利用drifter资料分析南海北部涡旋特征

利用卫星跟踪的drifter表面漂流浮标轨迹资料,对南海北部的涡旋特征进行了时空分布统计分析,特别是卫星高度计资料无法分辨出的次级中尺度涡旋的特征,并初步分析了其动力机理。研究发现南海北部半径小于10km的次级涡旋要占所有涡旋的绝大部分,涡旋平均半径可达11.7km,反气旋涡数量与气旋涡数量之比约为2.6∶1。研究结果可为未来在南海布放drifter浮标提供技术参考。

Surface current field and seasonal variability in the Kuroshio and adjacent regions derived from satellite-tracked drifter data

The muhiyear averaged surface current field and seasonal variability in the Kuroshio and adjacent regions are studied. The data used are trajectories and （1/4） ° latitude by （1/4） ° longitude mean currents derived from 323 Argos drifters deployed by Chinese institutions and world ocean circulation experiment from 1979 to 2003. The results show that the Kuroshio surface path adapts well to the western boundary topography and exhibits six great turnings. The branching occurs frequently near anticyclonic turnings rather than near cyclonic ones. In the Luzon Strait, the surface water intrusion into the South China Sea occurs only in fall and winter. The Kuroshio surface path east of Taiwan, China appears nearly as straight lines in summer, fall, and winter, when anticyclonic eddies coexist on its right side; while the path may cyclonically turning in spring when no eddy exists. The Kuroshio intrusion northeast of Taiwan often occurs in fall and winter, but not in summer. The running direction, width and velocity of the middle segment of the Kuroshio surface currents in the East China Sea vary seasonally. The northward intrusion of the Kuroshio surface water southwest of Kyushu occurs in spring and fall, but not in summer. The northmost position of the Kuroshio surface path southwest of Kyushu occurs in fall, but never goes beyond 31 °N. The northward surface current east of the Ryukyu Islands exists only along Okinawa-Amami Islands from spring to fall. In particular, it appears as an arm of an anti- cyclonic eddy in fall.

Surface circulation patterns observed by drifters in the Yellow Sea in summer of 2001,2002 and 2003

In summer of 2001, 2002 and 2003, ten, six and seventeen satellite-tracked surface drifters with drogues centered at 15 and 4 m were deployed, respectively, in the southern Yellow Sea (YS). 23 drifters of them transmitted useful data of at least 30 days. The wind-driven component of the drift was removed from the original drift velocity of drifters. The wind data used are from NCEP (National Center for Environmental Prediction), USA.Trajectories and drift velocities of the 23 drifters depicted the upper circulation structure in the southern YS.There exists an anti-cyclonic eddy with a mean speed and radius of 0.063 m/s and 50km in the central southern YS, whose center lingered within 35.3-36.0°N / 123.5-124.0°E. Showed by 6 drifters, a basin-scale elliptic cyclonic gyre with a mean speed of 0.114 m/s, long and short radius of 250 and 200 km surrounds the anti-cyclonic eddy. In the southwestern part of the southern YS has obvious frontal eddy activities within about100 km with a mean speed about 0.076 m/s. All the drifters passing Korean coast were staggering for more than10 days west of a protruding cape of central Korea. A small-scale cyclonic eddy centered at around 120.5°E/35.1°N with a mean speed of 0.048 m/s was observed in western part of the southern YS.

Characterizing the capability of mesoscale eddies to carry drifters in the northwest Pacific

Mesoscale eddies are common oceanic phenomena.Although many related studies have been conducted,the ability for mesoscale eddies to carry real particles remains poorly addressed.We considered the drifters as real particles to characterize the capability of mesoscale eddies to carry particles.Firstly,mesoscale eddies in the northwest Pacific(99°E-180°E,0°-66°N)were identified using sea level anomaly(SLA)data from 1993 to 2015.Secondly,three important parameters(the carrying days,the number of circles the drifter revolving around the eddy center,and the carrying distances)were calculated by colocalizing eddy data with drifters.Finally,statistical analysis and composite analysis were conducted,reflecting the capability of mesoscale eddies to carry particles.The mechanisms on the carrying capability of eddies were also discussed.Results show that(1)the motion of carried drifters reflects the upper limit of rotational speed of eddies that the drifters revolve around the eddy center by≤90°for one day in most cases;(2)the drifters tend to be carried for a longer time when their minimal distances to the eddy center measured with normalized distance are small;(3)there are two types of eddies(cyclonic and anticyclonic eddies)in different subregions of northwest Pacific,and each has a different carrying capability(on average,similar in the tropical ocean and Subtropical Countercurrent,cyclonic eddies tend to have stronger carrying capability in Southern Kuroshio Extension,and anticyclonic eddies tend to have stronger carrying capability in Northern Kuroshio Extension and Subarctic Gyre);(4)on average,the carried drifters tend to travel for a longer time around the normalized eddy radii ranging from 0.41 to 0.76;(5)the carrying days are related to the Rossby number of the eddy(in general when the Rossby number is smaller,the carrying days are longer).

