不检测的会计:适用于卫星氨观测的应用
Evan White1,2, Mark W Shephard1, Karen E Cady-Pereira3
1Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada.
概括
这项研究引入了一种方法,用于准确分析卫星对大气氨 (NH3) 的测量,特别是当信号较弱时. 对未被检测的测量进行正确的核算可以提高数据的准确性,特别是在低度区域.
科学领域:
- 大气科学 大气科学
- 遥感 遥感 遥感 遥感
- 环境监测 环境监测
背景情况:
- 卫星对氨 (NH3) 等较小大气物种的测量通常包含在传感器检测极限以下的信号.
- 没有解释这些.
- 没有检测到的非检测.
研究的目的:
- 开发和应用一种方法来明确识别和核算次检测限度卫星测量.
- 为了提高大气物种带有弱光谱信号的卫星平均数据的准确性.
- 评估非检测对来自卫星观测的氨 (NH3) 度数据的影响.
主要方法:
- 利用来自卫星信号的信息内容来识别非检测.
- 采用一致的方法来考虑这些已识别的非检测结果.
- 实施CRIS快速物理检索 (CFPR) 氨产品的方法.
主要成果:
- 在高氨 (NH3) 排放区域 (>7.5 ppbv),非检测不频繁 (<5%) 并对平均值产生小影响 (<5%下降).
- 在低氨 (NH3) 度区域 (<1 ppbv),非检测结果可以超过70%的测量结果.
- 考虑到低度地区的非检测,可以将年平均值降低50%以上,使分布与表面观测保持一致.
结论:
- 开发的方法通过处理未检测到的测量,为氨 (NH3) 提供了更现实的平均数据集.
- 准确处理未被检测到的物质对于可靠的基于卫星的大气组成研究至关重要,特别是对于信号较弱的物种.
- 这些发现强调了未被检测到的数据对卫星来源的氨 (NH3) 度在环境水平较低的地区的重大影响.
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