., the South China Sea) where the sign of the TC–ENSO teleconnection is correct. This study suggests the need to reduce biases in environmental conditions and associated ENSO teleconnections in GloSea5 to improve the TC prediction performance in the NWP. [ABSTRACT FROM AUTHOR]

The European Centre for Medium-range Weather Forecasts (ECMWF) has produced the ocean-atmosphere coupled reanalysis for the twentieth century, CERA-20C, following on from the similar but atmosphere-only reanalysis ERA-20C. Here we demonstrate the capability of CERA-20C in producing more physically consistent ocean and atmosphere boundary conditions, by focusing on sea surface temperature (SST)-precipitation intraseasonal relationships. CERA-20C reproduces well the observed SST-precipitation correlations, while these relationships are poorly represented in ERA-20C, with the greatest discrepancies in the early 1900s. The improved relationships in CERA-20C are due to intraseasonal improvements in SST that are not present in the external HadISST2 product. In CERA-20C, SST-precipitation relationships are slightly weaker in the 1900s than in the 2000s, mainly due to differences in the assimilated observation density. We also find that the coupled model initialized from CERA-20C in the 2000s realistically simulates these relationships, while relaxing SST toward HadISST2 tends to damp these relationships. CERA-20C has improved mean and variance in precipitation over ERA-20C, but these are mostly due to improvements in the atmospheric model and not due to coupled feedbacks. [ABSTRACT FROM AUTHOR]

Feng, X., Shaw, A.G.P. and Zhang, W., 2013. Study on reverse calculation for unidirectional waves from shallow water In the coastal region, some wave measurements are usually deployed in shallow water. However, the knowledge of deep-water waves is more required in some cases. Targeting the east coast of Taiwan with a steep slope, we experimentally detect the capability of the linear spectrum theory in reversely estimating unidirectional deep-water waves from the shallow-water waves. Tank experiments of irregular waves show that the nonlinearity of wave-wave interactions significantly contributes to the total energy transfer. The energy of incident waves around peak frequency is transferred to lower and higher frequency domains. Even though waves are travelling through a short distance under a steep slope, the nonlinear wave-wave interactions cannot be neglected. In the application of the linear spectrum theory, the reversely calculated deep-water spectrum is found to be overestimated in frequency over 2Hz and in total energy of spectrum, but underestimated around peak frequency. There is evidence to show that the ratio of H1/3/Hs is correlated with the spectral bandwidth and Kurtosis. [ABSTRACT FROM AUTHOR]

• Yolk-shell-like CoCrO x with mesoporous structure has molecule enrichment ability. • The generation of Cr6+ and oxygen species benefits to dichloromethane destruction. • Surface lattice oxygen species are crucial for dichloromethane destruction. • The generation and cleavage of C H/CC l bonds cause the formation of by-products. • Acid species can effectively inhibit the formation of polychlorinated by-products. Promoting chlorine resistance and inhibiting by-product generation are critical issues in catalytic destruction of chlorinated volatile organic compounds (CVOCs). Herein, a yolk-shell-like mesoporous CoCrO x as a robust catalyst was synthesized for deep destruction of dichloromethane (DCM) considering its superior mass transfer and molecule enrichment ability. The strong interaction between Co and Cr elements in CoCrO x results in efficient generation of active Cr6+ and oxygen species, which greatly enhances the activity of CoCrO x in DCM oxidation, much higher than that of Co 3 O 4 , Co 3 O 4 +Cr 2 O 3 and Cr 2 O 3. Chloromethane (CH 3 Cl), trichloromethane (CHCl 3) and tetrachloromethane (CCl 4) can be detected as the cleavage of C H bond and generation of C-Cl bond during DCM destruction. We found that the acid sites can effectively inhibit the formation of by-products over CoCrO x material, which is a promising material for CVOC elimination. The results from this work provide some new insights into the design of catalysts for CVOC destruction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Defects were introduced in MIL-125 to narrow the forbidden band width. • Improved the surface acidity of material for efficient degradation of mixed VOCs. • Revealed the catalytic mechanism using in situ DRIFTS spectroscopy and GC–MS. In this paper, the effect of three monocarboxylic acids on MIL-125 synthesis was systematically investigated and the results were discussed in detail. X-ray diffractometry (XRD) and nitrogen adsorption–desorption curves indicated that small molecule acids (acetic acid, propionic acid and butyric acid) affected the morphology of MIL-125 and induced lamellar pores and structural defects in the crystals. Thermogravimetric measurements confirmed the presence of acid-regulated defective metal–organic frameworks (MOFs). Electrochemical tests and density function theory calculations indicated that acid modulation could change the forbidden bandwidth of the material. The acid modification strategy effectively promoted the transfer of photogenerated electrons and enhanced the adsorption and activation of O 2 and H 2 O molecules, generating reactive radicals. The modified MOFs also showed excellent performance in the removal of mixed toluene and chlorobenzene. The degradation pathways of the mixture were analyzed by in situ infrared (IR) and gas chromatography-mass spectrometry (GC–MS). The mixture was converted to chlorophenolic intermediates in the presence of reactive oxygen species, further decomposed to form ethers and ethanol, and finally formed small molecules such as carbon dioxide and water. A feasible method was provided for the preparation of photocatalysts for the treatment of mixed VOCs. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) seriously threaten the safety of human life and property especially when approaching a coast or making landfall. Robust, long-lead predictions are valuable for managing policy responses. However, despite decades of efforts, seasonal prediction of TCs remains a challenge. Here, we introduce a deep-learning prediction model to make skillful seasonal prediction of TC track density in the Western North Pacific (WNP) during the typhoon season, with a lead time of up to four months. To overcome the limited availability of observational data, we use TC tracks from CMIP5 and CMIP6 climate models as the training data, followed by a transfer-learning method to train a fully convolutional neural network named SeaUnet. Through the deep-learning process (i.e., heat map analysis), SeaUnet identifies physically based precursors. We show that SeaUnet has a good performance for typhoon distribution, outperforming state-of-the-art dynamic systems. The success of SeaUnet indicates its potential for operational use. [ABSTRACT FROM AUTHOR]

