高压氧干预对高海拔移居者睡眠质量、抑郁状况及HRV的调节效应

为了探讨高压氧干预是否可以改善高原移居者的睡眠质量、抑郁状况和自主神经系统的平衡性,选取成年后移居高海拔地区的44名大学生作为研究对象,随机分为实验组和对照组.两组被试者在20次高压氧干预前、干预后和干预后第15天分别测评匹兹堡睡眠质量指数量表(PSQI)、流调中心抑郁量表(CES-D)及心率变异性(HRV).结果发现:1)经过20次的高压氧干预,实验组的PSQI、CES-D得分显著下降(P_(s)<0.05);2)实验组HRV中的HF(高频功率)数值显著提高(P<0.05)、LF(低频功率)及LF/HF数值显著下降(P_(s)<0.05);而对照组的前后所测各指标之间均不存在显著性差异(P_(s)>0.05).结论:高压氧干预改善了高原移居者睡眠、抑郁状况及自主神经系统的平衡性,且存在明显的预后效应.

Extent and Structure of Phenotypic Variability in Solenostemon rotundifolius Germplasm from Ghana and Burkina Faso

Solenostemon rotundifolius is a species belonging to the Lamiaceae family. It is currently one of the minor plants of high socio-economic interest. One of the limitations to promoting this species in Burkina Faso is the lack of varieties that meet consumers’ demands. Implementing a breeding program is an important step toward achieving this goal. Such a program is based on the variability of agronomical traits of interest within evaluated germplasm. This study aimed to assess the level of two germplasms variability of S. rotundifolius from Ghana and Burkina Faso for traits related to vegetative development, cycle, and yield. Agromorphological characterization of 174 accessions, including 116 from Ghana and 58 from Burkina Faso was carried out in Randomised Complete Block Design with three replications. The characterization was made on the basis of fifteen (15) quantitative traits related to the canopy and leaf size, the cycle, and the yield. Analysis of variance revealed significant differences between accessions within each germplasm for all the evaluated traits. The analysis of the structuration of this agromorphological variability allowed organizing the accessions into different groups. These results could lead to the identification of accessions within each germplasm for breeding purposes or future research on genotype-environment interactions.

Intraseasonal variability of the Kuroshio observed via mooring at 18°N

Insufficient observations near the origin of the Kuroshio have led to incomplete understanding of the intraseasonal variability(ISV)of the Kuroshio.Direct measurements of the Kuroshio velocity were performed with an array of three profiler moorings(122.7°E,123°E,and 123.3°E)along 18°N from January 2018 to February 2020.The ISV of the Kuroshio at 18°N was investigated based on a combination of mooring observations and global high-resolution HYbrid Coordinate Ocean Model reanalysis data.The estimated time-averaged transport in the upper 350 m across the observation transect was 6.5±2.6 Sv(1.0 Sv=10^(6)m^(3)/s).Two significant ISV peaks at 50-60 and~100 d were recognized in the power spectra of the meridional velocity and transport.Further analysis indicated that the ISV at 50-60 d was caused by westward-propagating eddies at average propagation speed of~13 cm/s and wavelength of~635 km.Another ISV peak at~100 d was mainly caused by northward-propagating eddies generated in the North Equatorial Current region.Further investigation indicated that the ISV of the Kuroshio at 18°N is dominated by meridional transport,rather than by the zonal migration of the Kuroshio main axis.Our findings provide a better understanding of the ISV of the Kuroshio east of Luzon Island.

