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The results of two airborne radiometer surveys of sea surface temperatures carried out east of New Zealand on 11 March and 28 April 1969 are presented, discussed in terms of the known oceanic circulation in the region, and compared with the pattern of sea surface temperature derived from a shipboard survey east of New Zealand, 1–14 March 1969. Short‐term temperature variations may be almost as large as the extreme annual range of sea surface temperatures.  相似文献   

3.
The spatio-temporal variabilities in sea surface temperature (SST) were analyzed using a time series of MODIS datasets for four separate regions in the Yellow Sea (YS) that were located along a north-south axis. The space variant temporal anomaly was further decomposed using an empirical orthogonal function (EOF) for estimating spatially distributed SST. The monthly SSTs showed similar temporal patterns in each region, which ranged from 2.4°C to 28.4°C in the study years 2011 to 2013, with seasonal cycles being stronger at the higher latitudes and weaker at the lower latitudes. Spatially, although there were no significant differences among the four regions (p < 0.05) in any year, the geographical distribution of SST was characterized by an obvious gradient whereby SST decreased along the north-south axis. The monthly thermal difference among regions was largest in winter since the SST in the southeast was mainly affected by the Yellow Sea Warm Currents. The EOF1 mode accounted for 56% of the total spatial variance and exhibited a warming signal during the study period. The EOF2 mode accounted for 8% of the total variance and indicated the warm current features in the YS. The EOF3 mode accounted for 6% of the total variance and indicated the topographical features. The methodology used in this study demonstrated the spatio-temporal variabilities in the YS.  相似文献   

4.
ASCAT洋面风资料在中国北方海域的真实性检验   总被引:2,自引:0,他引:2  
采用北方海域6个海洋观测站风资料对2009年3月—2013年6月ASCAT卫星反演洋面风(10 m)资料进行了检验。ASCAT反演洋面风与测站风向、风速偏差均较小,二者风速平均偏差为0.99 m/s,ASCAT风速略高于测站风速,二者风向平均偏差为-12.97°,表明ASCAT洋面风资料在北方海域具有可信性;分风级统计表明,在北方海域,风力为0—7级(0—17.1 m/s)时,利用ASCAT风速代表洋面风速是可行的(其中风力为4—5级时,ASCAT与测站风速误差最小,为0.10 m/s),当风力达到8级以上时ASCAT的可信度较低。  相似文献   

5.
Numerical experiments with the ECHAM5 atmospheric general circulation model have been performed in order to simulate the influence of changes in the ocean surface temperature (OST) and sea ice concentration (SIC) on climate characteristics in regions of Eurasia. The sensitivity of winter and summer climates to OST and SIC variations in 1998–2006 has been investigated and compared to those in 1968–1976. These two intervals correspond to the maximum and minimum of the Atlantic Long-Period Oscillation (ALO) index. Apart from the experiments on changes in the OST and SIC global fields, the experiments on OST anomalies only in the North Atlantic and SIC anomalies in the Arctic for the specified periods have been analyzed. It is established that temperature variations in Western Europe are explained by OST and SIC variations fairly well, whereas the warmings in Eastern Europe and Western Siberia, according to model experiments, are substantially (by a factor of 2–3) smaller than according to observational data. Winter changes in the temperature regime in continental regions are controlled mainly by atmospheric circulation anomalies. The model, on the whole, reproduces the empirical structure of changes in the winter field of surface pressure, in particular, the pressure decrease in the Caspian region; however, it substantially (approximately by three times) underestimates the range of changes. Summer temperature variations in the model are characterized by a higher statistical significance than winter ones. The analysis of the sensitivity of the climate in Western Europe to SIC variations alone in the Arctic is an important result of the experiments performed. It is established that the SIC decrease and a strong warming over the Barents Sea in the winter period leads to a cooling over vast regions of the northern part of Eurasia and increases the probability of anomalously cold January months by two times and more (for regions in Western Siberia). This effect is caused by the formation of the increased-pressure region with a center over the southern boundary of the Barents Sea during the SIC decrease and an anomalous advection of cold air masses from the northeast. This result indicates that, to estimate the ALO actions (as well as other long-scale climatic variability modes) on the climate of Eurasia, it is basically important to take into account (or correctly reproduce) Arctic sea ice changes in experiments with climatic models.  相似文献   

