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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]

This study presents an analysis of the equatorial waves in the ERA5 reanalysis and forecasts of the Met Office Global Seasonal Forecast System version 5 (GloSea5), by projecting dynamical fields onto theoretical equatorial wave modes. The seasonal and interannual variation of equatorial wave activity in GloSea5 is evaluated against ERA5 waves. We find that in ERA5 the seasonal and spatial variations of eastward‐moving Kelvin wave activity are mainly determined by the ambient zonal flow, with wave activity being stronger in easterlies than westerlies. For the westward‐moving mixed Rossby–gravity waves and equatorial Rossby waves, the seasonal and spatial variations of the upper‐tropospheric wave activity are determined by both the ambient flow and extratropical forcing with stronger wave activity generally in the westerlies, whilst the lower‐tropospheric wave activity is related to the ambient flow and tropical convection. In GloSea5, the Kelvin wave activity is not well simulated in the upper troposphere, and in general the wave activity and wave‐related convective signal are too weak. In contrast, GloSea5 performs better for the westward‐moving equatorial waves, including their Doppler‐shifted eastward‐moving components, despite a significant overestimation in the Atlantic and African region. The phase of ENSO has a substantial impact on equatorial waves in both ERA5 and GloSea5. The mechanism of the impact is through changes in the ENSO‐related ambient flow, upper‐tropospheric extratropical forcing, and tropical convection. GloSea5 can capture the low‐level Kelvin wave–ENSO relationship reasonably well, with stronger wave activity over the eastern Pacific in El Niño, although the ENSO‐driven variation is too weak. The wave–ENSO relationship for westward‐moving waves is well represented in GloSea5, especially in the upper‐level eastern‐Pacific westerly duct region in the extended boreal winter and the low‐level Indo‐Pacific in all seasons. We conclude that in GloSea5 the representation of the wave–ENSO teleconnection is the key driver for the performance of interannual variability in the wave activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn-Co LDOs derived from Mn-Co LDHs are developed for the SCR de-NO x. • Mn-Co LDOs present excellent catalytic activity and SO 2 tolerance in SCR de-NO x reaction. • The special physicochemical properties endowed by its LDO structure enhance activity. • The enhanced SO 2 tolerance is due to the weak adsorption energy of SO 2 on Mn-Co LDO. • Both E-R and L-H mechanisms are included in the NH 3 -SCR de-NO x over the Mn-Co LDOs. Mn-based catalysts have a fatal flaw in selective catalytic reduction (SCR) of NO x with NH 3 , which is poor SO 2 tolerance. In this work, we successfully fabricated Mn-Co layered double oxides (LDOs) by calcining the Mn-Co layered double hydroxides (LDHs) generated by a hydrothermal method using urea solution. The obtained Mn-Co LDO presents excellent catalytic activity and SO 2 tolerance in the SCR reaction of NO x with NH 3. The enhanced activity can be attributed to the special surface physicochemical properties endowed by its LDO structure, such as large specific surface area, more exposed active sites, relatively high Mn4+ and O α /(O α + O β) percentage, good reducibility, and abundant acidic sites. The enhanced SO 2 tolerance can be ascribed to the weak adsorption energy of SO 2 on Mn-Co LDO, which makes it difficult for SO 2 to interact with the active sites. Furthermore, the NH 3 -SCR of NO x reaction that occurs on the surface of the MnCo-LDO follows both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms. This study shines light on the design of Mn-based de-NO x catalysts with excellent SO 2 tolerance. [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]