A Dataset of Global Ocean Surface Currents for 1999-2007 Derived from Argo Float Trajectories: A Comparison with Surface Drifter and TAO Measurements

A dataset of surface current vectors with error estimate from 1999 to 2007 is derived from the trajectories of the Array for Real-time Geostrophic Oceanography (Argo) drifting on surface over the global ocean. The error of the estimated surface currents is about 4.7 cm s-1 which is equivalent to the accuracy of the currents determined from the surface drifters. Geographically, the Argo-derived surface currents can fill many gaps left by the Global Drifter Program due to the greater number of floats, and can provide a complementary in situ observational system for monitoring global ocean surface currents. The surface currents from the Argo floats are compared with the surface drifter-derived currents and the Tropical Atmosphere Ocean program (TAO) measurements. The comparisons show good agreement for both the current amplitude and the direction of surface currents. Results indicate the feasibility of obtaining ocean surface currents from the Argo array and of combining the surface currents from Argo and the ocean surface drifters for in situ mapping of the global surface currents. The authors also make the dataset available to users of interest for many types of applications.

Mechanistic Drifting Forecast Model for A Small Semi-Submersible Drifter Under Tide–Wind–Wave Conditions

Understanding the drifting motion of a small semi-submersible drifter is of vital importance regarding monitoring surface currents and the floating pollutants in coastal regions. This work addresses this issue by establishing a mechanistic drifting forecast model based on kinetic analysis. Taking tide–wind–wave into consideration, the forecast model is validated against in situ drifting experiment in the Radial Sand Ridges. Model results show good performance with respect to the measured drifting features, characterized by migrating back and forth twice a day with daily downwind displacements. Trajectory models are used to evaluate the influence of the individual hydrodynamic forcing. The tidal current is the fundamental dynamic condition in the Radial Sand Ridges and has the greatest impact on the drifting distance. However, it loses its leading position in the field of the daily displacement of the used drifter. The simulations reveal that different hydrodynamic forces dominate the daily displacement of the used drifter at different wind scales. The wave-induced mass transport has the greatest influence on the daily displacement at Beaufort wind scale 5–6; while wind drag contributes mostly at wind scale 2–4.

Drifter轨迹与FVCOM模型轨迹对比数据处理方法的研究

Drifter监测洋流轨迹与FVCOM模型模拟轨迹对比可以发现模型不足,进而优化模型,对比的精度制约着模型优化的程度。针对Nearest洋流轨迹对比数据处理方法精度不高的问题,提出将Wachspress Interpolation、BP神经网络和加权平均3种数据处理方法用于drifter漂流轨迹与FVCOM模型轨迹对比,用分离速度与距离比作为精度指标。结果显示Wachspress Interpolation数据处理方法在分离速度与距离比方面都优于其他3种方法;BP神经网络受训练样本区域大小、样本数据影响以及模型点匹配限制,对比精度最差;Nearest与加权平均法对比效果介于两者之间。实验结果表明新提出的Wachspress Interpolation方法对比精度更高,更加适用于Drifter轨迹与FVCOM模型轨迹对比,该研究结论可应用于后续的模型优化。

Wintertime Guangdong coastal currents successfully captured by cheap GPS drifters

This study introduces a type of self-developed, GPS-based, simple and cheap Surface Current Experiment(SUCE)drifters designated for observing surface coastal currents. By examining trajectories of six drifters deployed in the Daya Bay and the drifter-derived velocities, we conclude that such drifters are generally capable of capturing the characteristics of wintertime surface coastal currents along the Guangdong coast.