6.
The leading modes of interannual and long-term variations in the stratospheric and tropospheric circulation and total ozone (TOMS data) and their relations to Northern Hemisphere sea surface temperature (SST) anomalies are investigated using the monthly mean NCEP/NCAR reanalysis data for the winter months of 1958–2003. Strong correlations are indicated between the interannual total ozone variations over Labrador and the North Atlantic and changes in the stratospheric polar vortex. The onset of major stratospheric warmings is connected not only with the strengthening of westerlies at the 500-hPa level in the midlatitude Atlantic, but also with the weakening of tropospheric winds over the north of eastern Siberia and strengthening over the Far East. In years with major stratospheric warmings, abnormally cold winters are observed in Eurasia, especially in eastern Siberia and northeastern China. The calculated simultaneous (with no time lags) correlations of the stratospheric circulation changes with El Niño/La Niña events give evidence of low correlations between the tropical Pacific SST anomalies and the stratospheric dynamics in the Arctic. However, there are high correlations of the extratropical Pacific and Atlantic SST anomalies with interannual tropospheric and stratospheric circulation variations, the stratospheric dynamics being more strongly connected with Pacific SST than with Atlantic SST anomalies. The interannual changes in tropospheric circulation are coupled to SST anomalies in both the Pacific and the Atlantic. Mechanisms of long-term changes in the interactive ocean-atmosphere-ozone layer system are discussed.  相似文献   

7.
本研究分别于2019年7月(夏季)和12月(冬季)对澄迈马袅湾网箱养殖区及周边海域的大型底栖生物进行调查。结果表明,两次调查共采集鉴定到55种生物,其中夏季31种,主要分布在邻近区;冬季33种,主要分布在养殖区和邻近区。夏季航次,底栖生物在养殖区、邻近区和对照区的栖息密度分别为30.55 ind/m2、40.74 ind/m2和29.63 ind/m2,生物量分别为14.36 g/m2、6.28 g/m2、6.58 g/m2;冬季航次,三个海区底栖生物栖息密度分别为55.56 ind/m2、46.67 ind/m2和27.78 ind/m2,生物量分别为7.29 g/m2、6.20 g/m2和0.22 g/m2。夏季优势种主要为绒毛细足瓷蟹和纽虫;冬季优势种主要为豆形短眼蟹、梳鳃虫、纽虫和哈氏美人虾。夏季养殖区、邻近区和对照区大型底栖生物多样性指数(H′)分别为1.40、2.06和1.46;冬季分别为2.16、1.59和0.94。综上分析,网箱养殖产生的残饵和鱼类粪便,对养殖区及邻近海域底栖生物分布产生一定影响,且其群落结构与区域和季节存在较强相关性。  相似文献   

8.
The effects of hypoxic bottom water, an annual event, were documented on the inner shelf off Cameron, Louisiana during the summer of 1981. Populations of most species of macrobenthos were dramatically reduced. In an area of fine sediment that was numerically dominated by polychaetous annelids, the most severely affected populations were those of tube-dwelling and surface-feeding species. Burrowing species were less influenced by the hypoxia.  相似文献   

9.
Seasonal variations of macrobenthos communities were analyzed over six years at two fixed stations at the depths of 500 m and 1,000 m in the bathyal zone off Sanriku, northeastern Japan, and were compared with those of the 80 m station established at the mouth of Otsuchi Bay, northeastern Japan. Significant seasonal variations of macrobenthos density were detected at the 80 m and 500 m stations. While the density increased in late spring and decreased until July at the 80 m station, it increased between May and August, and decreased in September at the 500 m station. At the 1,000 m station, no seasonal variation of macrobenthos abundance could be detected. The seasonal variations of the density observed at the 80 m and 500 m stations are probably related to that of the supply of organic materials derived from surface phytoplankton. Differences in the patterns of seasonal variations among the three stations may reflect the different periods of food supply to the sea floor. Significant seasonal variation in the feeding structure of the polychaete communities could be detected at the 80 m and 1,000 m stations.  相似文献   

