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1.
应用海洋表层水温资料(COADS资料),分析研究了对全球气候有重要影响的热带西太平洋、印度洋海洋表层水温的年变化和年际变化的特性,探讨了与ENSO和南极冰面积变化之间的联系。结果表明,热带西太平洋及印度洋表层水温具有明显的年变化和年际变化而且它们之间存在不同的变化趋势。这种结果是两大洋的水温振荡周期不同有较大关系。热带印度洋表层水温的年际变化与E1 Ni ̄/no和La Ni ̄/na的发生年份存在较  相似文献   

2.
李淑瑶  崔红艳 《海岸工程》2022,41(2):162-172
基于北极海冰密集度、海冰范围、大气环流和海温数据,研究了1982—2001年与2002—2021年两阶段各20 a间北极秋季海冰的时空变化特征及其原因。结果表明,近20 a(2002—2021年)北极海冰密集度的下降中心由过去(1982—2001年)的楚科奇海及白令海峡一带,转移至亚欧大陆海岸的巴伦支海附近,且海冰范围每10 a减少量由0.44×106 km2增长至0.72×106 km2,减少速度加快约64%。秋季北极海冰范围与海水表面温度(Sea Surface Temperature,SST)、表面气温(Surface Air Temperature,SAT)及比湿(Specific Humidity)均呈显著负相关。2002—2021年的相关系数较1982—2001年有所提高,且与温度相关系数最高的月份提前了一个月。通过对海水表面温度、表面气温、比湿、气压场和风场的经验正交分解(Empirical Orthogonal Function,EOF)可知,1982—2001年间,北极地区的温度及比湿的上升中心集中在楚科奇海及白令海峡一带;2002—2021年间,上升中心则转移至巴伦支海一带。气压场和风场在前后两阶段也出现了中心转移的分布变化。北极地区大气与海洋环流各因素的协同变化影响着北极海冰的消融。  相似文献   

3.
Anomalous change of the Antarctic sea ice and global sea level change   总被引:3,自引:0,他引:3  
AnomalouschangeoftheAntarcticseaiceandglobalsealevelchange¥XieSimei;ZouBing;WangYiandBaoChenglan(1.NationalMarineEnvironmentF...  相似文献   

4.
-By using the sea surface temperature (SST) index of the Equatorial Pacific Ocean provided by Climate Analysis Center of U. S. A. , the numerical criteria of El Nino and La Nina events and their quantitative characteristics were calculated. Results show that the El Nino event was characterized with strong intensity, shorter life cycle and significant mature phase; however, the La Nina event has longer live cycle, weak intensity, insignificant mature phase. Through teleconnection analysis, it is found that the intensity index of SST over the Equatorial Pacific Ocean leads the intensity index of subtropical high by six months or so. During the El Nino years, the tropical cyclone over the northwestern Pacific is fewer than normal but stronger, and its genesis area shifts southeastward apparently; while in the La Nina years the number of tropical cyclones are larger.  相似文献   

5.
利用耦合了平板海洋模型的全球气候模式进行了大量的格林函数实验,以探究两极地区对于施加在中低纬度海域的热强迫的气候响应。结果表明,北极地区的气候不仅受到距离较近的北太平洋与北大西洋的影响,远离北极的热带太平洋以及南太平洋也对其气候有显著的影响,南极地区的气候则主要是受到邻近的南大洋的影响。通过经验正交函数法的进一步分析发现,北极响应最显著的区域包括波弗特海(Beaufort Sea)、拉普捷夫海(Laptev Sea)以及北极中心区附近;南极地区的响应主要集中在别林斯高晋海(Bellinsgauzen Sea)区域。另外,利用温度归因法对辐射反馈过程和大气能量输运分解发现,北极地区表面温度的响应主要是受到了反照率反馈以及垂直递减率反馈的影响,而南极地区的响应则主要是反照率反馈发挥了作用。  相似文献   

6.
本文利用1950-2015年间Hadley环流中心海冰和海温资料及NCEP/NCAR再分析资料,研究了热带太平洋海温异常对北极海冰的可能影响,并从大气环流和净表面热通量两个角度探讨了可能的物理机制。结果表明,在ENSO事件发展年的夏、秋季节,EP型与CP型El Niño事件与北极海冰异常的联系无明显信号。而La Niña事件期间北极海冰出现显著异常,并且EP型与CP型La Niña之间存在明显差异。EP型La Niña发生时,北极地区巴伦支海、喀拉海关键区海冰异常减少,CP型La Niña事件则对应着东西伯利亚海、楚科奇海地区海冰异常增加。在EP型La Niña发展年的夏、秋季节,热带太平洋海温异常通过遥相关波列,使得巴伦支海、喀拉海海平面气压为负异常并与中纬度气压正异常共同构成类似AO正位相的结构,形成的风场异常有利于北大西洋暖水的输入,同时造成暖平流,偏高的水汽含量进一步加强了净表面热通量收入,使得巴伦支海、喀拉海海冰异常减少。而在CP型La Niña发展年的夏季,东西伯利亚海、楚科奇海关键区受其东侧气旋式环流的影响,以异常北风分量占主导,将海冰从极点附近由北向南输送到关键区,海冰异常增加,而净表面热通量的作用较小。  相似文献   

