检索结果-南通市图书馆

decadal change of the Linkage between Sea Ice over the Barents–Kara Seas in November– December and the Stratospheric Polar Vortex in Subsequent January

引用

Journal of Meteorological Research 2022年第4期36卷 601-617页

作者： Haibo ZHOU Ke FAN Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 School of Atmospheric Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082 University of Chinese Academy of Sciences Beijing 100049

The linkage between the sea ice concentration(SIC)over the Barents–Kara Seas in November–December(SIC_BKS_ND)and the stratospheric polar vortex(SPV)in subsequent January(SPV_Jan)is investigated.It is found that SIC_BKS_ND is positively(negatively)correlated with SPV_Jan for the period 1979–1995(1996–2009).Further analyses reveal that,during 1979–1995(1996–2009),SIC_BKS_ND is relatively higher(lower),accompanied by smaller(larger)interannual variability with its center shifting northwest(southeast).Meanwhile,the polar front jet waveguide is relatively stronger(weaker).The simultaneous anomalous eastward-propagating Rossby waves excited by anomalously low SIC_BKS_ND are stronger(weaker),which results in the stronger(weaker)negative–positive–negative wave-train structure of geopotential height anomalies over Eurasia,with the location of these anomalous height centers shifting remarkably westward(eastward).Such changes tend to enhance(suppress)vertically propagating tropospheric planetary waves into the lower stratosphere at high-latitude via constructive(destructive)interference of anomalous tropospheric wave-train structure with the climatological planetary waves,subsequently weakening(strengthening)SPV_Jan.However,in conjunction with anomalously high SIC_BKS_ND,the interference of the tropospheric wave-train structure anomalies and their climatologies shows an opposite distribution to that of low SIC_BKS_ND anomalies,which leads to a strong(weak)SPV_Jan anomaly during 1979–1995(1996–2009).

关键词： decadal change sea ice over the Barents–Kara Seas stratospheric polar vortex tropospheric wave-train structure planetary waves

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

decadal change in the Influence of the Western North Pacific Subtropical High on Summer Rainfall over the Yangtze River Basin in the Late 1970s

引用

Advances in Atmospheric Sciences 2021年第11期38卷 1823-1834页

作者： Xinyu LI Riyu LU Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210098China 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 the Chinese Academy of SciencesBeijing 100049China College of Oceanography Hohai UniversityNanjing 210098China

It is well known that on the interannual timescale,the westward extension of the western North Pacific subtropical high(WNPSH)results in enhanced rainfall over the Yangtze River basin(YRB)in summer,and vice versa.This study identifies that this correspondence experiences a decadal change in the late 1970s.That is,the WNPSH significantly affects YRB precipitation(YRBP)after the late 1970s(P2)but not before the late 1970s(P1).It is found that enhanced interannual variability of the WNPSH favors its effect on YRB rainfall in P2.On the other hand,after removing the strong WNPSH cases in P2 and making the WNPSH variability equivalent to that in P1,the WNPSH can still significantly affect YRB rainfall,suggesting that the WNPSH variability is not the only factor that affects the WNPSH-YRBP relationship.Further results indicate that the change in basic state of thermal conditions in the tropical WNP provides a favorable background for the enhanced WNPSH-YRBP relationship.In P2,the lower-tropospheric atmosphere in the tropical WNP gets warmer and wetter,and thus the meridional gradient of climatological equivalent potential temperature over the YRB is enhanced.As a result,the WNPSH-related circulation anomalies can more effectively induce YRB rainfall anomalies through affecting the meridional gradient of equivalent potential temperature over the YRB.

关键词： Yangtze River basin western North Pacific subtropical high rainfall interannual relationship decadal change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic-Analogue Correction of the decadal change of East Asian Summer Precipitation in the Late 1990s

引用

Journal of Meteorological Research 2016年第3期30卷 341-355页

作者：龚志强李尚峰胡泊沈柏竹封国林 Laboratory for Climate Studies and Climate Prediction National Climate CenterChina Meteorological Administration Laboratory of Research for Middle-High Latitude Circulation and East Asian Monsoon Jilin Meteorological Science Institute Department of Physics Yangzhou University