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11.
连续台风对海表温度和海表高度的影响   总被引:1,自引:0,他引:1  
利用多卫星观测资料,分析了2008年9月3个连续台风前后的海表温度(SST)和海表高度距平(SSHA)的时空变化特征,并探讨了影响其变化的主要因子。结果表明:(1)3个台风引起了强烈的上升流(1×10-5~150×10-5 m/s),海表显著降温(1~6 ℃),海表高度也有不同程度降低(10~50 cm);(2)台风引起的SST最大降温中心与SSHA负值或中尺度冷涡的区域中心十分吻合,同时台风使得先前存在的海洋中尺度冷涡得到加强;(3)同一区域台风对SST影响程度大小受台风的强度、移动速度以及台风对海面强迫时间等因素控制;(4)在原先SSHA为正值的海域,3个台风连续强迫下使得局地洋面形成一个SSHA为负值的中尺度涡,这与单一"打转"台风强迫海洋生成中尺度涡的现象不同。因此,对于西北太平洋海域而言,频发的台风在中尺度涡生消演变过程中的影响应不容忽视。  相似文献   

12.
为研究东部型和中部型两类厄尔尼诺(El Ni?o)事件与中国近海海表温度(sea surface temperature,SST)变化间的联系,基于中国科学院大气物理研究所连续80年(1940—2019年)的SST再分析数据,采用EOF分解、合成分析等方法做了初步分析,发现中国近海及毗邻海域近80年SST变化与全球变暖密切相关。并且两类El Ni?o事件对中国近海SST变化的影响存在显著差异。东部型El Ni?o事件发展过程中,中国近海及毗邻海域SST在发展年主要为负异常,衰退期为正异常;中部型ElNi?o事件发展过程中, SST变化区域差异大,发展年日本附近海域为正异常, 28°N以南为弱的负异常。两类El Ni?o事件引发西太平洋风场反气旋涡的时间、位置与强度等的不同,是造成中国近海风场与海表温度异常(sea surface temperature anomaly, SSTA)差异的主要原因。  相似文献   

13.
An accurate platinum resistance thermometer (PRT) has been installed on a commercial ferry that operates between Hillarys Marina, some 15 km north of Fremantle, and Rottnest Island off the Western Australian coast. The PRT is located in the engine intake system and provides continuous under-way measurements of the bulk sea surface temperature (SST) at a depth of 1 m. The “SeaFlyte” ferry makes the trip to Rottnest Island between 3 and 5 times daily and so a wealth of data is available for comparison with the SST derived using data from the GLI instrument on ADEOS-II. Analyses of the ferry and satellite data confirm the excellent quality of SST estimates from the GLI as well as four other satellite instruments—AVHRR on NOAA-16, AATSR on ENVISAT, and the MODIS instruments on TERRA and AQUA. All satellite instruments showed a comparison standard deviation of better than 0.6°C with GLI being better than 0.4°C. The number of ferry-satellite data coincidences used in this study demonstrates one of the advantages of installing measurement systems on commercial ships that operate regular passenger or freight services rather than infrequent deployments on research vessels. The analyses also demonstrate that satellite-derived SST estimates obtained under low surface wind conditions must be treated with care.  相似文献   

14.
The macrozoobenthos living around two offshore gas platforms, Barbara NW (pB) and Calipso (pC) located in the northwestern Adriatic Sea were investigated for three years after their construction to detect eventual effects due to the platforms. The sampling stations were spaced at increasing distance from the platforms up to 1000 m. Both multivariate and univariate analysis showed an initial defaunation (short-term effect) at pB and within a 120 m radius at pC. A general recovery in terms of abundance, species richness and diversity was observed for the benthic communities after one year. During the third monitoring year a mussel mound developed at both the platforms (longer-term effect) extending up to 30 m from pC, whereas similar soft-bottom communities were found at all the other distances. The geographical position plays an important role in the “timing” of the above effects. Moreover, despite the different environmental features, a 3-year monitoring plan can be effective to evaluate the potential impact on benthic communities of offshore gas platforms in the north-central Adriatic Sea.  相似文献   

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利用WRF(Weather Research and Forecasting)模式,针对1次陆雾与1次同时包含近海雾区与开阔海域雾区的海雾个例,开展了2种陆面方案——SLAB(five-layer thermal diffusion scheme)方案与Noah(Noah land surface scheme)方案—...  相似文献   