Understanding water level (WL) fluctuations in river deltas is important for managing water resources and minimizing the impacts of floods and droughts. Here, we demonstrate the competing effects of atmospheric and oceanic forcing on multi-time-scale variability and changes in the Pearl River Delta (PRD) WLs in southern China, using 52 years (1961–2012) of in situ observations at 13 hydrological stations. PRD WL presents significant seasonal to decadal variations, with large amplitudes upstream related to strong variability of southern China rainfall, and with relatively small amplitudes at the coastal stations determined by sea level (SL) fluctuations of the northern South China Sea. We find that the strengths of atmospheric and oceanic forcing in PRD are not mutually independent, leading to a distinct contrast of WL–forcing relationships at upstream and coastal stations. In the transition zone, because of the counteraction of atmospheric and oceanic forcing, no robust relationships are identified between WL and either of the forcing. We further show that in the drought season of the warm ENSO and PDO epochs, the effect of atmospheric (oceanic) forcing on PRD WL is largely enhanced (weakened), due to increased southern China rainfall and negative SL anomalies. Over the observation period, WL significantly decreased at upstream stations, by up to 28–42 mm yr−1 for flood season, contrasting with the upward trends of <4.3 mm yr−1 at coastal stations across all seasons. Southern China rainfall explains little of the observed WL trends, while SL rise is mostly responsible for the WL trends at coastal stations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn y Co 3−y O x is prepared by an ultrasonic technology followed by a hydrothermal treatment. • Mn y Co 3−y O x catalyst exhibits significantly enhanced low-temperature de-NO x performance. • The interaction between MnO x and CoO x improves the de-NO x performance of Mn y Co 3−y O x. • Both E-R and L-H mechanisms are included in the NH 3 -SCR de-NO x over the Mn y Co 3−y O x. NO x emission is a major environmental issue. Selective catalytic reduction (SCR) is the most effective method for the conversion of NO x in flue gases to harmless N 2 and H 2 O. In this work, a series of Mn-Co mixed metal oxides, Mn y Co 3−y O x , are intentionally prepared by an ultrasonic technology followed by a hydrothermal treatment, and their denitration (de-NO x) performances are evaluated by the SCR reaction in the presence of NH 3. The results show that the SCR de-NO x performance of Mn y Co 3−y O x is significantly improved compared with single metal oxide (MnO x or CoO x). The reason can be ascribed to a strong interaction between MnO x and CoO x , which reduces the crystallinity of Mn y Co 3−y O x catalysts, increases the specific surface area, builds the redox cycle of Co3+ + Mn3+ ↔ Co2+ + Mn4+, improves the reducibility, enhances the surface acid sites, accelerates the reaction between the adsorbed NO x species and the coordinated NH 3 bound to the Lewis acid site, resulting in a significant improvement in the SCR de-NO x performance. The work provides us with a thought to improve the de-NO x performance by building a strong interaction between catalyst components. [ABSTRACT FROM AUTHOR]

[Display omitted] • CdS@ZnO core–shell NRAs is constructed by ALD for H 2 evolution from PEC water splitting. • CdS@ZnO 200 presents an enhanced PEC H 2 evolution rate of 21.64 μmol·h−1·cm−2. • Z-scheme mechanism between CdS and ZnO promotes the separation of electrons and holes. • The close contact between two semiconductors reduces transfer resistance of charge carriers. • ZnO shell tightly wraps CdS core to prevent its photo-corrosion. Photoelectrochemical (PEC) water splitting provides a promising strategy for the production of clean hydrogen fuel. Herein, a new CdS@ZnO core–shell nanorod arrays (NRAs) is successfully constructed by atomic layer deposition (ALD) for H 2 evolution from PEC water splitting. The CdS@ZnO 200 obtained after 200 ALD cycles presents a significantly enhanced PEC H 2 evolution rate of 21.64 μmol·h−1·cm−2, which is about 9.4 times of pristine CdS NRAs (2.31 μmol·h−1·cm−2). The reasons for the improved PEC H 2 evolution performance can be ascribed to several aspects: firstly, the Z-scheme charge transfer mechanism formed between CdS core and ZnO shell promotes the effective spatial separation of photo-induced electrons and holes; secondly, the close contact between the two semiconductors resulted from ALD process helps to reduce the transfer resistance of charge carriers. In addition, the CdS core is tightly wrapped by ZnO shell, which helps to prevent the photo-corrosion of CdS core. This work provides a new type of photoanode material suitable for PEC H 2 evolution from water splitting, and provides an efficient anti-corrosion method for the use of photocorrosive semiconductor materials. [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]

