Chen Annan, Zhao Chuanfeng, Zhang Haotian, Yang Yikun, Li Jiefeng
Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, 100871, China.
Institute of Carbon Neutrality, Peking University, Beijing, 100871, China.
Nat Commun. 2024 Sep 6;15(1):7816. doi: 10.1038/s41467-024-52255-z.
Aerosols and Surface Albedo (SA) are critical in balancing Earth's energy budget. With the changes of surface types and corresponding SA in recent years, an intriguing yet unresolved question emerges: how does Aerosol Direct Radiative Effect (ADRE) and its warming effect (AWE) change with varying SA? Here we investigate the critical SA marking ADRE shift from negative to positive under varying aerosol properties, along with the impact of SA on the ADRE. Results show that AWE often occurs in mid-high latitudes or regions with high-absorptivity aerosols, with critical SA ranging from 0.18 to 0.96. Thinner and/or more absorptive aerosols more readily cause AWE statistically. In regions where the SA trend is significant, SA has decreased at -0.012/decade, causing a -0.2 ± 0.17 W/m²/decade ADRE change, with the most pronounced changes in the Northern Hemisphere during June-July. As SA declines, we highlight enhanced ADRE cooling or reduced AWE, indicating aerosols' stronger cooling, partly countering the energy rise from SA reduction.
气溶胶与地表反照率（SA）对于平衡地球能量收支至关重要。近年来，随着地表类型及相应地表反照率的变化，一个有趣但尚未解决的问题出现了：气溶胶直接辐射效应（ADRE）及其变暖效应（AWE）如何随变化的地表反照率而改变？在此，我们研究了在不同气溶胶特性下标志着ADRE从负向正转变的关键地表反照率，以及地表反照率对ADRE的影响。结果表明，AWE通常发生在中高纬度地区或具有高吸收性气溶胶的区域，关键地表反照率范围为0.18至0.96。从统计学角度来看，更薄和/或吸收性更强的气溶胶更容易引发AWE。在地表反照率趋势显著的区域，地表反照率以-0.012/十年的速率下降，导致ADRE产生-0.2±0.17W/m²/十年的变化，其中6-7月在北半球变化最为明显。随着地表反照率下降，我们强调ADRE冷却增强或AWE减弱，这表明气溶胶的冷却作用更强，部分抵消了因地表反照率降低而增加的能量。
