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1.
利用MHAT小波函数分析了湛江市近50年来年平均气温的多时间尺度变化特征,并采用Kalman滤波模型对年平均温度的变化趋势进行了预测研究。结果表明,在半个多世纪的气候变化过程中包含了16 a4、a和准2 a的周期振荡,20世纪80年代中期以来湛江气温持续升高,且未来几年仍处于偏高阶段。卡尔曼滤波模型对湛江年平均气温的预测中,独立样本预测的平均绝对误差(MAE)等于0.30℃,相对误差为1.24%,对短期气候预测工作具有较高的参考价值。  相似文献   

2.
利用时间序列经适当数学变换后生成的均生函数,建立了一个可用于长期气候变化趋势预测的数学模型,并将此模型用于四川地区年平均气温及年降水总量的历史拟合及预测。结果表明:模型对较长时间序列的多步预测有较好的效果。  相似文献   

3.
陕西近40年气候变化特征的分析   总被引:21,自引:2,他引:19  
利用陕西96个台站近40a气候资料,通过对气温和降水两个基本气象要素变化特征进行全面分析,得到陕西气候变化的一些特征。(1)近40a来,陕西平均气温在经历了20世纪60年代后期的低温后,从80年代中期开始有明显的上升趋势,陕北西部上升幅度最为明显;冬季平均气温明显上升,夏季平均气温有明显的降低趋势;极端气温明显上升,特别是90年代以后极端最低气温上升明显。(2)陕西平均年总降水量波动略有减少,自20世纪90年代以后冬季降水量增加明显,夏季降水量减少,尤其是关中西部增加明显。(3)年平均气温、季平均气温变化存在以1985年为跃变点,这次跃变比全国晚5~7a,比西北地区提前1a。  相似文献   

4.
根据历史文献和器测资料重建的气温和旱涝系列,对长江中游520年以来的气候变化特征进行诊断研究。结果表明:前400多年平均气温比后100年低0.37℃,20世纪前暖后冷趋势与全球增暖趋势相悖。  相似文献   

5.
广东汕尾近40年以来气温的变化特征   总被引:1,自引:0,他引:1  
根据汕尾地区汕尾、海丰、陆丰站1960—1999年的气温序列资料,采用线性趋势、累积距平、小波分析以及Mann-Kendall突变检验等方法对汕尾地区气温变化特征进行了分析,结果表明:40年来汕尾地区存在暖-冷-暖3个气候变化阶段。年季平均气温均呈上升趋势,尤其在1980年代中期以后升温更为明显;四季升温率以冬季最为显著。在不同冷、暖阶段,冷、暖年(季)出现的年数差异很大,其中异常冷年均出现在1980年前,异常暖年均出现在1990年后。年平均最高气温与最低气温同年平均气温一样均呈升高趋势。但不同站点的气温变化仍有一定差异。年平均气温汕尾站存在2—3a、6—7a、准12a周期,海丰站存在准7a与14—16a周期,陆丰存在准1.5a、准2.5a、5—7a、准16a周期,MK检验发现汕尾平均气温在1998年发生突变,其他两站的突变发生在1997年。  相似文献   

6.
利用MHAT小波变换分析和灰色拓扑预测方法对海南琼海1953—2007年55年的暴雨频次的变化特征进行分析,结果表明,暴雨频次分别存在2a、6a、8a的准周期变化,8a准周期在20世纪70年代初期和80年代初期的信号最强,但1990年代后,暴雨频次较降水量出现了更多的小尺度周期波动扰动,表明极端降水事件有频繁出现的趋势。暴雨频次的季节变化主要体现在夏秋两季的暴雨多发季节,夏季主要存在2a、6a、12—13a、18a左右的准周期,秋季主要存在2—3a、8—9a、12a、17—18a左右的准周期,并且在各个季节表现出多时间尺度交替的复杂结构变化的非周期性特征,能在一定程度上解释暴雨频次较为异常的状况。琼海大暴雨和特大暴雨主要发生在秋季原因,可能与西行热带气旋和南下弱冷空气共同影响海南岛,同时配合偏东回流的环流背景有很大关系。文中基于小波分析和灰色预测方法的研究结果,提供了琼海地区暴雨预报和防灾减灾的一定科学依据。  相似文献   

7.
提出了一种基于多元时间序列的Kn近邻短期气候预测模型。该模型既保留了Kn近邻算法的优良特性,同时又考虑了气候系统有关状态量之间的物理关系和动力行为特性。用该模型对云南各区域的平均月雨量距平值进行预测试验,其对云南1991年5月~1998年6月的月雨量距平值预测检验的距平符号相关准确率为63.5%,对云南1991~1998年的5月雨量距平值预测检验的距平符号相关准确率则可达到70.0%。该模型的建立具有一定的实际业务应用价值。  相似文献   

