首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
太平洋海域海气热通量地理分布和时间变化的研究   总被引:6,自引:1,他引:6  
应用美国宇航局Goddard地球观测系统四维资料同化系统计算和分析了太平洋海域感热通量和潜热通量随时间的变化规律和地理分布特征.研究结果表明,太平洋西北部海域热通量有明显的季节性变化,其余海域这种现象不明显.在太平洋海域总是存在潜热通量最高值区域,而感热通量除冬季20°N以北海域数值稍高外,其余海域数值都很小,没有出现最高值区域.纬度不同热通量随经度的变化规律不同,经度不同,热通量随纬度的分布规律也不同,同时各断面热通量随纬度的分布趋势随季节而改变.  相似文献   

2.
中西太平洋金枪鱼围网高产渔区年间变化及其原因分析   总被引:1,自引:1,他引:0  
金枪鱼类是中西太平洋海域重要的经济鱼种,其中鲣产量约占到总产量的50%。本研究利用1995-2010年16年的中西太平洋(20°S~20°N,120°E~155°W)鲣围网生产统计数据和Niño3.4海区(5°S~5°N,120°~170°W)海表温度异常数据,对这16年鲣产量最高的十大渔区(5°×5°)进行时空格局分析,讨论渔场分布差异及CPUE与ENSO指数的关系。结果表明:16年间十大作业渔区主要分布在5°S~5°N、130°~175°E区域,这十大渔区产量占总产量的比重达47.5%,其中5°S~0°、155°~160°E,0°~5°N、130°~135°E,0°~5°N、135°~140°E及5°S~0°、160°~165°E等4个渔区产量占高产渔区产量的比重均超过10%,是中西太平洋重要的鲣产区。高产渔区的分布受海表温度影响较大,在厄尔尼诺时期,高产渔区分布明显偏东,主要分布在155°~180°E海域;在拉尼娜时期,高产渔区分布明显偏西,主要分布在130°~160°E海域。  相似文献   

3.
长江口外低氧区特征及其影响研究   总被引:2,自引:0,他引:2  
通过对2008年8月至2010年9月在长江口30°20′N~32°30′N,122°15′E~124°20′E范围海域开展的7次综合海洋调查资料进行分析,以期了解长江口海域低氧现象的年际、季节变化及其对海洋环境和生物的影响。研究结果发现,该海域夏季存在长江口和浙江南部两处低氧区域,低氧现象主要发生在20~50?m水层;低氧海域与非低氧海域的无机氮(DIN)、活性磷酸盐、叶绿素a含量存在一定差异;长江口海域浮游动物、浮游植物的分布状况与低氧区的存在与否未能发现相关关系。低氧区是底栖生物生物量的高值区,多毛类是其中最多的底栖生物种类,对低氧环境的耐受程度较高。  相似文献   

4.
利用印度气象局(India Meteorological Department,IMD)、国际气候管理最佳路径档案库(International Best Track Archive for Climate Stewardship,IBTrACS)提供的1982—2020年阿拉伯海热带气旋路径资料,美国国家环境预报中心(National Centers for Environmental Prediction,NCEP)再分析资料,对近39 a阿拉伯海热带气旋源地和路径特征、活跃区域、频数及气旋累积能量(accumulated cyclone energy,ACE)指数的季节特征和年际变化特征进行分析,并结合环境因素,说明其物理成因。结果表明:阿拉伯海热带气旋多发于10°~25°N,65°~75°E海域,5—6月、9—12月发生频数较高且强度较强,1—4月、7—8月发生频数较低且气旋近中心最大风速均小于35 kn;频数的季节变化主要受控于垂直风切变要素;阿拉伯海热带气旋发生频数和ACE近年有上升趋势,年际变化主要受控于海面温度(sea surface temperature,SST)和850 hPa相对湿度要素。  相似文献   

5.
热带东印度洋-西太平洋海域OLR季节内振荡空间分布特征   总被引:5,自引:0,他引:5  
利用卫星观测的OLR(Outgoing Longwave  Radiation)候平均资料(1979-1993年)分析热带东印度洋-西太平洋海域大气对流季节内振荡的空间分布特征。发现热带东印度洋-西太平洋海域(35°N-35°S,75°E-180°E)大气对流运动的季节内振荡在4个区域中表现较明显:(1)热带东印度洋大气对流季节内振荡信号最强,显著的振荡周期集中在6.5-12.5候;(2)澳大利亚西北洋面季节内振荡强信号主要周期表现为9.5-15.5候;(3)澳大利亚东北洋面振荡周期集中在6.5-9.5候和9.5-15.5候,南半球的大气对流活动季节内振荡显著区沿10°S呈纬向带状分布;(4)南海北部、吕宋海峡附近及日本群岛以南的西北太平洋区域。ISO振荡周期集中在6.5-12.5候,南海南部季节内振荡周期集中在6.5-15.5候。  相似文献   

