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Geoscience Frontiers 2024 Annual Convention
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作者 Lily Wang Mudan Yin Yongqiang Yang 《Geoscience Frontiers》 2025年第3期439-442,共4页
The 2024 Geoscience Frontiers Annual Convention was held in Kuching,Malaysia,from November 18th to 22th,2024,jointly with the 2024 IAGR Annual Convention and the 21st International Conference on Gondwana to Asia.The I... The 2024 Geoscience Frontiers Annual Convention was held in Kuching,Malaysia,from November 18th to 22th,2024,jointly with the 2024 IAGR Annual Convention and the 21st International Conference on Gondwana to Asia.The IAGR Convention attracted over 150 participants from various countries,including China,India,Australia,the Republic of Korea,Japan,Malaysia,Indonesia,Thailand,Italy,Mexico,the United Kingdom,Saudi Arabia,France,and Brunei. 展开更多
关键词 Kuching International Conference Gondwana Asia Malaysia Geoscience Frontiers annual Convention geoscience frontiers annual convention IAGR annual Convention COUNTRIES China
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Phase-and Amplitude-Locking of Annual Maximum Rainfall Events in North China with the Annual Cycle of the East Asian Summer Monsoon
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作者 Wanyi SUN Congwen ZHU +2 位作者 Boqi LIU Yuhan YAN Zhiqi YAN 《Advances in Atmospheric Sciences》 2025年第8期1608-1619,共12页
The annual maximum rainfall event(AMRE)refers to the maximum consecutive five-day rainfall in a year.In North China,these events account for 15%–80%of the total summer(June–August)rainfall amount and pose a great ch... The annual maximum rainfall event(AMRE)refers to the maximum consecutive five-day rainfall in a year.In North China,these events account for 15%–80%of the total summer(June–August)rainfall amount and pose a great challenge for subseasonal-to-seasonal forecasting.Based on data analyses during 1979–2023,this study shows the interannual variability of AMRE is significantly influenced by the phase and amplitude mode of the annual cycle of the East Asian summer monsoon(EASM),characterized by two orthogonal patterns of southeasterly winds at 850 h Pa over the northwestern Pacific.The EASM phase-locked AMRE shows heavy rainfall events occurring extremely early and late in Beijing and surrounding areas,corresponding to the peak southeasterly wind anomalies in June and August.The EASM amplitude-locked AMRE exhibits extreme heavy or light rainfall over southwest areas with normal phase.Therefore,AMRE has a potential predictability on the seasonal time scale due to its phase-and amplitude-locking with the slow variation of the annual cycle of the EASM. 展开更多
关键词 annual maximum rainfall event North China PHASE-LOCKING annual cycle East Asian summer monsoon interannual variability
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Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO
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作者 Song Jiang Congwen Zhu Ning Jiang 《Atmospheric and Oceanic Science Letters》 2025年第1期12-17,共6页
The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).... The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of ENSO.Based on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual mean.The magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity analysis.Results reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO. 展开更多
关键词 annual cycle SST anomaly Antisymmetric mode ENSO
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Annual review of acupuncture research in 2024
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作者 Xue-Song Wang Hai-Ping Li +10 位作者 Guang-Ya Fan Bing-Xian Li Yuan-Bo Gao Xu-Xin Li Jing-Yi Jiao Hao Chen Guang Zuo Xi-Sheng Fan Jun Liu Jun-Cha Zhang Yan-Fen She 《Traditional Medicine Research》 2025年第11期84-107,共24页
Acupuncture has been widely recognized for its significant therapeutic effects in treating a variety of conditions,including pain management,cerebrovascular diseases,cancer-related symptoms,respiratory disorders,and n... Acupuncture has been widely recognized for its significant therapeutic effects in treating a variety of conditions,including pain management,cerebrovascular diseases,cancer-related symptoms,respiratory disorders,and neurological diseases.A large body of clinical research demonstrates the substantial benefits of acupuncture,such as improving post-stroke recovery,alleviating chronic pain,reducing chemotherapy-induced symptoms,and promoting perioperative recovery.Mechanistic studies have shown that acupuncture influences multiple physiological systems,particularly the nervous,immune,and endocrine systems,providing insights into how acupuncture modulates neuroinflammation,neurotransmitter release,and