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1.
海表温度(sea surface temperature,SST)是影响全球气候的重要因素,在海洋科学研究中占有关键位置。论文基于MODIS红外、AMSR-2和HY-2A微波辐射计数据,分别利用最优插值和贝叶斯最大熵方法对SST数据进行融合,并用i Quam实测数据和Argo浮标数据对2015年SST融合数据进行检验。MODIS、AMSR-2、HY-2A辐射计SST的年平均空间覆盖率分别为15.0%,21.6%,22.0%,最优插值和贝叶斯最大熵融合SST产品的年平均空间覆盖率提高到98.6%和99.4%,融合产品空间覆盖率明显提高。与i Quam实测数据对比,最优插值和贝叶斯最大熵融合产品年平均偏差分别为0.07℃,0.04℃,均方根误差皆为0.78℃,其中3-7月最优插值融合产品的精度略优于贝叶斯最大熵融合产品,其它月份则相反;与Argo浮标数据对比,两种融合产品的均值偏差分别为0.06℃,0.01℃,均方根误差分别为0.77℃,0.75℃。整体上,贝叶斯最大熵融合产品的精度略优于最优插值融合产品,但计算成本较高。 相似文献
2.
南海北部海域叶绿素a浓度时空特征遥感分析 总被引：4，自引：1，他引：3
利用2007-2010年MODIS的L2级叶绿素a浓度产品作为数据基础, 对叶绿素a浓度年平均和月平均数据进行分级分区处理, 研究南海北部海域叶绿素a浓度时空分布特征及其与海洋环境因素的关系。初步研究结果表明:2007-2010年在南海北部海域叶绿素a浓度的高值区(>5.0 mg/m3)主要分布在广东省沿岸河流的入海口, 分布范围在夏季最大, 在春秋次之, 在冬季最小;叶绿素a浓度的次高值区(1.0～5.0 mg/m3)主要分布在海岸线到50 m等深线之间的海域, 分布范围夏冬较大, 能扩展到50 m等深线附近, 而春秋较小, 会退缩到50 m等深线以内;叶绿素a浓度的中值区(0.3～1.0 mg/m3)主要分布在50 m到100 m等深线之间的海域, 时空变化复杂;叶绿素a浓度的低值区(<0.3 mg/m3)主要分布在100 m等深线以外的海域, 其区域平均值夏季最低, 春秋次之, 冬季最高, 同时该区域叶绿素a浓度在春夏秋三季空间分布较均匀, 而冬季受季风和黑潮入侵影响空间分布较为复杂。南海北部海域海表叶绿素a浓度的时空变化特征与季风、沿岸河流、海流、海表温度等海洋环境因素的变化有关。 相似文献
3.
西北太平洋红外辐射计海表温度数据交叉比对分析 总被引：6，自引：2，他引：4
本文将西北太平洋海域作为研究区域,以2003—2009年的三个海表温度(sea surface temperature,SST)红外产品(AVHRR Pathfinder/NOAA,MODIS/Terra和MODIS/Aqua)为研究对象,分别与Argo浮标数据进行了真实性检验,同时红外产品之间也进行了交叉比对分析。通过评定产品间的差异及使用条件,为融合产品数据源选取和权重分配提供参考依据,用以提高融合产品的数据质量。结果表明,三种红外数据与Argo浮标的平均偏差在±0.2°C之间,均方根误差小于0.8°C,且存在明显的季节性变化,白天的平均偏差均是夏季为正、冬季为负,夜间的平均偏差基本均为负偏差,冬季比夏季的偏差更大,冬季的均方根误差较小;三种红外数据之间的平均偏差在±0.1°C之间,均方根误差小于0.6°C;三个红外产品在空间上均能反映西北太平洋海域的海表温度变化趋势,三个产品之间无明显优劣差异;尽管红外数据的空间覆盖率偏低,但是它提供了高精度和高特征分辨率的数据产品,并弥补了近岸海域缺乏观测数据的不足。 相似文献
4.
