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Science China Earth Sciences 2021年第5期64卷 716-727页

作者： Haodong ZHANG Yinshuang AI Yumei HE Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100049China University of Chinese Academy of Sciences Beijing 100101China

Quantifying the density contrasts of the Earth’s inner core boundary(ICB)is crucial to understand core-mantle coupling and the generation of the *** PKiKP/PcP amplitude ratio is commonly used to obtain the density contrast at the ICB,but its applications are limited by scattered observed *** this study,we selected the PKiKP and PcP phases reflected at the same region of inner-core and core-mantle boundaries beneath northeast asia from different earthquakes for the first time,and the observations suggested that the PKiKP/PcP amplitude ratio is widely *** also compared the PKiKP and PcP amplitudes,which demonstrated that the scatter cannot be attributed only to ICB anomalies but might also arise from raypath differences and heterogeneities throughout the crust and *** fitting the observed PKiKP/PcP amplitude ratio,we obtained a density contrast of approximately 0.65 g cm^(-3) and a compressional velocity contrast of approximately 0.87 km s^(-1) at the ICB beneath northeast *** larger contrast values indicate the possible occurrence of local crystallization occurring at the inner core surface.

关键词： northeast asia Inner core boundary PKiKP/PcP amplitude ratio Density contrast

ECONOMIC EXCHANGES AND SECTORAL AND INTER CITY COOPERATION IN northeast asia

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Chinese Geographical Science 2002年第2期12卷 97-106页

作者： LIWen－yan PANGXiao－min InstituteofGeographicSciencesandNaturalResourcesResearch theChineseAcademyofSciencesBeijing100101P.R.China InstituteofGeographicSciencesandNaturalResourcesResearch theChineseAcademyofSciencesBeijin

northeast asia with China, Japan and South Korea as the main components has drawn more and more attention worldwide. Many scholars have researched on the prospect of some alternatives of regional economic integration in northeast asia and/or Yellow Sea Rim as its core area. In this paper the authors start with an introduction of the major arguments embracing Yellow Sea Rim regionalism, and attempt to identify the dynamics challenging the proposed approaches of sub regionalism of northeast asia. The paper firstly gives a brief review on the update development of bilateral economic exchanges, mainly Sino Japanese and Sino South Korean trades and direct investments with related contemporary issues. When the changing pattern of economic interactions is analyzed, special concerns are given to the possibility to realize the supposed potential of regional economic cooperation mainly based on economic complementarity among the related regions of China, North Korea, South Korea, and Japan. The authors then made their major efforts on putting forward possible approaches of multilateral cooperation of three countries in the near future, that is, deepened cooperation in selected sectors of industry and transportation and coordinated development among major cities. The authors stress that the development of sub regional sectoral cooperation and the formation of interactive network of city regions via social and economic interactions at local level are significant to the future regional integrated development in northeast asia.

关键词： northeast asia economic exchange cooperation

Variation in Summer Surface Air Temperature over northeast asia and Its Associated Circulation Anomalies

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Advances in Atmospheric Sciences 2016年第1期33卷 1-9页

作者： Wei CHEN Xiaowei HONG Riyu LU Aifen JIN Shizhu JIN Jae-Cheol NAM Jin-Ho SHIN Tae-Young GOO Baek-Jo KIM State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 University of Chinese Academy of Sciences Beijing 100049 Department of Geography Yanbian University Yanji 133002 National Institute of Meteorological Research Korea Meteorological Administration deju Korea

This study investigates the interannual variation of summer surface air temperature over northeast asia（NEA） and its associated circulation *** leading modes for the temperature variability over NEA are obtained by EOF *** first EOF mode is characterized by a homogeneous temperature anomaly over NEA and therefore is called the NEA *** anomaly extends from southeast of Lake Baikal to Japan,with a central area in northeast *** second EOF mode is characterized by a seesaw pattern,showing a contrasting distribution between East asia（specifically including the Changbai Mountains in northeast China,Korea,and Japan） and north of this *** mode is named the East asia（EA） *** modes contribute equivalently to the temperature variability in *** two leading modes are associated with different circulation anomalies.A warm NEA mode is associated with a positive geopotential height anomaly over NEA and thus a weakened upper-tropospheric westerly *** the other hand,a warm EA mode is related to a positive height anomaly over EA and a northward displaced *** addition,the NEA mode tends to be related to the Eurasian teleconnection pattern,while the EA mode is associated with the East asia-Pacific/PacificJapan pattern.

