South Asian monsoon and pollution Air pollution is growing fastest in monsoon-impacted South Asia. During the dry winter monsoon, the fumes disperse toward the Indian Ocean, creating a vast pollution haze. The fate of these fumes during the wet summer monsoon has been unclear. Lelieveld et al. performed atmospheric chemistry measurements by aircraft in the Oxidation Mechanism Observations campaign, sampling the summer monsoon outflow in the upper troposphere between the Mediterranean and the Indian Ocean. The measurements, supported by model calculations, show that the monsoon sustains a remarkably efficient cleansing mechanism in which contaminants are rapidly oxidized and deposited on Earth's surface. However, some pollutants are lofted above the monsoon clouds and chemically processed in a reactive reservoir before being redistributed globally, including to the stratosphere. Science, this issue p. 270 The South Asian monsoon removes some air pollution and disperses the rest. Air pollution is growing fastest in monsoon-affected South Asia. During the dry winter monsoon, the fumes disperse toward the Indian Ocean, creating a vast pollution haze, but their fate during the wet summer monsoon has been unclear. We performed atmospheric chemistry measurements by aircraft in the Oxidation Mechanism Observations campaign, sampling the summer monsoon outflow in the upper troposphere between the Mediterranean and the Indian Ocean. The measurements, supported by model calculations, show that the monsoon sustains a remarkably efficient cleansing mechanism by which contaminants are rapidly oxidized and deposited to Earth’s surface. However, some pollutants are lofted above the monsoon clouds and chemically processed in a reactive reservoir before being redistributed globally, including to the stratosphere.

中文翻译：

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南亚季风——污染泵和净化器

南亚季风和污染 在受季风影响的南亚，空气污染增长最快。在干燥的冬季季风期间，烟雾向印度洋扩散，形成了巨大的污染阴霾。在潮湿的夏季季风期间，这些烟雾的归宿尚不清楚。Lelieveld 等。在氧化机制观测活动中通过飞机进行大气化学测量，对地中海和印度洋之间的对流层上层的夏季季风流出进行采样。由模型计算支持的测量表明，季风维持了一种非常有效的清洁机制，在这种机制中，污染物会迅速氧化并沉积在地球表面。然而，一些污染物漂浮在季风云层上方，在反应性水库中进行化学处理，然后在全球重新分布，包括进入平流层。科学，这个问题 p。270 南亚季风消除了一些空气污染并驱散了其余部分。在受季风影响的南亚，空气污染增长最快。在干燥的冬季季风期间，烟雾向印度洋扩散，形成了巨大的污染阴霾，但在潮湿的夏季风期间，它们的命运尚不清楚。我们在氧化机制观测活动中通过飞机进行了大气化学测量，对地中海和印度洋之间的对流层上层的夏季季风流出进行了采样。由模型计算支持的测量，表明季风维持了一种非常有效的清洁机制，通过这种机制，污染物会迅速氧化并沉积到地球表面。然而，一些污染物在季风云层上方漂浮并在反应性水库中进行化学处理，然后在全球重新分布，包括进入平流层。