immune responses.The role of acupuncture in integrative medicine is increasingly significant,with growing recognition of its therapeutic efficacy in regions outside China,particularly in Europe and the Americas.Acupuncture is expected to continue to expand its application,offering effective non-pharmacological treatment options in various fields,thereby consolidating its position in modern healthcare.Ongoing research holds the promise that acupuncture will play a key role in managing chronic diseases and supporting overall health.The 2024 acupuncture annual review will provide a comprehensive summary of the latest clinical applications and mechanistic research in acupuncture,with the aim of elucidating the current landscape and guiding future directions in the field. 展开更多
关键词 ACUPUNCTURE annual review STROKE cerebrovascular diseases CANCER PAIN
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United for impact——ISO Annual Meeting 2025 successfully held in Rwanda
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作者 Cao Xinxin 《China Standardization》 2025年第6期72-75,共4页
The ISO Annual Meeting 2025 was successfully held in Kigali,capital of the Republic of Rwanda,on October 6-10.The event included the opening and closing ceremonies,sessions with different themes,governance meetings an... The ISO Annual Meeting 2025 was successfully held in Kigali,capital of the Republic of Rwanda,on October 6-10.The event included the opening and closing ceremonies,sessions with different themes,governance meetings and social activities.It was hosted by Rwanda Standards Board(RSB),the ISO member,marking a historic first for East Africa. 展开更多
关键词 Rwanda East Africa United Impact ISO annual meeting Kigali
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ISO Annual Meeting
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《China Standardization》 2025年第4期59-59,共1页
The ISO Annual Meeting is the world’s premier event for the international standards community.This year’s event is hosted by RSB,the national standards body of Rwanda.The theme“United for impact”calls us to harnes... The ISO Annual Meeting is the world’s premier event for the international standards community.This year’s event is hosted by RSB,the national standards body of Rwanda.The theme“United for impact”calls us to harness our collective strength in a world that needs bold,lasting change.The ISO Annual Meeting convenes global leaders and change-makers to explore how international standards can unlock progress,foster trust and drive lasting solutions to our shared challenges. 展开更多
关键词 bold change harness our collective strength international standards global leaders collective strength standards body change makers ISO annual meeting
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Study of spatiotemporal variation and annual emission of CH_(4)in Shaoxing Yangtze River Delta,China,Using a portable CH_(4) detector on the UAV
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作者 Xiaobing Pang Qianqian Shang +8 位作者 Lang Chen Songhua Sun Gaosheng Zhao Zhentao Wu Canming Zhao Youhao Lu Qianqian Sun Yan Lyu Baozhen Wang 《Journal of Environmental Sciences》 2025年第5期140-149,共10页
Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration.By 2022,the CH_(4)concentration was approximately 1.9 ppm,which... Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and concentration.By 2022,the CH_(4)concentration was approximately 1.9 ppm,which was 264%of the pre-industrial level.The spatiotemporal distribution of CH_(4)was investigated by a portable CH_(4)detector on an unmanned aerial vehicle and electric bicycles in Shaoxing,a city situated in the Yangtze River Delta,China.The vertical distribution revealed CH_(4)concentration generally decreased slowly with height.However,the inversion condition and low atmospheric boundary layer height(ABLH)leaded to the enhancement of CH_(4)with height.The highest CH_(4)concentration(2.2±0.1 ppm,n=1428)was observed in winter and the lowest(2.0±0.2 ppm,n=1530)in spring.Regarding the daily variation,CH_(4)concentration peaked at 5:00 local time(LT)and reached its lowest level at 14:00 LT,which was attributed to the daily variation of ABLH,lowest in the early morning and highest in the noon.In urban areas,CH_(4)concentrations showed higher levels near restaurants,natural gas stations and sewerage well,with a maximum value of 13.1 ppm,which was caused by CH_(4)emission and natural gas leakage from these places.The annual CH_(4)emission in Shaoxing were estimated to be approximately 69 ton/(km^(2)·year)by the mass balance approach.Compared with other cities in the world,the CH_(4)emission is in higher level which imply some control measures should be conducted to reduce CH_(4)emission in Shaoxing. 展开更多
