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rainfall的相关文献在1989年到2023年内共计225篇,主要集中在肿瘤学、大气科学(气象学)、海洋学 等领域,其中期刊论文225篇、相关期刊52种,包括地学前缘、热带气象学报:英文版、大气科学进展:英文版等; rainfall的相关文献由760位作者贡献,包括Kwadwo Owusu、Nana Ama Browne Klutse、Philbert M. Luhunga等。

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rainfall

-研究学者

  • Kwadwo Owusu
  • Nana Ama Browne Klutse
  • Philbert M. Luhunga
  • Abdur Rahman
  • Agnes L. Kijazi
  • Augusto J. Pereira Filho
  • Ayman G. Awadallah
  • Claudio Lucianaz
  • David Chikodzi
  • David Cudjoe Adukpo
  • 期刊论文

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    • Chibuike Chiedozie IBEBUCHI
    • 摘要: The positive phase of the subtropical Indian Ocean dipole(SIOD)is one of the climatic modes in the subtropical southern Indian Ocean that influences the austral summer inter-annual rainfall variability in parts of southern Africa.This paper examines austral summer rain-bearing circulation types(CTs)in Africa south of the equator that are related to the positive SIOD and the dynamics through which specific rainfall regions in southern Africa can be influenced by this relationship.Four austral summer rain-bearing CTs were obtained.Among the four CTs,the CT that featured(i)enhanced cyclonic activity in the southwest Indian Ocean;(ii)positive widespread rainfall anomaly in the southwest Indian Ocean;and(iii)low-level convergence of moisture fluxes from the tropical South Atlantic Ocean,tropical Indian Ocean,and the southwest Indian Ocean,over the south-central landmass of Africa,was found to be related to the positive SIOD climatic mode.The relationship also implies that positive SIOD can be expected to increase the amplitude and frequency of occurrence of the aforementioned CT.The linkage between the CT related to the positive SIOD and austral summer homogeneous regions of rainfall anomalies in Africa south of the equator showed that it is the principal CT that is related to the inter-annual rainfall variability of the south-central regions of Africa,where the SIOD is already known to significantly influence its rainfall variability.Hence,through the large-scale patterns of atmospheric circulation associated with the CT,the SIOD can influence the spatial distribution and intensity of rainfall over the preferred landmass through enhanced moisture convergence.
    • WANG Jiancheng; YUE Fange; ZHAN Haicong; KANG Hui; XIE Zhouqing
    • 摘要: Due to the harmful impacts on the ecosystem and even human health,mercury(Hg)compounds in the environment deserve serious concern.Atmospheric mobilization and exchange at the air-sea interface are important processes in biogeochemical cycling of Hg.Relying on the 30th(2013/2014),31st(2014/2015),and 33rd(2016/2017)Chinese National Antarctic Research Expedition aboard R/V Xuelong,we found significant rising gaseous elemental mercury(GEM)concentrations over the equatorial Central Indo-Pacific region.Excluding the contribution of anthropogenic,volcanic and biomass burning emissions,the enhanced GEM in marine boundary layer was likely due to the combined actions of two driving factors drove by the Inter-Tropical Conversion Zone(ITCZ):(1)intense wet deposition of Hg,followed by subsequent rapid photoreduction and vast evasion from the surface sea;and(2)the regional low-level convergence of airflow that caused the mass accumulation of GEM in air.In addition,apparently higher GEM concentration level in the equatorial Central Indo-Pacific than in the Southern Ocean was observed in one cruise.Further investigation suggests that apart from the ITCZ corresponded mechanisms,the effects of spatial differences in anthropogenic emissions and more significant GEM oxidation in Antarctic sea should play roles in this phenomenon.
