Phytoplankton spring and fall blooms in the North Atlantic in the 1980s and 2000s
Phytoplankton spring and fall blooms in the North Atlantic in the 1980s and 2000s
复制标题
DOI：
10.1029/2010jc006836
复制
发表时间：
2011-11-19
影响因子：
3.6
通讯作者：
Montegut, C. de Boyer
中科院分区：
文献类型：
--
作者：
Martinez, Elodie;Antoine, David;Montegut, C. de Boyer
浮游植物叶绿素a（Chl）的季节性周期的北大西洋使用卫星海洋颜色观测，涵盖1980年代和2000年代。研究区域是温暖的SST和更高的叶绿素在2000年代相比，20世纪80年代已报告。它覆盖了北纬30度至50度的纬度，从西经60度至西经0度的纬度，在那里发生了两次浮游植物水华：一次是在上层分层之后发生的春季水华，另一次是由于混合层加深而导致的营养物夹带而发生的秋季水华。在20世纪80年代，春季和秋季开花的幅度相似，在整个研究区域。在2000年代，秋季水华在大西洋东部（西经40度以东）较弱，因为在夏末混合层的加深延迟（混合层深度（MLD）从现场数据确定）。相反，东大西洋的春季开花在21世纪初比20世纪80年代更强，因为冬季的MLD更深，风更强。在西北大西洋（西北38度N-40度W），观察到春季和秋季开花以及冬季MLD的差异很小。我们的研究结果表明，上层分层，SST变化和生物反应之间的联系比简单的范例，依次涉及较高的分层与温暖的SST和增强（减弱）的增长的浮游植物种群在副极地（亚热带）地区更复杂。
Phytoplankton chlorophyll-a (Chl) seasonal cycles of the North Atlantic are described using satellite ocean color observations covering the 1980s and the 2000s. The study region is where warmer SST and higher Chl in the 2000s as compared to the 1980s have been reported. It covers latitudes from 30 degrees N-50 degrees N and longitudes from 60 degrees W-0 degrees W, where two phytoplankton blooms take place: a spring bloom that follows stratification of upper layers, and a fall bloom due to nutrient entrainment through deepening of the mixed layer. In the 1980s, spring and fall blooms were of similar amplitude over the entire study region. In the 2000s, the fall bloom was weaker in the eastern Atlantic (east of 40 degrees W), because of a delayed deepening of the mixed layer at the end of summer (mixed layer depth (MLD) determined from in situ data). Conversely, the spring bloom of the eastern Atlantic was stronger in the 2000s than it was in the 1980s, because of a deeper MLD and stronger winds in winter. In the Northwestern Atlantic (northwest of 38 degrees N-40 degrees W), little differences are observed for spring and fall blooms, and for the wintertime MLD. Our results show that the links between upper layer stratification, SST changes, and biological responses are more complex than the simple paradigm that sequentially relates higher stratification with warmer SST and an enhanced (weakened) growth of the phytoplankton population in the subpolar (subtropical) region.