6.
采用主分量分析法(PCA)对中国东南部(105°—122°E,19°—33°N)90个测站(除台湾省外)1954—1989年逐年1,4,7,10月降水量标准化资料进行分解,得到各种异常降水型及相应的时变序列;对最为典型的3种异常降水型的空间分布特点、时变特征、逐年分型情况进行了分析,并探讨了各月各异常降水型变化与赤道东太平洋海面温度变化间的可能关系及它们在厄尔尼诺年份(或次年)的一些特点和规律。  相似文献   

7.
利用SODA数据分析了20世纪70年代气候跃迁前后热带太平洋温跃层变化的季节特征,研究了NCEP/NCAR再分析资料中的风场变化与温跃层变化之间的关系。研究结果表明:1)在1976—1977年气候跃迁之后,温跃层深度存在显著的年代际变化。在热带太平洋东部的秘鲁沿岸海域温跃层变深,而在10°S~10°N的热带太平洋其他海域温跃层均呈现变浅趋势;2)温跃层深度的年代际变化存在显著的季节差异。总体表现为,温跃层变浅的最显著区域随着季节的推移由东太平洋逐渐移至西太平洋并且变浅的幅度增大;3)热带太平洋海表面风场的年代际变化导致的赤道西风异常及风场异常的散度场是温跃层变化的主要原因。  相似文献   

8.
利用1992~2001年Topex/Poseidon卫星高度计遥感资料分析了太平洋东南海域 (5°~55°S ,70°~110°W)海面高度的季节及年际变化特征。研究结果表明 ,海区海面高度的季节变化总体上受太阳辐射季节变化的影响 ,南半球夏季 (1~3月 )和秋季 (4~6月 )大致为正距平 ,而冬季 (7~9月 )和春季 (10~12月 )大致为负距平 ,1996~1998年除外 ;同时 ,受季节性风场、海区罗斯贝波等的影响 ,海面高度变化的区域特征性很强。海面高度的年际变化在低纬处和沿岸还受ElNino影响。  相似文献   

9.
中西太平洋是全球主要的鲣鱼(Katsuwonus pelamis)围网作业渔场,渔场极易受到海洋环境的影响,但渔场分布在众多岛国的管辖海域,如何科学指导企业准确入渔是重要的研究课题。本文根据1995-2012年中西太平洋鲣鱼围网捕捞生产统计数据,选取产量最高的22个海区(5°×5°),结合Niño3.4区海表温度距平值(SSTA)和作业海域表温(SST),研究中西太平洋鲣鱼围网渔场的空间分布规律,同时,以各海区捕捞努力量(作业次数)所占的百分比为入渔指标,建立基于环境因子的入渔决策模型。研究认为,中西太平洋鲣鱼捕捞努力量在纬度方向上主要分布于5°S~5°N,其累计捕捞努力量占所有作业海区的87.4%,其中以130°~140°E经度范围为最高,其捕捞努力量占22个海区的45.08%。入渔指标与Niño3.4区的SSTA、作业海域SST均符合正态模型(P<0.01),Niño3.4区的SSTA最适值为0.25℃,作业海域SST最适值在29.5℃左右。对预测和实际排名前十的海域进行统计发现,预测值与实际值基本一致。研究认为,所建立的入渔预测模型可有效指导企业的渔业生产,为提高企业生产效率提供支撑。  相似文献   

10.
利用1949~2004年共54 a的热带气旋资料,通过对历年影响我国近海(距海岸线300 n mile范围内)25°N以北及以南热带气旋的基本要素特征值的分析,发现我国近海25°N以北与以南热带气旋影响的频数和年代际变化不一致,尤其是20世纪80年代中期以来呈现反位相特征,近海25°N以北TC偏多,强度强;25°N以南TC偏少,强度弱.对热带气旋个数偏多年与偏少年对应的夏季海温场、高度场的合成分析,发现25°N以北偏多年比以南偏多年的东太平洋海温负距平强度大、范围广,高度距平场上反映出25°N以北偏多年西太平洋(包括南海)负高度距平区更为偏北、偏东;25°N以北TC偏少年时,中东太平洋海温为正距平区,高度场上太平洋低纬区域基本为正距平区,太平洋高纬区域是负距平区,而以南TC偏少年中东太平洋海温是负距平区,高度场上太平洋高纬区域是正距平区.文中还对当年前期各月海温场、高度场与当年以北、以南热带气旋个数分别作了相关分析,得出了一些实用有效的预报因子.  相似文献   