    • Yu DU; Yian SHEN; Guixing CHEN
    • 摘要: Coastal marine boundary layer jets(CMBLJs)play an important role in coastal and inland rainfall in South China.Using 21 years of ERA5 and CMORPH rainfall data,two main CMBLJs are found,one on each side of Hainan Island(named BLJ-WEST and BLJ-EAST),which are always strengthened jointly.Both CMBLJs often occur in the pre-summer rainy season and exhibit an evident diurnal cycle with a maximum at night.With the emergence of the CMBLJs,rainfall is significantly enhanced in South China,particularly downstream of each CMBLJ.The response of rainfall to the CMBLJs is mainly attributed to convergence at the terminus of each CMBLJ,terrain-induced lifting,and relevant atmospheric stratification.Coastal rainfall downstream of the BLJ-WEST is much weaker than that downstream of the BLJ-EAST because of higher CIN over the Beibu Gulf,which is caused by lower temperature lapse rates and adiabatic heating in the lee of the Annamite Range.The inland rainfall increases along with CMBLJ intensity,whereas coastal rainfall reaches a maximum in the presence of moderate CMBLJs rather than stronger CMBLJs.Stronger CMBLJs induce stronger dynamic lifting but higher CIN near the coastal area.Additionally,CAPE near the coast does not become highest with strongest CMBLJs,because the CAPE generation contributed by coastal dynamic lifting can be offset by the negative contribution caused by the horizontal advection of cold and dry air from the Indochina Peninsula.Therefore,anomalous dynamic lifting,moisture flux convergence,and CAPE/CIN associated with CMBLJ intensity jointly result in anomalous rainfall.
    • Vinay Kumar Gautam; Mahesh Kothari; P.K.Singh; S.R.Bhakar; K.K.Yadav
    • 摘要: Groundwater accounts for about half of the water use for irrigation in India.The fluctuation pattern of the groundwater level is examined by observing rainfall replenishment and monitoring wells.The southern part of Rajasthan has experienced abrupt changes in rainfall and has been highly dependent on groundwater over decades.This study presents the impact of over-dependence on groundwater usage for irrigation and other purposes,spatially and temporally.Hence,the objective of this study is to examine the groundwater level trend by using statistical analysis and geospatial technique.Rainfall factor was also studied in groundwater level fluctuation during 2009-2019.To analyze the influence of each well during recharge or withdrawal of groundwater,thiessien polygonswere generated from them.In the Jakham River basin,75 wells have been identified for water level trend study using the Mann-Kendall statistical test.The statistics of trend analysis show that 15%wells are experiencing water level decline in pre-monsoon,while very low percentage of wells have such trend during post-monsoon season.The average rate of water level decline is 0.245 m/a in pre-monsoon and 0.05 m/a in post-monsoon.The aquifer recharge potential is also decreasing by year.it is expected that such type of studies will help the policy makers to adopt advanced management practices to ensure sustainable groundwater resource management.
    • Fasheng Miao; Yiping Wu; Ákos Török; Linwei Li; Yang Xue
    • 摘要: Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside landslides.Geotechnical centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required geo-stress.In this study,the Liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall condition.Using the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep displacement.The analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse cracks with wide of 1–5 mm appeared during the model test,of which 3 cracks at the toe landslide were caused by reservoir water fluctuation,and the cracks at the middle and rear part were caused by rainfall.During rainfall process,the maximum displacement of landslide model reaches 3 cm.And the maximum deformation of the model exceeds 12 cm at the drainage stage.The failure process of the slope model can be divided into four stages:microcracks appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure stage.When the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure pattern.The failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides.
    • 李婵珠; 杨崧; 莫伟强; 张劲梅; 魏维
    • 摘要: In this study,we assess the prediction for May rainfall over southern China(SC)by using the NCEP CFSv2 outputs.Results show that the CFSv2 is able to depict the climatology of May rainfall and associated circulations.However,the model has a poor skill in predicting interannual variation due to its poor performance in capturing related anomalous circulations.In observation,the above-normal SC rainfall is associated with two anomalous anticyclones over the western tropical Pacific and northeastern China,respectively,with a low-pressure convergence in between.In the CFSv2,however,the anomalous circulations exhibit the patterns in response to the El Ni?o-Southern Oscillation(ENSO),demonstrating that the model overestimates the relationship between May SC rainfall and ENSO.Because of the onset of the South China Sea monsoon,the atmospheric circulation in May over SC is more complex,so the prediction for May SC rainfall is more challenging.In this study,we establish a dynamic-statistical forecast model for May SC rainfall based on the relationship between the interannual variation of rainfall and large-scale ocean-atmosphere variables in the CFSv2.The sea surface temperature anomalies(SSTAs)in the northeastern Pacific and the centraleastern equatorial Pacific,and the 500-h Pa geopotential height anomalies over western Siberia in previous April,which exert great influence on the SC rainfall in May,are chosen as predictors.Furthermore,multiple linear regression is employed between the predictors obtained from the CFSv2 and observed May SC rainfall.Both cross validation and independent test show that the hybrid model significantly improve the model’s skill in predicting the interannual variation of May SC rainfall by two months in advance.