7.
In this paper,by using the ECMWF objective analysed data as well as CAC and NOAA grid point data of 1981 and 1983,the sensible and latent heat fluxes at the air and sea boundary surface within the range of 45°E-75°W, 35°N-35°S over the Pacific and the Indian Ocean are calculated. The purpose is to analyse the different revealing features during the mature stage and at the end of the 1982 -1983 El Nino event and to compare the difference of the features between thd El Nino and the normal. The result shows that the air and sea heat exchange west of the dateline over the central tropical Pacific during the EJ Nino period is more intense than that of the normal. However,the fluxes of the sensible and latent heat on the sea surface with strong warming of SSTneat by and on the south side of the equator east of 170°W are low and even negative,and the patterns of the sensible and latent heat fluxes over the Indian Ocean during the year of 1983 are similer to that of normal. Spatial patterns of the sensible  相似文献   

8.
陈迪  孙启振 《海洋学报》2022,44(12):42-54
本文利用1951?2021年哈德莱中心提供的海冰和海温最新资料以及美国国家海洋和大气管理局气候预报中心提供的NCEP/NCAR再分析资料,分析探讨了北极海冰70余年的长期变化特征,进而研究了其快速减少与热带海温场异常变化之间的联系,揭示了在全球热带海洋海温场变化与北极海冰之间存在密切联系的事实。结果表明,北极海冰异常变化最显著区域出现在格陵兰海、卡拉海和巴伦支海。热带不同海区对北极海冰的影响存在明显时滞时间和强度差异,热带大西洋的影响相比偏早,印度洋次之,太平洋偏晚。热带大西洋、印度洋和中东太平洋海温异常影响北极海冰的最佳时间分别是后者滞后26个月、30个月和34个月,全球热带海洋影响北极海冰的时滞时间为33个月。印度洋SST对北极海冰的影响程度最强,其次是太平洋,最弱是大西洋。全球热带海洋对北极海冰的影响过程中,热带东太平洋和印度洋起主导作用。当全球热带海洋SST出现正(负)距平时,北极海冰会出现偏少(多)的趋势,而AO、PNA、NAO对北极海冰变化起重要作用,是热带海洋与北极海冰相系数的重要“纽带”。而AO、PNA和NAO不仅受热带海洋SST的影响,同时也受太平洋年代际振荡PDO和大西洋多年代际AMO的影响,这一研究为未来北极海冰快速减少和全球气候变暖机理的深入研究提供理论支撑。  相似文献   

9.
Arctic sea ice cover has decreased dramatically over the last three decades. This study quanti?es the sea ice concentration(SIC) trends in the Arctic Ocean over the period of 1979–2016 and analyzes their spatial and temporal variations. During each month the SIC trends are negative over the Arctic Ocean, wherein the largest(smallest) rate of decline found in September(March) is-0.48%/a(-0.10%/a).The summer(-0.42%/a) and autumn(-0.31%/a) seasons show faster decrease rates than those of winter(-0.12%/a) and spring(-0.20%/a) seasons. Regional variability is large in the annual SIC trend. The largest SIC trends are observed for the Kara(-0.60%/a) and Barents Seas(-0.54%/a), followed by the Chukchi Sea(-0.48%/a), East Siberian Sea(-0.43%/a), Laptev Sea(-0.38%/a), and Beaufort Sea(-0.36%/a). The annual SIC trend for the whole Arctic Ocean is-0.26%/a over the same period. Furthermore, the in?uences and feedbacks between the SIC and three climate indexes and three climatic parameters, including the Arctic Oscillation(AO), North Atlantic Oscillation(NAO), Dipole anomaly(DA), sea surface temperature(SST), surface air temperature(SAT), and surface wind(SW), are investigated. Statistically, sea ice provides memory for the Arctic climate system so that changes in SIC driven by the climate indices(AO, NAO and DA) can be felt during the ensuing seasons. Positive SST trends can cause greater SIC reductions, which is observed in the Greenland and Barents Seas during the autumn and winter. In contrast, the removal of sea ice(i.e., loss of the insulating layer) likely contributes to a colder sea surface(i.e., decreased SST), as is observed in northern Barents Sea. Decreasing SIC trends can lead to an in-phase enhancement of SAT, while SAT variations seem to have a lagged in?uence on SIC trends. SW plays an important role in the modulating SIC trends in two ways: by transporting moist and warm air that melts sea ice in peripheral seas(typically evident inthe Barents Sea) and by exporting sea ice out of the Arctic Ocean via passages into the Greenland and Barents Seas, including the Fram Strait, the passage between Svalbard and Franz Josef Land(S-FJL),and the passage between Franz Josef Land and Severnaya Zemlya(FJL-SZ).  相似文献   

