Particle resupply in the lower atmosphere

• 成果类型: Editorial Material
• 署名作者: Coe, Hugh
• 署名单位: University of Manchester; UK Research & Innovation (UKRI); Natural Environment Research Council (NERC); NERC National Centre for Atmospheric Science; University of Manchester
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13835
• DOI: 10.1126/science.adq4711
• 发表日期: 2024-07-12
• 页码: 144-144
• 关键词: troposphere

摘要

New atmospheric particles form when the stratosphere intrudes into the troposphere Aerosol particles smaller than 1 mm in diameter are ubiquitous in the troposphere, the lowest part of Earth's atmosphere responsible for weather and a major part of the climate system. They act as condensation sites for water vapor from which cloud droplets grow and hence, are part of the hydrological cycle. Precipitation removes these particles on timescales of a few days to weeks. A major challenge is understanding the processes that supply new particles to the atmospheric system. Although several mechanisms have previously been described, they do not fully explain observations in the mid-troposphere of nanometer-sized particles, indicative of new particle formation (1). On page 210 of this issue, Zhang et al. (2) report that new particle events strongly correlate with intrusions of dry air from the stratosphere, when mixed with tropospheric air. These occurrences may underlie the resupply of new particles to these regions of the atmosphere.