This paper systematically evaluates the deviations that appear in the hindcasts of the East Asian summer precipitation（EASP） decadal change in the late 1990 s in two global coupled models（BCC-CGCM and BCC-CSM）.The possible causes for the deviations between the model hindcasts and observations are analyzed.The results show that the hindcasts of EASP by BCC-CGCM and BCC-CSM deviate from observations,with the anomaly correlation coefficient（ACC） being-0.01 and-0.09 for the two models,respectively.The SST anomalies in North and West Pacific and the SST index values predicted by the two models also deviate from the observations,indicating that inconsistent SST fields may be the key factor leading to the deviation in the prediction of the EASP decadal shift.Thus,a dynamic-analogue scheme is proposed to correct the precipitation hindcasts by using SSTs,where SST and EASP are highly correlated,to select historical analogue cases.Cross validations show that the average ACC of the temporal-latitude distribution of the EASP between the corrected hindcasts and observations is 0.18 for BCC-CGCM and0.02 for BCC-CSM;both are much higher than the uncorrected hindcasts.Applying the dynamic-analogue correction scheme in both models successfully improves prediction of the EASP decadal change in the late1990 s.

关键词： dynamic-analogue correction scheme East Asian summer precipitation ocean-atmospherecoupled model decadal change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

decadal changes in Climatological Intraseasonal Fluctuation of Subseasonal Evolution of Summer Precipitation over the Korean Peninsula in the mid-1990s

引用

Advances in Atmospheric Sciences 2011年第3期28卷 591-600页

作者： WonMoo KIM Jong-Ghap JHUN Kyung-Ja HA Masahide KIMOTO School of Earth and Environmental Sciences/Research Institute of Oceanography Seoul National University151-742Korea Divison of Earth Environmental System Pusan National University609-735Korea Atmosphere and Ocean Research Institute University of Tokyo277-8564Japan

decadal changes in the subseasonal evolution and the phase-locked climatological intraseasonal fluctuation of summertime rainfall over the Korean Peninsula before and after the mid-1990s are investigated.The activity and the migration speed of the monsoon rain band over the East Asian region are altered in the recent decade,resulting in the drier conditions in late spring and the earlier onset of Changma.In early August when a climatological monsoon break was clear in the earlier decade,the precipitation has increased dramatically with a meridional coherency.The response to the enhanced convection over the South China Sea and southeastern China provides a favorable condition for more precipitation in early August through the changes in moisture transport and tropical cyclone passage.

关键词： decadal change intraseasonal fluctuation East Asian summer monsoon

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

decadal changeS IN WESTERN NORTH PACIFIC TROPICAL CYCLONES ASSOCIATED WITH MADDEN-JULIAN OSCILLATION

引用

Journal of Tropical Meteorology 2016年第2期22卷 109-117页

作者：赵威韦志刚赵海坤郑志远王冀 State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Pacific Typhoon Research Center Key Laboratory of Meteorological Disaster of Ministry of EducationNanjing University of Information Science & Technology Institute of Atmosphere Science North China Regional Climate Center Beijing Meteorological Bureau

This study focuses on the decadal variability of tropical cyclones(TC) over the Western North Pacific(WNP)and how these changes are related to the Madden-Julian Oscillation(MJO).It was done with the help of the Real-time Multivariate MJO index from the Australian Government Bureau of Meteorology of the Centre for Australian Weather and Climate Research,TC data from the Joint Typhoon Warming Center best track datasets,and daily and monthly datasets from the NCEP/NCAR reanalysis center.The results show that the TC frequency in the WNP exhibited a statistically significant decrease during 1998-2010 compared to during 1979-1997.The decrease in TC frequency in the WNP mainly occurred during MJO active phases(i.e.,phases 4,5,6,and 7).Further investigation of the climate background and the propagation differences of the MJO between 1979-1997 and 1998-2010 was performed.The La Nina-like tropical sea surface temperature cooling caused stronger Walker circulation and thus induced unfavorable atmosphere conditions for WNP TC genesis including a low-level easterly anomaly,a negative relative vorticity anomaly,an increase in sea-level pressure,and stronger vertical wind shear.Moreover,shortening of the MJO cycle,decline in the duration of the active phases in the WNP,and easterly anomaly and shrinkage of the convection area during MJO active phases may also partly explain the decadal variation of TC.