Mobile Infrastructure for Monitoring, Modeling, and Forecasting of Coastal Weather Events. Phase I: Building the Smart Drifter

Our goal is to address a critical need to improve monitoring and forecasting of storm-induced coastal flooding (i.e., storm surge). The fundamental element of our approach is a new class of smart drifter—low-cost, rapidly deployable sensors used to collect surge information in advance of, during, and following significant weather events. These devices, each a bit larger than a tennis ball, will be deployed in advance of oncoming storms. The devices will log surge information used for post processing. In this paper, we present the Phase I of the project: the design and development of the smart drifter.

“老漂族”返乡自我养老选择的影响机制研究

城市化进程的加快导致大量老年人进城照顾孙辈、料理家务,“老漂族”群体由此产生。随着老龄化现象的加剧,“老漂族”养老日渐成为一个新的社会问题。根据个人生命周期和养老空间选择的双重维度,“老漂族”的养老方式可分为四种类型:返乡自我养老、返乡家庭养老、进城抚育式养老和进城家庭养老。大部分“老漂族”更愿意选择返乡自我养老,而他们选择这种养老方式的影响机制包括三个方面:第一,利他主义心理,“老漂族”认为自己是家庭负担,返乡自我养老能减轻子女家庭的压力;第二,“老漂族”在城市中往往属于边缘者、弱者角色,难以形成身份认同以及获得归属感,而返乡自我养老能获得身份认同和归属感;第三,个体化的需求,“老漂族”返乡自我养老能获得独立的空间和自由的闲暇时间,并减少与子女之间的矛盾。

《少年漂泊者》与革命文学的蒋光慈模式

蒋光慈是中国共产党早期党员之一,也是中国现代革命文学的奠基人。虽然《少年漂泊者》是蒋光慈的小说开篇、革命文学的初期样本,但是却具有特殊的历史价值与双重的历史意义。在政治意义上,它是当时关心国家民族命运、热心追求革命的进步青年的“指路明灯”,是革命家认识社会、理解时代的一面镜子。在文学意义上,它不仅开创与引领了革命文学的创作潮流,而且以鲜明的阶级立场与叙事伦理、明确的内容取舍与价值倾向,以及具有示范意义的叙事形式,确立了革命文学的写作范式——蒋光慈模式。《少年漂泊者》是弘扬红色文化、传承红色基因的革命文学范本。

THE EFFECT OF KUROSHIO ON THE CIRCULATION IN CHINA SEAS-FROM SATELLITE-TRACKED DRIFTER DATA

A dataset derived from satellite-tracked drifting buoy archived at the Marine Envimoment Data Service (MEDS) in Canada are analyzed to study the effect of the Kuroshio on the China Seas, and the results can exhibit the spacial difference and temporal difference of the effect of Kuroshio on the circulation in the China Seas.

Surface currents measured by GPS drifters in Daya Bay and along the eastern Guangdong coast

GPS-based surface drifters were used to investigate the surface currents in Daya Bay and along the eastern Guangdong coast in China.Surface current vectors were measured based on the GPS location and corresponding time information sent by drifters through the mobile phone network.The analysis of data from 120 drifters,deployed in late spring 2018 in the case-study region,shows that the drifters are generally capable of capturing the surface(tidal and residual)currents.The drifter trajectories suggest an anticlockwise surface current inside Daya Bay and a north-eastward current along the eastern Guangdong coast,where the coastal current along the eastern Guangdong coast is faster than that inside Daya Bay.The surface currents in the investigated region follow an irregular semidiurnal cycle due to the influence of the tidal current,while the currents inside Daya Bay are strongly affected by the topography.According to the harmonic analysis,an irregular semidiurnal type of tidal current is evident at a study grid inside Daya Bay,with an Eulerian residual current speed of 9.0 cm/s and a direction of 276°.The Lagrangian residual current outside Daya Bay moves north-eastward with a mean speed of 22 cm/s along the eastern Guangdong coast,while the current inside Daya Bay moves northward to the bay head with a mean speed of about 8.0 cm/s,which agrees well with the one reported in other literatures.

