关于半球间基根平价的观测证据
P K Patra1, M C Krol2, S A Montzka3
11] Department of Environmental Geochemical Cycle Research, JAMSTEC, Yokohama 236 0001, Japan [2] CAOS, Graduate School of Studies, Tohoku University, Sendai 980 8578, Japan.
Nature
|September 12, 2014
概括
北半球和南半球之间的基 (OH) 比率对于估计温室气体排放至关重要. 这项研究估计该比率为0.97±0.12,这表明一些排放估计可能过高.
科学领域:
- 大气化学 大气化学
- 气候科学 气候科学
- 环境监测 环境监测
背景情况:
- 基 (OH) 是主要的大气氧化剂,控制许多污染物和温室气体的寿命.
- 北半球 (NH) 和南半球 (SH) 之间的OH度的比率对于准确估计甲和氧化物等物种的排放至关重要.
- 目前对NH/SH OH比率的估计差异很大,这表明知识缺口很大.
研究的目的:
- 为了确定基 (OH) 度的更精确的NH/SH比.
- 改进对半球间运输及其对大气氧化剂分布的影响的理解.
- 评估NH/SH OH比对上下排放库存的影响.
主要方法:
- 使用甲基甲酸盐数据作为OH度的代理.
- 采用大气运输模型来模拟半球间的运输和排放.
- 优化了全球排放和平均OH丰度,以匹配地表和飞机网络的甲基甲测量.
主要成果:
- 建立了甲基甲的模型NH-SH梯度和模型NH/SH OH比率之间的线性关系.
- 在2004-2011年期间,估计NH/SH OH比为0.97±0.12.
- 证明甲基酸盐数据可以有效地限制NH/SH OH比率.
结论:
- 这项研究为NH/SH OH比率提供了有限的估计,改善了我们对大气氧化剂分布的理解.
- 结果表明,依赖NH/SH OH比率> 1的NH中氧化的自上而下的排放估计可能被高估.
- 这项研究强调了准确的OH分布对于可靠的排放计算的重要性.
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