Geospatial Variability of Cholera Cases in Malawi Based on Climatic and Socioeconomic Influences

Cholera remains a public health threat in most developing countries in Asia and Africa including Malawi with seasonal recurrent outbreaks. Malawi’s recent Cholera outbreak in 2022 and 2023, exhibited higher morbidity and mortality rates than the past two decades. Lack of spatiotemporal-based technology and variability assessment tools in Malawi’s Cholera monitoring and management, limit our understanding of the disease’s epidemiology. The present work developed a spatiotemporal variability model for Cholera disease at district level and its relationship to socioeconomic and climatic factors based on cumulative confirmed Cholera cases in Malawi from March 2022 to July 2023 using Z-score statistic and multiscale geographically weighted regression (MGWR) in a Geographical Information System (GIS). We found out that socioeconomic factors such as access to safe drinking water, population density and poverty level, and climatic factors including temperature and rainfall strongly influenced Cholera prevalence in a complex and multifaceted manner. The model shows that Lilongwe, Mangochi, Blantyre and Balaka districts were highly vulnerable to Cholera disease followed by lakeshore districts of Salima, Nkhotakota, Nkhata-Bay and Karonga than other districts. We recommend strategic measures such as Water, Sanitation, and Hygiene (WASH) interventions, community awareness on proper water storage, Cholera case management, vaccination campaigns and spatial-based surveillance systems in the most affected districts. This research has shown that MGWR, as a surveillance system, has the potential of providing insights on the disease’s spatial patterns for public health authorities to identify high-risk districts and implement early response interventions to reduce the spread of the disease.

Responses of Annual Variability of Vegetation NPP to Climate Variables Using Satellite Techniques in Gadarif State, Sudan

Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as climate, soils, plant characteristics and human activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from MODIS to assess the response of NPP to climate variables in Gadarif State, from 2000 to 2010. The correlations between NPP and climate variables (temperature and precipitation) are calculated using Pearson’s Correlation Coefficient and ordinary least squares regression. The main results show the following 1) the correlation Coefficient between NPP and mean annual temperature is Somewhat negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area;2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and somewhat negative in Galabat and Rahd areas. This study demonstrated that the correlation analysis between NPP and climate variables (precipitation and temperature) gives reliably result of NPP responses to climate variables that is clearly in a very large scale of study area.

Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial variability.To overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil strata.The three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-Lind-Rackwits-Fiessler recursive algorithm(iHLRF)as well as its inverse analysis formulation.The proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face stability.To demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random fields.The results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into account.Furthermore,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil strata.The results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic problems.It is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex soil strata.

A comprehensive review of heart rate variability as an indicator in the regulation of the autonomic nervous system by acupuncture:a bibliometric analysis

This study sought to conduct a bibliometric analysis of acupuncture studies focusing on heart rate variability(HRV)and to investigate the correlation between various acupoints and their effects on HRV by utilizing association rule mining and network analysis.A total of 536 publications on the topic of acupuncture studies based on HRV.The disease keyword analysis revealed that HRV-related acupuncture studies were mainly related to pain,inflammation,emotional disorders,gastrointestinal function,and hypertension.A separate analysis was conducted on acupuncture prescriptions,and Neiguan(PC6)and Zusanli(ST36)were the most frequently used acupoints.The core acupoints for HRV regulation were identified as PC6,ST36,Shenmen(HT7),Hegu(LI4),Sanyinjiao(SP6),Jianshi(PC5),Taichong(LR3),Quchi(LI11),Guanyuan(CV4),Baihui(GV20),and Taixi(KI3).Additionally,the research encompassed 46 reports on acupuncture animal experiments conducted on HRV,with ST36 being the most frequently utilized acupoint.The research presented in this study offers valuable insights into the global research trend and hotspots in acupuncture-based HRV studies,as well as identifying frequently used combinations of acupoints.The findings may be helpful for further research in this field and provide valuable information about the potential use of acupuncture for improving HRV in both humans and animals.

Analysis of Extreme Temperature Variability in Rwanda

The temperature is one of the most important factors in weather and climate forecasting.Studying its behaviour is crucial to understanding climate variability,which could vary spatially and temporally at local,regional,and global scales.Several recent studies on air temperature findings show that the Earth’s near surface air temperature increased between 0.6℃ and 0.8℃ throughout the twentieth century.Using temperature records from ten meteorological stations,this study examined climate variability in Rwanda from the 1930s to 2014.The air temperature data were collected from Meteo Rwanda.Before making the analysis,the authors used software,such as Excel 2007 and INSTAT to control the quality of the raw data.The analysis of maxima and minima indicated that the trends of maximum air temperature were positive and significant at height meteorological stations,whereas the trends for minimum air temperature were found to be at 10 meteorological stations.For all parameters analysed,Kigali Airport meteorological station indicated the higher significance of the trends.The majority of meteorological stations showed an increase in both hot days and nights,confirming Rwanda’s warming over time.The analysis of average seasonal air temperature showed almost similar trends even though not all were significant.This similarity in trends could be attributed to the fact that Rwanda’s short and long dry seasons coincide with rainy seasons.

