基于TIGGE资料的北半球地面气温预报的统计降尺度研究

基于TIGGE(THORPEX Interactive Grand Global Ensemble,全球交互式大集合)资料中欧洲中期天气预报中心(European Centre for Medium-Range Weather,ECMWF)、日本气象厅(Japan Meteorological Agency,JMA)、美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)和英国气象局(United Kingdom Met Office,UKMO)4个中心的北半球地面2 m气温集合平均预报资料,利用插值技术与回归分析,并引入了消除偏差集合平均(bias-removed ensemble mean,BREM)和多模式超级集合(superensemble,SUP)方法进行统计降尺度预报研究。结果表明,在2007年夏季3个月中,4个单中心的降尺度预报明显地改善了预报效果。引入SUP和BREM两种集成预报方法后,预报误差得到进一步减小。对比综合表现最好的单中心ECMWF的预报,1~7 d的降尺度预报误差改进率均达20%以上。研究还发现,引入SUP方法的降尺度预报效果优于引入BREM方法的降尺度预报,利用双线性插值方法在上述两方案中的预报效果优于其他3种插值方法。     

资料均一化对沈阳站气温趋势和城市化偏差分析的影响

利用国家气象信息中心2013年发布的逐日均一化气温资料,对沈阳站资料均一化处理前后平均气温和极端气温指数序列的线性趋势及其城市化影响偏差进行了比较评价。结果表明:1)资料均一化处理对日最高气温及其衍生的极端气温指数序列趋势估计的影响较弱,但对日最低气温及其衍生的极端气温指数序列趋势估计具有显著影响。2)经资料均一化处理后,平均气温序列中的城市化影响偏差有所增大,平均最低气温序列中的城市化影响偏差增大尤其明显;与冷事件有关的极端气温指数序列的城市化影响偏差数值有所减小,与暖事件有关的极端气温指数序列的城市化影响偏差数值有所增加。3)资料均一化处理有效纠正了因迁站等原因造成的地面气温观测记录中的非均一性,但却在很大程度上还原了城市站地面气温观测记录中的城市化影响偏差。     

三疣梭子蟹(Portunus trituberculatus)胞内氯离子通道蛋白基因克隆及其表达分析

本研究克隆了三疣梭子蟹(Portunus trituberculatus)胞内氯离子通道蛋白基因,命名为Pt CLIC。该基因c DNA全长2000bp,5’和3’非编码区(UTR)长分别为76bp和1162bp,开放阅读框长762bp,推测编码253个氨基酸,预测分子量为29.2k Da,理论等电点为5.93。生物信息学分析表明,Pt CLIC基因中未发现跨膜结构域,属于不稳定蛋白;同源性分析表明,Pt CLIC基因编码的氨基酸序列与蚤状溞(Daphnia pulex)CLIC基因的同源性高达83%;系统进化分析表明,三疣梭子蟹与拟穴青蟹首先聚为一支;实时荧光定量RT-PCR分析表明,Pt CLIC基因在选取的所有组织中均有表达,在肝胰腺中的相对表达量最高,且显著高于其它组织(P0.05)。低盐度胁迫显著改变了Pt CLIC基因在三疣梭子蟹鳃和肝胰腺中的表达模式,整体呈先上调后下调的趋势,并发现该基因在低盐耐受和低盐敏感家系中的表达规律差异显著。研究结果表明Pt CLIC基因在三疣梭子蟹渗透压调节中发挥重要作用,可辅助三疣梭子蟹耐低盐品系的选育。     

基于阈值区间的海洋锋面提取模型

A model （Bayesian oceanic front detection, BOFD） of sea surface temperature （SST） front detection in satel- lite-derived SST images based on a threshold interval is presented, to be used in different applications such as climatic and environmental studies or fisheries. The model first computes the SST gradient by using a Sobel algorithm template. On the basis of the gradient value, the threshold interval is determined by a gradi- ent cumulative histogram. According to this threshold interval, front candidates can be acquired and prior probability and likelihood can be calculated. Whether or not the candidates are front points can be deter- mined by using the Bayesian decision theory. The model is evaluated on the Advanced Very High-Resolution Radiometer images of part of the Kuroshio front region. Results are compared with those obtained by using several SST front detection methods proposed in the literature. This comparison shows that the BOFD not only suppresses noise and small-scale fronts, but also retains continuous fronts.     

Genetic parameter estimation for juvenile growth and upper thermal tolerance in turbot (Scophthalmus maximus Linnaeus)

Twenty-six half-sib groups(53 full-sib families) of turbot, Scophthalmus maximus Linnaeus, were obtained by artificial insemination. We measured growth in the offspring(40–50 individuals/family) and subjected them to a thermal tolerance challenge over a period of 34 d. There was no significant difference in daily mortality(range: 0.580%–1.391%) between Days 1–13 during the thermal tolerance challenge. However, daily cumulative mortality increased rapidly between Days 14 and 29, especially on Days 15 and 16(20.232% and 34.377%, respectively). Mortality was highest on Day 16(14.145%). We estimated the genetic parameters using the average information restricted maximum likelihood method. We used a likelihood ratio test to evaluate the significance of effects in models with and without identity as an effect, and compared the final log-likelihoods(maximum log L). Lastly, we estimated phenotypic and genetic correlation between the upper thermal tolerance limit(UTT) and body weight(BW). In this study, the positive phenotypic correlation was low between UTT and BW(0.093±0.029). The genetic correlation between UTT and BW was negative(-0.044±0.239). The heritability for upper thermal tolerance was low(0.087±0.032), which is of approximately moderate heritability. The heritability for body weight was high(0.303±0.074). Our results suggest there is significant potential for improvement in the culture of turbot by selective breeding.     

