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Response of the Dominant Modes of Atmospheric Circulation in the Northern Hemisphere to a Projected Arctic Sea Ice Loss in 2007 预览
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作者 FAN Tingting HUANG Fei ZHOU Xiao 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期589-595,共7页
This study revisits the Arctic sea ice extent(SIE) for the extended period of 1979-2015 based on satellite measurements and finds that the Arctic SIE experienced three different periods: a moderate sea ice decline per... This study revisits the Arctic sea ice extent(SIE) for the extended period of 1979-2015 based on satellite measurements and finds that the Arctic SIE experienced three different periods: a moderate sea ice decline period for 1979-1996, an accelerated sea ice decline period from 1997 to 2006, and large interannual variation period after 2007, when Arctic sea ice reached its tipping point reported by Livina and Lenton(2013). To address the response of atmospheric circulation to the lowest sea ice conditions with a large interannual variation, we investigated the dominant modes for large atmospheric circulation responses to the projected 2007 Arctic sea ice loss using an atmospheric general circulation model(ECHAM5). The response was obtained from two 50-yr simulations: one with a repeating seasonal cycle of specified sea ice concentration for the period of 1979-1996 and one with that of sea ice conditions in 2007. The results suggest more occurrences of a negative Arctic Oscillation(AO) response to the 2007 Arctic sea ice conditions, accompanied by an North Atlantic Oscillation(NAO)-type atmospheric circulation response under the largest sea ice loss, and more occurrences of the positive Arctic Dipole(AD) mode under the 2007 sea ice conditions, with an across-Arctic wave train pattern response to the largest sea ice loss in the Arctic. This study offers a new perspective for addressing the response of atmospheric circulation to sea ice changes after the Arctic reached the tipping point in 2007. 展开更多
关键词 ARCTIC sea ice LOSS ARCTIC OSCILLATION ARCTIC DIPOLE atmospheric RESPONSE
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北极航线开发与“冰上丝绸之路”建设:一个文献综述 预览
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作者 李振福 陈卓 +1 位作者 陈雪 陈霄 《中国海洋大学学报:社会科学版》 2019年第2期1-12,共12页
随着'冰上丝绸之路'共建的不断发展,诸多文献从多层次和多角度探究了'冰上丝绸之路'的相关问题以及未来发展趋势,而'冰上丝绸之路'与北极航线开发密切相关,所以将北极航线开发与'冰上丝绸之路'建设相... 随着'冰上丝绸之路'共建的不断发展,诸多文献从多层次和多角度探究了'冰上丝绸之路'的相关问题以及未来发展趋势,而'冰上丝绸之路'与北极航线开发密切相关,所以将北极航线开发与'冰上丝绸之路'建设相关联作为切入点,探索其研究趋势具有重要意义。针对环北极国家及域外国家有关北极航线开发利用的政策和实践、北极航线开发、'冰上丝绸之路'建设以及两者关联性的研究现状进行系统总结和分析。对现有研究进行客观评价,指出目前对北极航线开发与'冰上丝绸之路'建设问题的研究呈现出研究领域范围较广、研究成果集中丰富、研究方法各具特色、研究理论较扎实但一些领域研究仍不够深入、缺乏量化模型支持以及研究理论缺乏系统性等特点。进而提出在研究视角、内容、方法及理论上进一步探讨、发展或突破的空间。 展开更多
关键词 北极 北极航线 北极航线开发 “冰上丝绸之路”
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北极环境保护治理体系的软法局限及其克服——以《北极环境保护战略》和北极理事会为例 预览
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作者 袁雪 张义松 《边界与海洋研究》 2019年第1期67-81,共15页
国际软法理论远远晚于软法治理实践的发展,国内外学者对其定义众说纷纭,至今尚未有统一定论。北极环境治理体系发展过程中已形成了大量软法性质的文件,着眼于北极软法发展演变历程,可以将其划分为监测评估、初步执行和转型三个时期。解... 国际软法理论远远晚于软法治理实践的发展,国内外学者对其定义众说纷纭,至今尚未有统一定论。北极环境治理体系发展过程中已形成了大量软法性质的文件,着眼于北极软法发展演变历程,可以将其划分为监测评估、初步执行和转型三个时期。解读《北极环境保护战略》的内容,可以发现其缺乏独立性、缺乏行动力、缺乏财政资助、成果转化率较低。在承继和发展基础上产生的北极理事会也面临着一些瓶颈。致力于解决北极环境软法治理当下所面临的困境,可以通过制定统一的软法程序法、制定具有科学性和影响力的良性软法、提升成员国违反软法的成本等手段来增强北极软法的效力。 展开更多
关键词 软法 环境治理 北极理事会 北极环境保护战略
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The Rapidly Changing Arctic and Its Impact on Global Climate 预览
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作者 ZHAO Jinping ZHONG Wenli +1 位作者 DIAO Yina CAO Yong 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期537-541,共5页
