持续变化的"背景"平流层气溶层和全球气候变化
S Solomon1, J S Daniel, R R Neely
1Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA), Earth System Research Laboratory, Boulder, CO 80305, USA. susan.solomon@colorado.edu
Science (New York, N.Y.)
|July 23, 2011
概括
高层层气溶不是恒定的,而是可变的,自2000年以来一直在增加. 这种增加造成了负辐射强迫,减少了全球变暖并影响了气候模型预测.
科学领域:
- 大气科学 大气科学
- 气候科学是气候科学.
- 地球系统科学 地球系统科学
背景情况:
- 以前被认为是恒定的平流层气溶层,现在被认为是持久变化的.
- 大火山爆发不是平流层气溶变化的唯一驱动因素.
研究的目的:
- 分析平流层气溶丰富度的最近趋势.
- 量化与观察到的平流层气溶变化相关的辐射强迫.
- 评估这些变化对全球变暖气候模型预测的影响.
主要方法:
- 对多个独立数据集的分析,包括近全球卫星气溶数据.
- 基于平流层气溶丰度变化的辐射强迫的计算.
- 观察到的气溶趋势与气候模型假设的比较.
主要成果:
- 自2000年以来,平流层气溶的丰度明显增加.
- 这种增加导致了大约0.1W/m2的负辐射强迫,减轻了最近的全球变暖.
- 历史数据 (1960-1990) 表明,进一步的负辐射强迫约为 -0.1 W/m2.
结论:
- 观察到平流层气溶的增加正在积极减少全球变暖.
- 不考虑这些气溶变化的气候模型可能会高估未来的辐射强迫和全球变暖.
- 这些气溶的持续存在或增加需要对气候变化预测进行调整.
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