Atmospheric rivers (ARs) are filamentary conduits of intense water vapour transport in the extratropics, accounting for the majority of poleward moisture transport in the mid-latitudes and acting as a key precipitation source for coastal regions. How ARs have responded to climate change nevertheless remains uncertain. Here we use a series of coupled model experiments to show that there was little to no change in mean AR characteristics in 1920–2005 due to opposite but equal influences from industrial aerosols, which weaken ARs, and greenhouse gases (GHGs), which strengthen them. Despite little historical change, the simulations project steep intensification of ARs in the coming decades, including mean AR-driven precipitation increases of up to ~20 mm per month, as the influence of GHGs greatly outpaces that of industrial aerosols. We also investigate the extent to which future AR changes are dynamically and thermodynamically driven, highlighting the need to conceptualize AR change beyond the scaling of humidity with warming.

大气河流（ARs）是热带地区强烈水汽输送的丝状管道，占中纬度地区向极地水分输送的大部分，是沿海地区的主要降水源。然而，AR 如何应对气候变化仍不确定。在这里，我们使用一系列耦合模型实验表明，由于工业气溶胶（削弱 AR）和温室气体 (GHG) 的相反但相同的影响，1920-2005 年平均 AR 特性几乎没有变化，而温室气体 (GHG) 增强了它们. 尽管历史变化不大，但模拟预测未来几十年 AR 会急剧加剧，包括 AR 驱动的平均降水量每月增加约 20 毫米，因为温室气体的影响大大超过了工业气溶胶的影响。