基于Argos漂流浮标资料的南海及邻近海域次中尺度涡识别及特征分析

次中尺度涡作为连接中尺度涡和微小湍流之间的纽带,对海洋中能量串级和物质输运具有重要的影响。为研究南海及邻近海域次中尺度涡的分布特征和变化规律,本文开发了一种基于拉格朗日漂流轨迹几何特征的次中尺度涡识别方法,并对全球浮标计划中2000年至2022年进入研究海域的1 685个Argos漂流浮标轨迹数据进行了分析,共识别得到11 988个次中尺度涡。研究海域次中尺度涡的半径和生命周期呈正相关,多在3 km和24 h以内,反气旋涡与气旋涡数量之比约为5∶1。次中尺度涡高频出现于南海北部,由吕宋海峡西北部沿陆坡向西南方向递减。在中南半岛南部,次中尺度气旋涡相对更为活跃。研究海域次中尺度涡季节变化信号明显,冬、夏季相对活跃,春、秋季较少。

老漂族城市融入的多重困境与制度优化

城市老漂族这一特殊群体涉及“三孩”政策、积极应对人口老龄化国家战略的有效实施。目前,老漂族是子女与家庭关系难处理的失落者、农村与城市文化难认同的异乡人、时间与空间难兼顾的两面人,国家可以通过完善养老基本法律制度、社会公共服务体系、社会保障政策、帮扶政策等来解决老漂族的城市融入问题。

“后海角时代”台湾地区电影中漂泊者形象研究

台湾地区错综复杂的历史传统和现实情貌,让后海角时代台湾地区电影中漂泊者得以生成。他们身上烙有明显的“历史性”与“现实性”的伤痕印记,这些伤痕印记在漂泊影像中照见和体认了其主体性的危机。面对危机,重建主体性成为漂泊个体乃至集体的强烈诉求,但其在建构过程中,漂泊者的主体性从未澄明,结果也以失败告终,而失败的背后所折射的正是台湾地区社会的悲情和文化失根的现实。

初创陶瓷文化创意品牌路径研究——以“景漂”创建陶瓷工作室为例

本文以“景漂”创建陶瓷工作室为例,探讨了初创陶瓷文化创意品牌的发展路径。首先分析了“景漂”与景德镇陶瓷文化的内在关系,从实践角度探讨了“景漂”创业过程中摆地摊、陶瓷工作室和陶瓷公司三种组织形态。在此基础上,本文提出了以工作室为依托的初创陶瓷文化创意品牌路径构建,从品牌背景和市场分析、作品差异化与品牌定位、品牌形象塑造等多个方面提出建议。

流浪者——Kawasaki VN1500 Drifter

它的风格与其他车厂的巡航车截然不同。超长的车身、宽阔的车把、漆黑的部件、巨大的前后挡泥板几乎覆盖了整条车轮，再加上“鲨鱼尾”般的消音器，这种突出的风格立刻抓住了人们的目光，它莫非是失落多时的巡航车鼻祖——印地安。应该说是印地安式的，是来自日本的Keweseki VN1500 Drifter(浪人)。

基于场所精神理论的城市社区图书馆漂族老人服务策略研究--以北京市社区为例

随着我国城市化进程的加快和老龄化社会的来临,一个特殊群体“老漂族”诞生,且总量越来越大。他们的城市生活举步维艰,是等待全社会关爱的孤独弱势群体。社区图书馆作为公益性的服务社区的基础空间场所,应为老漂群体提供服务。文章借助场所精神理论,通过对北京多个小区的漂族老人进行调查,提出存在的问题,分析其生活现状与特点,从而有针对性地提出社区图书馆面向漂族老人的构建策略,整合场所精神要素,打造面向漂族老人的公共文化空间,使其产生精神认同感,实现自我价值进而找到情感归属。

社区建成环境对“老漂族”幸福感的影响研究

在人口流动和老龄化加剧的双重驱动下,“老漂族”群体正在不断壮大。由于“老漂族”兼具老年和流动的特征,他们受物质空间变化以及脱离原有的社会关系进入到相对陌生的环境的影响,在城市生活和融入等方面存在更多问题,这也使得了解“老漂族”的心理健康状态有着很大的现实意义。因此,以社区生活圈为单元,通过调研南京市20个社区,运用logistic回归模型,探究社区建成环境对于“老漂族”主观幸福感的影响。研究发现:行为活动特征、社区融入度以及主客观建成环境均对“老漂族”主观幸福感产生显著影响;公园绿地、药店和中学密度等客观建成环境对“老漂族”的主观幸福感有积极影响;“老漂族”具有空间偏好性,其行为活动更加倾向于公共性更强的大型公园绿地。