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Acta Oceanologica Sinica 2000年第3期19卷 131-138页

作者：王汝建 Andrea Abelmann Laboratory of Marine Geology Ministry of Education Tongji University Shanghai 200092China Alfred Wegener Institute for Polar and Marine Research 27515 BremerhavenGermany

abrupt changes in radiolarian composition are discovered over the last 600 and 120 ka B. P. based on quantitative analyses of radiolarians in ~ 17957 - 2 of the southern South China Sea. The distinct changes at 600 ka B. P. could correspond to the onset of the 100 ka cycle during the glacial and interglacial periods. This abrupt change in the 100 ka cyclicity at 600 ka B. P. occurred also in the magnetic susceptibility signal that is obtained from and paleosol sequences of the China Loss Plateau. The larger amplitude and stronger cyclicity in the susceptibility signal after 600 ka B. P. reflect the prominent change in the intensity of the monsoon, induced by an enhancement of the momsoon circula- tion. Stronger seasonality during the glacial period in the South China Sea, resulted from strengthening of winter monsoon, might lead to the changes in the radiolarian composition at 600 and 120 ka B. P. It can be suggested that only species adapted to a broader temperature range might have been able to live in this environment. Therefore, the abrupt changes in radiolarian composition at 600 and 120 ka B. P. could be attributed to the stronger so differences between summer and winter that were caused by the striking change in the intensity of the monsoon circulation.

关键词： Radiolarian fauna abrupt changes 600 and 120 ka B. P. East Asian monsoon South China Sea

Spatio-temporal analysis of the melt onset dates over Arctic sea ice from 1979 to 2017

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Acta Oceanologica Sinica 2022年第4期41卷 146-156页

作者： Shuang Liang Jiangyuan Zeng Zhen Li Dejing Qiao Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Surveying and Geo-Informatics North China University of Water Resources and Electric PowerZhengzhou 450045China

The melt onset dates(MOD)over Arctic sea ice plays an important role in the seasonal cycle of sea ice surface properties,which impacts Arctic surface solar radiation absorbed by the ice-ocean *** interannual variations in MOD is valuable for understanding climate *** this study,we investigated the spatio-temporal variability of MOD over Arctic sea ice and 14 Arctic sub-regions in the period of 1979 to 2017 from passive microwave satellite data.A set of mathematical and statistical methods,including the Sen’s slope and Mann-Kendall mutation tests,were used to comprehensively assess the variation trend and abrupt points of MOD during the past 39 years for different Arctic ***,the correlation between Arctic Oscillation(AO)and MOD was *** results indicate that:(1)all Arctic sub-regions show a trend toward earlier MOD except the Bering Sea and *** *** East Siberian Sea exhibits a significantly earlier trend,with the highest rate of-9.45 d/decade;(2)the temporal variability and statistical significance of MOD trend exhibit large interannual differences with different time windows for most regions in the Arctic;(3)during the past 39 years,the MOD changed abruptly in different years for different sub-regions;(4)the seasonal AO has more influence on MOD than monthly *** findings in this study can improve our knowledge of MOD changes and are beneficial for further Arctic climate change study.

关键词： Arctic sea ice melt onset dates spatio-temporal analysis abrupt changes Arctic Oscillation

Multi-scale variability of water discharge and sediment load into the Bohai Sea from 1950 to 2011

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Journal of Geographical Sciences 2015年第1期25卷 85-100页

作者： REN Huiru LI Guosheng CUI Linlin HE Lei Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