关键词： climate EOF tropical cyclone MJO Western North Pacific decadal change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

decadal (2003–2013) changes in liana diversity,abundance and aboveground biomass in four inland tropical dry evergreen forest sites of peninsular India

引用

Journal of Forestry Research 2016年第1期27卷 133-146页

作者： Elumalai Pandian Narayanaswamy Parthasarathy Department of Ecology & Environmental Sciences School of Life Sciences Pondicherry University

In 2013, we re-inventoried all lianas （≥1 cm diameter measured at 1.3 m from the rooting point） in four I-ha permanent plots distributed one each in four sites of inland tropical dry evergreen forest on the Coromandel Coast （Pudukottai district） of peninsular India, established in 2003. Among the four sites, Shanmuganathapuram （SP） and Araiyapatti （AP） were much disturbed and the other two sites （Karisakkadu--KR and Maramadakki--MM） were moderately disturbed. We inventoried a total of 3425 lianas representing 37 species of 33 genera and 22 families. Over a decade （2003-2013） liana species richness increased at two sites （MM and SP） and no changes occurred at the other two sites. Liana abundance increased by 210, 211,164 and 162 individuals at sites AP, KR, MM and SP, respectively, and basal area increased （from 1.09 to 1.76 m2 at AP, 0.67 to 0.86 m2 at KR, 1.68 to 2.06 mz at MM, and from 0.44 to 1.06 m2 at SP）. Over a 10-year period, three species （Abrus precatorius, Canavalia virosa, and Cocculus hirsutus） were lost and five species （Gloriosa superba, Ampelocissus tomentosa, Capparis sepiaria, Aganosma cymosa and Tiliacora acuminata） were newly added. Total aboveground biomass increased by 18.5, 0.74, 3.6 and 9.5 Mg ha-1, respectively, at sites AP, KR, MM and SP.

关键词： Tropical dry evergreen forest Lianaabundance Re-inventory Aboveground biomassHuman disturbance decadal change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

On the Contrasting decadal changes of Diurnal Surface Temperature Range between the Tibetan Plateau and Southeastern China during the 1980s–2000s

引用

Advances in Atmospheric Sciences 2017年第2期34卷 181-198页

作者： Yang YANG Rongcai REN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China 1nstitute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters and KLME Nanjing University of Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China

The diurnal surface temperature range （DTR） has become significantly smaller over the Tibetan Plateau （TP） but larger in southeastern China, despite the daily mean surface temperature having increased steadily in both areas during recent decades. Based on ERA-Interim reanalysis data covering 1979-2012, this study shows that the weakened DTR over TP is caused by stronger warming of daily minimum surface temperature （Tmin） and a weak cooling of the daily maximum surface temper- ature （Tmax）; meanwhile, the enhanced DTR over southeastern China is mainly associated with a relatively stronger/weaker warming of Tmax/Tmin. A further quantitative analysis of DTR changes through a process-based decomposition method-- the Coupled Surface-Atmosphere Climate Feedback Response Analysis Method （CFRAM）--indicates that changes in radia- tive processes are mainly responsible for the decreased DTR over the TR In particular, the increased low-level cloud cover tends to induce the radiative cooling/warming during daytime/nighttime, and the increased water vapor helps to decrease the DTR through the stronger radiative wanning during nighttime than daytime. Contributions from the changes in all radiative processes （over -2℃） are compensated for by those from the stronger decreased surface sensible heat flux during daytime than during nighttime （approximately 2.5℃）, but are co-contributed by the changes in atmospheric dynamics （approximately -0.4℃） and the stronger increased latent heat flux during daytime （approximately -0.8℃）. In contrast, the increased DTR over southeastern China is mainly contributed by the changes in cloud, water vapor and atmospheric dynamics. The changes in surface heat fluxes have resulted in a decrease in DTR over southeastern China.

