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Updated: May 23, 2026
07:14
Automated, High-resolution Mobile Collection System for the Nitrogen Isotopic Analysis of NOx
Published on: December 20, 2016
[Comparison of NO2 slant columns between two ground-based MAX-DOAS]
Jin Xu1, Pin-hua Xie, Fu-qi Si
1Key Laboratory of Environmental Optical & Technology, Anhui Institute of Optics and Fine Mechanics, Hefei 230031, China. jxu@aiofm.ac.cn
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|April 20, 2012
Summary
Comparing two ground-based multi-axis DOAS instruments for nitrogen dioxide (NO2) slant columns revealed good agreement at lower viewing angles and during specific daytime hours. Visible range measurements offered superior results compared to UV.
Area of Science:
- Atmospheric chemistry
- Spectroscopy
- Remote sensing
Context:
- Ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) instruments are crucial for monitoring atmospheric pollutants.
- Accurate NO2 measurements are vital for air quality assessment and climate studies.
Purpose:
- To compare the performance of two MAX-DOAS instruments (JAMASTEC and AIOFM) for NO2 slant column retrieval.
- To evaluate the impact of viewing angles, time of day, and spectral range on measurement agreement.
Summary:
- Adjusted integral time improved signal-to-noise ratio compared to fixed settings.
- Good agreement (correlation coefficient 0.995) was observed between instruments at lower viewing angles, degrading at higher angles.
- Measurements between 9 am and 5 pm showed lower deviation (12% at 20 degrees).
- Visible spectral range results were superior to UV, with over 60% decrease in fit residuals and good agreement with UV data.
Impact:
- Provides insights into instrument inter-comparison for NO2 monitoring.
- Highlights the importance of optimal settings (integral time, viewing angles) for accurate atmospheric measurements.
- Suggests visible range measurements are more reliable for NO2 retrieval using MAX-DOAS.
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