We examine the merit of atmosphere–ocean coupled models for tropical cyclone (TC) predictions in the western North Pacific (WNP), where accurate TC predictions remain challenging. The UK Met Office operational atmospheric global numerical weather prediction (NWP) model is compared with two trial coupled configurations, in which the operational atmospheric model is coupled to a one‐dimensional mixed‐layer ocean model and a three‐dimensional dynamical ocean model. Reforecasts for the 2016 TC season show that the coupled models outperform the NWP model for TC location predictions, with a systematic improvement of 50–100 km over the seven‐day forecasts, but the coupled models amplify the underestimation of TC intensity in the NWP model. Nearly identical TC predictions (for both location and intensity) are found in the two coupled models, indicating the dominance of thermodynamic processes at the air–sea interface for TC predictions on these timescales. The improved prediction of the TC position in the coupled models is associated with an enhanced Western North Pacific Subtropical High (WNPSH), which introduces an anticyclonic steering flow anomaly that shifts TC tracks further west in the southern part of the region and further east in the northern part. Based on sensitivity experiments, we show that these improvements in the coupled models are due mainly to colder initial sea‐surface temperatures (SSTs). Air–sea feedbacks do not change the WNPSH or TC tracks noticeably. Apart from the effect of the initial SSTs, tropical ocean warming due to air–sea interaction in the coupled forecasts can also reduce the predicted TC intensity, presumably due to a stronger regional Hadley circulation with increased subtropical subsidence. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ce modified Cu-SSZ-13 molecular sieves are prepared by the ion exchange method. • The de-NO x performance and hydrothermal stability of Ce/Cu-SSZ-13 are enhanced. • The modification of Ce promotes the migration of Cu2+ to a more stable six membered ring. • The reaction mechanisms over the Ce/Cu-SSZ-13 are fully revealed by in-situ DRIFTS. With the increase of car ownership, new challenges are posed to the treatment of mobile source exhaust gas, especially denitration (de-NO x). It is urgent to develop highly efficient de-NO x catalyst with a wide working temperature window. In this work, a series of Ce modified Cu-SSZ-13 molecular sieves (Ce/Cu-SSZ-13) are prepared by ion exchange method with different exchange times (x = 1, 2, 4, 8 h), and the role of Ce in promoting low-temperature de-NO x performance and hydrothermal stability of Ce/Cu-SSZ-13 in the selective catalytic reduction (SCR) of NO x are investigated. Both the low-temperature de-NO x performance and the hydrothermal stability of Cu-SSZ-13 are enhanced due to the modification of Ce, especially the Ce/Cu-SSZ-13 with an exchange time of 2 h. Both Ce/Cu-SSZ-13 and Cu-SSZ-13 present more than 95 % NO x conversion in the temperature region of 210–600 °C, and Ce modification significantly improves the NO x conversion in the low-temperature range (120–210 °C). It is revealed that the acidity, the surface Cu2+/Cu+ ratio and the NH 3 adsorption amount on Cu-SSZ-13 increase after Ce ion exchange, and the active component Cu2+ migrates to the more stable six-membered ring due to the modification of Ce, all of which have promote the improvement of NH 3 -SCR de-NO x performance. Furthermore, in the process of hydrothermal aging, the presence of Ce protects the framework of Cu-SSZ-13, acidic sites and active component Cu2+, which greatly improves the hydrothermal stability of Cu-SSZ-13 molecular sieve. In addition, in-situ DRIFTS shows that the developed Ce/Cu-SSZ-13 follows dual mechanisms of Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) to undergo NH 3 -SCR reaction. This work provides a new idea for improving the low-temperature de-NO x performance and hydrothermal stability of Cu-SSZ-13. [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]

