Recent Advances in Understanding Multi-scale Climate Variability of the Asian Monsoon

Studies of the multi-scale climate variability of the Asian monsoon are essential to an advanced understanding of the physical processes of the global climate system.In this paper,the progress achieved in this field is systematically reviewed,with a focus on the past several years.The achievements are summarized into the following topics:(1)the onset of the South China Sea summer monsoon;(2)the East Asian summer monsoon;(3)the East Asian winter monsoon;and(4)the Indian summer monsoon.Specifically,new results are highlighted,including the advanced or delayed local monsoon onset tending to be synchronized over the Arabian Sea,Bay of Bengal,Indochina Peninsula,and South China Sea;the basic features of the record-breaking mei-yu in 2020,which have been extensively investigated with an emphasis on the role of multi-scale processes;the recovery of the East Asian winter monsoon intensity after the early 2000s in the presence of continuing greenhouse gas emissions,which is believed to have been dominated by internal climate variability(mostly the Arctic Oscillation);and the accelerated warming over South Asia,which exceeded the tropical Indian Ocean warming,is considered to be the main driver of the Indian summer monsoon rainfall recovery since 1999.A brief summary is provided in the final section along with some further discussion on future research directions regarding our understanding of the Asian monsoon variability.

Prognostic implications of overt congestion in heart failure with preserved ejection fraction and the interaction with spironolactone:Insights from TOPCAT

To the Editor:Heart failure with preserved ejection fraction(HFpEF)is a clinical entity characterized by impaired diastolic function.Until recently,there have been few studies directly evaluating how volume status impacts future cardiac events for patients with HFpEF.Evidence supporting the application of spironolactone in HFpEF is mainly derived from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist(TOPCAT)trial.Even though primary analysis of the trial reached a neutral result,subgroup and subsequent post hoc analyses have confirmed its efficacy in selected groups of patients,suggesting that identifying the potential subgroups of patients who would benefit from spironolactone treatment is important.[1]Data regarding the impact of congestion status on the efficacy of spironolactone in HFpEF are lacking.

Understanding the role of SST anomaly in extreme rainfall of 2020 Meiyu season from an interdecadal perspective

Extreme Meiyu rainfall in 2020,starting from early June to the end of July,has occurred over the Yangtze River valley(YRV),with record-breaking accumulated precipitation amount since 1961.The present study aims to examine the possible effect of sea surface temperature(SST)on the YRV rainfall in Meiyu season from the interdecadal perspective.The results indicate that YRV rainfall in June exhibits more significant variability on interdecadal time scale than that in July.The interdecadal-filtered atmospheric circulation in June,compared with the counterpart in July,shows a more predominant and better-organized Western North Pacific Anticyclone(WNPAC)anomaly,which could transport abundant moisture to the YRV by anomalous southwesterly prevailing in northwestern flank of anomalous WNPAC.Both observation and numerical experiment indicate that the interdecadal change of the SST anomaly in tropical western Indian Ocean(TWI)from preceding May to June can significantly affect the anomalous WNPAC,leading to enhanced YRV rainfall in June.The TWI SST anomaly shifts from a cold phase to a warm phase around the early 2000s,with a magnitude of 0.7°C in 2020,which implies that such interdecadal warming might partly contribute to the heavy rainfall in June 2020 by providing a large-scale favorable background flow.

Effect of concomitant anti-solvent engineering on perovskite grain growth and its high efficiency solar cells

The grain boundaries and interface properties in the active layers of perovskite solar cells(PSCs)are important factors affecting the performances of the devices.In this work,a simple and fast concomitant annealing process is established by inducing the secondary growth of the grains using the anti-solvent o-dichlorobenzene(o-PhCl2)or chlorobenzene(PhCl)to suppress the volatilization of solvent molecules during the FA0.80MA0.15Cs0.05Pb(I0.85Br0.15)3(FA,CH5N2+,formamidine;MA,CH3NH3+,methylamine)film annealing procedure.The effects of anti-solvent molecules on the phase transformation,grain boundary fusion and morphology evolution of perovskite films are systematically investigated by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The results indicate that anti-solvent molecules can inhibit solvent evaporation in the active layers and promote crystallite dissolution and ordered secondary growth along the surfaces of large grains.That can promote the formation of large grains and the passivation of surface defects,and can be favorable for the separation and transportation of photocarriers in the active layer.Consequently,the power conversion efficiency(PCE)of PSCs can be effectively improved,with a PCE of 20.72%being achieved by a secondary growth perovskite film optimized with o-PhCl2.Moreover,the efficiency remains at 85%of its initial value after 2400 h of treatment in a natural indoor environment with a relative humidity of 45±5%.