Arctic sea ice has significant seasonal variability. Prior to the 2000 s, it retreated about 15% in summer and fully recovered in winter. However, by the year 2007, Arctic sea ice extent experienced a catastrophic dec... Arctic sea ice has significant seasonal variability. Prior to the 2000 s, it retreated about 15% in summer and fully recovered in winter. However, by the year 2007, Arctic sea ice extent experienced a catastrophic decline to about 4.28×10^6 km^2, which was 50% lower than conditions in the 1950 s to the 1970 s(Serreze et al., 2008). That was a record low over the course of the modern satellite record, since 1979(note that the year 2012 became the new record low). This astonishing event drew wide-ranging attention in 2007-2009 during the 4 th International Polar Year. The dramatic decline of sea ice attracts many scientists’ interest and has become the focus of intense research since then. Currently, sea ice retreat is not only appearing around the marginal ice zone, but also in the pack ice inside the central Arctic(Zhao et al., 2018). In fact, premonitory signs had already been seen through other evidence. Before the disintegration of the Soviet Union, US naval submarines had been conducting an extensive survey under the sea ice and taking measurements of sea ice thickness. Their measurements revealed a gradual decrease of ice thickness to 1.8 m during winter by the end of the 20 th century, in contrast to the climatological mean of 3.1 m(Rothrock et al., 1999). However, this alarming result did not draw much attention since the Arctic was still severely cold at that time. 展开更多
关键词 ARCTIC Ocean climate change sea ice RETREAT FRESHWATER ACCUMULATION ARCTIC AMPLIFICATION global impacts
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北极斯瓦尔巴德群岛中部海域表层海水水质研究 预览
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作者 李海源 《中国地质调查》 2019年第3期75-80,共6页
掌握北极海水水质特征及地域分布等第一手数据对北极科考意义重大。该项研究工作是全国青少年北极科考子任务,于2017年夏季在北极斯瓦尔巴德群岛中部海域对表层海水水质特征、地域差异及相关控制因素进行了研究。选取了6个区域共40个采... 掌握北极海水水质特征及地域分布等第一手数据对北极科考意义重大。该项研究工作是全国青少年北极科考子任务,于2017年夏季在北极斯瓦尔巴德群岛中部海域对表层海水水质特征、地域差异及相关控制因素进行了研究。选取了6个区域共40个采样点采集表层海水样本,从温度、酸碱度、电导率、溶解性总固体量、实际盐度和溶解氧饱和度等方面进行了水质特征测量分析,发现该海域6个区域在海水温度、电导率、溶解性总固体量、实际盐度及溶解氧饱和度等方面均有较大差异,而酸碱度差异不大:北部冰区水温最低,溶解性总固体量最低,溶解氧含量较高;西北部海湾溶解氧饱和度最高;中部海峡溶解性总固体量最高,盐度和电导率最低;南部海域水温最高,实际盐度和电导率最高,溶解氧饱和度最低;东部沿海水温偏低。采样点地理位置、洋流情况、地形地貌等因素对表层海水水质均有影响。这些研究成果对补充我国在北极地区的第一手科考数据和进行深入的科考研究具有重要意义。 展开更多
关键词 水质 表层海水 北极 斯瓦尔巴德群岛
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Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice 预览
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作者 XING Wen HUANG Fei 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期542-552,共11页
Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal r... Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall(SFR) during early summer(May-June mean, MJ) by considering Arctic sea ice(ASI) variability as a new potential predictor. A MJ SFR index(SFRI), the leading principle component of the empirical orthogonal function(EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations(1979-2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure(SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979-2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models’ ensemble prediction for the 1979-2010 period(0.72 versus 0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall. 展开更多
关键词 East Asia SUBTROPICAL FRONTAL rainfall long-lead seasonal PREDICTION Arctic sea ice Physical-empirical model
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Impacts of SIS and CICE as Sea Ice Components in BCC_CSM on the Simulation of the Arctic Climate 预览
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作者 CHU Min SHI Xueli +3 位作者 FANG Yongjie ZHANG Lujun WU Tongwen ZHOU Bing 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期553-562,共10页