关键词 Portable CH_(4)detector Spatiotemporal variation annual CH_(4)emission Unmanned aerial vehicle
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Annual variation of adult survival of a south-temperate House Wren population in Argentina
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作者 Gustavo J.Fernandez Mariana E.Carro Paulo E.Llambías 《Avian Research》 SCIE CSCD 2024年第2期229-237,共9页
Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environ... Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population dynamics.Despite numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the south.Here,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival estimators.We found that the probability of adult survival decreased as the abundance of breeding adults increased.This density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival. 展开更多
关键词 annual variation CJS DENSITY-DEPENDENCE SURVIVAL Troglodytes aedon bonariae
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The changes in the annual distribution of mountain runoff during the period of 1965-2018 in Hexi Corridor,Northwest China
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作者 Yan Luo ZhiXiang Lu +2 位作者 Qi Feng Meng Zhu JinBo Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第2期73-83,共11页
The annual distribution characteristics of river runoff in arid regions have significant implications for water resource stability and management.Based on the mountain runoff data from 1965 to 2018,this study examines... The annual distribution characteristics of river runoff in arid regions have significant implications for water resource stability and management.Based on the mountain runoff data from 1965 to 2018,this study examines the annual change characteristics of monthly runoff of the Shiyang River Basin,Heihe River Basin,and Shule River Basin in the Hexi Corridor,Northwest China.Many indexes are used and analyzed,including the coefficient of variance,the complete regulation coefficient,the concentration degree and concentration period,the magnitude of change,the skewness coefficient,and the kurtosis coefficient of the annual distribution curves.The results reveal the following:(1)The inhomogeneity of annual runoff distribution in the Taolai River and the rivers to the west of it,except the Shiyou River,show an increasing trend.Conversely,the inhomogeneity of the rivers to the east of the Taolai River generally show a downward trend,but the coefficient of variance value is still very high.(2)In the Shiyang River Basin,the annual distribution of the concentration period is characterized by a relatively discrete pattern.Conversely,the Heihe River Basin exhibits a relatively concentrated pattern,and the distribution pattern of the Shule River Basin is quite different.Notably,all concentration periods in the three basins have shifted backward after the 2000s.(3)The Shiyang River Basin exhibits disordered annual distribution curves of runoff in different years.In contrast,the Heihe River Basin presents a typical‘single-peak’pattern with a prominent right-skewed.The Shule River Basin has regular distribution curves,with a gradually significant‘double-peak’pattern from east to west.Overall,there has been a slight change in runoff in the Shiyang River Basin,while the Heihe River Basin and Shule River Basin have experienced significant increases in runoff.The annual distribution curves of runoff in the Liyuan River and the rivers to the east of it exhibit a gentle peak pattern,and the appearance probability of extreme runoff during the year is low.Conversely,the rivers to the west of the Liyuan River,excluding the Danghe River,display a sharp peak and thick tail pattern,indicating that the appearance probability of extreme runoff during the year is high.These findings have practical implications for the planning and management of water resources in the Hexi Corridor.Moreover,they provide a solid foundation for predicting future changes in regional water resources. 展开更多
关键词 Hexi Corridor Inland rivers Mountain runoff annual distribution characteristics of runoff
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Fragipan Horizon Changes Using Annual Ryegrass and Other Admendments
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作者 Lloyd Murdock Anastasios Karathanasis +2 位作者 Dottie Call Dana L. Dinnes Amitava Chatterjee 《Open Journal of Soil Science》 2024年第6期388-397,共10页
