在太平洋上部,南部翻转循环的减速
Michael J McPhaden1, Dongxiao Zhang
1NOAA/Pacific Marine Environmental Laboratory, Seattle, Washington 98115, USA. mcphaden@pmel.noaa.gov
Nature
|February 8, 2002
概括
太平洋温度影响气候和海洋生物. 观测显示,自20世纪70年代以来,海洋循环的放缓,减少了冷水上流和增加海面温度.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 海洋生物学 海洋生物学
背景情况:
- 十年来太平洋温度波动显著影响北美气候和海洋生态系统.
- 驱动这些温度变化的精确物理机制仍然不完全理解.
- 目前的理论表明,热带和亚热带地区之间的南部翻转循环 (MOC) 起着关键作用.
研究的目的:
- 为了研究太平洋南部翻转循环的长期趋势.
- 为了确定循环变化对赤道上游和海面温度的影响.
- 评估改变循环对海洋二氧化碳排放的后果.
主要方法:
- 对过去50年的观测数据进行分析.
- 量化南部翻转循环的变化.
- 测量赤道上游水量和海面温度趋势.
主要成果:
- 自20世纪70年代以来,太平洋的南部翻转循环已经减速.
- 赤道上游流量减少了大约25% (从47 x 10^6减少到35 x 10^6 m^3 s^-1).
- 这种减少与赤道海面温度上升0.8°C和减少二氧化碳排放有关.
结论:
- 观察到的MOC减速是近期全球变暖和赤道太平洋二氧化碳流量变化的主要驱动因素.
- 海洋循环的变化对海洋生态系统和全球气候调节有深远的影响.
- 需要进一步的研究才能充分理解海洋循环,温度和大气中的CO2之间的反机制.
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