Sea ice is a sensitive indicator of climate change and an important component of climate system models. The Los Alamos Sea Ice Model 5.0(CICE5.0) was introduced to the Beijing Climate Center Climate System Model(BCC_C... Sea ice is a sensitive indicator of climate change and an important component of climate system models. The Los Alamos Sea Ice Model 5.0(CICE5.0) was introduced to the Beijing Climate Center Climate System Model(BCC_CSM) as a new alternative to the Sea Ice Simulator(SIS). The principal purpose of this paper is to analyze the impacts of these two sea ice components on simulations of basic Arctic sea ice, atmosphere, and ocean states. Two sets of experiments were conducted with the same configurations except for the sea ice component used, i.e., SIS and CICE. The distributions of sea ice concentration and thickness reproduced by the CICE simulations in both March and September were closer to actual observations than those reproduced by SIS simulations, which presented a very thin sea ice cover in September. Changes in sea ice conditions also brought about corresponding modifications to the atmosphere and ocean circulation. CICE simulations showed higher agreement with the reference datasets than did SIS simulations for surface air temperature, sea level pressure, and sea surface temperature in most parts of the Arctic Ocean. More importantly, compared with simulations with SIS, BCC_CSM with CICE revealed stronger Atlantic meridional overturning circulation(AMOC), which is more consistent with actual observations. Thus, CICE shows better performance than SIS in BCC_ CSM. However, both components demonstrate a number of common weaknesses, such as overestimation of the sea ice cover in winter, especially in the Nordic Sea and the Sea of Okhotsk. Additional studies and improvements are necessary to develop these components further. 展开更多
关键词 BCC_CSM CICE SIS sea ice ARCTIC climate
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Comparison of Phytoplankton Communities Between Melt Ponds and Open Water in the Central Arctic Ocean 预览
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作者 ZHANG Tianzhen ZHUANG Yanpei +4 位作者 JIN Haiyan LI Ke JI Zhongqiang LI Yangjie BAI Youcheng 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期573-579,共7页
Climate warming has a significant impact on the sea ice and ecosystem of the Arctic Ocean.Under the increasing numbers of melt ponds in Arctic sea ice,the phytoplankton communities associated with the ice system are c... Climate warming has a significant impact on the sea ice and ecosystem of the Arctic Ocean.Under the increasing numbers of melt ponds in Arctic sea ice,the phytoplankton communities associated with the ice system are changing.During the 7th Chinese National Arctic Research Expedition cruise in summer 2016,photosynthesis pigments and nutrients were analyzed,revealing differences in phytoplankton communities between melt ponds and open water in the central Arctic.Photosynthetic pigment analysis suggested that Fuco(5-91μg m^-3)and Diadino(4-21μg m^-3)were the main pigments in the open water.However,the melt ponds had high concentrations of Viola(7-30μg m^-3),Lut(4-59μg m^-3)and Chl b(11-38μg m^-3),suggesting that green algae dominated phytoplankton communities in the melt ponds.The significant differences in phytoplankton communities between melt ponds and open water might be due to the salinity difference.Moreover,green algae may play a more important role in Arctic sea ice ecosystems with the expected growing number of melt ponds in the central Arctic Ocean. 展开更多
关键词 the CENTRAL Arctic Ocean MELT PONDS PHOTOSYNTHESIS pigments nutrients PHYTOPLANKTON COMMUNITIES
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A Correction Algorithm for Atmospheric Visibility Based on Fog Droplet Size Data Obtained on a Moving Ship During 2016 Arctic Cruise 预览
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作者 LIU Yilin ZHAO Jinping 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期596-604,共9页
In this study, we measured the droplet size distribution(DSD) and visibility of sea fog using a fog droplet spectrometer and visibility meter, respectively, during the July 23-August 3 and August 22-September 13 perio... In this study, we measured the droplet size distribution(DSD) and visibility of sea fog using a fog droplet spectrometer and visibility meter, respectively, during the July 23-August 3 and August 22-September 13 periods of the 2016 Chinese National Arctic Research Expedition. We calculated the visibility using the Mie theory and the DSD data and then compared the calculated with the observed visibility. The