11.
-Mainly on the basis of the data obtained during PRC/US bilateral TOGA cruises, abnormal variation occurred during the 1986/1987 El Nino is shown in this paper about the thermal structure and circulation of the upper western tropical Pacific Ocean. The effects of the abmormal variation on the subtropical high over the Northwest Pacific Ocean are discussed. During the El Nino: (1) In the east part of the western tropical Pacific Ocean (the subsurface temperature data on the 165° E section are taken as an example), the water wanner than 29 C in the upper layer spread on the longitudinal section and positive temperature anormalies appeared in a large area of the sea surface. (2) In the west part of the western tropical Pacific Ocean (the subsurface temperature data on the 137°E section are representative ), the cross section occupied by the upper layer warmer water ( T >28 ℃ ) became shrunk, and the sea surface temperature showed negative amomalies. (3) The eastward flows in the upper layer of the 165°  相似文献   

12.
The long-term time series analysis of the SST (sea surface temperature) in the Eastern Equatorial Pacific Ocean and the monthly MSL (mean sea level) in the tropical Pacific Ocean is conducted. Their quasiperiodic and low-frequency oscillation features are revealed. The significant periods of low-frequency fluctuations for monthly MSL in the area of 20°N-20° S are between 43. 5 months and 50. 0 months, approximating closely to 47. 6 months which is the significant period of SST in the Eastern Equatorial Pacific Ocean. From the results of space-spectral analysis, the low-frequency fluctations of monthly MSL in the tropical Pacific Ocean appear to have a anticlockwise circularly-propagating pattern, which is, the Eastern Pacific Ocean (off-shore of Mexico) →the area of NEC (North Equatorial Current) →the Western Equatorial Pacific Ocean→the area of NECC (North Equatorial Counter-Current)→the Eastern Equatorial Pacific Ocean. The phases of the pattern correspond to those of El Nino cycle. On the basis  相似文献   

13.
北太平洋海温场的时空特征分析   总被引:1,自引:1,他引:1  
近年来运用海表温度作副热带高压和长期天气预报方面取得了显著效果,为了进一步探讨海洋对气候和长期天气过程的影响,必须重视海温场的特征分析。这几年已有一些工作[1,3,7],从不同侧面对北太平洋海温场进行研究。本文试图从海—气相互作用的角度分析北太平洋海温场的时空分布特征及其年际变动,进而讨论它们对大气的影响。  相似文献   

14.
Observations of the equilibrium partial pressure of carbon dioxide in the surface waters of the North Pacific Ocean and Bering Sea indicate conditions of local upwelling or vertical mixing near the Aleutian Island passes, seasonal depletion of CO2 in the sea surface by photosynthesis, and conditions of CO2 supersaturation in the surface waters off the mouths of large rivers. Horizontal mixing has a large effect on the PCO2 distribution. The area distribution of carbon dioxide in the surface waters of the Pacific Ocean from 19°N to 55°N latitude and in the Bering Sea is presented.  相似文献   

15.
西风爆发、次表层暖水东移与厄尔尼诺现象   总被引:7,自引:2,他引:7       下载免费PDF全文
利用最近20 a的大气海洋资料,分析了厄尔尼诺事件与赤道太平洋西风异常以及赤道太平洋次表层海温之间的关系.结果表明,赤道西太平洋(5°S~5°N,120°~160°E)和赤道中东太平洋(5°S~5°N,160°E~160°W)西风异常都存在着与厄尔尼诺周期一致的年际变化,但前者还包含有显著的2~3个月季节内振荡.赤道西太平洋次表层冷暖水东移也呈现年和年际时间尺度的振荡周期.在厄尔尼诺发生前,赤道西太平洋次表层海水出现持续性增暖,赤道西太平洋西风异常频率加快,强度增强.随后赤道中太平洋(160°E~160°W)出现持续性(3个月以上)强西风异常(即西风爆发),并进一步向东扩展,同时次表层暖水沿着赤道波导东移到赤道东太平洋混合层,导致赤道东太平洋海表大面积异常增暖,形成一次厄尔尼诺现象.最后,模式模拟了1980~1984年赤道太平洋海温的变化,进一步证实了赤道纬向西风异常对暖水东移起着重要的作用.  相似文献   

16.
中国近海海温年际年代际振荡关键海区分析研究   总被引:1,自引:0,他引:1  
用HADLEY中心的HadISST的海温资料、NCEP的大气资料、国家气象局发布的74个月平均环流指数和美国华盛顿大学的PDO指数,讨论研究了中国近海海温的年际年代际振荡。通过对我国近海海温的EOF分析,可以发现我国近海30 N附近是海温年际年代际振荡信号最强的关键区,它占了总量的58.2%,与澳大利亚东北沿海海温年代际振荡有相同的周期,最明显周期是44—45年,滞后PDO信号近15年左右。该关键区海温与澳大利亚东北沿海海温都还存在1年、5年和15年的振荡,它们的相关系数达到0.604,属于同一个模态。另外,1年的海温振荡信号除了澳大利亚东北沿岸以外,还沿着西太平洋海岸线分布,因此中国近海海温年际年代际振荡不是一种局地现象,而与太平洋海温变化有关。另外,它是海气相互作用的结果,与中高纬度的东亚大槽和低纬度太平洋印度洋的风场、西太平洋副高和南海副高、大气温度场甚至南半球环流有明显的关系。  相似文献   