Influence of Continental Atmospheric Forcing on the Decadal Variability of the West African Monsoon

The West African Monsoon (WAM) is characterized by strong decadal and multi-decadal variability and the impacts can be catastrophic for the local populations. One of the factors put forward to explain this variability involves the role of atmospheric dynamics, linked in particular to the Saharan Heat Low (SHL). This article addresses this question by comparing the sets of preindustrial control and historical simulation data from climate models carried out in the framework of the CMIP5 project and observations data over the 20th century. Through multivariate statistical analyses, it was established that decadal modes of ocean variability and decadal variability of Saharan atmospheric dynamics significantly influence decadal variability of monsoon precipitation. These results also suggest the existence of external anthropogenic forcing, which is superimposed on the decadal natural variability inducing an intensification of the signal in the historical simulations compared to preindustrial control simulations. We have also shown that decadal rainfall variability in the Sahel, once the influence of oceanic modes has been eliminated, appears to be driven mainly by the activity of the Arabian Heat Low (AHL) in the central Sahel, and by the structure of the meridional temperature gradient over the inter-tropical Atlantic in the western Sahel.

稳心颗粒对老年慢性射血分数保存的心衰(HFpEF)患者HRV的效果观察

探究中成药稳心颗粒对老年慢性射血分数保存的心衰(heart failure with preserved ejection fraction,HFpEF)患者心率变异性(heart rate variability,HRV)的效果。方法 选取2021年9月-2022年9月在安徽理工大学第一附属医院(淮南市第一人民医院)接受治疗的80例心率变异性(HRV)异常老年慢性射血分数保存的心衰(HFpEF)患者,分为观察组和对照组各40例。对照组给予常规抗心衰西药治疗,观察组在对照组基础上加以中成药稳心颗粒治疗。1年后进行动态心电图检查测定两组人员的HRV参数进行统计对比,并对比两组人员的自主神经功能障碍症状:包括未能明确具体器质性原因的便秘、泌尿系统症状(如尿频、尿急、尿失禁)、皮肤改变(麻木、发痒等)、心悸和呼吸紧迫感,以及排汗异常、畏寒促冷等体温调节异常,和直立性眩晕和(或) 发作性头晕等。结果 (1)观察组与对照组HRV参数差异具有统计学意义(P<0.05);观察组优于对照组(2)两组患者出现自主神经功能障碍症状具有统计学意义(P<0.05),观察组优于对照组。结论 中成药稳心颗粒对改善老年慢性HFpEF患者HRV有益。

A teleconnection pattern of upper-tropospheric circulation anomalies over the Eurasian continent associated with the interannual variability of atmospheric convection over the tropical western North Pacific in July

热带西北太平洋大气对流的年际变化对东亚夏季气候有着显著影响,而且受到前冬ENSO的影响.然而,还有相当多的西北太平洋对流年际变化不能由前冬ENSO解释.本文表明,7月西北太平洋对流受到欧亚大陆对流层上层遥相关型的显著影响,且这一影响与前冬ENSO的影响程度相当.该遥相关型表现为位于欧洲的气旋式环流异常,中亚的反气旋式环流异常和东亚带状延伸的气旋式环流异常,并表现为7月对流层上层环流的第一主模态.基于本文的结果并结合前人的研究,作者认为这一遥相关型能通过亚洲急流出口区附近的罗斯贝波破碎引起西北太平洋对流异常.