comparison shows that the deviations in the calculated visibility caused by DSD data sampling errors cannot be ignored. During navigation, wind and ship speeds tended to push or pull the sampled air and cause turbulence pulsation, which influenced the sampling of the fog droplet spectrometer. This influence is weak when the liquid water content(LWC) is high but becomes stronger as the LWC decreases. Taking the sailing speed and heading into consideration, the wind speed component parallel and perpendicular to the air inlet of the fog droplet spectrometer exhibit different laws in the deviation. By performing a fitting analysis of the calculated and observed visibilities under different wind speeds and wind directions, here, we present two sets of correction coefficients for the two wind-speed components and a method for correcting the calculated visibility. This correction method shows excellent results. 展开更多
关键词 ARCTIC sea FOG FOG DROPLET size distribution liquid water content VISIBILITY MIE theory
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Estimation of Oceanic Heat Flux Under Sea Ice in the Arctic Ocean 预览
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作者 LIN Long ZHAO Jinping 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期605-614,共10页
Oceanic heat flux(Fw) is the vertical heat flux that is transmitted to the base of sea ice. It is the main source of sea ice bottom melting. The residual method was adopted to study oceanic heat flux under sea ice. Th... Oceanic heat flux(Fw) is the vertical heat flux that is transmitted to the base of sea ice. It is the main source of sea ice bottom melting. The residual method was adopted to study oceanic heat flux under sea ice. The data acquired by 28 ice mass balance buoys(IMBs) deployed over the period of 2004 to 2013 in the Arctic Ocean were used. Fw values presented striking seasonal and spatial variations. The average summer Fw values for the Canada Basin, Transpolar Drift, and Multiyear Ice area were 16.8, 7.7, and 5.9 W m^-2, respectively. The mean summer F-w for the whole Arctic was 10.1 W m^-2, which was equivalent to a bottom melt of 0.4 m. Fw showed an autumn peak in November in the presence of the near-surface temperature maximum(NSTM). The average Fw for October to December was 3.7 W m^-2. And the average Fw for January to March was 1.0 W m^-2, which was approximately one third of the average Fw in the presence of NSTM. The summer Fw was almost wholly attributed to the incident solar radiation that enters the upper ocean through leads and the open water. Fw calculated through the residual method using IMB data was compared with that calculated through the parameterization method using Autonomous Ocean Flux Buoy data. The results revealed that the Fw provided by the two methods were consistent when the sea ice concentration exceeded 70% and mixing layer temperature departure from freezing point was less than 0.15℃. Otherwise, the Fw yielded by the residual method was approximately one third smaller than that provided by the parameterization method. 展开更多
关键词 ARCTIC OCEAN OCEANIC HEAT flux RESIDUAL method NSTM HEAT release
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Transition Periods Between Sea Ice Concentration and Sea Surface Air Temperature in the Arctic Revealed by an Abnormal Running Correlation 预览
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作者 JI Xupeng ZHAO Jinping 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第3期633-642,共10页
