通过树环识别城市碳排放峰值14C
Zhenchuan Niu1,2,3, Weijian Zhou1,4,5, Yunfei Huang1,5
1State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
Environmental science & technology
|September 18, 2024
概括
研究人员使用树环放射性碳 (C) 数据在北京和西安确定了城市碳排放峰值. 这种方法提供了一种新的方法,可以精确确定盆地城市的排放峰值.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 古气候学 古气候学
背景情况:
- 使用传统的燃料库存方法,很难准确识别城市碳排放峰值.
- 化石燃料中的放射性碳 (C) 耗尽允许大气中CO2测量以跟踪排放.
- 大气CO2提供了一个独特的追踪器,用于精确确定碳排放来源.
研究的目的:
- 为了确定中国两个主要城市,北京和西安的峰值碳排放量.
- 利用城市树环放射性碳 (Δ14C) 时间序列作为当地碳排放的代理.
- 建立一种新的观测方法,用于确定盆地环境中的城市碳排放峰值.
主要方法:
- 收集了2000-2019年间北京和西安的城市树林环 Δ14C 数据.
- 从树环数据中减去背景大气Δ14C以隔离局部Δ14C (Δ14C局部).
- 分析了 Δ14Clocal 的时间趋势和下降速度,以确定排放峰值.
主要成果:
- 在北京 (2010年) 和西安 (2013年) 确定了 Δ14Clocal 的最小值,表明这些年碳排放的峰值.
- 观测到树环 Δ14C 的下降速度的明显转折点,与排放峰值相关.
- 北京显示从6.4 ‰/年下降到3.6 ‰/年,而西安则从6.0 ‰/年下降到3.0 ‰/年.
结论:
- 城市树环 Δ14 C 分析成功地确定了北京和西安的不同碳排放峰值.
- 该方法提供了一种可靠的观测方法,用于在复杂的城市盆地环境中确定碳排放峰值.
- 这种技术为城市环境管理和气候变化减缓战略提供了有价值的数据.
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