There are no well-accepted mechanisms that can explain the annual frequency of tropical cyclones (TCs) both globally and in individual ocean basins. Recent studies using idealized models showed that the climatological frequency of TC genesis (TCG) is proportional to the Coriolis parameter associated with the intertropical convergence zone (ITCZ) position. In this study, we investigate the effect of the ITCZ position on TCG on the interannual time scale using observations over 1979–2020. Our results show that the TCG frequency is significantly correlated with the ITCZ position in the North Atlantic (NA) and western North Pacific (WNP), with more TCG events in years when the ITCZ is farther poleward. The ITCZ–TCG relationship in NA is dominated by TCG events in the tropics (0°–20°N), while the relationship in WNP is due to TCs formed in the east sector (140°E–180°). We further confirmed that ENSO has little effect on the ITCZ–TCG relationship despite the fact that it can affect the ITCZ position and TCG frequency separately. In NA and WNP, a poleward shift of ITCZ is significantly associated with large-scale environment changes favoring TCG in the main development region (MDR). However, the basinwide TCG frequency has a weak relationship with the ITCZ in other ocean basins. We showed that a poleward ITCZ in the eastern North Pacific and South Pacific favors TCG on the poleward flank of the MDR, while it suppresses TCG on the equatorward flank, leading to insignificant change in the basinwide TCG frequency. In the south Indian Ocean, the ITCZ position has weak effect on TCG frequency due to the mixed influences of environmental conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Mn-Ce@Na-Al 2 O 3 @Al mesh monolithic catalysts were facilely prepared. • Appropriate Ce doping can obviously enhance the toluene oxidation efficiency. • Ce species promotes the adsorption of oxygen and toluene molecules. • Oxygen vacancies can form easier on Ce modified monolithic catalysts. • Benzoate species oxidation was the rate determining step in toluene destruction. Here, a series of Mn-Ce binary oxides loaded monolith catalysts, with the support consisting of Na-Al 2 O 3 grown on Al mesh obtained by steam vapor treating, were prepared to attain efficient toluene destruction. On increasing CeO 2 loading, the toluene conversion over prepared catalysts shows an exponential rise, with Mn-4Ce@Na-Al 2 O 3 @Al monolithic catalyst exhibiting the optimal performance, over which 90% of toluene can be decomposed at 239 °C with oxidation rate over 5.57 × 10−7 mol·g−1·s−1, obviously higher than those over 4Ce/Na-Al 2 O 3 @Al (239 °C; 0.99 × 10−7 mol·g−1·s−1) and Mn/Na-Al 2 O 3 @Al (291 °C; 4.12 × 10−7 mol·g−1·s−1). H 2 -TPR and XPS results reveal that the superior redox ability and the formation of MnCeO x solid solution are favorable for toluene abatement. Oxygen vacancies form easily on the surface of Ce modified samples, resulting in superior oxygen and toluene adsorption ability, as demonstrated by DFT theoretical calculation. Besides, the pathways of toluene oxidation over Mn-4Ce@Na-Al 2 O 3 @Al catalyst were identified by using the in situ DRIFTS, and the key intermediates of toluene oxidation reaction are determined to be benzoyl, benzaldehyde, and benzoate. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyses 10years of in-situ measurements of significant wave height (Hs ) and maximum wave height (H max) from the ocean weather ship Polarfront in the Norwegian Sea. The 30-minute Ship-Borne Wave Recorder measurements of H max and Hs are shown to be consistent with theoretical wave distributions. The linear regression between H max and Hs has a slope of 1.53. Neither Hs nor H max show a significant trend in the period 2000–2009. These data are combined with earlier observations. The long-term trend over the period 1980–2009 in annual Hs is 2.72±0.88cm/year. Mean Hs and H max are both correlated with the North Atlantic Oscillation (NAO) index during winter. The correlation with the NAO index is highest for the more frequently encountered (75th percentile) wave heights. The wave field variability associated with the NAO index is reconstructed using a 500-year NAO index record. Hs and H max are found to vary by up to 1.42m and 3.10m respectively over the 500-year period. Trends in all 30-year segments of the reconstructed wave field are lower than the trend in the observations during 1980–2009. The NAO index does not change significantly in 21st century projections from CMIP5 climate models under scenario RCP85, and thus no NAO-related changes are expected in the mean and extreme wave fields of the Norwegian Sea. [Copyright &y& Elsevier]