This study used the synthetic running correlation coefficient calculation method to calculate the running correlation coefficients between the daily sea ice concentration(SIC) and sea surface air temperature(SSAT) in ... This study used the synthetic running correlation coefficient calculation method to calculate the running correlation coefficients between the daily sea ice concentration(SIC) and sea surface air temperature(SSAT) in the Beaufort-Chukchi-East Siberian-Laptev Sea(BCEL Sea), Kara Sea and southern Chukchi Sea, with an aim to understand and measure the seasonally occurring changes in the Arctic climate system. The similarities and differences among these three regions were also discussed. There are periods in spring and autumn when the changes in SIC and SSAT are not synchronized, which is a result of the seasonally occurring variation in the climate system. These periods are referred to as transition periods. Spring transition periods can be found in all three regions, and the start and end dates of these periods have advancing trends. The multiyear average duration of the spring transition periods in the BCEL Sea, Kara Sea and southern Chukchi Sea is 74 days, 57 days and 34 days, respectively. In autumn, transition periods exist in only the southern Chukchi Sea, with a multiyear average duration of only 16 days. Moreover, in the Kara Sea, positive correlation events can be found in some years, which are caused by weather time scale processes. 展开更多
关键词 ARCTIC SEA ice CONCENTRATION SEA surface air temperature synthetic running CORRELATION coefficient transition period
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Behavior of the Total Electron Content over the Arctic and Antarctic sectors during several intense geomagnetic storms
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作者 Gustavo A.Mansilla 《大地测量与地球动力学:英文版》 2019年第1期26-36,共11页
In this paper,the behavior of TEC at three stations located in the Arctic and Antarctic sectors during some intense geomagnetic storms in the period 2012-2016 is analyzed.The results show the opposite storm effects in... In this paper,the behavior of TEC at three stations located in the Arctic and Antarctic sectors during some intense geomagnetic storms in the period 2012-2016 is analyzed.The results show the opposite storm effects in the Arctic and Antarctic regions.Both the positive and negative TEC disturbances presented more fluctuations over the Arctic stations than over the Antarctic stations.Moreover,the positive TEC disturbances were more significant in winter.The negative disturbances were generally long-lasting,sometimes interrupted by short-duration positive disturbances.Overall,the increases and decreases in TEC can be mainly attributed to changes(i.e.,increase and decreases in the O/N2 ratio respectively)in the thermospheric composition,but prompt penetration electric field could be responsible for the initial TEC disturbances.The thermospheric circulation and the disturbance dynamo,which are maintained due to prolonged high-energy input at high latitudes,can also play important roles at the end of main phase and during recovery phase. 展开更多
关键词 GEOMAGNETIC storms TEC ARCTIC and ANTARCTIC SECTORS
极地水声信号处理研究
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作者 尹力 王宁 +1 位作者 殷敬伟 李启虎 《中国科学院院刊》 CSSCI CSCD 北大核心 2019年第3期306-313,共8页
北极地区因其特殊的战略地位和地球持续变暖的趋势而备受关注。北极及其毗邻海域的水声学研究在北极海洋科学研究中占有重要的地位。极地水声信号处理较其他水声信号处理领域研究起步较晚,主要针对极区海域特别是北极海洋环境开展水声... 北极地区因其特殊的战略地位和地球持续变暖的趋势而备受关注。北极及其毗邻海域的水声学研究在北极海洋科学研究中占有重要的地位。极地水声信号处理较其他水声信号处理领域研究起步较晚,主要针对极区海域特别是北极海洋环境开展水声环境效应及其适配处理研究。文章介绍二战结束后开始的北极及其毗邻海域的水声学研究概况,并说明这一特殊海域的海洋水声研究的特点和有别于传统水声研究的内容。介绍北极水声环境研究的重要性,以及对水声信号处理、声呐装备的特殊要求,和我们应该采取的应对措施。 展开更多
关键词 北极 水声信号处理 声呐 观测 通信 导航 定位
Towards reliable Arctic sea ice prediction using multivariate data assimilation
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作者 Jiping Liu Zhiqiang Chen +11 位作者 Yongyun Hu Yuanyuan Zhang Yifan Ding Xiao Cheng Qinghua Yang Lars Nerger Gunnar Spreen Radley Horton Jun Inoue Chaoyuan Yang Ming Li Mirong Song 《科学通报:英文版》 SCIE EI CSCD 2019年第1期63-72,共10页