SeaWiFS和MODIS叶绿素浓度数据及其融合数据的全球可利用率 总被引：2，自引：0，他引：2
对2001年Sea WiFS和MODIS叶绿素浓度数据的全球可利用率进行了定量分析，二者在全球范围的变化趋势一致，年平均可利用率分别为12．4％和13．6％，其中MODIS叶绿素浓度的可利用率略高于SeaWiFS。利用小波变换方法对二者进行数据融合，经分析：SeaWiFS／MODIS叶绿素浓度融合数据相对于单一传感器数据提高了全球可利用率，其年平均为20．50％；融合数据保持了较高空间分辨率MODIS数据的海洋特征；融合数据与实测值比较，差值的均值和标准偏差分别为0．16mg／m^3和1．07mg／m0（SeaWiFS：0．46mg／m^3和2．22mg／m^3，MODIS：0．13mg／m^3和0．82mg／m^3）。与MODIS和Sea WiFS相比。融合数据接近MODIS优于SeaWiFS。结果表明小波变换方法用于SeaWiFS和MODIS叶绿素浓度数据融合的有效性。 相似文献
5.
北太平洋鱿鱼渔场叶绿素a分布特点及其与渔场的关系 总被引：11，自引：3，他引：8
根据2001年～8月对位于39°～43°N,152°E～171°W的北太平洋鱿鱼渔场进行的水温、盐度、叶绿素a、浮游植物和鱿鱼捕捞等的调查结果,主要分析北太平洋鱿鱼渔场表层叶绿素a分布特点及其与环境因子、中心渔场的关系.分析结果表明,调查区表层叶绿素a含量变化为0.03～0.32 mg/m3,平均为0.13 mg/m3,其中中部渔场表层叶绿素a含量值最大,东部渔场次之,西部渔场最低;调查海域表层叶绿素a含量分布与表层温度、盐度存在较好的对应关系,叶绿素a含量高值区对应高温区,冷涡区含量最低,暖涡区含量最高;叶绿素a含量随盐度的增加而增加;在西部、中部、东部渔场,表层叶绿素a含量与浮游植物数量呈正相关关系;表层叶绿素a的分布与鱿鱼中心渔场存在较好的对应关系,中心渔场主要位于0.1 mg/m3叶绿素a等值线舌状部分或叶绿素a水平梯度较大处,渔场中心的叶绿素a值大于0.1 mg/m3.叶绿素a分布与环境要素及渔场的相关性分析表明叶绿素a可作为鱿鱼渔场分析中的一个重要参考指标. 相似文献
6.
北部湾浮游植物粒径分级叶绿素a和初级生产力的分布特征 总被引：19，自引：4，他引：19
1994年5月23B至6月4日现场观测了北部湾浮游植物细胞丰度、叶绿素a浓度和初级生产力的分布.测区平均叶绿素a浓度为0.94±0.45/d3.平均初级生产力(C)为351±172mg/(m2·d),浮游植物细胞丰度为0.97×104-10050×104个/m3,鉴定浮游植物4门56属176种.地理环境和水文状况的差异使上述参数分布具有明显的区域性特征,近岸区高于湾中部,测区北部高干南部;温跃层以下水层叶绿素a浓度高于上层水,周6观测站平均叶绿素a浓度湾北部(0.47±0.15g/dm3)高于湾南部(0.15±0.02dm3).北部湾水域光合浮游生物以微型和微微型细胞(小于20m)占优势,其对总初级生产力的贡献(占91%)高于对总叶绿素a的贡献(占77%). 相似文献
7.