17.
Using the air-sea data set of January, 1983 (the mature phase of the 1982/83 El Nino event), the net radiation on the sea surface, the fluxes of the latent and the sensible heat from ocean to the atmosphere and the net heat gain of the sea surface are calculated over the Indian and the Pacific Oceans for the domain of 35°N-35°S and 45°E-75°W. The results indicate that the upward transfer of the latent and the sensible heat fluxes over the winter hemisphere is larger than that over the summer hemisphere. The sensible heat over the tropical mid Pacific in the Southern Hemisphere is transported from the atmosphere to the ocean, though its magnitude is rather small. The latent heat flux gained by the air over the eastern Pacific is less than the mean value of the normal year. The net radiation, on which the cloud amount has considerable impact, is essentially zonally distributed. Moreover, the sea surface temperature (SST) has a very good correlation with the net radiation, the region of warm SST coinci  相似文献   

18.
An attempt to the approximate figures of seasonal distribution of solar energy reached to and penetrated in the water of the oceans, as a preliminary step to the estimation of primary production in the oceans from the optical point, was performed in the Indian Ocean, North Pacific Ocean and Antarctic Ocean on the same lines in the part III. In consequence, the total amount of solar energy for the year in each depth showed marked differences in each zone of the oceans as illustrated in Fig. 5. By way of example, it could be said that underwater solar energy already came to 33.4 Kg·cal/cm2·year in 10 m deep in the equator of Indian Ocean and was 54% of that, in the Kuroshio region of the North Pacific Ocean, 44% in the Sub-Antarctic zone, 13% in the Antarctic zone and 6% in the Antarctic Convergence zone, respectively. Besides, on the assumption that a lower limit of the photic zone is marked by the depth here underwater surface solar energy is reduced to 1% or 5g·cal/cm2·day, the ratio of the total photic zone for the year in unit area of sea surface was approximately 100∶80∶60∶25 or 100∶75∶50∶20 in the equator of the Indian Ocean, Kuroshio region, Sub-Antarctic zone, and Antarctic and Antarctic Convergence zones, respectively.  相似文献   

19.
1Introduction Sulfurisoneofthemostimportantelements whosebiogeochemicalcyclesarepivotaltotheatmo- sphericenvironmentandtotheclimaticchanges.The predominant,stablechemicalspeciesofsulfurinthe atmosphereissulfuricacidorsulfatewhichunderor- dinaryconditionsexistsmainlyinsmallaerosolparti- cles(Chinetal.,1996;Kerminenetal.,2000;Restadet al.,1998).Sulfuricacidorsulfate-dominatedaerosols areubiquitousintheloweratmosphere.Inthemarine boundarylayer(MBL),non-sea-saltsulfuricacidorsulfate(nss-SO42-)…  相似文献   

20.
The S/V Shoyo, of the Hydrographic Department, Japan Coast Guard, has conducted high-density expendable bathythermograph (XBT) measurements along the 32.5°N line in the North Pacific every year from 1990 to 1993 as a part of the Japanese-World Ocean Circulation Experiment (WOCE). These XBT data are analyzed here, focusing on year-to-year variations of the inventory and core layer temperature (CLT) of the North Pacific subtropical mode water (NPSTMW). Large year-to-year changes are found in the NPSTMW CLTs estimated in longitudes between 140°E and 160°E. CLT values were found of 17.4°C in 1990, 17.1°C in 1991, 17.3°C in 1992 and 17.6°C in 1993. Inspection of the wintertime westerlies over the formation area and sea surface temperature distribution revealed that this change in CLT can be qualitatively attributed to the strength of atmospheric cooling in the formation area in the previous winter. Although a large year-to-year variation of NPSTMW inventory was also found, it is hard to state any relationship between CLT and atmospheric forcing. There is a possibility that different observational seasons may affect the inventory. It has also been found that the thermocline depth in 1991 was shallower in the sea area east of 180° than in 1992 and 1993. Associated with this change, the North Pacific central mode water (NPCMW), characterized by thermostad with temperatures ranging from 14°C to 11°C, appears in the sea area east of 180° in the 1992 and 1993 cross sections. The 1993 cross section, which ranged from the Japanese coast to the west coast of North America, possessed another thermostad in the surface layer, with a temperature of about 17°C in the eastern part of the cross section, off California. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号