10.
In this paper, on the basis of the observational hydrographic data obtained from the eighth cruise of PRC-USA bilateral air-sea interaction program, and combined with the sea surface temperature (SST) charts provided by NOAA, the data obtained from moored thermistor chains supplied by L. J. Mangum and sea level data provided by K. Wyrtki, the ocean conditions since October, 1989 in the western tropical Pacific are exposed, which indicate that 1990 is a year with weak El Nino event similar to the 1980 El Nino event, and the North Equatorial Countercurrent (NECC) has made a good contribution to the propagation of warm water from the Western to the Central and Eastern Pacific, a characteristic similar to that of the 1976 El Nino event. The 1990 weak El Nino event will soon fall into decay.  相似文献   

11.
1 INTRoDUcTIONThe study results from Nov. 1986 to Aug. 1990 in sea area (ll5"E - 165"E, 20"N -l0"S) during TOGA experiments, indicated that there were outstanding responses of differenceof partial pressure of CO, between sea and air (APCO,) and total dissolved concentrationof CO, (TCO,) to El Nino and La Nina in NW region of the Western Tropical Pacific,including the cruise lines from ll4ofy 22"N to l30"E, l8"N and that from l8"N to 8"N,along l30"E. The characteristics of dis…  相似文献   

12.
Teleconnection between El Nino/La Nina-Southern Oscillation (ENSO) phenomenon and anomalous Antarctic sea-ice variation has been studied extensively.In this study,impacts of sea surface temperature in the Indian Ocean on Antarctic sea-ice change were investigated during Janaury 1979 and October 2009.Based on previous research results,sea areas in the western Indian Ocean (WIO;50°–70°E,10 °–20 °S) are selected for the resreach.All variables showed 1-10 year interannual timescales by Fast Founer Tranaform (FFT) transformation.Results show that i) strong WIO signals emerged in the anomalous changes of Antarctic sea-ice concentration;ii) significant positive correlations occurred around the Antarctic Peninsula,Ross Sea and its northwest peripheral sea region iii) negative correlation occurred in the Indian Ocean section of the Southern Ocean,Amundsen Seas,and the sea area over northern Ross Sea;and iv) the atmospheric anomalies associated with the WIO including wind,meridional heat flux,and surface air temperature over southern high latitudes were the possible factors for the teleconnection.  相似文献   

13.
用EOF分析方法对北太平洋及赤道太平洋地区1949~1979年31年海表面温度距平场进行分解,得到几个主要距平海温模态(EOF1~3),分析了EOF1~3的时空分布特征。得到海温距平场的EOF1和EOF2~3模态分别对E1—Nino事件和黑潮大弯曲有很显著的相关性,指出SST第三模态场对黑潮大弯曲的影响具有很好的持续性,持续时间为1~2年。最后讨论了相互的影响过程,为黑潮大弯曲和E1—Nino事件的预报的可能性提供了依据。  相似文献   

14.
厄尔尼诺现象对广西海洋捕捞产量的影响   总被引:1,自引:0,他引:1  
厄尔尼诺现象是一种对世界渔业有重要影响的气候事件,它的形成,使得海洋气候、水温、海流等因子也相应发生了不同的变化。本文对1980-2009年的Nino3.4区的海表温度(SST)和广西海洋捕捞产量的增长率进行了线性回归并经F检验分析,得出了它们在α=0.05的水平上回归效果显著的结论(F>Fα=0.05),且随着厄尔尼诺强度的增强、持续时间的增长,广西海洋捕捞产量的增长率也随之增大。因此,可将Nino3.4区的海表温度作为预测广西海洋捕捞产量的一个重要指标。  相似文献   

15.
SouthernOscillationforcedbyheatsourceandtopographyQianWeihong,YouXintian(ReceivedJune5,1996,acceptedDecember9,1996)Abstract──...  相似文献   

