自1980年以来,陆地和海洋二氧化碳流量的区域变化
P Bousquet1, P Peylin, P Ciais
1Laboratoire des Sciences du Climat et de l'Environnement (LSCE), F-91198 Gif-sur-Yvette Cedex, France. pbousquet@cea.fr
Science (New York, N.Y.)
|November 18, 2000
概括
全球碳平衡的变化显示,陆地流动的变化是海洋流动的两倍. 热带地区主导了20世纪80年代的碳变化,而北方地区在20世纪90年代处于领先地位.
科学领域:
- 地球系统科学 地球系统科学
- 大气化学 大气化学
- 生态生态学 生态生态学
背景情况:
- 大气中的二氧化碳 (CO2) 是一个关键的温室气体.
- 了解区域碳平衡对于减缓气候变化至关重要.
- 长期的二氧化碳测量为碳循环研究提供了有价值的数据.
研究的目的:
- 用大气二氧化碳测量推断海洋和大陆区域碳平衡的年度变化.
- 量化陆地和海洋碳流的变化.
- 确定跨年碳平衡随时间变化的主要贡献者的转变.
主要方法:
- 对20年的大气二氧化碳测量 (1980-1998) 应用一个反向模型.
- 分析来自海洋和陆地生态系统的区域碳流.
- 陆地和海洋沉之间碳流变量的比较.
主要成果:
- 全球陆地碳流在1980年至1998年间的变化大约是海洋流的两倍.
- 热带土地生态系统是20世纪80年代跨年碳平衡变化的主要驱动因素.
- 北部中高度陆地生态系统成为1990年至1995年碳平衡变化的主要贡献者.
- 与1989-1990年相比,1992-1993年北美地区的碳吸收量显著增加.
结论:
- 与海洋相比,陆地生态系统在碳流中表现出更高的年间变化.
- 全球碳平衡变化的主要驱动因素在过去二十年中在地理上发生了转变.
- 区域分析,如北美增强的碳吸收,强调了碳循环的动态性质.
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