“Flashes” of Chlorophyll-a Concentration Derived from in Situ and Remote Sensing Data at the Polar Front in the Barents Sea
“Flashes” of Chlorophyll-a Concentration Derived from in Situ and Remote Sensing Data at the Polar Front in the Barents Sea
复制标题
巴伦支海极锋现场和遥感数据中叶绿素a浓度的“闪光”
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
O. Pavlova
中科院分区：
文献类型：
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作者：
V. Kushnir;V. Pavlov;A. Morozov;O. Pavlova
巴伦支海的极锋区（PFZ）是北大西洋温暖的咸水（AtW）与寒冷的，密度较小的北极水（ArW）和融化的冰（MW）产生的淡水相互作用的区域。在春季，PFZ结构的大规模转变伴随着中尺度涡旋的发展，其特征尺寸为25至40公里。这种气旋漩涡中心的垂直速度可达20米/天，将营养物浓度高的深水输送到水面。海面的光合作用导致浮游植物大量生长，SeaWiFS和中分辨率成像分光仪的彩色扫描仪将其记录为叶绿素a浓度的急剧增加或“闪光”。对过去11年来这类闪电的统计分析表明，它们最有可能发生的时间是5月的最后一周。叶绿素a浓度的最大值呈Rayleigh分布，平均值为3.823 m / mg，标准差为1.983 m / mg。发生闪光的区域的特征尺寸对应于从内部Rossby变形半径的估计确定的中尺度涡旋的尺寸。由R/V“Lance”勘测观测到的这些涡流的位置与SeaWiFS光学扫描仪数据中看到的叶绿素a高浓度区相吻合。
The Polar Front Zone (PFZ) in the Barents Sea is an area where warm, salty water of the North Atlantic (AtW) interacts with cold, less dense, Arctic water (ArW) and the fresher water produced by melting ice (MW). In the spring a large-scale transformation of the structure of the PFZ is accompanied by the development of mesoscale eddies with characteristic sizes of 25 to 40 km. The vertical velocity in the centre of such cyclonic eddies can be up to 20 m/day, transporting deep water with high nutrient concentration up to the surface. Photosynthesis at the surface leads to intense phytoplankton development, which is registered by the color scanners of SeaWiFS and MODIS as a sharp increase, or "flash," in chlorophyll-a concentration. A statistical analysis of such flashes for the last 11 years has shown that the most probable time for their occurrence is the last week of May. Maxima of the chlorophyll-a concentration have a Rayleigh distribution with a mean of 3.82 3 m / mg and a standard deviation of 1.98 3 m / mg . The characteristic sizes of the areas where a flash occurs correspond to the size of mesoscale eddies determined from estimations of the internal Rossby deformation radius. The positions of these eddies, observed by the R/V "Lance" survey coincide with the zones of high chlorophyll-a concentration seen in the data from the optical scanner of SeaWiFS.