大型原甲在结开始时爆发
Mikhail Mastepanov1, Charlotte Sigsgaard, Edward J Dlugokencky
1GeoBiosphere Science Centre, Physical Geography and Ecosystems Analysis, Lund University, Sölvegatan 12, 22362, Lund, Sweden.
Nature
|December 5, 2008
概括
北极湿地的甲排放量在土壤结期间显著增加,这是以前未知的现象. 这种"结爆发"可以与夏季的排放相比较,有助于解释北极高度的大气甲模式.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 地质物理学 地质物理学
背景情况:
- 陆地湿地是大气中甲的主要来源.
- 高度湿地对全球甲排放的贡献尚未完全理解.
- 在北极地区观察到的甲模式,特别是秋季后期的增加,缺乏明确的来源归因.
研究的目的:
- 在秋季结期间,调查高北极湿地的甲排放情况.
- 量化结排放相对于生长季节排放的意义.
- 为了提高大气甲模型对高北度的准确性.
主要方法:
- 延长每小时的甲流量测量到秋季末和冬季初.
- 在高北极环境中土壤结开始时收集的数据.
- 使用了3D大气化学和运输模型模拟.
主要成果:
- 甲排放量在生长季节后减少,但在土壤结期间显著增加.
- 发现结期的排放量大致相当于整个夏季的排放量.
- 纳入这些排放的模型模拟与60°N以北观察到的大气甲数据有了更好的一致性.
结论:
- 在结期期间,永久土相关的甲排放是北极甲释放的重要且以前被低估的组成部分.
- 这些发现有助于解释在高北度地区观察到的晚秋甲肩膀.
- 识别结爆发对于准确建模全球甲循环和气候变化影响至关重要.
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