Abstract: Large waves pose risks to ships, offshore structures, coastal infrastructure and ecosystems. This paper analyses 10 years of in-situ measurements of significant wave height (H s ) and maximum wave height (H max ) from the ocean weather ship Polarfront in the Norwegian Sea. During the period 2000 to 2009, surface elevation was recorded every 0.59s during sampling periods of 30min. The H max observations scale linearly with H s on average. A widely-used empirical Weibull distribution is found to estimate average values of H max /H s and H max better than a Rayleigh distribution, but tends to underestimate both for all but the smallest waves. In this paper we propose a modified Rayleigh distribution which compensates for the heterogeneity of the observed dataset: the distribution is fitted to the whole dataset and improves the estimate of the largest waves. Over the 10-year period, the Weibull distribution approximates the observed H s and H max well, and an exponential function can be used to predict the probability distribution function of the ratio H max /H s . However, the Weibull distribution tends to underestimate the occurrence of extremely large values of H s and H max . The persistence of H s and H max in winter is also examined. Wave fields with H s >12m and H max >16m do not last longer than 3h. Low-to-moderate wave heights that persist for more than 12h dominate the relationship of the wave field with the winter NAO index over 2000–2009. In contrast, the inter-annual variability of wave fields with H s >5.5m or H max >8.5m and wave fields persisting over ~2.5 days is not associated with the winter NAO index. [Copyright &y& Elsevier]

Chemical looping CO 2 splitting is a novel technology to coproduce syngas and pure CO. Herein, a series of x NiO/(CeO 2 -MgO) (x = 0, 1, 5, 7, 10 and 15 wt%) oxygen carriers were prepared by a co-precipitation method. The physicochemical characterizations suggest that the addition of NiO into the CeO 2 -MgO oxygen carrier significantly enhances the activity for the CH 4 and CO 2 conversion. In particular, the addition of 10 wt% NiO increases the CH 4 conversion from 15.62% to 59.64% with a CO selectivity of nearly 100% in multiple redox tests at 800 °C. The produced syngas also maintains a stable H 2 /CO molar ratio of 2.0 during the CH 4 reduction step. The oxygen exchange between oxygen carriers and CO 2 becomes easier, which enhances the yields of CO up to 1.75 mmol/g in the CO 2 splitting step. The formation of CeO 2 -NiO and NiO-MgO double solid solutions is found in the oxygen carriers, which avoids the agglomeration of NiO and improves the redox stability of the oxygen carrier. In addition, some Ni species in solid solutions migrate from the bulk to the surface after redox cycles, which contributes to the greater contact opportunity with the reacting gas to promote the CH 4 conversion and CO 2 activation. • A series of x NiO/CeO 2 -MgO oxygen carrier was prepared for CLCS. • The addition of NiO on CeO 2 -MgO strongly improves the methane conversion rate and keeps good redox stability of the OCs. • The part nickel in Ni Ce and Ni Mg solid solution can be reduced by CH 4. [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]

[Display omitted] • Birnessite-type short rod-like MnO 2 (MnO 2 -SR) was prepared under ambient conditions. • MnO 2 -SR exhibits the highest activity with 90% of propane oxidized at 225 °C. • Oxygen vacancies and high valent Mn4+ species promote activating of O 2 and propane. • Dissociation of propane molecules is the decisive step in propane oxidation. Developing economical and robust noble metal-free materials for obstinate light alkane low-temperature decomposition is of great significance. Here, birnessite-type short rod-like MnO 2 was firstly prepared by facile mixing KMnO 4 and ascorbic acid under ambient conditions and employed in propane catalytic decomposition. Experimental results revealed that abundant oxygen vacancies and high valent Mn4+ species, superior reducibility, and high surface oxygen mobility guarantee the remarkable low-temperature activity of MnO 2 -SR, over which 90% of propane can be oxidized (T 90) at temperature as low as 225 °C, achieving a temperature reduction over 70 °C compared with that of δ-MnO 2 (T 90 = 300 °C) and α-MnO 2 (T 90 = 355 °C). In situ diffuse reflectance infrared Fourier transform spectroscopy revealed that the dissociation and activation of propane molecules is the decisive step in propane oxidation. Gaseous propane is slowly oxidized by adsorbed oxygen directly to the final mineralization products at low temperature region (<200 °C); at high temperature region (>200 °C) however, propane molecules are firstly dissociated and activated before oxidized to carbonate intermediate products over active oxygen, and then eventually oxidized to carbon dioxide and water. [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]