    • Eucharia Chidinma Okoro; Francisca Nneka Okeke; Lilian Chinenyenwa Omeje
    • 摘要: The relationship between some meteorological parameters and variation of total column ozone (TCO) concentration in Nigeria is studied from 1998-2012. The results using a descriptive analysis revealed a seasonal ozone variation having the same trend in all the stations during the period of study. High variability of TCO occurred between December and March coinciding with the period of dry season and low variability of TCO was observed in August coinciding with the period of rainy season. The observed trends in all the stations show that the TCO variation in Nigeria is mostly caused by natural occurrences. Calabar and Port Harcourt stations showed a high percent of TCO variability, while Kano and Maiduguri indicated a low percentage of TCO variability. Using Spearman correlation analysis, TCO concentration has a strong negative correlation with temperature in some stations with correlation coefficient (r) (-0.8392, -0.8531, -0.7832, -8881 and -0.7902) for Calabar, Port Harcourt, Makurdi, Lagos and Ilorin respectively. Kano and Maiduguri showed a weak positive correlation coefficient (r) 0.4965 and 0.3776 respectively. Positive correlation observed in Kano and Maiduguri could be as a result of high dehydration of water vapour in these stations due to seasonal harmattan and latitudinal effects. Probably, some of the substances that could deplete ozone such as HCl, aerosol are soluble in water thereby being washed off by rain during wet season leading to maximum TCO concentration during rainy season. Consequently, the observed phenomenon is through transportation of ozone content through the influence of Brewer-Dobson circulation. Again, during wet season, there is the mechanism of low pressure and lower tropopause height phenomenon, therefore, total ozone enhancement. Interestingly, variation in TCO is part of symbolic tools for tropospheric meteorology alteration and this invariably leads to climate change.
    • Perumal Ponraj; Jai Sunder; Arun Kumar De; Rafeeque Rahman Alyethodi; Purna Chandra Mishra; Sneha Bhowmick; Debasis Bhattacharya
    • 摘要: Objective:To measure the seasonal effect on endocrinological profiles and sex behavioural profiles during rainy and dry summer seasons in male Andaman local goat in Andaman and Nicobar Islands,India.Methods:Ten adult male Andaman local goats were selected from the goat breeding farm,ICAR-Central Island Agricultural Research Institute,Port Blair,Andaman and Nicobar Islands,India.Endocrinological profiles such as follicle stimulating hormone(FSH),luteinizing hormone(LH),testosterone,thyroid stimulating hormone(TSH),triiodothyronine(T3),thyroxine(T4),cortisol and prolactin were analysed with enzyme-linked immunosorbent assay kits.Sex behavioural profiles such as libido score,mating ability score and sex behavioural score were measured during rainy and dry summer seasons in male Andaman local goat.Results:Endocrinological profiles as well as sex behavioural profiles differed significantly between rainy season and dry summer season(P<0.05).The levels of FSH,LH,testosterone,TSH,T3,and T4 were significantly higher in rainy season than in dry summer season whereas cortisol and prolactin were significantly higher in dry summer season than in rainy season(P<0.05).The ratio of T3:T4 was significantly higher in rainy season than in dry summer season.Similarly,libido score,mating ability score and sex behavioural score were significantly higher in rainy season than in dry summer season(P<0.05).Conclusions:Rainy season has significantly higher beneficial effects than summer season on reproduction and artificial breeding programmes in semi-intensive management of goat under the tropical humid island ecosystem in Andaman and Nicobar Islands.