关键词： Tibetan Plateau diurnal surface temperature range decadal change CFRAM

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Interannual Variation of Tropical Night Frequency in Beijing and Associated Large-Scale Circulation Background

引用

Advances in Atmospheric Sciences 2012年第2期29卷 295-306页

作者： Jong-Kil PARK 陆日宇李超凡 Eun Byul KIM Department of Atmospheric Environment Information Engineering Atmospheric Environment Information Research Center Inje University State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences

This study examined the variability in frequency of tropical night occurrence （i.e., minimum air tem- perature 25℃） in Beijing, using a homogenized daily temperature dataset during the period 1960–2008. Our results show that tropical nights occur most frequently in late July and early August, which is consis- tent with relatively high air humidity associated with the rainy season in Beijing. In addition, year-to-year variation of tropical night occurrence indicates that the tropical nights have appeared much more frequently since 1994, which can be illustrated by the yearly days of tropical nights averaged over two periods： 9.2 days of tropical nights per year during 1994–2008 versus 3.15 days during 1960–1993. These features of tropical night variations suggest a distinction between tropical nights and extreme heat in Beijing. We further investigated the large-scale circulations associated with the year-to-year variation of tropical night occurrence in July and August, when tropical nights appear most frequently and occupy 95% of the annual sum. After comparing the results in the two reanalysis datasets （NCEP/NCAR and ERA-40） and considering the possible effects of decadal change in the frequency of tropical nights that occurred around 1993/94, we conclude that on the interannual time scale, the cyclonic anomaly with a barotropic structure centered over Beijing is responsible for less frequent tropical nights, and the anticyclonic anomaly is responsible for more frequent occurrence of tropical nights over Beijing.

关键词： tropical night large-scale circulation interannual variability decadal change Beijing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Estimating Tree Canopy Cover and Identifying Deforestation Patterns in Meghalaya (1990-2021) through ML Classifiers

引用

Journal of Geographic Information System 2023年第3期15卷 309-333页

作者： Tapan Dhar Sengalvarayan Aravindan Basudeb Bhatta Department of Earth Sciences Annamalai University Annamalai Nagar India CAD Centre Jadavpur University Kolkata India

This study utilizes ML classifiers to estimate canopy density based on three decades of data (1990-2021). The Support Vector Machine (SVM) classifier outperformed other classifiers, such as Random Tree and Maximum Likelihood. Satellite data from Landsat and Sentinel 2 was classified using a developed python model, providing an economical and time-saving approach. The accuracy of the classification was evaluated through a confusion matrix and area computation. The findings indicate a negative trend in the overall decadal change, with significant tree loss attributed to jhum cultivation, mining, and quarry activities. However, positive changes were observed in recent years due to the ban on illegal mining. The study highlights the dynamic nature of tree cover and emphasizes the need for biennial assessments using at least five time-series data. Micro-level analysis in Shallang, West Khasi hills, revealed a concerning trend of shortening jhum cycles. Automation in canopy change analysis is crucial for effective forest monitoring, providing timely information for law enforcement proposals and involving forest managers, stakeholders, and watchdog organizations.

关键词： Meghalaya Forest Cover ML SVM Python Script decadal change Biennial change

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Strengthened Relationship between the Antarctic Oscillation and ENSO After the Mid-1990s during Austral Spring

引用

Advances in Atmospheric Sciences 2017年第1期34卷 54-65页

作者： Tingting HAN Huijun WANG Jianqi SUN Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Climate change Research Center Chinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University for Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China

This paper documents a decadal strengthened co-variability of the Antarctic Oscillation （AAO） and ENSO in austral spring after the mid-1990s. During the period 1979-93, the ENSO （AAO） spatial signatures are restricted to the tropicsmidlatitudes （Antarctic-midlatitudes） of the Southern Hemisphere （SH）, with a weak connection between the two oscillations. Comparatively, after the mid-1990s, the E1 Nifio-related atmospheric anomalies project on a negative AAO pattern with a barotropic structure in the mid-high latitudes of the SH. The expansion of E1 Nifio-related air temperature anomalies have a heightened impact on the meridional thermal structure of the SH, contributing to a weakened circumpolar westerly and strengthened subtropical jet. Meanwhile, the ENSO-related southern three-cell circulations expand poleward and then strongly couple the Antarctic and the tropics. Numerical simulation results suggest that the intensified connection between ENSO and SST in the South Pacific since the mid-1990s is responsible for the strengthened AAO-ENSO relationship.

关键词： ENSO Antarctic Oscillation South Pacific SST austral spring decadal change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：