In this study, we examined the sensitivity of tropical cyclone (TC) characteristics and precipitation to the Cordillera Mountain Range (CMR) in Luzon, Philippines. Using the Weather Research and Forecasting (WRF) model, we simulated eight TCs with four different CMR orographic elevations: Control, Flat, Reduced, and Enhanced. We found that at significance level α = 0.05 , TC intensity significantly weakened as early as 21 h prior to landfall in the Enhanced experiment relative to the Control, whereas there was little change in the Flat and Reduced experiments. However, throughout the period when the TC crossed Luzon, we found no significant differences for TC movement speed and position in the different orographic elevations. When a TC made landfall, associated precipitation over the CMR increased as the mountain height increased. We further investigated the underpinning processes relevant to the effect of the CMR on precipitation by examining the effects of mountain slope, incoming perpendicular wind speed, and the moist Froude Number ( F w ). Compared with other factors, TC precipitation was most strongly correlated with the strength of approaching winds multiplied by the mountain slope, i.e., stronger winds blowing up steeper mountain slopes caused higher amounts of precipitation. We also found that individually, F w , mountain height, and upslope wind speeds were poor indicators of orographically induced precipitation. The effects of mountain range on TC rainfall varied with TC cases, highlighting the complexity of the mountain, wind, and rainfall relationship. [ABSTRACT FROM AUTHOR]

A new regional coupled modelling framework is introduced – the Regional Coupled Suite (RCS). This provides a flexible research capability with which to study the interactions between atmosphere, land, ocean, and wave processes resolved at kilometre scale, and the effect of environmental feedbacks on the evolution and impacts of multi-hazard weather events. A configuration of the RCS focussed on the Indian region, termed RCS-IND1, is introduced. RCS-IND1 includes a regional configuration of the Unified Model (UM) atmosphere, directly coupled to the JULES land surface model, on a grid with horizontal spacing of 4.4 km, enabling convection to be explicitly simulated. These are coupled through OASIS3-MCT libraries to 2.2 km grid NEMO ocean and WAVEWATCH III wave model configurations. To examine a potential approach to reduce computation cost and simplify ocean initialization, the RCS includes an alternative approach to couple the atmosphere to a lower resolution Multi-Column K-Profile Parameterization (KPP) for the ocean. Through development of a flexible modelling framework, a variety of fully and partially coupled experiments can be defined, along with traceable uncoupled simulations and options to use external input forcing in place of missing coupled components. This offers a wide scope to researchers designing sensitivity and case study assessments. Case study results are presented and assessed to demonstrate the application of RCS-IND1 to simulate two tropical cyclone cases which developed in the Bay of Bengal, namely Titli in October 2018 and Fani in April 2019. Results show realistic cyclone simulations, and that coupling can improve the cyclone track and produces more realistic intensification than uncoupled simulations for Titli but prevents sufficient intensification for Fani. Atmosphere-only UM regional simulations omit the influence of frictional heating on the boundary layer to prevent cyclone over-intensification. However, it is shown that this term can improve coupled simulations, enabling a more rigorous treatment of the near-surface energy budget to be represented. For these cases, a 1D mixed layer scheme shows similar first-order SST cooling and feedback on the cyclones to a 3D ocean. Nevertheless, the 3D ocean generally shows stronger localized cooling than the 1D ocean. Coupling with the waves has limited feedback on the atmosphere for these cases. Priorities for future model development are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] The flame temperature was significantly affected by heat input at lower flame speed. [•] The flame temperature was affected by heat loss at higher flame velocity. [•] The flame temperature of foams was lower than that of packed beads and honeycombs. [•] The CO emission was mainly determined by the flame temperature. [•] The HC emission was mainly controlled by the mixing uniformity of fuel/air. [Copyright &y& Elsevier]