Rapid declines in Arctic sea ice have captured attention and pose significant challenges to a variety of stakeholders.There is a rising demand for Arctic sea ice prediction at daily to seasonal time scales,which is pa... Rapid declines in Arctic sea ice have captured attention and pose significant challenges to a variety of stakeholders.There is a rising demand for Arctic sea ice prediction at daily to seasonal time scales,which is partly a sea ice initial condition problem,Thus,a multivariate data assimilation that integrates sea ice observations to generate realistic and skillful model initialization is needed to improve predictive skill of Arctic sea ice.Sea ice data assimilation is a relatively new research area,In this review paper,we focus on two challenges for implementing multivariate data assimilation systems for sea ice forecast,First,to address the challenge of limited spatiotemporal coverage and large uncertainties of observations,we discuss sea ice parameters derived from satellite remote sensing that (1)have been utilized for improved model initialization,including concentration,thickness and drift,and (2)are currently under develop- ment with the potential for enhancing the predictability of Arctic sea ice,including melt ponds and sea ice leads.Second,to strive to generate the "best"estimate of sea ice initial conditions by combining model simulations]forecasts and observations,we review capabilities and limitations of different data assimilation techniques that have been developed and used to assimilate observed sea ice parameters in dynamical models. 展开更多
关键词 ARCTIC sea ice PREDICTION Remote sensing Data ASSIMILATION
Satellite-observed trends in the Arctic sea ice concentration for the period 1979–2016 预览
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作者 WANG Yunhe BI Haibo +5 位作者 HUANG Haijun LIU Yanxia LIU Yilin LIANG Xi FU Min ZHANG Zehua 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期18-37,共20页
Arctic sea ice cover has decreased dramatically over the last three decades.This study quantifi es the sea ice concentration(SIC)trends in the Arctic Ocean over the period of 1979–2016 and analyzes their spatial and ... Arctic sea ice cover has decreased dramatically over the last three decades.This study quantifi es the sea ice concentration(SIC)trends in the Arctic Ocean over the period of 1979–2016 and analyzes their spatial and temporal variations.During each month the SIC trends are negative over the Arctic Ocean,wherein the largest(smallest)rate of decline found in September(March)is-0.48%/a(-0.10%/a).The summer(-0.42%/a)and autumn(-0.31%/a)seasons show faster decrease rates than those of winter(-0.12%/a)and spring(-0.20%/a)seasons.Regional variability is large in the annual SIC trend.The largest SIC trends are observed for the Kara(-0.60%/a)and Barents Seas(-0.54%/a),followed by the Chukchi Sea(-0.48%/a),East Siberian Sea(-0.43%/a),Laptev Sea(-0.38%/a),and Beaufort Sea(-0.36%/a).The annual SIC trend for the whole Arctic Ocean is-0.26%/a over the same period.Furthermore,the infl uences and feedbacks between the SIC and three climate indexes and three climatic parameters,including the Arctic Oscillation(AO),North Atlantic Oscillation(NAO),Dipole anomaly(DA),sea surface temperature(SST),surface air temperature(SAT),and surface wind(SW),are investigated.Statistically,sea ice provides memory for the Arctic climate system so that changes in SIC driven by the climate indices(AO,NAO and DA)can be felt during the ensuing seasons.Positive SST trends can cause greater SIC reductions,which is observed in the Greenland and Barents Seas during the autumn and winter.In contrast,the removal of sea ice(i.e.,loss of the insulating layer)likely contributes to a colder sea surface(i.e.,decreased SST),as is observed in northern Barents Sea.Decreasing SIC trends can lead to an in-phase enhancement of SAT,while SAT variations seem to have a lagged infl uence on SIC trends.SW plays an important role in the modulating SIC trends in two ways:by transporting moist and warm air that melts sea ice in peripheral seas(typically evident inthe Barents Sea)and by exporting sea ice out of the Arctic Ocean via passages into the Greenland and Barents Seas, 展开更多
关键词 SEA ice concentration(SIC) Arctic Ocean SURFACE air temperature(SAT) SEA SURFACE temperature(SST) SURFACE wind(SW) INTERANNUAL and DECADAL oscillation
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United Nations Environment Programme's 2018 Observer Activities Report to the Arctic Council 预览
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《中华海洋法学评论(中英文版)》 2019年第1期152-157,共6页
