美国国家气象研究中心Laura L. Pan团队发现，东亚夏季风向平流层下层输送大量极短寿命的有机氯物质
亚洲夏季风中的深层对流是将污染物从行星边界层提升到对流层的重要输送过程。这一过程能够有效地向平流层注入活性物质，如消耗臭氧的氯化极短寿命物质(Cl-VSLSs)。过去对与亚洲夏季风相关的对流输送的研究主要集中在南亚夏季风上。
本研究报告的航空观测表明，东亚夏季风对流是将破纪录的消耗臭氧的Cl-VSLS(这些VSLS的平均有机氯~500 ppt)，输送到平流层底部的有效输送途径。这些独特的观测结果表明，在亚洲季风对流层上方平流层下层的VSLS总有机氯是以前报道的热带对流层上空的两倍多。
考虑到最近观测到的Cl-VSLS排放的增加，和全球变暖情况下东亚夏季风的持续加强，他们的结果强调，通过亚洲季风重新评估Cl-VSLS注入对平流层总氯收支的贡献是有必要的。
附：英文原文
Title: East Asian summer monsoon delivers large abundances of very-short-lived organic chlorine substances to the lower stratosphere
Author: Pan, Laura L., Atlas, Elliot L., Honomichl, Shawn B., Smith, Warren P., Kinnison, Douglas E., Solomon, Susan, Santee, Michelle L., Saiz-Lopez, Alfonso, Laube, Johannes C., Wang, Bin, Ueyama, Rei, Bresch, James F., Hornbrook, Rebecca S., Apel, Eric C., Hills, Alan J., Treadaway, Victoria, Smith, Katie, Schauffler, Sue, Donnelly, Stephen, Hendershot, Roger, Lueb, Richard, Campos, Teresa, Viciani, Silvia, D’Amato, Francesco, Bianchini, Giovanni, Barucci, Marco, Podolske, James R., Iraci, Laura T., Gurganus, Colin, Bui, Paul, Dean-Day, Jonathan M., Millán, Luis, Ryoo, Ju-Mee, Barletta, Barbara, Koo, Ja-Ho, Kim, Joowan, Liang, Qing, Randel, William J., Thornberry, Troy, Newman, Paul A.
Issue&Volume: 2024-3-14
Abstract: Deep convection in the Asian summer monsoon is a significant transport process for lifting pollutants from the planetary boundary layer to the tropopause level. This process enables efficient injection into the stratosphere of reactive species such as chlorinated very-short-lived substances (Cl-VSLSs) that deplete ozone. Past studies of convective transport associated with the Asian summer monsoon have focused mostly on the south Asian summer monsoon. Airborne observations reported in this work identify the East Asian summer monsoon convection as an effective transport pathway that carried record-breaking levels of ozone-depleting Cl-VSLSs (mean organic chlorine from these VSLSs ~500 ppt) to the base of the stratosphere. These unique observations show total organic chlorine from VSLSs in the lower stratosphere over the Asian monsoon tropopause to be more than twice that previously reported over the tropical tropopause. Considering the recently observed increase in Cl-VSLS emissions and the ongoing strengthening of the East Asian summer monsoon under global warming, our results highlight that a reevaluation of the contribution of Cl-VSLS injection via the Asian monsoon to the total stratospheric chlorine budget is warranted.
DOI: 10.1073/pnas.2318716121
Source: https://www.pnas.org/doi/abs/10.1073/pnas.2318716121