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11.
本文对8个活动区极性反转线(中性线)附近黑子半影纤维的形态进行了分析得出:1)具有强δ磁结构的活动区,穿过主要异极性黑子间的中性线近旁半影纤维或多或少地与中性线平行(交角小于30°),有关黑子半影呈旋涡形态;2)由新浮现发展形成的δ结构区,异级黑子在大黑子边缘或与大.黑子本影之间有一段距离,中性线两边的半影纤维有序排列,走向与中性线斜交,有关黑子呈弱的旋涡形态。3)对于较稳定的极群,N、S极性间的宽窄不一的半影稀疏区,中性线沿该区经过,两旁半影松散齿状,走向与中性线大体垂直,相反极性本影间距较远。 相似文献
12.
Concentrations and flux densities of methane were determined during a Lagrangian study of an advective filament in the permanent upwelling region off western Mauritania. Newly upwelled waters were dominated by the presence of North Atlantic Central Water and surface CH4 concentrations of 2.2 ± 0.3 nmol L−1 were largely in equilibrium with atmospheric values, with surface saturations of 101.7 ± 14%. As the upwelling filament aged and was advected offshore, CH4 enriched South Atlantic Central Water from intermediate depths of 100–350 m was entrained into the surface mixed layer of the filament following intense mixing associated with the shelf break. Surface saturations increased to 198.9 ± 15% and flux densities increased from a mean value over the shelf of 2.0 ± 1.1 μmol m−2 d−1 to a maximum of 22.6 μmol m−2 d−1. Annual CH4 emissions for this persistent filament were estimated at 0.77 ± 0.64 Gg which equates to a maximum of 0.35% of the global oceanic budget. This raises the known outgassing intensity of this area and highlights the importance of advecting filaments from upwelling waters as efficient vehicles for air-sea exchange. 相似文献