• Porous MnCoNiO x trimetallic spinel-type oxide (MCNO) catalyst was prepared. • MCNO material possesses large specific surface area and superior reducibility. • Non-thermal plasma-MCNO system has excellent toluene decomposition efficiency. • Catalyst combined with plasma enhances CO 2 selectivity and O 3 decomposition rate. A novel strategy for removal of toluene by non-thermal plasma (NTP) coupled with metal-organic frameworks (MOFs) derived catalyst was proposed in this work. The MOF-derived porous trimetallic oxide catalyst (MnCoNiO x , MCNO) was prepared by simple pyrolysis of a MOF-74(Mn-Co-Ni) precursor. We found that the MCNO material can well synergy with NTP in total decomposition of toluene owing to its high specific surface area, regular porous structure and excellent reducibility, which endow superior catalytic activity and CO 2 selectivity of NTP-MCNO system compared to that of NTP-MnO x , NTP-CoO x and NTP-NiO x. For instance, the toluene degradation efficiency can reach up to 75.7% in NTP-MCNO system with a low specific input energy of 101 J/L, much higher than that of NTP-MnO x (59.3%), NTP-CoO x (70.9%), NTP-NiO x (65.0%) and NTP alone (42.9%). Moreover, the formed ozone (O 3) can be well-controlled by the NTP-MCNO system due to the spinel-type oxides (MCNO) derived from MOF could generate more open-formwork structure and improve the mobility of oxygen. The results of this work would shed light on rational design and preparation of spinel-type oxides for oxidation applications, which provides guidance for further improvement of plasma-catalysis system. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysts with single‐atom active sites offer a means of expanding the industrial application of noble metal catalysts. Herein, an atomically dispersed Pt1‐Co3O4 catalyst is presented, which exhibits an exceptionally high efficiency for the total oxidation of methanol. Experimental and theoretical investigations indicate that this catalyst consists of Pt sites with a large proportion of occupied high electronic states. These sites possess a strong affinity for inactive Co2+ sites and anchor over the surface of (111) crystal plane, which increases the metal–support interaction of the Pt1‐Co3O4 material and accelerates the rate of oxygen vacancies regeneration. In turn, this is determined to promote the coadsorption of the probe methanol molecule and O2. Density functional theory calculations confirm that the electron transfer over the oxygen vacancies reduces both the methanol adsorption energy and activation barriers for methanol oxidation, which is proposed to significantly enhance the dissociation of the CH bond in the methanol decomposition reaction. This investigation serves as a solid foundation for characterizing and understanding single‐atom catalysts for heterogeneous oxidation reactions. [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]

Current coupled climate models contain large biases in simulating tropical cyclogenesis, reducing the confidence in tropical cyclone (TC) projection. In this study, we investigated the influence of sea surface temperature (SST) biases on TC genesis in the Coupled Model Intercomparison Project phase 6 simulations from 1979 to 2014. Positive TC genesis biases were found over the tropical central North Pacific (CNP) in most of climate models, including the high-resolution models. Compared to coupled models, TC genesis density (TCGD) simulations over CNP in uncoupled models forced by observational SST improved obviously. A warm SST bias over the tropical CNP in the coupled models is the main cause of TC genesis biases. The SST bias–induced diabatic heating leads to an anomalous Gill-type atmospheric circulation response, which contributes to a series of favorable environmental conditions for TC formation over the CNP. Numerical experiments were also performed with HiRAM to demonstrate the influence of SST biases on the TCGD simulation, further confirming our conclusion. The current results highlight the importance of improving TC simulation in state-of-the-art climate models by reducing SST simulation bias. [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]