    • Xiangzhen Kong; Yansong Xiao; Qinyi Zhi; Yahua Liao; Bin He; Hong Jian; Juan Li; Zhihui Cao; Sijun Li; Decheng Li
    • 摘要: In order to clarify the chemical properties of rainfall in typical tobacco areas in Chenzhou City, Hunan Province, and analyze its potential for soil and flue-cured tobacco planting, rainfall samples in 2020 were collected by rainfall instruments in Fangyuan Town and Aoquan Town of Guiyang County, and the chemical properties that are closely related to the quality of flue-cured tobacco were determined, such as pH, EC, total nitrogen (TN), nitrate nitrogen (), ammonium nitrogen () and ion concentrations (K+, Na+, Ca2+, Mg2+, , Al3+, , Cl−,). The results show that the pH values of rainfall samples at Fangyuan and Aoquan monitoring sites are in the range of 4.92 - 6.17 and 4.93 - 5.69 respectively, with an average of 5.27 and 5.27 respectively. The acid rain characteristic is very obvious, which is mainly dominated by . The variation of rainfall EC has seasonal characteristics. EC is low from January to September, in the range of 6.09 - 56.72 and 11.83 - 30.93 μS/cm respectively, besides, it is high from October to December, in the range of 102.63 - 174.60 and 25.05 - 86.37 μS/cm respectively. The annual deposition of TN was 22.19 and 20.76 kg/hm2/yr respectively, which were higher than that in the western regions with less human disturbance, but lower than or equal to that in the developed agricultural regions in eastern China. The proportion of in the annual deposition of TN was higher than that of at two monitoring sites, with an average of 56.51% and 38.86% respectively. Ammonia volatilization from agricultural activities contributed more to rainfall nitrogen content. The ratios of ammonium nitrogen to nitrate nitrogen deposition at two monitoring points were 1.84, 1.81, 1.86 and 1.34, 1.46, and 1.29 during the whole year, summer and autumn, winter and spring respectively. The ratio is higher in summer and autumn than in winter and spring. The weighted average equivalent concentrations of the main ions at two monitoring sites were 238.88 μeq/L and 211.21 μeq/L respectively, and the orders of the ion concentrations were slightly different. Both the concentrations of and are higher, while Mg2+, and Al3+ are lower. , and are mainly from human activities with a contribution rate between 91.90% and 99.35%. Ca2+ mainly comes from soil and ground dust, besides, Cl− and Mg2+ mainly come from marine sources and K+ mainly comes from terrestrial sources. In general, the acidic rainfall and higher concentration are beneficial to reducing the high pH value of soil in Aoquan tobacco area and improving the quality of flue-cured tobacco. Higher concentrations of and in rainfall are not conducive to the improvement of flue-cured tobacco quality, because of the high content of soil available sulfur in Chenzhou tobacco area and the characteristics of flue-cured tobacco’s preference for ammonium.
    • Chen SHENG; Bian HE; Guoxiong WU; Yimin LIU; Shaoyu ZHANG
    • 摘要: The influences of interannual surface potential vorticity forcing over the Tibetan Plateau(TP)on East Asian summer rainfall(EASR)and upper-level circulation are explored in this study.The results show that the interannual EASR and associated circulations are closely related to the surface potential vorticity negative uniform leading mode(PVNUM)over the TP.When the PVNUM is in the positive phase,more rainfall occurs in the Yangtze River valley,South Korea,Japan,and part of northern China,less rainfall occurs in southern China,and vice versa.A possible mechanism by which PVNUM affects EASR is proposed.Unstable air induced by the positive phase of PVNUM could stimulate significant upward motion and a lower-level anomalous cyclone over the TP.As a result,a dipole heating mode with anomalous cooling over the southwestern TP and anomalous heating over the southeastern TP is generated.Sensitivity experiment results regarding this dipole heating mode indicate that anomalous cooling over the southwestern TP leads to local and northeastern Asian negative height anomalies,while anomalous heating over the southeastern TP leads to local positive height anomalies.These results greatly resemble the realistic circulation pattern associated with EASR.Further analysis indicates that the anomalous water vapor transport associated with this anomalous circulation pattern is responsible for the anomalous EASR.Consequently,changes in surface potential vorticity forcing over the TP can induce changes in EASR.
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