《海洋技术学报》2015,(6)
利用2002-2013年MODIS/Aqua的Level 1B数据,经标准大气校正算法和叶绿素a浓度[chl-a]波段比经验算法(OC2M-HI),获得近12 a的胶州湾及青岛近海海域晴空的MOIDS/Aqua叶绿素a浓度。根据GOCI/COMS和MODIS/Aqua叶绿素a浓度产品在胶州湾及青岛近海交叉比较的结果[1],对2002-2013年的MODIS/Aqua[chl-a]进行了修正。基于修正后的MODIS/Aqua[chl-a]分析了胶州湾及青岛近海的叶绿素a浓度年变化特征。该海域的叶绿素a浓度大致呈现北高南低,湾内高于近海的特点,且每年空间分布趋势基本一致;近12 a的[chl-a]呈小的上升趋势,胶州湾的上升趋势大于青岛近海。胶州湾跨海大桥建设前,其附近区域叶绿素a浓度以0.47μg/L/year的趋势上升,基值为2.62μg/L;大桥开建及通车后,其附近叶绿素a浓度年变化趋势不明显,但基值明显增大(4.00μg/L)。 相似文献
8.
三门湾秋季浮游植物现存量和初级生产力 总被引：3，自引：0，他引：3
对1987年9月浙江三门湾海区浮游植物细胞丰度、叶绿素a浓度和初级生产力的分布特征及其与环境的关系进行了研究。结果表明,调查海区的浮游植物细胞丰度、叶绿素a浓度和初级生产力均具有明显的空间区域性分布特征。叶绿素a浓度高值区位于三门湾顶部和健跳港口,从湾顶部往湾口海区方向,叶绿素a浓度逐渐下降。初级生产力的分布趋势与叶绿素a浓度的分布趋势一致。表层水浮游植物平均细胞丰度为(3.36±1.39)×103个/dm3,表、底层平均叶绿素a浓度分别为(1.47±0.42)μg/dm3和(1.12±0.19)μg/dm3,平均初级生产力为(36.0±29.5)mg/(m2·d)。 相似文献
9.
为提高降雨条件下星载全极化微波辐射计海面风场精度,通过匹配WindSat海面风场和降雨率数据以及美国国家浮标中心浮标观测数据,得到18 996组匹配样本,深入分析了降雨对海面风场反演精度的严重影响,构建了风场校正模型。试验结果表明,降雨导致海面风速被严重高估,风向误差随着降雨率的增大而增大。校正后的风速精度在低风速段提升明显。无论降雨率多大,校正后风速精度均比校正前高。风速均方根误差由原来的2.9 m/s降低到了2.1 m/s,风向均方根误差由原来的26.9°降低到了26.3°。 相似文献
10.
中分辨率成像光谱仪(CMODIS)是我国“神舟3号”飞船上对地观测主载荷,是我国第一台上天的具有测量海面叶绿素a浓度能力的成像光谱仪.利用宽视场海洋水色扫描仪(SeaWiFS)反演叶绿素a浓度作为参考值建立CMODIS资料处理模型,得到三个基于蓝绿波段比值法的叶绿素a浓度反演算法,平均相对误差分别为26.6%,24%和33.5%,均方根误差分别为1.16,1.15和1.23 mg/m3.在叶绿素a浓度反演误差允许范围小于35%的条件下,比值算法的适用范围为悬浮泥沙浓度小于5 g/m3的海区.悬浮泥沙的强散射作用导致比值算法在高悬浮泥沙浓度条件下产生高估叶绿素a浓度反演值的现象;在中低悬浮泥沙浓度的海区,悬浮泥沙和浮游植物对离水辐亮度的综合作用使比值算法存在低估叶绿素a浓度的趋势. 相似文献
11.