桂枝加龙骨牡蛎汤加减对围绝经期快速性心律失常疗效及对HRV、E_(2)、FSH的影响

目的观察桂枝龙骨牡蛎汤加减对围绝经期快速性心律失常的疗效及对心率变异性(HRV)、血清雌二醇(E_(2))、卵泡刺激素(FSH)的影响。方法将纳入的104例患者随机分为对照组、治疗组各52例。对照组予西医控制心率治疗,治疗组在对照组基础上予桂枝龙骨牡蛎汤加减治疗,疗程为4周,观察比较两组心率变异性指标[全部窦性心搏RR间期(SDNN)、5 min节段平均正常心动周期标准差(SDNNidx)、相邻正常心动周期差值均方根(rMSSD)、RR间期平均值标准差(SDANN)]、中医证候积分以及血清E_(2)、FSH水平并观察其疗效。结果治疗后治疗组早搏患者总有效率88.89%大于对照组总有效率75.00%,室上速患者总有效率95.24%大于对照组85.00%,室速患者总有效率93.75%大于对照组77.78%,房颤患者总有效率83.33%大于对照组66.67%(均P<0.05),治疗后两组心率变异性指标:SDNN、SDNNidx、rMSSD、SDANN水平提高(P<0.05),且治疗组效果更优,组间比较差异具有统计学意义(均P<0.05)。两组治疗1、2、4周后与治疗前相比中医证候积分降低(P<0.05),且治疗组低于对照组(P<0.05)。两组治疗后血清E_(2)水平相比治疗前升高,FSH水平相比治疗前降低(均P<0.05)。各组治疗期间无不良反应,治疗后各项实验室指标均正常,无并发症产生。结论桂枝加龙骨牡蛎汤加减对女性围绝经期快速性心律失常疗效显著,可明显改善患者的临床症状及中医证候,改善心率变异性指标及雌激素水平,显著提高患者生活质量。

Heart Rate Variability: On the Importance to Perform HRV Analysis in Subjects Affected from Muscular Dystrophy

This paper discusses a case of muscular dystrophy on which it has been performed HRV analysis. The results that we obtain evidence that the subject delineates a net ANS dysfunction. All the basic parameters relating standard time and frequency domain of HRV analysis result profoundly altered. Examination by Poicaré plot evidences in particular that the subject has an atrial fibrillation. Non linear indexes ApEn and Samp En evidence the very high condition of risk of the subject. The merging indication is for the cardiologist and scholars in cardiovascular disease to perform always ANS investigation in subjects in case of muscular dystrophy. After the NPT treatment, the subject obtains a net improvement.

Recent Enhancement in Co-Variability of the Western North Pacific Summer Monsoon and the Equatorial Zonal Wind

The western North Pacific summer monsoon(WNPSM)is an important subcomponent of the Asian summer monsoon.The equatorial zonal wind(EZW)in the lower troposphere over the western Pacific may play a critical role in the evolution of the El Niño-Southern Oscillation(ENSO).The possible linkage between the EZW over the western Pacific and the offequatorial monsoonal winds associated with the WNPSM and its decadal changes have not yet been fully understood.Here,we find a non-stationary relationship between the WNPSM and the western Pacific EZW,significantly strengthening their correlation around the late 1980s/early 1990s.This observed shift in the WNPSM–EZW relationship could be explained by the changes in the related sea surface temperature(SST)configurations across the tropical oceans.The enhanced influence from the springtime tropical North Atlantic,summertime tropical central Pacific,and maritime continent SST anomalies may be working together in contributing to the recent intensified WNPSM–EZW co-variability.The observed recent strengthening of the WNPSM–EZW relationship may profoundly impact the climate system,including prompting more effective feedback from the WNPSM on subsequent ENSO evolution and bolstering a stronger biennial tendency of the WNPSM–ENSO coupled system.The results obtained herein imply that the WNPSM,EZW,ENSO,and the tropical North Atlantic SST may be closely linked within a unified climate system with a quasi-biennial rhythm occurring during recent decades,accompanied by a reinforcement of the WNPSM–ENSO interplay quite possibly triggered by enhanced tropical Pacific–Atlantic cross-basin interactions.These results highlight the importance of the tropical Atlantic cross-basin influences in shaping the spatial structure of WNPSM-related wind anomalies and the WNPSM–ENSO interaction.