Light alkanes extensively presented in industrial exhausts have led tremendous harm to the atmospheric environment and human health. However, the catalytic destruction of light alkanes generally operates at elevated temperatures and the consequent reaction by-products are inevitably produced. It is therefore of great significance to engineer catalysts with superior thermal stability, internal activity and selectivity. Herein, we developed a Pd cluster/CeO 2 catalyst (Pd n /CeO 2) by a scalable deposition precipitation strategy, which demonstrates unexpected activity and thermal stability in the presence of 5% H 2 O attributing to abundant unsaturated Pd metal sites and excellent oxygen dissociation performance. Pd n /CeO 2 possesses a highly efficient C-C cleavage capability due to the persistent formation of a large number of oxygen vacancies. In comparison, the Pd 1 /CeO 2 catalyst, which is preferential for C-H bond cleavage and inactive for C-C bond cracking, produces remarkable hazardous organic by-products such as propyne and propylene, inhibiting the continuous decomposition of propane. The present study sheds critical insights into engineering efficient and stable catalysts for light alkane destruction. [Display omitted] • Strong metal-support interaction and unsaturated Pd sites were obtained on Pd n /CeO 2. • Pd cluster/CeO 2 (Pd n /CeO 2) exhibits high propane destruction ability and thermal stability. • Pd n /CeO 2 has excellent C-C cleavage ability owing to renewable oxygen vacancies. • The production of harmful organic by-products is effectively reduced over Pd n /CeO 2. • Saturated Pd single atom catalyst (Pd 1 /CeO 2) is preferentially for C-H bonds cleavage. [ABSTRACT FROM AUTHOR]

[Display omitted] • g-C 3 N 4 /Ni/CdS is constructed by insetting highly dispersed Ni atoms between g-C 3 N 4 and CdS. • The resultant g-C 3 N 4 /Ni/CdS displays a high H 2 evolution rate of 9.5 mmol/g/h. • Ni atoms dispersed on the surface of g-C 3 N 4 contribute to the intimate deposition of CdS. • Ni atoms facilitate the rapid transfer of charge carriers between g-C 3 N 4 and CdS. Highly efficient interface charge carrier transfer and separation is a primary factor in guaranteeing the performance of hetero photocatalysts. Here, we construct a high-performance g-C 3 N 4 /CdS heterostructure by insetting highly dispersed Ni atoms between g-C 3 N 4 nanosheets and CdS nanoparticles, and the obtained CNN/Ni 500 /CdS-2.4 displays the highest H 2 evolution rate of 9.5 mmol/g/h without the addition of extra co-catalyst, which is about 4.3 times to that of CNN/CdS heterostructure without Ni atom addition. It is found that the significantly enhanced H 2 evolution ability can be ascribed to the dual function of Ni atoms in linking hetero interfaces and facilitating charge transport. The introduced Ni atoms disperse uniformly on the surface of g-C 3 N 4 and thus contributing to the large area uniform and intimately deposition of CdS nanoparticles, which provides sufficient surface-active sites for the photocatalytic reaction. At the same time, due to the good the conductivity, the introduction of Ni atoms dramatically facilitates the rapid transfer of charge carriers between g-C 3 N 4 and CdS and thus accelerating the generation of hydrogen. This work demonstrates the great potential of trace amount of highly dispersed metals on improving the quality of heterojunctions and promoting the photocatalytic ability of heterostructures. [ABSTRACT FROM AUTHOR]

A deterministic Extreme Value Analysis method is of particular importance in an engineering-oriented context. In this paper, three extreme value analysis (EVA) methods, in which annual maxima, monthly maxima or the Peaks-Over-Threshold are fitted into Generalized Extreme Value distribution (GEV) function or Generalized Pareto distribution (GP) function, are used to estimate return values of significant wave height. Sensitivity of return levels on water depth and sampling length is vigorously investigated, based on a 40-year long and high-resolution wave hindcast for the South Yellow Sea (SYS). A spatially-and-temporally varied POT sampling method combined with GP function produces most conservative and confident estimates of return levels for a large return period, but produces wider confidence level than the other two EVA approaches based on GEV function for short return period. In the SYS, the return level estimates are significantly reduced with a longer sample length. However, we find that the reduction is closely related to the long-term trend in extreme wave heights, rather than due to the sampling effect. From deep to shallow waters, spatial inhomogeneity of return levels increases, which should be considered in the engineering practice. • A sophisticated investigation was conducted on the dependence of the return level of extreme wave heights in the SYS to the epistemic and intrinsic factors. • GEV distribution model is more confident in short-term return level estimates, whilst GP distribution model is more confident for long-term return level estimates. • The inter-tidal region although is least sensitive to sampling length for the return level estunates, whilst contains the largest spatial inhomogeneity of extreme wave heights. • A temporal negative long-term trend was found in the return levels of extreme wave height in the SYS. [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]

