1321号台风“蝴蝶”强度变化特征和影响因素分析

利用NCEP/NCAR全球再分析格点资料（空间分辨率1°×1°）、台风实况资料及海南省气象台站观测资料,选取1321号台风＂蝴蝶＂为研究个例,从天气学原理高低空形势及动力、热力学物理量等多角度分析了＂蝴蝶＂强度演变特征及影响因素.研究结果表明,副热带高压与高空西风槽是影响此次台风的主要大尺度天气系统,弱冷空气南侵、南海海温偏高及越赤道气流强盛是＂蝴蝶＂迅速加强的重要原因.西风槽引导弱冷空气南侵使得台风外围环流气压梯度增加,斜压不稳定状态加剧;南海海温达到29℃,海温偏高使台风区域大气层结降低,深热对流发展;105°E越赤道气流强盛为台风提供了充沛水汽和能量.三者共同作用促使台风强度突然增强.另外,低层涡度、高层散度、湿位涡及水汽通量等物理量能够较好地表征＂蝴蝶＂强度变化特征.低层辐合流入、高层辐散流出为台风的加强提供了动力条件;湿位涡下负上正表明大气热力层结不稳定;水汽通量增加表明水汽条件充足.良好的动力条件、热力条件与水汽条件共同作用,使得＂蝴蝶＂在短时间内迅速加强为强台风.     

2003年西北太平洋热带气旋活动特征分析

本文综述了2003年西北太平洋上热带气旋活动特征，并对西北太平洋副热带高压特征量及赤道东太平洋海温与常年进行比较和相关分析，从而找出2003年西北太平洋热带气旋活动特征的成因。     

Interdecadal Variations of ENSO Signals and Annual Cycles Revealed by Wavelet Analysis

Interdecadal variations of El Niño/Southern Oscillation (ENSO) signals and annual cycles appearing in the sea surface temperature (SST) and zonal wind in the equatorial Pacific during 1950–1997 are studied by wavelet, empirical orthogonal function (EOF) and singular value decomposition (SVD) analyses. The typical timescale of ENSO is estimated to be about 40 months before the late 1970s and 48–52 months after that; the timescale increased by about 10 months. The spatial pattern of the ENSO signal appearing in SST also changed in the 1970s; before that, the area of strong signal spread over the extratropical regions, while it is confined near the equator after that. The center of the strongest signal shifted from the central and eastern equatorial Pacific to the South American coast at that time. These SST fluctuations near the equator are associated with fluctuations of zonal wiond, whose spatial pattern also shifted considerably eastward at that time. In the eastern equatorial Pacific, amplitudes of annual cycles of SST are weak in El Niño years and strong in La Niña years. This relation is not clear, however, in the 1980s and 1990s.     

南印度洋SST与南亚季风环流年代际变化的研究

利用美国NCEP全球大气再分析资料和JONES全球海表面温度异常(SSTA)资料，分析了南印度洋SSTA和南亚季风环流年代际变化的特征。研究发现，无论是南印度洋副热带海水辐合区的SST还是赤道以北非洲西海岸附近上升运动海区的SST的长期变化趋势，除了准3-5年的变化以外，还存在着明显的年代际的变化。对于全球最显著南亚季风环流的分析表明，南亚季风环流也存在明显的年代际时间尺度的变化。与南太平洋SST的年代际变化相比，南印度洋SST的变化周期要相对短一些。通过分析南半球冷空气年代际活动的特征发现，冷空气与南印度洋SST年代际时间尺度的变化具有密切的联系。     

Quality control methods for KOOS operational sea surface temperature products

Sea surface temperature SST obtained from the initial version of the Korea Operational Oceanographic System(KOOS) SST satellite have low accuracy during summer and daytime. This is attributed to the diurnal warming effect. Error estimation of SST data must be carried out to use the real-time forecasting numerical model of the KOOS. This study suggests two quality control methods for the KOOS SST system. To minimize the diurnal warming effect, SSTs of areas where wind speed is higher than 5 m/s were used. Depending on the wind threshold value, KOOS SST data for August 2014 were reduced by 0.15°C. Errors in SST data are considered to be a combination of random, sampling, and bias errors. To estimate bias error, the standard deviation of bias between KOOS SSTs and climatology SSTs were used. KOOS SST data yielded an analysis error standard deviation value similar to OSTIA and NOAA NCDC(OISST) data. The KOOS SST shows lower random and sampling errors with increasing number of observations using six satellite datasets. In further studies, the proposed quality control methods for the KOOS SST system will be applied through more long-term case studies and comparisons with other SST systems.     