A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received se... A greenhouse experiment was conducted involving intact fragipan soil cores of 50 cm thickness after removing the topsoil horizons. The cores were maintained in moist condition throughout the experiment and received several treatments with various amendments for different periods ranging from 9 to 17 months. The amendments included annual ryegrass or Festulolium residues, powder limestone and various humate compounds alone or in combination with the grass residues. The results suggested a significant effect of ryegrass and Festulolium in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particularly when used in combination with certain humate materials such as Leonardite. Apparently, this is the result of the release of certain soluble organic compounds from the plant residues or the humate amendments that increase the solubility of Si and Al associated with the fragipan brittleness, thus decreasing the density of the compacted fragipan material. 展开更多
关键词 Fragipan Fragipan Horizon Fragipan Soils Changing the Fragipan annual Ryegrass Changes Fragipan Festulolium Changes Fragipan Amendments That Change the Fragipan
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Wind risk and mitigation calculator framework for determining the wind annualized risk for single- and multi-family homes to support resilient community decision-making
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作者 Ayat Al Assi Rubayet Bin Mostafiz +6 位作者 Fatemeh Orooji Arash Taghinezhad Melanie Gall Robert V.Rohli Christopher T.Emrich Carol J.Friedland Eric Johnson 《Resilient Cities and Structures》 2024年第4期21-33,共13页
Communicating risks and mitigation benefits associated with natural hazards such as wind to the general public is challenging given the location-dependency of parameters and the complexity of the problem.Web tools pla... Communicating risks and mitigation benefits associated with natural hazards such as wind to the general public is challenging given the location-dependency of parameters and the complexity of the problem.Web tools play a crucial role in educating residents,decision-makers,and stakeholders regarding potential wind hazard losses to,for example,residential buildings.However,a notable gap exists on the practical incorporation of mitigation actions within these tools.This gap hampers the collective awareness and understanding among stakeholders,communities,and citizens regarding the tangible advantages of mitigation strategies in reducing wind-related risks.Furthermore,there exists a need to elucidate the functionality and objectives of these tools in a more accessible manner.This study aims to present and outline the wind risk and mitigation calculator tool(WRMCT)within the Hazardaware platform,which is an address-based risk assessment tool.This tool,developed for 196 counties in the Gulf of Mexico coastal area,facilitates users’education of potential risks and benefits associated with mitigation strategies.WRMCT enables users to access location-specific wind risk and interactively suggests potential mitigation actions along with economic savings to support informed decisions and residential risk reduction.WRMCT intends to enhance users’ability to make informed decisions,take proactive measures in mitigating wind hazards,and contribute to the development of resilient,residential communities. 展开更多
关键词 Wind risk assessment Average annual loss(AAL) Public information technology Wind mitigation Wind loss analysis Catastrophic risk modeling Resilient communities
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Analysis on the Variations of Annual Runoff Distribution in the Weihe Basin 被引量:5
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作者 杨美临 范晓梅 《Meteorological and Environmental Research》 CAS 2010年第6期91-94,共4页
With the impact of climate change and the increasing intensity of human activities,the hydrological regime had changed,including annual runoff distribution,which was related with water resources management and ecologi... With the impact of climate change and the increasing intensity of human activities,the hydrological regime had changed,including annual runoff distribution,which was related with water resources management and ecological construction. Based on the monthly runoff data for more than 40 years of the Beidao,Xianyang,Huaxian station on Weihe Basin,the annual distribution characteristics of runoff were studied. Several indices related to attributes of uneven,concentrate degree and variation amplitude were calculated,and the results showed that there had obvious fresh and drought seasonal changes in 1990s. The annual runoff distribution had changed a lot,mainly because of runoff decrease in the wet season. The Huaxian station,which locates at the upper reaches,had a higher unevenness,concentration and relative variation rate than that of the Beidao and Xianyang station. 展开更多
关键词 Weihe Basin RUNOFF annual distribution China
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The international impact of Chinese academic journals revealed by the “Annual Report for International Citation of Chinese Academic Journals” 被引量:6