17.
利用来自ECMWF的ERA-40风场资料,就北印度洋海表风速的长期变化趋势展开分析,以期可为海洋水文保障、防灾减灾、研究全球气候变化提供参考.结果表明:(1)1958-2001年期间,北印度洋低纬度海域、索马里至斯里兰卡一带的大范围海域的海表风速表现出显著的逐年线性递增趋势,基本在0.01-0.02 m·s-1·a-1;呈显著性递减的区域主要分布于亚丁湾、红海、波斯湾、斯里兰卡北部零星海域、以及缅甸仰光西南部近海等小范围海域,约-0.01-0.005m·s-1·a-1;阿拉伯海、孟加拉湾等海域的海表风速在近44年期间则无显著性变化趋势;(2)近44年期间,北印度洋海域的海表风速整体上以0.0061m·s-1 ·a-1的速度显著性震荡递增,震荡区间在5.0-5.5 m·S-1之间;(3)不同海域海表风速的变化趋势在不同季节表现出很大差异:冬季和夏季,大部分海域海表风速的变化趋势显著,春季次之,秋季仅在赤道附近一带海域呈显著性递增;(4)近44年期间,北印度洋的海表风速存在显著的2.0年、2.6-3.7年、5.2年的变化周期,以及26年以上的长周期震荡.  相似文献   

18.
Quantitative samples of sediments and macrobenthos were collected with a spade corer to reveal the relationships between macrobenthos communities and bottom environments. Twenty-five stations were established along a transect in the lower sublittoral and bathyal zones between the depths of 120 m and 2,600 m off Sanriku, the northeastern coast of the Japanese mainland, Northwestern Pacific.These stations were clustered into two groups on the basis of the principal component analysis of environmental factors and topographic features of the study area. The clustering of stations corresponded to that based on polychaete species composition.The biomass of macrobenthos followed two different patterns in two oceanographic environments; the first trend is found from the shelf to the seaward margin of the deep-sea terrace where macrobenthos biomass did not depend on depth, and the second trend on the lower continental slope, where biomass decreased exponentially with depth as Rowe's formula predicted. The density of macrobenthos showed a simple exponential decrease with depth over the two ecological zones. The data of stable carbon isotope ratio of organic matter in the sediments and topographic features suggested that the pattern of the biomass of macrobenthos corresponded with two different modes of food supply to the deep-sea bottom communities,i.e., vertical transport of the surface products and horizontal transport of food materials.  相似文献   

19.
Records of four species of Delphinidae, Delphinus delphis, Lissodelphis peroni, Lagenorhynchus obscurus, and Lagenorhynchus cruciger in waters to the east and south‐east of New Zealand are discussed in relation to surface temperatures.

In this region D. delphis appears to be largely confined north of the Subtropical Convergence and a minimum surface temperature of about 14°c, and near New Zealand from Hawke Bay southward in the warm water of the East Cape Current; L. peroni to the Subtropical Convergence and the subantarctic water to the south of it, between surface temperatures of 9°c and 16°c; L. obscurus to the immediate vicinity of the Subtropical Convergence and surface temperatures in summer of about 14° to 15°c, and L. cruciger across the Antarctic Convergence region, in a surface temperature range of 2° to 9°c.  相似文献   

20.
Ocean temperatures are rising throughout the world, making it necessary to evaluate the impact of these temperature changes on sea urchins, which are well-known bioindicators. This study evaluated the effect of an increase in temperature on the immune response of the subtidal Lytechinus variegatus and the intertidal Echinometra lucunter sea urchins. Both species were exposed to 20 (control), 25 and 30 °C temperatures for 24 h, 2, 7 and 14 days. Counting of coelomocytes and assays on the phagocytic response, adhesion and spreading of coelomocytes were performed. Red and colorless sphere cells were considered biomarkers for heat stress. Moreover, a significant decrease in the phagocytic indices and a decrease in both cell adhesion and cell spreading were observed at 25 and 30 °C for L. variegatus. For E. lucunter, the only alteration observed was for the cell proportions. This report shows how different species of sea urchins respond immunologically to rising temperatures.  相似文献   

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