This paper examines the changes in the time series of water discharge and sediment load of the Yellow River into the Bohai Sea. To determine the characteristics of abrupt changes and multi-scale periods of water discharge and sediment load, data from Lijin station were analyzed, and the resonance periods were then calculated. The Mann-Kendall test, order clustering, power-spectrum, and wavelet analysis were used to observe water discharge and sediment load into the sea over the last 62 years. The most significant abrupt change in water discharge into the sea occurred in 1985, and an abrupt change in sediment load happened in the same year. Significant decreases of 64.6% and 73.8% were observed in water discharge and sediment load, respectively, before 1985. More significant abrupt changes in water discharge and sediment load were observed in 1968 and 1996. The characteristics of water discharge and sediment load into the Bohai Sea show periodic oscillation at inter-annual and decadal scales. The main periods of water discharge are 9.14 years and 3.05 years, whereas the main periods of sediment load are 10.67 years, 4.27 years, and 2.78 years. The significant resonance periods between water discharge and sediment load are observed at the following temporal scales： 2.86 years, 4.44 years, and 13.33 years. Water discharge and sediment load started to decrease after 1970 and has decreased significantly since 1985 for several reasons. Firstly, the precipitation of the Yellow River drainage area has reduced since 1970. Secondly, large-scale human activities, such as the building of reservoirs and floodgates, have increased. Thirdly, water and soil conservation have taken effect since 1985.

关键词： water discharge sediment load resonance periods abrupt changes multi-scale periods Yellow River Bohai Sea

abrupt Flood–Drought Alternation in Southern China during Summer 2019

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Journal of Meteorological Research 2021年第6期35卷 998-1011页

作者： Yuan YUAN Hui GAO Ting DING National Climate Center China Meteorological AdministrationBeijing 100081

We investigated the abrupt alternation from flood to drought in southern China during summer 2019 using multiple *** anomalies of precipitation occurred in southern China in the summer of 2019 and the daily precipitation in the south of the middle and lower reaches of the Yangtze River valley showed an abrupt change from flood to drought conditions around *** highest precipitation in 39 yr was recorded between 1 June and 14 July *** circulation systems affecting this high precipitation included a persistent deepened East Asian trough,the southward location of the western Pacific subtropical high,an intensified East Asian subtropical jet,an anomalous low-level cyclone from southern Japan to southern China,and extremely strong positive vorticity over the Jiangnan *** different atmospheric circulation anomalies from 15 July to 31 August caused continuously high temperatures,below-normal precipitation,and severe drought in Jiangnan *** investigations showed that the sudden change in atmospheric circulation around mid-July started in the mid and lower troposphere and was influenced by the northward track of Tropical Cyclone Danas in the northwestern Pacific.

关键词： abrupt changes summer precipitation East Asian trough western Pacific subtropical high tropical cyclone

Variation characteristics of evaporation in the Gulang River Basin during 1959−2013

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Research in Cold and Arid Regions 2020年第4期12卷 252-260页

作者： TingTing Wang JianGuo Li ZongXing Li School of Economics and Management Lanzhou Jiaotong UniversityLanzhouGansu 730070China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Ecohydrology of Inland River Basin Chinese Academy of SciencesLanzhouGansu 730000China

Based on monthly evaporation of two meteorological stations in the Gulang River Basin of China,the inter-annual variation of evaporation during 1959−2013 were analyzed using Mann-Kendall and wavelet *** results demonstrated that the annual evaporation show a fluctuating increase over the past 50 years approximately,with an average increase rate of 4.26 mm per *** overall trend was decrease−increase−*** to the cumulative anomaly curve,the turning point of the annual evaporation occurred in 1979,in which the evaporation increased in the early stage and decreased in the later ***,the seasonal variation of the evaporation shows that it decreased in Spring and Autumn,and increased in Summer and Winter,especially obvious for the *** evaporation abruptly changed in Spring and Summer in 2008 and in Winter in *** addition,all evaporation increased after the ***,the evaporation in Autumn abruptly changed in 1986 and 1999,which show a trend of *** analysis shows that evaporation in Summer and wet season would decrease in the next few years,and in the other seasons would *** on the aforementioned analysis,it can be concluded that increased evaporation is mainly induced by increase of evaporation in dry season,especially in Winter,and this trend to be continued in the future for the Gulang River Basin.

关键词： Gulang River Basin evaporation abrupt changes wavelet analysis