认识海洋在全球碳循环中的作用及其对环境变化的响应，需要高时空分辨率的观测数据。由于轨道宽度、云雨天气、太阳耀斑等的影响，单一的水色传感器的观测能力十分有限，将多源海洋水色卫星进行融合是提高水色数据时空覆盖的一种有效途径。SeaWiFS和MERIS分别于2010年12月11日和2012年5月9日停止运行，在很大程度上降低了水色融合产品时空覆盖的提升。我们在融合过程中加入了FY-3 MERSI数据，生成了全球海洋叶绿素浓度遥感融合产品数据集。数据源包括SeaWiFS、MERIS、MODIS-Aqua、VIIRS和MERSI。结果表明：加入MERSI后，融合产品的日平均有效空间覆盖提高了9%；采样频率（同一区域一年中获取有效数据的次数）由57天/年提高到109天/年。利用实测数据和国外同类融合产品（ESA GlobColour和NASA MEaSUREs）对新的数据集进行了质量评价。与实测数据相比，加入MERSI的融合产品精度与未加入MERSI的融合产品基本一致；与国外同类融合产品的偏差小于10%。新数据集的时间序列特性与未加入MERSI的融合产品以及单传感器的一致。 相似文献
12.
Sei-Ichi Saitoh Denzo Inagake Kousei Sasaoka Joji Ishizaka Yukihiro Nakame Toshiro Saino 《Journal of Oceanography》1998,54(5):495-508
Synoptic ship and satellite observations were performed of the Kuroshio warm-core ring (KWCR) 93A and its adjacent waters,
off Sanriku, northwestern North Pacific, between early April and late June 1997. The temporal and spatial distribution of
chlorophylla (Chl-a) and sea surface temperature in the study area were analyzed using data from ADEOS Ocean Color and Temperature Scanner (OCTS)
and NOAA Advanced Very High Resolution Radiometer (AVHRR). The objective of this study was to describe the temporal and spatial
variability of the spring bloom and understand its relationship with the changes in the hydrographic structure of these waters
in and around KWCR 93A. The maximum value of Chl-a concentration in the ring was less than 1 mg/m3 during April. The spring bloom in the ring occurred early in May and the relatively high maximum (>1.0 mg/m3) continued from early in May to mid-June. In late June, a ship-observed surface Chl-a concentration of less than 0.4 mg/m3 suggests that the spring bloom had already declined in and around KWCR 93A. Double spiral structures of warm and cold streamers
appeared from late April to mid-May, which may have an influence on the occurrence of the spring bloom in and around the ring.
In this episodic event, the warm streamer can maintain the available potential energy of the ring and the strength of upwelling
around the ring. The cold streamer provided water with a high Chl-a concentration to the surface layer of the ring. In order to understand the temporal and spatial variability of Chl-a distribution in the ring, the behavior of the warm and cold streamers needs to be taken into consideration. 相似文献
13.
Chlorophyll-a (chl-a) concentration has an important economic effect in coastal and marine environments on fisheries resources and marine aquaculture development. Monthly climatologies the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) derived chl-a from February 1998 to August 2004 around Funka Bay were used to investigate the spatial and temporal variability of chl-a concentrations. SeaWiFS-derived suspended sediment, MODIS derived sea surface temperature (SST), solar radiation and wind data were also analyzed. Results showed two distinct chlorophyll blooms in spring and autumn. Chl-a concentrations were relatively low (<0.3 mg m−3) in the bay during summer, with high concentrations occurring along the coast, particularly near Yakumo and Shiraoi. In spring, chl-a concentrations increased, and a large (>2 mg m−3) phytoplankton bloom occurred. The spatial and temporal patterns were further confirmed by empirical orthogonal function (EOF) analysis. About 83.94% of the variability could be explained by the first three modes. The first chl-a mode (77.93% of the total variance) explained the general seasonal cycle and quantified interannual variability in the bay. The spring condition was explained by the second mode (3.89% of the total variance), while the third mode (2.12% of the total variance) was associated with autumn condition. Local forcing such as the timing of intrusion of Oyashio water, wind condition and surface heating are the mechanisms that controlled the spatial and temporal variations of chlorophyll concentrations. Moreover, the variation of chlorophyll concentration along the coast seemed to be influenced by suspended sediment caused by resuspension or river discharge. 相似文献
14.