Synchronous measurements of prefrontal activity and pulse rate variability during online video game playing with functional near-infrared spectroscopy

Interactions between the central nervous system(CNS)and autonomic nervous system(ANS)play a crucial role in modulating perception,cognition,and emotion production.Previous studies on CNS–ANS interactions,or heart–brain coupling,have often used heart rate variability(HRV)metrics derived from electrocardiography(ECG)recordings as empirical measurements of sympathetic and parasympathetic activities.Functional near-infrared spectroscopy(fNIRS)is a functional brain imaging modality that is increasingly used in brain and cognition studies.The fNIRS signals contain frequency bands representing both neural activity oscillations and heartbeat rhythms.Therefore,fNIRS data acquired in neuroimaging studies can potentially provide a single-modality approach to measure task-induced responses in the brain and ANS synchronously,allowing analysis of CNS–ANS interactions.In this proof-of-concept study,fNIRS was used to record hemodynamic changes from the foreheads of 20 university students as they each played a round of multiplayer online battle arena(MOBA)game.From the fNIRS recordings,neural and heartbeat frequency bands were extracted to assess prefrontal activities and shortterm pulse rate variability(PRV),an approximation for short-term HRV,respectively.Under the experimental conditions used,fNIRS-derived PRV metrics showed good correlations with ECG-derived HRV golden standards,in terms of absolute measurements and video game playing(VGP)-related changes.It was also observed that,similar to previous studies on physical activity and exercise,the PRV metrics closely related to parasympathetic activities recovered slower than the PRV indicators of sympathetic activities after VGP.It is concluded that it is feasible to use fNIRS to monitor concurrent brain and ANS activations during online VGP,facilitating the understanding of VGP-related heart–brain coupling.

Alpha-rhythm stimulation using brain entrainment enhances heart rate variability in subjects with reduced HRV

In the present research, we have used the brain entrainment (BWE) treatment simultaneously recording time series data of R-R intervals of the ECG during rest condition. In detail, we have used alpha brain stimulation and we have found that it induces an enhancement of HRV, particularly in Total Variability and Vagal Modulation activities. The experiment has been performed by us on ten subjects with age ranging from 20 to 70 years old. The risk induced from low HRV is by this time well known in literature. Therefore, the obtained result promises to be of valuable interest not only in terms of the basic neurological investigation but also because it delineates new possibilities in terms of clinical application.

Relationship between glycemic variability and cognitive function in lacune patients with type 2 diabetes

BACKGROUND Lacunes are the manifestations of lacunar infarction which can lead many patients to the clinical outcome of disability or dementia.However,the relationship between lacune burden,cognitive function and blood glucose fluctuation in patients with type 2 diabetes mellitus(T2DM)complicated with lacunes is not very clear.AIM To explore the correlation between glucose variability,lacune burden and cognitive function in patients with lacunes complicated with T2DM.METHODS The clinical and imaging data of 144 patients with lacunes combined with T2DM were reviewed retrospectively.72 h continuous glucose monitoring was performed.The Montreal Cognitive Assessment was used to assess cognitive function.The burden of lacunes was evaluated using magnetic resonance imaging performance.Multifactorial logistic regression analysis was used to study the affecting the lacune load and cognitive impairment in patients.To predict the value of patients’cognitive impairment with lacunes complicated with T2DM,a receiver operating characteristic(ROC)curve and a nomogram prediction model were constructed.RESULTS The standard deviation(SD)of the average blood glucose concentration,percentage coefficient of variation(%CV)and time of range(TIR)were significantly different between the low and the high load groups(P<0.05).The SD,%CV and TIR of the cognitive impairment group and non-cognitive impairment group were significantly different(P<0.05).SD(odds ratio(OR):3.558,95%confidence interval(CI):1.268-9.978,P=0.006),and%CV(OR:1.192,95%CI:1.081-1.315,P<0.05)were the risk factors for an increased infarct burden in lacunes patients complicated with T2DM.TIR(OR:0.874,95%CI:0.833-0.928,P<0.05)is a protective factor.In addition,an increased SD(OR:2.506,95%CI:1.008-6.23,P=0.003),%CV(OR:1.163,95%CI:1.065-1.270,P<0.05)were the risk factors for cognitive impairment in patients with lacunes complicated with T2DM,TIR(OR:0.957,95%CI:0.922-0.994,P<0.05)is a protective factor.A nomogram prediction model of the risk of cognitive impairment was established based on SD,%CV and TIR.Decision curve analysis and the internal calibration analysis were used for internal verification and showed that the model was clinical benefit.The area under the ROC curves for predicting cognitive impairment in patients with lacunes complicated with T2DM was drawn were%CV:0.757(95%CI:0.669-0.845,P<0.05),TIR:0.711(95%CI:0.623-0.799,P<0.05).CONCLUSION Blood glucose variability is closely associated with the level of lacune burden and cognitive dysfunction in lacune patients combined with T2DM.%CV,TIR have a certain predictive effect in cognitive impairment in lacune patients.

