来自中国东部的CFC-11和相关化学物质排放量下降
Sunyoung Park1, Luke M Western2, Takuya Saito3
1Department of Oceanography, Kyungpook National University, Daegu, Republic of Korea.
Nature
|February 11, 2021
概括
2013年后,中国东部的三甲 (CFC-11) 排放量意外上升,但到2019年恢复到2013年之前的水平. 碳四化物和CFC-12的相关排放量也有所下降,这表明最近的CFC-11生产停止了.
科学领域:
- 大气化学
- 环境科学
- 臭氧层研究
背景情况:
- 臭氧破坏物质的全球排放,如三二甲 (CFC-11),在蒙特利尔议定书后减少.
- 从2013年开始,全球CFC-11排放量发生了意想不到的增长,中国东部被确定为主要来源.
研究的目的:
- 通过大气观测和模型模拟,调查来自中国东部的区域CFC-11排放.
- 量化中国东部的CFC-11和相关化合物的排放量和时间.
主要方法:
- 利用来自韩国戈山和日本哈特鲁马的高频大气分子分数观测.
- 使用大气化学运输模型来分析排放源.
- 量化CFC-11,四化碳 (CCl4) 和二甲 (CFC-12) 的排放.
主要成果:
- 2019年,中国东部的CFC-11排放量减少到5.0±1.0千克/年,恢复到2013年之前的水平.
- 与2014年至2017年的平均水平相比,排放量每年下降了10±3千克.
- 与CFC-11生产相关的CCl4和CFC-12排放量在CFC-11减少前一年到两年下降,这表明在2017-2018年停止生产.
结论:
- 在逐步淘汰后,中国东部的CFC-11产量逐渐下降.
- 由于最近的产量,中国东部的CFC-11储量增加了多达112千克.
- 中国的及时报告和行动很可能阻止了臭氧层恢复的重大延迟.
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