Ocean Color Satellite Imagery and Shipboard Measurements of Chlorophyll a and Suspended Particulate Matter Distribution in the East China Sea 总被引：1，自引：0，他引：1
Satellite-derived ocean color data of Coastal Zone Color Scanner (CZCS) on board the Nimbus-7 and Ocean Color and Temperature Scanner (OCTS) on board the Advanced Earth Observing Satellite (ADEOS) are jointly used with historical in situ data to examine seasonal and spatial distributions of chlorophyll a (Chl-a) and suspended particulate matter (SPM) concentrations in the East China Sea. Ocean color imagery showed that Chl-a concentrations on the continental shelf were higher than those of the Kuroshio area throughout the year. Satellite-derived Chl-a concentrations are generally in good accordance with historical in situ values during spring through autumn (although no shipboard in situ measurement was conducted at nearshore areas). In contrast, ocean color imagery in winter indicated high Chl-a concentrations (4–10 mg m–3) on the continental shelf where bottom depth was less than 50 m when surface water was turbid (2–72 g m–3 of SPM at surface), while historical in situ values were usually less than 1 mg m–3. This suggests that resuspended bottom sediment due to wind-driven mixing and winter cooling is responsible for the noticeable overestimation of satellite-derived Chl-a concentrations. The algorithm for ocean color needs to be improved urgently for turbid water. 相似文献
15.
南海北部表层颗粒有机碳的季节和年际变化遥感分析 总被引：1，自引：1，他引：0
海洋颗粒有机碳（POC）是海洋固碳的一个关键参数。为了研究南海北部陆架及海盆表层POC浓度的时空分布特征以及变化趋势,本文利用2009-2011年4个季节的实测数据,对NASA发布的MODIS/AQUA卫星月平均POC遥感产品,进行了验证和校正;并利用校正后的遥感数据分析了2003-2014年POC的时空分布特征和变化趋势。发现POC遥感产品与南海北部实测数据具有较好的线性关系（R2=0.72）,但存在系统性偏高,需利用实测数据对遥感数据进行区域性校正。分析校正后的遥感数据发现,南海北部陆架POC浓度较高,平均为（33.34±8.02）mg/m3;吕宋海峡西南海域浓度较低,平均为（29.25±6.20）mg/m3;中央海盆区浓度最低,平均为（27.02±4.84）mg/m3。春夏季POC浓度较低,最低值一般出现在5月,冬季（12月至翌年1月）POC浓度达到最高。利用2003-2014年的长时间序列遥感叶绿素（Chl a）和海表温度（SST）、混合层深度（MLD）模式数据,以及实测数据对南海北部POC浓度的影响机制进行了分析。发现POC与Chl a在秋冬呈现较好的相关关系（R2=0.51）,但在春夏季较离散,表明秋冬季生物作用对POC影响较大。2003-2014年期间,POC与Chl a、MLD及SST存在明显的年际变化,但并没有显著的上升或下降趋势。 相似文献
16.
In December–January of 2010 the spatial distribution of the phytoplankton production characteristics was studied along transects
in the vicinity of the Greenwich meridian (I) and in the Drake Passage (II). On transect I, the surface chlorophyll a concentration and primary production varied from 0.11 up to 3.57 mg/m3 and from 4.38 up to 37.47 mgC/m3 per day, respectively. The chlorophyll a in the photosynthetic layer and the integrated primary production varied from 10.7 up to 66.1 mg/m2 and from 83 to 646 mgC/m2 per day, respectively. On transect II in the surface layer, the chlorophyll a concentration changed within the range of 0.09–1.02 mg/m3 and the primary production ranged from 2.08 to 9.49 mgC/m3. The integrated values ranged from 6.32 to 38.29 mg/m2 and from 41 to 221 mgC/m2 per day, respectively. The moderate means of themaximum quantum yield (F
v/F
m) on transects I and II (0.41 and 0.35, respectively) testify to the low activity of the phytoplankton’s photosynthetic apparatus.
