直接气溶效应的卫星推导和建模估计之间的一致性
1Center for International Climate and Environmental Research-Oslo (CICERO), Post Office Box 1129 Blindern, N-0318 Oslo, Norway. gunnar.myhre@cicero.uio.no
Science (New York, N.Y.)
|June 23, 2009
概括
这项研究将全球气溶模型与基于观察的估计相协调,发现直接气溶效应辐射强迫较弱. 最好的估计是 -0.3 W m(-2),解决了之前的差异.
科学领域:
- 气候科学 气候科学
- 大气化学 大气化学
- 辐射转移是指辐射转移.
背景情况:
- 直接的气溶效应显著影响地球的辐射平衡,IPCC第四次评估报告中的估计范围很大 (-0.9至-0.1W m(-2)).
- 全球气溶模型与基于观察的估计之间存在差异,影响了气候强迫的准确性.
- 人类产生的气溶,特别是黑碳,在气溶辐射强迫中起着至关重要的作用.
研究的目的:
- 调和全球气溶模型模拟和直接气溶效应的基于观察的估计之间的差异.
- 为了改进全球和年度平均辐射强迫估计,由于直接的气溶效应.
- 调查之前的辐射强迫评估中差异背后的物理原因.
主要方法:
- 开发了一个全球气溶模型,与基于观察的方法相一致.
- 调整了基于观察的方法,以与模型输出保持一致.
- 基于调和方法计算的全球和年度平均辐射强迫.
主要成果:
- 在全球气溶模型和调整的基于观察的估计之间实现了一致性.
- 确定了全球和年度平均辐射强迫比以前报告的更弱,最佳估计为 -0.3 W m(-2).
- 鉴定了与总人为气溶相比,人为黑碳 (吸收气溶) 的不成比例增加是早期差异的关键因素.
结论:
- 直接气溶效应的辐射强迫估计为-0.3 W m(-2),解决了先前的不确定性.
- 这种精细的估计提供了更准确的气溶气候相互作用的表示.
- 了解吸收黑碳等气溶的作用对于准确的气候建模至关重要.
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