I. The Organization’s contributions to the work of the Arctic Council’s Working Groups, Task Forces, and/or Expert Groups The United Nations Environment Programme (UN Environment) has been active as an Observer to t... I. The Organization’s contributions to the work of the Arctic Council’s Working Groups, Task Forces, and/or Expert Groups The United Nations Environment Programme (UN Environment) has been active as an Observer to the Arctic Council since 1996, taking part in the Council’s Ministerial, Senior Arctic Officials meetings and, together with its collaborating centre GRID-Arendal in Norway and the UN Environment World Conservation Monitoring Centre (UNEP-WCMC) in the UK, has engaged actively in the efforts of most of the Council’s scientific and technical working groups. As the United Nation’s organization setting the global environmental agenda and along with the Multilateral Environmental Agreement (MEA) it administers—including those on biological diversity, hazardous waste, chemicals and mercury—UN Environment has facilitated global outreach for some of the Council’s work. Notably, UN Environment continues to provide technical support on a number of assessment and monitoring activities as described below. 展开更多
关键词 United Nations Environment Programme's OBSERVER ACTIVITIES REPORT the ARCTIC COUNCIL
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Influence of gaseous and particulate species on neutralization processes of polar aerosol and snow — A case study from Ny-Alesund
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作者 Roseline C.Thakur Meloth Thamban 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期12-25,共14页
The inter-conversion of nitrogen and sulfur species between the gas and particulate phases and their interaction with alkaline species influences the acidity of the aerosols and surface snow. To better understand thes... The inter-conversion of nitrogen and sulfur species between the gas and particulate phases and their interaction with alkaline species influences the acidity of the aerosols and surface snow. To better understand these processes, a short field campaign was undertaken in Ny-Alesund, Svalbard, during 13th April 2012 to 24th April 2012. Air measurements were carried out through a particulate sampler equipped with denuders and filter packs for simultaneous collection of trace gases (HNO3, NO2, SO2 and reactive nitrogen compounds) and aerosols, with daily collection of snow samples. Ionic composition of the samples was analyzed using ion chromatography technique. The results suggested that nitrate-rich aerosols are formed when PAN (peroxy acetyl nitrate) disassociates to form NO2 and HNO3 which further hydrolyzes to form pNO3^- (particulate nitrate). This resulted in a high contribution of pNO3^- (62%) to the total nitrogen budget over the study area. The acidity of the aerosols and snow evaluated through cation/anion ratio (C/A) indicated alkaline conditions with C/A > 2. The bicarbonates/carbonates of Mg^2+ played an important role in neutralization processes of surface snow while the role of NH3 was dominant in aerosol neutralization processes. Such neutralization processes can increase the aerosol hygroscopicity causing warming. Chloride depletion in the snow was significant as compared to the aerosols, indicating two important processes, scavenging of coarse sea salt by the snow and gaseous adsorption of SO2 on the snow surface. However, a more systematic and long term study is required for a better understanding of the neutralization processes and chemical inter-conversions. 展开更多
关键词 PARTICULATE AEROSOL SCAVENGING NEUTRALIZATION ARCTIC
Progresses and advances in Arctic underwater acoustics study
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作者 LI Qihu HUANG Haining +4 位作者 YIN Li WEI Chonghua LI Yu XUE Shanhua LUAN Jingde 《声学学报:英文版》 CSCD 2019年第1期1-20,共20页