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作者 黄河清 韩健 张鲸惊 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第3期200-204,共5页
CNKI has published the "Annual Report for International Citation of Chinese Academic Journals" since 2012. In the past three years, it has provided comprehensive data on the international impact of Chinese academic ... CNKI has published the "Annual Report for International Citation of Chinese Academic Journals" since 2012. In the past three years, it has provided comprehensive data on the international impact of Chinese academic journals. Using the clout index (CI) to rank the Chinese academic journals, "the Highest International Impact Academic Journals of China" and " the Excellent International Impact Academic Journals of China" are announced every year. By introducing the rating criteria of the "Annual Report for International Citation of Chinese Academic Journals", the characteristics of high impact journals are discussed. Especially, the status of the pharmaceutical journals is discussed. We found that there are increasing numbers of Chinese journals that are included in the SCI, and some of them are high impact journals. However, journals published in Chinese are still facing difficulties to be included in SCI, even though they show higher impact than journals published in other non-English languages. The Chinese Pharmaceutical journals need to enhance their international impact, but Journals on Chinese Medicine show high impact. 展开更多
关键词 CNKI annual Report for Intemational Citation Clout index (CI) The Highest International Impact Academic Journals of China The Excellent International Impact Academic Journals of China Chinese academic journals International impact
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Annual General Meeting of the Geological Society of India
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作者 R.H.Sawkar 《Episodes》 2010年第1期67-67,共1页
The 50^(th) Annual General Meeting(AGM)of the Geological Society of India was held on 26th December 2009 at 3 pm in the Department of Geology,Mizoram University,Aizawl-796009,Mizoram.The AGM was presided over by Harsh... The 50^(th) Annual General Meeting(AGM)of the Geological Society of India was held on 26th December 2009 at 3 pm in the Department of Geology,Mizoram University,Aizawl-796009,Mizoram.The AGM was presided over by Harsh Gupta,President,Geological Society of India.R.H.Sawkar,Secretary,read the meeting notice and presented the Annual Report and audited statement of accounts for the year 2008-2009. 展开更多
关键词 secretary annual report geological society india th annual general meeting audited statement accounts annual general meeting meeting notice president
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Horizontal Distribution and Annual Variations of Fecal Coliform Bacteria in Luoyuan Bay 被引量:2
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作者 蔡雷鸣 《Marine Science Bulletin》 CAS 2010年第1期48-58,共11页
Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100... Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100 mL) to 540 cfu/100 mL in Luoyuan Bay. Values of FCB during August to October were significantly higher than those during January to April during three year period. Monthly changes of FCB values at each year period were mainly due to monthly precipitation. In addition, compared with FCB values in difference sample sites, values of FCB in Bay-heed were significantly higher than those in middle of bay and Bay-mouth, Luoyuan Bay. However, values of FCB in Bay-mouth were significantly less than those in middle of bay. The ratios to the par of FCB in 2003, 2004, and 2005 years were 100%, 98.0%, and 97.9%, respectively. Therefore, we considered that the pollution of FCB of surface marine water in Luoyuan Bay was not serious. 展开更多
关键词 Luoyuan Bay fecal coliform bacteria horizontal distribution annual variations
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Variations in the annual cycle of the East Asian monsoon and its phase-induced interseasonal rainfall anomalies in China 被引量:5
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作者 JIANG Song ZHU Congwen JIANG Ning 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期316-322,共7页