关键词： surface air temperature northeast asia East asia circulation anomaly interannual variability

Abrupt Summer Warming and Changes in Temperature Extremes over northeast asia Since the Mid-1990s: Drivers and Physical Processes

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Advances in Atmospheric Sciences 2016年第9期33卷 1005-1023页

作者： Buwen DONG Rowan T.SUTTON Wei CHEN Xiaodong LIU Riyu LU Ying SUN National Centre for Atmospheric Science Department of Meteorology University of Reading State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Institute of Earth Environment Chinese Academy of Sciences National Climate Center China Meteorological Administration

This study investigated the drivers and physical processes for the abrupt decadal summer surface warming and increases in hot temperature extremes that occurred over northeast asia in the mid-1990s. Observations indicate an abrupt increase in summer mean surface air temperature （SAT） over northeast asia since the mid-1990s. Accompanying this abrupt surface wanning, significant changes in some temperature extremes, characterized by increases in summer mean daily maximum temperature （Tmax）, daily minimum temperature （Train）, annual hottest day temperature （TXx）, and annual warmest night temperature （TNx） were observed. There were also increases in the frequency of summer days （SU） and tropical nights （TR）. Atmospheric general circulation model experiments forced by changes in sea surface temperature （SST）/sea ice extent （SIE）, anthropogenic greenhouse gas （GHG） concentrations, and anthropogenic aerosol （AA） forcing, relative to the period 1964- 93, reproduced the general patterns of observed summer mean SAT changes and associated changes in temperature extremes, although the abrupt decrease in precipitation since the mid-1990s was not simulated. Additional model experiments with different forcings indicated that changes in SST/SIE explained 76% of the area-averaged summer mean surface warming signal over northeast asia, while the direct impact of changes in GHG and AA explained the remaining 24% of the surface warming signal. Analysis of physical processes indicated that the direct impact of the changes in AA （through aerosol- radiation and aerosol-cloud interactions）, mainly related to the reduction of AA precursor emissions over Europe, played a dominant role in the increase in TXx and a similarly important role as SST/SIE changes in the increase in the frequency of SU over northeast asia via AA-induced coupled atmosphere-land surface and cloud feedbacks, rather than through a direct impact of AA changes on cloud condensation nuclei. The modelling results also imply

关键词： surface warming temperature extremes global climate model anthropogenic greenhouse gas anthropogenic aerosol SST/SIE northeast asia mid-1990s

Impacts of Land Cover Changes on Ecosystem Carbon Stocks Over the Transboundary Tumen River Basin in northeast asia

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Chinese Geographical Science 2018年第6期28卷 973-985页

作者： XIANG Hengxing JIA Mingming WANG Zongming LI Lin MAO Dehua ZHANG Da CUI Guishan ZHU Weihong Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China College of Science Yanbian University Yanji 133002 China Department of Earth Sciences Indiana University-Purdue University Indianapolis 420 USA Key Laboratory of Natural Resources of Changbai Mountain & Functional Molecules ( Yanbian University) Ministry of Education Yanji 133002 China Jilin Province Joint Key Laboratory of Changbai Mountain Wetland &Ecological Yanji 133002 China

Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and envi- ronmental protection, particularly in the transboundary region that has undergone marked changes. This study aimed to examine the impacts of land cover changes on ecosystem carbon stocks in the transboundary Tureen River Basin （TTRB）. We extracted the spatial information from Landsat Thematic Imager （TM） and Operational Land Imager （OLI） images for the years 1990 and 2015 and obtained convincing estimates of terrestrial biomass and soil carbon stocks with the INVEST model. The results showed that forestland, cropland and built-up land increased by 57.5, 429.7 and 128.9 km2, respectively, while grassland, wetland and barren land declined by 24.9, 548.0 and 43.0 km2, respectively in the TTRB from 1990 to 2015. The total carbon stocks encompassing aboveground, belowground, soil and litter layer carbon storage pools have declined from 831.48 Tg C in 1990 to 831.42 Tg C in 2015 due to land cover changes. In detail, the carbon stocks de- creased by 3.13 Tg C and 0.44 Tg C in Democratic People＇s Republic of Korea （North Korea） and Russia, respectively, while increased by 3.51 Tg C in China. Furthermore, economic development, and national policy accounted for most land cover changes in the TTRB. Our results imply that effective wetland and forestland protection policies among China, North Korea, and Russia are much needed for protecting the natural resources, promoting local ecosystem services and regional sustainable development in the transnational area.