The studied water areas in the Southern Ocean differed both in the phytoplankton biomass expressed in the chlorophyll a concentration values and in the conditions of the primary production formation. 相似文献
17.
18.
The time series of multiple sources of satellite data are used to examine the interannual variability of chlorophyll a concentration （Chl a） and its relation to the physical environment during the autumn monsoon transitional period in the Taiwan Strait （TWS）. The satellite data included the Chl a concentration and sea surface temperature （SST） derived from the Moderate Resolution Imaging Spectroradiometer （MODIS）/ Aqua as well as the multi-sensors merged wind products from 2002 to 2012. The results show that the average Chl a concentration of the whole TWS is mainly contributed by the northern TWS. The average Chl a in the northern TWS is 3.6 times that in the southern TWS. The maximum variability of Chl a is located in the frontal regions between the cold Zhe-Min Coastal Water and the strait warm water. The temporal change of Chl a concentration is different in the northern and southern TWS. The changes in the relative strength of the cold and warm water masses is suggested to be the dominant processes in controlling the phytoplankton growth in the northern TWS, while there is wind-induced mixing in the southern TWS. Additionally, La Nina events exhibited complex effects on the interannual variability of Chl a concentration in autumn. The longterm time series of physical and biological observations are especially needed to better understand how the TWS complex ecosystem responds to climate variations. 相似文献
19.
An analysis is presented of data on chlorophyll a concentrations of the total and the netplankton (>10 μm), determined either in April to June or in August to September from
48°N to 15°S along 175°E in the Pacific Ocean during 6 years by the NOPACCS (Northwest Pacific Carbon Cycle Study). Particular
attention was given to the variability of absolute concentrations of the netplankton chlorophyll a and their percentage shares of the total chlorophyll a concentration. Below 0.2 μg l−1 of surface total chlorophyll a, the netplankton chlorophyll a showed low percentage shares (such as 12.7% on average) with a large variation, but above 0.2 μg l−1 it was 35.9% on average with less variation, showing an accelerated increase at high total chlorophyll a concentrations. High netplankton chlorophyll a concentrations in surface waters were observed at high latitudes, in waters having high chlorophyll a concentrations at sub-surface depth, and in equatorial upwelling. The percentage shares of netplankton in the total chlorophyll
a in the euphotic zone were 8.5% and 25.9% above and below 0.2 μg l−1, respectively, although the data points scattered over a wide range (from 7.2% to 53.8%) depending on differences in water
masses, depths and seasons. High chlorophyll a concentrations and high percentage shares of netplankton corresponded to high ambient nitrate plus nitrite concentrations.
Integrated netplankton chlorophyll a concentrations in the euphotic zone varied from 0.7 to 19.5 mg m−2 in waters below 0.2 μg l−1 of surface total chlorophyll a, and from 2.0 to 29.5 mg m−2 above 0.2 μg l−1, and the percentage shares of netplankton for the former were 7.4% on average and 23.7% for the latter.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
根据2011年6月茅尾海生态环境调查资料,对该海域海水和表层沉积物中叶绿素a的空间分布进行了分析。结果表明,海水叶绿素a变化范围1.384~4.060 mg/m3,平均值为2.143 mg/m3,表层沉积物叶绿素a范围为0.006~0.740 mg/kg(湿重),均值为0.124 mg/kg;海水与表层沉积物叶绿素a均呈现自河口向南逐渐降低的空间分布特征。单位面积表层沉积物叶绿素a平均含量为上方水柱叶绿素a平均含量的129.44%,沉积物对该海域初级生产力有显著的潜在贡献。相关分析表明,海水和沉积物叶绿素a均与无机氮及底栖动物栖息密度呈显著或极显著的正相关关系(P0.05或P0.01)。 相似文献