The East Asian monsoon(EAM)exhibits a robust annual cycle with significant interannual variability.Here,the authors find that the EAM annual cycle can be decomposed into the equinoctial and solstitial modes in the com... The East Asian monsoon(EAM)exhibits a robust annual cycle with significant interannual variability.Here,the authors find that the EAM annual cycle can be decomposed into the equinoctial and solstitial modes in the combined sea level pressure,850-hPa low-level wind,and rainfall fields.The solstitial mode shows a zonal pressure contrast between the continental thermal low and the western Pacific subtropical high,reaching its peak in July and dominating the East Asian summer monsoon.The equinoctial mode shows an approximate zonal contrast between the low-level cyclone over the east of the Tibetan Plateau and the western Pacific anticyclone over the east of the Philippines.It prevails during the spring rainy season in South China and reaches its peak in April.The interannual variations of the lead–lag phase of the two modes may result in the negative correlation of rainfall anomalies in North China between spring and fall and in South China between winter and summer,which provides a potential basis for the across-seasonal prediction of rainfall.The warm phase of ENSO in winter could give rise to the reverse interseasonal rainfall anomalies in South China,while the SST anomaly in the Northwest Pacific Ocean may regulate the rainfall anomaly in North China. 展开更多
关键词 annual cycle East Asian monsoon interannual variability
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Quantification of relationship between annual daily maximum temperature and annual daily maximum rainfall in South Australia
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作者 YE Qianping AHAMMED Faisal 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期286-293,共8页
The empirical relationship between annual daily maximum temperature(ADMT)and annual daily maximum rainfall(ADMR)was investigated.The data were collected from four weather stations located in Adelaide,South Australia,f... The empirical relationship between annual daily maximum temperature(ADMT)and annual daily maximum rainfall(ADMR)was investigated.The data were collected from four weather stations located in Adelaide,South Australia,from 1988 to 2017.Due to the influence of sea surface temperature on rainfall and temperature,the distance from the weather station to the sea was considered in the selection of weather stations.Two weather stations near the sea and two inland weather stations were selected.Three non-parametric statistical tests(Kruskal–Wallis,Mann–Whitney,and correlation)were applied to perform statistical analysis on the ADMT and ADMR data.It was revealed that the temperature and rainfall in South Australia varies according to weather station location.The distance from the sea to the weather station was found to have limited influence on temperature and rainfall.Meanwhile,with the 0.05 level of significance,the association between ADMT and ADMR near sea stations is not as significant as the association between the two inland weather stations.It is relatively unrealistic to use ADMR to predict ADMT,or vice versa,since their correlation is not statistically significant(Spearman’s rank correlation coefficient:−0.106). 展开更多
关键词 annual daily maximum rainfall annual daily maximum temperature kruskal–Wallis Mann–Whitney correlation
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Annual Runoff and Sediment in Duhok Reservoir Watershed Using SWAT and WEPP Models
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作者 Mohammad E. Mohammad Nadhir Al-Ansari Sven Knutsson 《Engineering(科研)》 2016年第7期410-422,共14页
Estimation of runoff volume and sediment load is the main problem that affects the performance of dams due to the reduction in the storage capacity of their reservoirs and their effect on dam efficiency and operation ... Estimation of runoff volume and sediment load is the main problem that affects the performance of dams due to the reduction in the storage capacity of their reservoirs and their effect on dam efficiency and operation schedule. The simulation models can be considered for this purpose if the continuous field measurements are not available. Soil and Water Assessment Tool (SWAT) and Water Erosion Prediction Project (WEPP) models were applied to estimate the annual runoff volume and sediment load for Duhok Dam Reservoir in north of Duhok/Iraq for the period 1988-2011. The estimated annual runoff volume varied from 2.3 to 34.7 MCM for considered period. Those values were affected by rainfall depth, intensity and runoff coefficient. The resultant annual runoff coefficient for the studied area ranged from 0.05 to 0.35 (average was 0.18) causing an average runoff volume of about 14 MCM. The results of sediment routing indicated that the values of sediment yields varied from 50 to 1400 t/km2/year depending on sub basin properties. The average annual sediment load from the whole watershed is about 120 × 10<sup>3</sup> ton. The estimated total sediment arrived to Duhok Reservoir for the considered period 1988-2011 was about 2.9 × 10<sup>6</sup> ton. The results indicate that both models gave reasonable results in comparison with measured values. Based on statistical criteria, the results of both models are close to gather. 展开更多