关键词： land cover change carbon stock INVEST model Transboundary Tumen River Basin northeast asia

Formation Mechanism for the Anomalous Anticyclonic Circulation over northeast asia and the Japan Sea in Boreal Winter 1997/98 and the Spring of 1998

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Journal of Ocean University of China 2013年第2期12卷 312-317页

作者： WANG Hai LIU Qinyu ZHENG Jian Physical Oceanography Laboratory Key Laboratory of Ocean-Atmosphere Interaction and Climate in Universities of ShandongOcean University of China

A robust anomalous anticyclonic circulation (AAC) was observed over northeast asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the background of the vertically sheared winter monsoonal flow, anomalous rainfall in the tropical Indo-Western Pacific warm pool excited a wave train towards East asia in the upper troposphere during boreal winter of 1997/98. The AAC over northeast asia and the Japan Sea is part of the wave train of equivalent barotropic structure. The AAC over the Japan Sea persisted from winter to spring and even intensified in spring 1998. The diagnostic calculations show that the vorticity and temperature fluxes by synoptic eddies are an important mechanism for the AAC over the Japan Sea in spring 1998.

关键词： anomalous anticyclonic circulation northeast asia Japan Sea wave train synoptic eddy

A Decadal Shift of Summer Surface Air Temperature over northeast asia around the Mid-1990s

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Advances in Atmospheric Sciences 2014年第4期31卷 735-742页

作者： CHEN Wei LU Riyu State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Division of Earth Environmental System Pusan National University

This study identifies a decadal shift of summer surface air temperature （SAT） over northeast asia,including southeastern parts of Russia,Mongolia and northern China,around the *** results suggest that the SAT over the northeast asia experienced a significant warming after 1994 relative to that before *** decadal shift also extends to northern China,and leads to a warmer summer over northeast China and North China after the *** decadal warming over northeast asia is found to concur with the enhancement of South China rainfall around the *** the one hand,both the northeast asian SAT and South China rainfall exhibit this mid-1990s decadal shift only in summer,but not in other *** the other hand,both the northeast asian SAT and South China rainfall exhibit this mid-1990s decadal shift not only in the summer seasonal mean,but also in each month of summer （June,July and August）.Furthermore,the decadal warming is found to result from an anticyclonic anomaly over northeast asia,which can be interpreted as the response to the increased precipitation over South China,according to previous numerical ***,we conclude that the warming shift of summer northeast asian SAT around the mid-1990s was a remote response to the increased precipitation over South China.

关键词： surface air temperature northeast asia decadal shift mid-1990s South China rainfall

Synergistic Impacts of the Atlantic and Pacific Oceans on Interdecadal Variations of Summer Rainfall in northeast asia

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Journal of Meteorological Research 2021年第5期35卷 844-856页

作者： Dong SI Dabang JIANG Yihui DING Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044 College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049 National Climate Center China Meteorological AdministrationBeijing 100081

This study presents a comprehensive analysis of the synergistic impacts of the Atlantic multidecadal oscillation(AMO)and Pacific decadal oscillation(PDO)on the interdecadal variations of summer rainfall in northeast *** the construction of four probable scenarios under various combinations of the AMO and PDO phases,it is found that when the AMO and PDO are out of phase,both of them induce a strong or weak East asian summer monsoon and a low or high pressure system over northeast asia through atmospheric teleconnection,which results in significant wet or dry conditions over the whole of northeast asia through the effects of *** contrast,when the AMO and PDO are in-phase,they induce moderate and regional wet or dry conditions in northeast asia,and only a slightly strong or weak East asian summer monsoon through the effects of *** the mid-1960 s-1990 s,a period of drought first began in northeast asia under a negative AMO and negative PDO in the mid-1960 s,which then increased in severity under a negative AMO and positive PDO in the 1980 s,before finally coming to an end under a positive AMO and negative PDO in the late 1990 *** interdecadal predictability of summer rainfall in northeast asia may reside in the interdecadal behavior of the North Atlantic and Pacific Oceans.