8.
紫红笛鲷随机扩增多态性DNA及遗传多样性分析   总被引:1,自引:0,他引:1  
采用RAPD技术分析了湛江近海紫红笛鲷(Lutjanus argentimaculatus Forskal)的遗传多样性。从120个随机引物中筛选出了14个引物。14个引物共检测到173个位点,其中多态位点比例(P)为68.79%,遗传距离(D)为0.2228,遗传多样性指数(日)为0.1904。结果表明,目前湛江近海的紫红笛鲷自然群体的遗传多样性仍然维持在良好水平,捕捞尚未对其造成明显影响。  相似文献   

9.
【目的】研究湛江地区降水的年际、年代际特征及其影响因素。【数据】基于1962-2016年湛江地区6个国家气象观测站的逐日降水资料、同期月平均ONI、PDO序列和月平均风场、相对湿度等再分析资料,【方法】结合线性倾向估计、连续小波变换、相关分析等多种统计学方法。【结果与结论】湛江地区降水存在准2 a、5~8 a的年际振荡,降水日数有显著的准40 a年代际振荡;夏、秋季节的降水变化构成了湛江地区全年降水变化的主要部分;除冬季降水量增加外,各季节降水与降水日数基本呈现"偏多-偏少"的年代际特征;进一步对比发现P1(降水偏多)时期涝年较多,旱年较少,P2(降水偏少)时期恰好相反,但严重涝年偏多,降水强度增大,极端性降水事件发生频次增多。通过对湛江地区降水可能产生影响的因素分析发现:P2时期湛江地区降水频次的减少主要是由于西北太平洋副热带高压的增强、西南季风的减弱以及夏、秋季孟加拉湾和中南半岛异常下沉气流影响所致;冬季南海东部低层异常气旋环流是P2时期降水增加的一个主要原因;P2时期ENSO、PDO等大尺度海气系统在调控湛江地区降水变化中所起作用均有增加。  相似文献   

10.
对国家气候中心1996年1~12月用T63模式所作的500hPa34次月延伸预报进行了检验评估,并对模式的系统性误差进行了分析和订正。在假定订正后的T63延伸预报完全准确的条件下,用ECMWF旬平均高度场和西南区域月平均气温和月雨量资料,建立了用T63预报产品预测西南区域月要素场的一种完全预报(PP)的动力统计关系。并对西南区域1996年2月至1997年1月逐月平均气温和降水进行了预报试验。  相似文献   

11.
12.
The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.  相似文献   

13.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprehensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose  相似文献   

14.
<正>Copyright Submfnion of a roanusatpt inks:that the work described has not been published before(exoept In the form of an abstrW or as part of a published lecture,review,or thesis);that it is not under consideration for publication elsewhere that its publication has been approved by ail  相似文献   

15.
<正>The Journal of Ocean University of China(Oceanic and Coastal Sea Research)is a comprehensive academic quarterly sponsored by the Ocean University of China,published one volume per year.This journal is devoted to the publication of the theoretical and applied research results on oceanography and marine fisheries.The fieldcovered include the physical,chemical,biological,geo-  相似文献   

16.
<正>The 35th IAHR World Congress was held in Chengdu,China from September 8 to September 132013.The title of the conference was:"The Wise Finds Pleasure in Water:Meandering through Water Science and Engineering".During the congress,1239 papers were presented in 139sessions for oral presentations and 7 sessions for poster presentations.After the Congress,a Committee was appointed to select some of the best papers presented at the Congress for publication,after a  相似文献   

17.
As an important component of the cryosphere,sea ice is very sensitive to the climate change.The study of the sea ice physics needs accurate sea ice thickness.This paper presents an electromagnetic-induction(EM) technique which can be used to measure the sea ice thickness distribution efficiently,and the successful application in Bothnian Bay.Based on the electromagnetic field theory and the electrical properties of sea ice and seawater,EM technique can detect the distance between the instrument and the ice/water interface accurately,than the sea ice thickness is obtained.Contrastive analysis of the apparent conductivity data obtained by EM and the value of drill-hole at same positions allows a construction of a transformable formula of the apparent conductivity to sea ice thickness.The verification of the sea ice thickness calculated by this formula indicates that EM technique is able to get reliable sea ice thickness with average relative error of only 12%.The statistic of all ice thickness profiles shows that the level ice distribution in Bothnian Bay was 0.4-0.6 m.  相似文献   

18.
Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

19.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

20.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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