关键词 annual Runoff annual Sediments Duhok Dam SWAT Model WEPP Model
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The Role of Changes in the Annual Cycle in Earlier Onset of Climatic Spring in Northern China 被引量:14
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作者 钱诚 符淙斌 严中伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第2期284-296,共13页
Climatic changes in the onset of spring in northern China associated with changes in the annual cycle and with a recent warming trend were quantified using a recently developed adaptive data analysis tool, the Ensembl... Climatic changes in the onset of spring in northern China associated with changes in the annual cycle and with a recent warming trend were quantified using a recently developed adaptive data analysis tool, the Ensemble Empirical Mode Decomposition. The study was based on a homogenized daily surface air temperature (SAT) dataset for the period 1955–2003. The annual cycle here is referred to as a refined modulated annual cycle (MAC). The results show that spring at Beijing has arrived significantly earlier by about 2.98 d (10 yr)-1, of which about 1.85 d (10 yr)-1 is due to changes in the annual cycle and 1.13 d (10 yr)-1 due to the long-term warming trend. Variations in the MAC component explain about 92.5% of the total variance in the Beijing daily SAT series and could cause as much as a 20-day shift in the onset of spring from one year to another. The onset of spring has been advancing all over northern China, but more significant in the east than in the west part of the region. These differences are somehow unexplainable by the zonal pattern of the warming trend over the whole region, but can be explained by opposite changes in the spring phase of the MAC, i.e. advancing in the east while delaying in the west. In the east of northern China, the change in the spring phase of MAC explains 40%–60% of the spring onset trend and is attributable to a weakening Asian winter monsoon. The average sea level pressure in Siberia (55°–80°N, 50°–110°E), an index of the strength of the winter monsoon, could serve as a potential short-term predictor for the onset of spring in the east of northern China. 展开更多
关键词 spring onset Ensemble Empirical Mode Decomposition modulated annual cycle Asian winter monsoon global warming
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On Multi-Timescale Variability of Temperature in China in Modulated Annual Cycle Reference Frame 被引量:16
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作者 钱诚 Zhaohua WU +1 位作者 符淙斌 周天军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1169-1182,共14页
The traditional anomaly (TA) reference frame and its corresponding anomaly for a given data span changes with the extension of data length. In this study, the modulated annual cycle (MAC), instead of the widely us... The traditional anomaly (TA) reference frame and its corresponding anomaly for a given data span changes with the extension of data length. In this study, the modulated annual cycle (MAC), instead of the widely used climatological mean annual cycle, is used as an alternative reference frame for computing climate anomalies to study the multi-timescale variability of surface air temperature (SAT) in China based on homogenized daily data from 1952 to 2004. The Ensemble Empirical Mode Decomposition (EEMD) method is used to separate daily SAT into a high frequency component, a MAC component, an interannual component, and a decadal-to-trend component. The results show that the EEMD method can reflect historical events reasonably well, indicating its adaptive and temporally local characteristics. It is shown that MAC is a temporally local reference frame and will not be altered over a particular time span by an exten-sion of data length, thereby making it easier for physical interpretation. In the MAC reference frame, the low frequency component is found more suitable for studying the interannual to longer timescale variability (ILV) than a 13-month window running mean, which does not exclude the annual cycle. It is also better than other traditional versions (annual or summer or winter mean) of ILV, which contains a portion of the annual cycle. The analysis reveals that the variability of the annual cycle could be as large as the magnitude of interannual variability. The possible physical causes of different timescale variability of SAT in China are further discussed. 展开更多
关键词 modulated annual cycle the Ensemble Empirical Mode Decomposition climate anomaly climate normal variability of surface air temperature in China
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