A triply-nested two-dimensional (2D) ocean circulation model along with observed sea level records are used to study tide-surge interaction along the east coast of the Leizhou Peninsula (LP) which is characterized by extensive mudflats, large tidal ranges and a complex coastline. The dependency of surge maxima on the water level and the phase of tide are respectively investigated using two statistical approaches. Results show that tide-surge interaction along the east coast of the LP is significant, where surges peak 3–6 h before or after the nearest high water. The triply-nested 2D ocean circulation model is used to quantify tide-surge interaction in this region and to investigate its physical cause. The largest amplitudes of tide-surge interaction are found in the shallow water region of the Leizhou Bay, with values up to 1 m during typhoon events. Numerical experiments reveal that nonlinear bottom friction is the main contributor to tide-surge interaction, while the contribution of the nonlinear advective effect can be neglected. The shallow water effect enhances the role of nonlinear bottom friction in determining tide-surge modulation, leaving the surge peaks usually occur on the rising or falling tide. It is also found that the relative contribution of local wind and remote wind is different depending on the storm track and storm intensity, which would finally affect the temporal and spatial distribution of tide-surge interaction during typhoon events. These findings confirm the importance of coupling storm surges and tides for the prediction of storm surge events in regions which are characterized by shallow water depths and large tidal ranges. [ABSTRACT FROM AUTHOR]

A dynamical wind-wave climate simulation covering the North Atlantic Ocean and spanning the whole 21st century under the A1B scenario has been compared with a set of statistical projections using atmospheric variables or large scale climate indices as predictors. As a first step, the performance of all statistical models has been evaluated for the present-day climate; namely they have been compared with a dynamical wind-wave hindcast in terms of winter Significant Wave Height (SWH) trends and variance as well as with altimetry data. For the projections, it has been found that statistical models that use wind speed as independent variable predictor are able to capture a larger fraction of the winter SWH inter-annual variability (68% on average) and of the long term changes projected by the dynamical simulation. Conversely, regression models using climate indices, sea level pressure and/or pressure gradient as predictors, account for a smaller SWH variance (from 2.8% to 33%) and do not reproduce the dynamically projected long term trends over the North Atlantic. Investigating the wind-sea and swell components separately, we have found that the combination of two regression models, one for wind-sea waves and another one for the swell component, can improve significantly the wave field projections obtained from single regression models over the North Atlantic. [ABSTRACT FROM AUTHOR]

ABSTRACT This study investigates the relationship between the wind wave climate and the main climate modes of atmospheric variability in the North Atlantic Ocean. The modes considered are the North Atlantic Oscillation ( NAO), the East Atlantic ( EA) pattern, the East Atlantic Western Russian ( EA/ WR) pattern and the Scandinavian ( SCAN) pattern. The wave dataset consists of buoys records, remote sensing altimetry observations and a numerical hindcast providing significant wave height ( SWH), mean wave period ( MWP) and mean wave direction ( MWD) for the period 1989-2009. After evaluating the reliability of the hindcast, we focus on the impact of each mode on seasonal wave parameters and on the relative importance of wind-sea and swell components. Results demonstrate that the NAO and EA patterns are the most relevant, whereas EA/ WR and SCAN patterns have a weaker impact on the North Atlantic wave climate variability. During their positive phases, both NAO and EA patterns are related to winter SWH at a rate that reaches 1 m per unit index along the Scottish coast ( NAO) and Iberian coast ( EA) patterns. In terms of winter MWD, the two modes induce a counterclockwise shift of up to 65° per negative NAO (positive EA) unit over west European coasts. They also increase the winter MWP in the North Sea and in the Bay of Biscay (up to 1 s per unit NAO) and along the western coasts of Europe and North Africa (1 s per unit EA). The impact of winter EA pattern on all wave parameters is mostly caused through the swell wave component. [ABSTRACT FROM AUTHOR]