关键词： Atlantic multidecadal oscillation Pacific decadal oscillation synergistic impacts northeast asia summer rainfall

The Unprecedented Extreme Anticyclonic Anomaly over northeast asia in July 2021 and Its Climatic Impacts

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Advances in Atmospheric Sciences 2024年第4期41卷 608-618页

作者： Xingyan ZHOU Riyu LU Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

This study investigates the evolution of an extreme anomalous anticyclone(AA)event over northeast asia,which was one of the dominant circulation systems responsible for the catastrophic extreme precipitation event in July 2021 in Henan,and further explores the significant impact of this AA on surface temperatures beneath *** results indicate that this AA event over northeast asia was unprecedented in terms of intensity and *** AA was very persistent and extremely strong for 10 consecutive days from 13 to 22 July *** long-lived and unprecedented AA led to the persistence of warmer surface temperatures beyond the temporal span of the pronounced 500-hPa anticyclonic signature as the surface air temperatures over land in northeast asia remained extremely warm through 29 July ***,the sea surface temperatures in the Sea of Japan/East Sea were extremely high for 30 consecutive days from 13 July to 11 August 2021,persisting well after the weakening or departure of this *** results emphasize the extreme nature of this AA over northeast asia in July 2021 and its role in multiple extreme climate events,even over remote ***,possible reasons for this long-lasting AA are explored,and it is suggested to be a byproduct of a teleconnection pattern over extratropical Eurasia during the first half of its life cycle,and of the Pacific-Japan teleconnection pattern during the latter half.

关键词： anomalous anticyclone northeast asia surface air temperatures sea surface temperatures

Influences of tropical circulation and sea surface temperature anomalies on extreme heat over northeast asia in the midsummer of 2018

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Atmospheric and Oceanic Science Letters 2019年第4期12卷 238-245页

作者： CHEN Ruidan WEN Zhiping LU Riyu Center for Monsoon and Environment Research/Guangdong Province Key Labor atory for Climate Change and Natural Disaster Studies/School of Atmospheric Sciences Sun Yat-sen UniversityGuangzhouChina Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityChina State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of the Chinese Academy of SciencesBeijingChinaeJiangsu Collaborative Innovation Center for Climate ChangeNanjingChina

A destructive extreme heat attacked northeast asia(NEA)in the midsummer of 2018,characterized by the average midsummer Tmax(daily maximum air temperature at 2 m)ranking first during the study *** current study indicates that the cyclonic anomaly over the western North Pacific(WNP)was an important cause,which presents an anomaly of two standard *** cyclonic anomaly over the WNP was accompanied by anomalous convection,which favored descending and anticyclonic anomalies over NEA through a local meridional *** anticyclonic anomaly over NEA corresponds to the northwestward extension of the WNP subtropical high and facilitated the occurrence of extreme *** tropical sea surface temperature anomaly(SSTA)presents a La Ni?a decaying episode,but the SSTA over the tropical Pacific and North Indian Ocean was weak in the *** contrast,the southeastern tropical Indian Ocean(SETIO)was obviously cool,which was the coolest after *** SETIO cooling triggered a low-level southeasterly anomaly,which turned into a southwesterly after crossing the equator,due to the Coriolis *** southwesterly anomaly extended eastwards and favored the cyclonic anomaly over the ***,the circulation anomalies over the SETIO and WNP were connected via a local meridional cell,with the ascending branch over the ***,the above mechanism also operates for the climate statistics,verifying the robust in?uence of the SETIO *** the consistency of the SETIO SSTA,it could be a potential predictor for the climate over the WNP and NEA.

关键词： Extreme heat northeast asia tropical circulation southeastern tropical Indian Ocean