Impacts of Sea Surface Temperature on the Interannual Variability of Winter Haze Days in Guangdong Province

The impact of sea surface temperature(SST)on winter haze in Guangdong province(WHDGD)was analyzed on the interannual scale.It was pointed out that the northern Indian Ocean and the northwest Pacific SST play a leading role in the variation of WHDGD.Cold(warm)SST anomalies over the northern Indian Ocean and the Northwest Pacific stimulate the eastward propagation of cold(warm)Kelvin waves through the Gill forced response,causing Ekman convergence(divergence)in the western Pacific,inducing abnormal cyclonic(anticyclonic)circulation.It excites the positive(negative)Western Pacific teleconnection pattern(WP),which results in the temperature and the precipitation decrease(increase)in Guangdong and forms the meteorological variables conditions that are conducive(not conducive)to the formation of haze.ENSO has an asymmetric influence on WHDGD.In El Niño(La Niña)winters,there are strong(weak)coordinated variations between the northern Indian Ocean,the northwest Pacific,and the eastern Pacific,which stimulate the negative(positive)phase of WP teleconnection.In El Niño winters,the enhanced moisture is attributed to the joint effects of the horizontal advection from the surrounding ocean,vertical advection from the moisture convergence,and the increased atmospheric apparent moisture sink(Q2)from soil evaporation.The weakening of the atmospheric apparent heat source(Q1)in the upper layer is not conducive to the formation of inversion stratification.In contrast,in La Niña winters,the reduced moisture is attributed to the reduced upward water vapor transport and Q2 loss.Due to the Q1 increase in the upper layer,the temperature inversion forms and suppresses the diffusion of haze.

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.

Dynamical Predictability of Leading Interannual Variability Modes of the Asian-Australian Monsoon in Climate Models

The dynamical prediction of the Asian-Australian monsoon(AAM)has been an important and long-standing issue in climate science.In this study,the predictability of the first two leading modes of the AAM is studied using retrospective prediction datasets from the seasonal forecasting models in four operational centers worldwide.Results show that the model predictability of the leading AAM modes is sensitive to how they are defined in different seasonal sequences,especially for the second mode.The first AAM mode,from various seasonal sequences,coincides with the El Niño phase transition in the eastern-central Pacific.The second mode,initialized from boreal summer and autumn,leads El Niño by about one year but can exist during the decay phase of El Niño when initialized from boreal winter and spring.Our findings hint that ENSO,as an early signal,is conducive to better performance of model predictions in capturing the spatiotemporal variations of the leading AAM modes.Still,the persistence barrier of ENSO in spring leads to poor forecasting skills of spatial features.The multimodel ensemble(MME)mean shows some advantage in capturing the spatiotemporal variations of the AAM modes but does not provide a significant improvement in predicting its temporal features compared to the best individual models in predicting its temporal features.The BCC_CSM1.1M shows promising skill in predicting the two AAM indices associated with two leading AAM modes.The predictability demonstrated in this study is potentially useful for AAM prediction in operational and climate services.