温度和光径对微绿球藻生长及营养成分含量的影响

研究了温度和光生物反应器的光径对微绿球藻(Nannochloropsis oculata Hibberd)生长及细胞内几种营养成分含量的影响。结果表明,温度对微绿球藻的生长有显著影响(P0.05),对几种营养成分的含量有极显著影响(P0.01),在28℃的培养条件下,细胞生长速度最快,此时蛋白质含量最高,为5.66%,多糖含量最低,仅为1.47%,但最大生物产量却是在30℃的条件下获得,总脂与叶绿素a的含量随温度的升高而降低,类胡萝卜素含量随温度升高而增大。光生物反应器的光径对微绿球藻的生长和总脂、可溶性蛋白、色素的含量有极显著影响(P0.01),对多糖含量有显著影响(P0.05),比生长速率、最高细胞密度和单位体积产量均随光径的增大而减小,单位面积产量随光径的增大而增大;总脂、可溶性蛋白和多糖的含量随光径的增大而降低,叶绿素和类胡萝卜素含量随光径增大而增大,类胡萝卜素含量的增大趋势比叶绿素更明显。     

黄海冷水团海域微型异养鞭毛虫与细菌的弱耦合关系

A study was carried out to investigate the grazing pressure of heterotrophic nanoflagellates(HNF) on bacteria assemblages in the Yellow Sea Cold Water Mass(YSCWM) area in October, 2006. The results show that the HNF abundance ranges from 303 to 1 388 mL-1, with a mean of 884 mL-1. The HNF biomass is equivalent to 10.6%–115.6% of that of the bacteria. The maximum abundance of the HNF generally occurred in the upper 30 m water layer, with a vertical distribution pattern of surface layer abundance greater than middle layer abundance, then bottom layer abundance. The hydrological data show that the YSCWM is located in the northeastern part of the study area, typically 40 m beneath the surface. A weak correlation is found between the abundances of HNF and bacteria in both the YSCWM and its above water layer. One-way ANOVA analysis reveals that the abundance of HNF and bacteria differs between inside the YSCWM and in the above water mass. The ingestion rates of the HNF on bacteria was 8.02±3.43 h-1 in average. The grazing rate only represented 22.75%±6.91% of bacterial biomass or 6.55%+4.24% of bacterial production, implying that the HNF grazing was not the major factor contributing to the bacterial loss in the YSCWM areas.     

2013年海洋和大气环流异常及对中国气候的影响

本文对2013年海洋和大气环流异常特征进行分析,讨论这些异常特征对中国气温和降水的主要影响。结果表明：2012/2013年冬季,北极涛动持续维持负位相,500 hPa位势高度场上,欧亚大陆中高纬环流呈“两槽一脊”的环流形势,乌拉尔山的高压脊持续偏强,而东亚槽也异常偏强,导致全国平均气温较常年同期偏低。季内,西伯利亚高压强度变化显著,与之相对应,我国气温季内阶段性变化大,前冬冷、后冬暖。进一步研究表明,前秋北极海冰的大幅偏少是造成东亚冬季风偏强的重要原因。2013年冬季至夏季,赤道中东太平洋海温异常偏低而海洋性大陆至西太平洋海温异常偏高,受此影响,夏季西太平洋副热带高压位置明显偏北,导致我国北方夏季多雨。与此同时,受西太平洋副热带高压下沉气流的控制,我国南方大部高温持续。2013年南海夏季风爆发偏早两候,结束偏晚4候,强度偏弱。     

江苏—南黄海地区M≥6强震有序网络结构及其预测研究

基于TIGGE（THORPEX Interactive Grand Global Ensemble,全球交互式大集合）资料中欧洲中期天气预报中心（European Centre for Medium-Range Weather,ECMWF）、日本气象厅（Japan Meteorological Agency,JMA）、美国国家环境预报中心（National Centers for Environmental Prediction,NCEP）和英国气象局（United Kingdom Met Office,UKMO）4个中心的北半球地面2m气温集合平均预报资料,利用插值技术与回归分析,并引入了消除偏差集合平均（bias-removed ensemble mean,BREM）和多模式超级集合（superensemble,SUP）方法进行统计降尺度预报研究.结果表明,在2007年夏季3个月中,4个单中心的降尺度预报明显地改善了预报效果.引入SUP和BREM两种集成预报方法后,预报误差得到进一步减小.对比综合表现最好的单中心ECMWF的预报,1～7d的降尺度预报误差改进率均达20％以上.研究还发现,引入SUP方法的降尺度预报效果优于引入BREM方法的降尺度预报,利用双线性插值方法在上述两方案中的预报效果优于其他3种插值方法.