16.
北极各海域海冰覆盖范围的变化特征   总被引:2,自引:1,他引:1  
Sea ice in the Arctic has been reducing rapidly in the past half century due to global warming.This study analyzes the variations of sea ice extent in the entire Arctic Ocean and its sub regions.The results indicate that sea ice extent reduction during 1979–2013 is most significant in summer,following by that in autumn,winter and spring.In years with rich sea ice,sea ice extent anomaly with seasonal cycle removed changes with a period of 4–6 years.The year of 2003–2006 is the ice-rich period with diverse regional difference in this century.In years with poor sea ice,sea ice margin retreats further north in the Arctic.Sea ice in the Fram Strait changes in an opposite way to that in the entire Arctic.Sea ice coverage index in melting-freezing period is an critical indicator for sea ice changes,which shows an coincident change in the Arctic and sub regions.Since 2002,Region C2 in north of the Pacific sector contributes most to sea ice changes in the central Aarctic,followed by C1 and C3.Sea ice changes in different regions show three relationships.The correlation coefficient between sea ice coverage index of the Chukchi Sea and that of the East Siberian Sea is high,suggesting good consistency of ice variation.In the Atlantic sector,sea ice changes are coincided with each other between the Kara Sea and the Barents Sea as a result of warm inflow into the Kara Sea from the Barents Sea.Sea ice changes in the central Arctic are affected by surrounding seas.  相似文献   

17.
厄尔尼诺期间和后期南海海面温度的两次显著增暖过程   总被引:5,自引:0,他引:5  
通过分析ICOADS海洋气象资料,结合ISCCP短波辐射和OISST海面温度,研究并探讨了ENSO等大尺度海气相互作用过程背景下南海海表面温度(SST)的年际变化。研究表明,南海SSTA的年际变化和ENSO关系密切,并且分为两个阶段。以增暖事件为例,在厄尔尼诺(El Nino)发生年的冬季和消亡年的夏季,南海出现了两次显著增暖。第一次增暖出现在El Nino盛期,是El Nino影响的一部分,这时南海云量减少,净太阳辐射通量增加,SST上升。第二次增暖出现在El Nino结束后的夏季,不是El Nino直接作用的结果;这时夏季风减弱,一方面使得海洋的潜热损失减少,另一方面减弱了越南东部沿岸的上升流,两者的共同作用导致SST增加。  相似文献   

18.
南极海冰的长期变化趋势   总被引:1,自引:0,他引:1  
解思梅  邹斌 《海洋预报》1996,13(3):21-29
本文使用了WDC-A提供的按WMO标准格式化的SGRID海冰资料和NSIDC提供的SMMR和SMM/1的亮温微波资料,将这些资料同化处理使海温序列延长为1973-1994年。利用上述资料研究海冰的长期变化趋势,发现70年代前期海冰迅速增多到中期达最大值,后期到80年代前期迅速减少到最少,80年代海冰持续偏少或在平均值附近振动,90年代前期海冰又开始缓慢增多。  相似文献   

19.
南极海冰和陆架冰的变化特征   总被引:8,自引:1,他引:8       下载免费PDF全文
利用美国冰中心和雪冰中心提供的海冰资料和我国南极考察现场的海冰观测资料,对南极海冰的长期变化进行了研究.研究表明20世纪70年代后期是多冰期;80年代是少冰期;90年代南极海冰属于上升趋势,后期偏多,区域性变化差别大,东南极海冰偏多,西南极海冰即南极半岛两侧尤其是威德尔海区和别林斯高晋海的冰明显偏少.东南极和西南极海冰的变化趋势总是反相的.90年代后期普里兹湾的海冰明显偏多,南极大陆陆架冰外缘线总体没有明显的收缩,有崩解也有再生的自然变化现象.西南极威德尔海的龙尼冰架和罗斯海冰架东部崩解和收缩趋势明显,东南极的冰架也有崩解和收缩,但没有西南极明显.陆架冰崩解向海洋输送的冰山对全球海平面升高有一定的影响.目前南极冰盖断裂崩解形成的冰山,向海洋输入的水量可使全球海平面上升约14mm.南极海冰没有随着全球气候温暖化而明显减少,而是按照东南极和西南极反相的变化规律进行周期性的变化、调整和制约.  相似文献   

20.
南海海温异常与ENSO的相关性   总被引:11,自引:0,他引:11  
使用1958-1987COADS资料,应用复经验正交函数(CEOF)分析方法,分析南海海表面温度场(SST)和风场(u及v)。结果发现,南海海温异常基本独立于西太平洋,同时存在类似于ENSO事件的年际变化,ENSO发生前冬季南海有异常降温过程,之后有增暖事件发生。分析还表明,南海SST异常主要取决于经向风场的异常强迫。南海SST与ENSO事件的相关性实质上反映了季风异常对ENSO循环的影响。  相似文献   

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