调查城市地区二氧化碳模拟中的变化和错误来源
Cory R Martin1, N Zeng1,2, A Karion3
1Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA.
概括
精确的城市温室气体 (GHG) 监测需要了解运输和分散. 这项研究发现,气象建模中的错误,而不是排放库存,主要影响冬季城市二氧化碳 (CO2) 预测.
科学领域:
- 大气化学和物理大气化学和物理
- 城市气象学城市气象学
- 温室气体排放的建模.
背景情况:
- 城市温室气体 (GHG) 缓解需要精确的排放量化.
- 模拟城市交通和分散是具有挑战性的,因为表面异质性等复杂的因素.
- 温室气体估计中的错误通常归因于运输/分散,但排放量和分布也会有所贡献.
研究的目的:
- 在城市观测系统中评估模拟大气二氧化碳 (CO2) 分子的可预测性.
- 评估气象条件对二氧化碳估计的影响与排放清单对比.
- 确定城市温室气体监测模型中主要的错误来源.
主要方法:
- 采用了欧勒尔模型,将气象变量与大气CO2的被动追踪器结合在一起.
- 在华盛顿特区/巴尔的摩地区利用了四个现场塔站点 (三个城市,一个农村) 2016年2月数据.
- 将模型模拟与使用四种不同的格式化化石燃料排放库存和生物圈流量模型的观测结果进行比较.
主要成果:
- 总体而言,表现良好:在城市地区,模拟和观察到的平均CO2分子分数在1%以内达成一致.
- 每小时的差异可能超过10%,归因于复杂的气象条件,而不是库存变化.
- 平均绝对误差是排放库存中模拟的摩尔分数标准偏差的两倍,这表明气象学是主要的错误来源.
结论:
- 模型气象学错误,而不是流动先验,在冬季主导城市二氧化碳预测错误.
- 改善大气传输和分散模型对于提高温室气体估计准确性至关重要.
- 城市地区的大气传输错误发生在全天,这表明CO2观测应该通过气象数据进行过.
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