自2000年以来地球能量失衡变化的观测评估
Norman G Loeb1, Seung-Hee Ham2, Richard P Allan3
1NASA Langley Research Center, Hampton, VA 23681-2199 USA.
概括
地球的能量不平衡翻了一番,加速了气候变暖. 卫星数据显示,由于云层变化和海面温度上升,吸收的太阳辐射和输出的长波辐射增加.
科学领域:
- 气候科学 气候科学
- 地球系统科学 地球系统科学
- 大气物理学 大气物理学
背景情况:
- 地球的能量不平衡,气候变化的关键指标,已经显示出显著的转变.
- 之前的研究已经分析了地球能源预算的组成部分,但最近的趋势需要更新评估.
研究的目的:
- 通过卫星观测,量化地球能量失衡的最近变化.
- 为了确定这些变化的驱动因素,特别是吸收太阳辐射 (ASR) 和输出长波辐射 (OLR).
- 研究这些趋势的半球和区域变化及其与云层和海面温度的关系.
主要方法:
- 来自云层和地球辐射能量系统 (CERES) 的卫星数据的分析.
- 计算吸收太阳辐射 (ASR) 和输出长波辐射 (OLR) 的趋势.
- 在不同时间段 (停滞,厄尔尼诺,厄尔尼诺后) 和半球的趋势比较.
主要成果:
- 在过去的二十年中,地球的能量不平衡从0.5 ± 0.2 Wm−2翻了一番,从0.5 ± 0.2 Wm−2增加到1.0 ± 0.2 Wm−2.
- 吸收太阳辐射 (ASR) 增加0.9 ± 0.3 Wm−2是主要的驱动因素,部分被输出长波辐射 (OLR) 增加0.4 ± 0.25 Wm−2所抵消.
- 亚热带和中度云的减少,特别是在太平洋上空,与吸收太阳辐射 (ASR) 和海面温度 (SST) 的上升有关.
结论:
- 观察到的变化表明气候变暖的稳步加速.
- 作为对海面温度 (SST) 升高的反应,云层覆盖的变化表明对气候变化有积极的反.
- 虽然有云反的影响,但不能排除辐射强迫或内部变异的贡献.
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