与冬季北太平洋大范围海温异常相联系的海气特征

采用1948—2014年NCEP/NCAR大气再分析资料以及延伸重建海温资料,基于大气海洋间不同的主导关系对冬季北太平洋大范围海温异常进行分类,探究其相应的海气结构特征。结果表明:1)大气影响海洋的个例多于海洋影响大气的个例,即在冬季北太平洋大气强迫海洋占主要地位,但也存在海洋对大气的反馈作用。2)对于大气影响海洋而言,SST(Sea Surface Temperature)暖异常区上空主要伴随着东北—西南走向的相当正压高低压异常(东北高西南低),对应东南风异常以及显著的深厚暖异常,表现出相当正压暖/脊结构,冷异常情况与此相反。SST异常为净热通量异常与风速异常共同作用引起。3)对于海洋影响大气而言,在SST暖异常区上空西部为南北向高低压异常(北高南低),东部为低压异常,对应偏东风异常。在SST冷异常区上空为偶极型的南北向高低压异常(南高北低),对应偏西风异常;位势高度异常表现出相当正压结构且较大气影响海洋时相对偏弱,大气暖(冷)温度异常比较浅薄且主要局限于对流层低层。4)海洋温度结构异常主要表现为,在大气影响海洋时海温异常由表层下传,海洋影响大气时为上下一致的温度异常。     

Comparative ecology of the copepods Calanoides carinatus and Calanus agulhensis — the influence of temperature and food

Hypotheses regarding temperature, food abundance and food size were tested to explore niche separation between Calanoides carinatus, an abundant copepod in the cool and food-rich southern Benguela upwelling system, and Calanus agulhensis, the dominant copepod on the warmer, relatively food-poor Agulhas Bank off the south coast of South Africa. Under non-limiting food conditions, egg production by both species increased linearly with temperatures between 9°C and 18°C. Egg production by C. carinatus was relatively faster at 21°C, but was offset by greater mortality. Both species showed similar functional responses to food concentration in the field, reaching satiation at ～15mg Chl a m^?3, or ～3–4ppm. Food abundance was the most important predictor of egg production, whether measured as Chl a or as particle volume. Both species preferred larger particles that dominated the biomass peak, but particle size appeared more important for C. carinatus, with increasingly faster rates of egg production as the proportion of large cells (>10μm) exceeded 50%, and slower ingestion of small (<10μm) cells. Omnivory may be more important to C. agulhensis. Niche separation between the two species appears unrelated to temperature, food abundance or diel vertical migratory behaviour, and is more likely a function of variability in food availability, although food size may also play a role.     

东、黄海海表面温度季节内变化特征的EOF分析

基于1998—2004年的TRMM/TMI卫星遥感海面温度(SST)数据,在初步分析东、黄海SST的季节分布特征的基础上,采用EOF方法分析了SST的季节内变化特征,进而对SST季节内变化的可能机制进行了探讨。EOF分析获得的前4个模态的累积方差贡献率为57.07%,其结果基本反映了东、黄海SST变化的主要物理过程。其中,EOF的第一模态的方差贡献率占30.17%,其空间模态揭示了以东海北部为中心的、整个海域SST变化趋于一致的特征,这一模态的显著变化周期为6.3周;第二模态的方差贡献率占14.36%,其空间模态呈现东南海域与西北海域SST的反相变化趋势,显著变化周期为8.7周和10.6周;第三模态的方差贡献率占7.02%,其空间SST变率最大的区域位于黄海海域,显著变化周期为6.8,8.7,10.2周等;第四模态的方差贡献率占5.52%,其空间SST变率最大的区域位于东、黄海近海,显著变化周期为6.8周。东、黄海SST季节内变化与此海区大气中的季节内振荡是紧密相关的。     

基于印度洋海温信号的我国西北地区东部夏季降水组合降尺度预测方法研究

利用国家气候中心第二代气候模式预测业务系统(BCC-CPSv2)预测产品,引入印度洋海温信号,采用组合降尺度方法建立了西北地区东部汛期降水预测模型。该预测模型对1991—2017年西北地区东部夏季降水的回报技巧较BCC-CPSv2预测技巧显著提高,空间相关系数由0.42提高到0.75,均方根误差明显减小,最多下降达80%。预测模型对降水空间分布型的预测能力较好,很好地回报了典型年份（1987年和2010年）夏季的降水距平百分率分布。通过抓住气象变量的空间分布特征,组合降尺度方法可以修正动力模式产品的预测误差,为西北地区东部夏季降水预测提供科学依据和技术支持,具有较好的应用前景。     

Boulders or urchins? Selecting seeding sites for juvenile Haliotis midae along the Namaqualand coast of South Africa

The extent to which the relationship between juvenile abalone Haliotis midae and sea urchins Parechinus angulosus is induced by their physical habitat along the Namaqualand coast of South Africa was investigated. Correlation analyses between the proportion of abalone utilising sea urchins for refuge and the proportion of habitat defined as exposed were computed from 28 experimental seeding sites in Port Nolloth on the north-west coast of South Africa. A highly significant positive correlation was found (r = 0.72, p < 0.05). It was concluded that, along the Namaqualand coast, under-boulder habitat was the most important factor determining the survival of juvenile abalone (size 12–26mm). Site selection should therefore be based on the suitability of the physical substratum to provide shelter for juvenile abalone along that coast.