As a part of underwater acoustics,the study and development of Arctic Acoustics is later than underwater acoustics about several hundred years.After World War Ⅱ,the study of Arctic Acoustics attracts many interests b... As a part of underwater acoustics,the study and development of Arctic Acoustics is later than underwater acoustics about several hundred years.After World War Ⅱ,the study of Arctic Acoustics attracts many interests by some developed countries,especially U.S.and pre-Soviet Union.The research works obviously have some kinds of cold war brand.After the Cold War,with the gradual warming trend of Arctic area,the ocean & acoustic environment in Arctic and its adjacent area have been considerably concerned.The 8 countries of Arctic rim organized exclusive "Arctic Council"in 1996.The white paper of "China Arctic Policy" was published in January 26,2018,the Chinese government declared that China is a close Arctic country,and is the responsible stakeholder of Arctic interests.The new advances in Arctic research works are introduced in this paper,including the results of scientific survey and studies about Arctic underwater acoustics of Chinese researchers.It is showed that the Arctic underwater acoustical research area is not only parallely copy the topics what traditional underwater acoustics covered,e.g.environment noise,reverberation,and propagation,but also the topics which is specifically based on the Arctic environment.Some of these research fields cannot be included in the traditional shallow water,deep water acoustics,e.g.the ice-water interface feature,ice covered semi-acoustic channel effect,the communication and navigation of UUV in the condition of under ice,and the adaptation of sonar technique,equipment in the ice-covered environment,etc. 展开更多
关键词 Progresses ADVANCES ARCTIC UNDERWATER ACOUSTICS STUDY
Multipath structure of the typical under-ice sound channel in the Arctic:theory and experiment
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作者 LIU Chonglei HUANG Haining +3 位作者 YIN Li LIU Na WEI Chonghua LI Qihu 《声学学报:英文版》 CSCD 2019年第1期21-34,共14页
Considering the typical acoustic environment of the Arctic,this paper proposes a method based on OASES-Bellhop coupled model to rapidly analyze the multipath structure of the under-ice sound channel.Firstly the propos... Considering the typical acoustic environment of the Arctic,this paper proposes a method based on OASES-Bellhop coupled model to rapidly analyze the multipath structure of the under-ice sound channel.Firstly the proposed model refers to ice plate as stratified elastic media with some roughness.Secondly,it uses the perturbation method and Kirchhoff approximation theory to solve the scattering loss due to the sea ice inhomogeneity.Finally,the model predicts the multipath structure of the under-ice channel through Ray theory.The results of the numerical simulation and experiment indicate that the typical Arctic sound channel presents multipath structures due to the sea ice and seabed in the range of 6km,respectively. The sea ice reflection paths are stable,with a short multipath spread within 14 ms.The seabed reflection paths have relatively weak strength.The proposed OASES-Bellhop coupled model successfully predicts the amplitude and delay of the multipath structure with small error, which indicates the proposed model is able to analyze and predict the multipath structure of the observed acoustic environment in experiment. 展开更多
关键词 ARCTIC MULTIPATH structure TYPICAL under-ice SOUND CHANNEL
Myths and Legends-Northern Europe
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作者 Freddie Gay 《英语世界》 2019年第1期127-128,共2页
Finland The lights were created by the Arctic fox.This kindof fox only lives in the Arctio—a—large,cold region inthe far north of our planet.When one of these foxesplayed in the snow,it threw it into the air wim its... Finland The lights were created by the Arctic fox.This kindof fox only lives in the Arctio—a—large,cold region inthe far north of our planet.When one of these foxesplayed in the snow,it threw it into the air wim its tail.The snow was then caught by the light of the moon which created the Northern Lights. 展开更多
关键词 EUROPE MYTHS ARCTIC FOX
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