基于陆地和大气的一致的美国碳汇估计.
S W Pacala1, G C Hurtt, D Baker
1Department of Ecology and Evolutionary Biology, Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ 08544, USA. Pacala@princeton.edu
Science (New York, N.Y.)
|June 26, 2001
概括
从1980年至1989年,美国作为一个重要的碳汇,每年吸收0.300.58百克的碳. 这一估计比以前的研究更大,包括非森林部门,并且与大气测量结果一致.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 生态生态学 生态生态学
背景情况:
- 精确估计碳汇对于了解全球碳循环动态至关重要.
- 之前对美国碳汇的研究在范围和方法上存在局限性.
- 1980年至1989年期间是评估碳捕集趋势的关键时间段.
研究的目的:
- 量化1980-1989年期间在美国境内的碳汇.
- 为了比较基于陆地的估计与基于大气的反转方法.
- 为了研究美国碳汇的稳定性,随着时间的推移.
主要方法:
- 基于陆地的碳流量估计,包括额外的过程和修订的组件流量.
- 使用基于二氧化碳度的追踪器-运输反转方法进行大气模型.
- 基于陆地和大气的沉估计的比较和验证.
主要成果:
- 据估计,美国每年碳沉降量在0.30至0.58百克之间 (1980-89).
- 土地净碳流量在每年0.37至0.71千克碳之间,占河流和商业出口.
- 基于土地的估计比以前的研究要大得多,约有一半在森林部门之外.
- 基于大气的反转结果与基于陆地的估计结果一致,在不确定性范围内.
- 美国的碳汇从1980-1989年到1990-1994年表现出相对稳定.
结论:
- 在1980年至1989年期间,相邻的美国充当了相当大的碳汇.
- 包括多种过程和非林业部门在内,提高了沉估计的准确性.
- 基于陆地和大气的方法提供了一致的,尽管不确定,估计美国的碳汇.
- 美国的碳汇在评估期间保持相对稳定.
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