在热带海洋中扩大氧气最小区
Lothar Stramma1, Gregory C Johnson, Janet Sprintall
1Institut für Meereswissenschaften an der Universität Kiel (IFM-GEOMAR), Düsternbrooker Weg 20, 24105 Kiel, Germany. lstramma@ifm-geomar.de
概括
海洋氧气水平正在下降,热带海洋的缺氧区域正在扩大. 这种扩张威胁到海洋生态系统和沿海经济,因为溶解氧的减少.
科学领域:
- 海洋学 海洋学 海洋学
- 海洋生物学 海洋生物学
- 气候科学 气候科学
背景情况:
- 缺乏氧气的水域在中等深度的热带海洋中普遍存在.
- 低毒区对海洋生态系统产生重大影响,影响移动宏观生物.
- 全球变暖预计将进一步减少海洋溶解氧.
研究的目的:
- 构建热带海洋地区溶解氧度的50年时间序列.
- 分析过去五十年来氧气水平的变化.
- 为了研究低氧区的垂直扩张.
主要方法:
- 用最近的测量增加历史溶解氧数据库.
- 从选定的热带海洋地区分析溶解氧度数据.
- 创建50年的时间序列来跟踪氧气趋势.
主要成果:
- 在东部热带大西洋和赤道太平洋观察到的中等深度低氧区的垂直扩张.
- 溶解氧的下降速率为每公斤每年0.09至0.34微摩尔,在300至700米层.
- 在过去的50年里,海洋溶解氧的显著下降.
结论:
- 热带海洋的低氧区正在垂直扩张.
- 氧气水平下降对海洋生物和沿海经济构成威胁.
- 观察到的趋势与气候模型预测减少海洋氧气的趋势一致.
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