A new regional coupled modelling framework is introduced - the Regional Coupled Suite (RCS). This provides a flexible research capability with which to study the interactions between atmosphere, land, ocean and wave processes resolved at km-scale, and the effect of environmental feedbacks on the evolution and impacts of multi-hazard weather events. A configuration of the RCS focussed on the Indian region, termed RCS-IND1, is introduced. RCS-IND1 includes a regional configuration of the Unified Model (UM) atmosphere, directly coupled to the JULES land surface model, on a grid with horizontal spacing of 4.4 km, enabling convection to be explicitly simulated. These are coupled through OASIS3-MCT libraries to 2.2 km grid NEMO ocean and WAVEWATCH III wave model configurations. To examine a potential approach to reduce computation cost, and simplify ocean initialisation, the RCS includes an alternative approach to couple the atmosphere to a lower resolution Multi-Column K Profile Parameterization (KPP) for the ocean. Through development of a flexible modelling framework, a variety of fully and partially coupled experiments can be defined, along with traceable uncoupled simulations and options to use external input forcing in place of missing coupled components. This offers a wide scope to researchers designing sensitivity and case study assessments. Case study results are presented and assessed to demonstrate the application of RCS-IND1 to simulate two tropical cyclone cases which developed in the Bay of Bengal, namely Titli in October 2018 and Fani in April 2019. Results show realistic cyclone simulations, and that coupling can improve the cyclone track and produces more realistic intensification than uncoupled simulations for Titli but prevents sufficient intensification for Fani. Atmosphere-only UM regional simulations omit the influence of frictional heating on the boundary layer to prevent cyclone over-intensification. However, it is shown that this term can improve coupled simulations, enabling a more rigorous treatment of the near-surface energy budget to be represented. For these cases, a 1D mixed layer scheme shows similar first-order SST cooling and feedback on the cyclones as a 3D ocean. Nevertheless, the 3D ocean generally shows stronger localised cooling than the 1D ocean. Coupling with the waves have limited feedback on the atmosphere for these cases. Priorities for future model development are discussed. [ABSTRACT FROM AUTHOR]

• The stabilization mechanism of single atom Pt 1 -CeO 2 materials was proposed. • The Pt-O-Ce interface distortion balanced the Fermi energy level and charge density. • The interface distortion promoted the adsorption capacity of O 2 and methanol. • The Pt 1 -CeO 2 {100} catalyst exhibits outstanding catalytic efficiency and stability. • The methanol oxidation and surface reconstruction were revealed in an atomic-scale. Exploring thermally robust single atom catalysts (SACs) is of great significance. Here, we develop a universal strategy for stabilizing Pt atoms on the mono-oxygen vacancies of CeO 2 with diverse exposed facets. The stabilization mechanism was proposed that the formed Pt-O-Ce interface will be taken into distortion spontaneously to keep thermodynamics stable through strong metal-support interactions. The highest degree of Pt-O-Ce distortion is achieved over Pt1-CeO2{100} material, which exhibits exceptional efficiency and thermal stability for oxygenated hydrocarbon removal. The enhanced adsorption capacity of O2 and methanol confirmed in the distortion interface is seen as another crucial reason for improving the stability of SACs. Methanol oxidation on Pt1-CeO2{100} obeys the L-H mechanism under relatively low temperature and then goes through to the MVK mechanism with temperature increasing. We believe that these results would bring new opportunities in the fabrication of SACs and applications of them in thermal reactions. [ABSTRACT FROM AUTHOR]

The European Reanalysis of Global Climate Observations 2 (ERA-CLIM2) is a European Union Seventh Framework Project started in January 2014 and due to be completed in December 2017. It aims to produce coupled reanalyses, which are physically consistent datasets describing the evolution of the global atmosphere, ocean, land surface, cryosphere, and the carbon cycle. ERA-CLIM2 has contributed to advancing the capacity for producing state-of-the-art climate reanalyses that extend back to the early twentieth century. ERA-CLIM2 has led to the generation of the first European ensemble of coupled ocean, sea ice, land, and atmosphere reanalyses of the twentieth century. The project has funded work to rescue and prepare observations and to advance the data-assimilation systems required to generate operational reanalyses, such as the ones planned by the European Union Copernicus Climate Change Service. This paper summarizes the main goals of the project, discusses some of its main areas of activities, and presents some of its key results. [ABSTRACT FROM AUTHOR]