Development of new retrieval method of tropospheric ozone from MAX-DOAS measurements and its application to long-term MAX-DOAS measurements in China and Germany for the validation of satellite observations and model results of tropospheric ozone

开发基于 MAX-DOAS 测量的对流层臭氧新反演方法及其在中国和德国长期 MAX-DOAS 测量中的应用，以验证对流层臭氧的卫星观测和模型结果

• 批准号: 428994811
• 负责人: Dr. Yang Wang, Ph.D.
• 金额: --
• 依托单位: Forschungsgruppe Satellitenfernerkundung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/428994811?language=en
• 关键词: Development; new; retrieval; method; tropospheric

Tropospheric ozone (O3) plays an important role in controlling the tropospheric chemical composition through various reactions with OH radicals, CO, CH4, NOx, and hydrocarbons. It is a greenhouse gas and pollutant detrimental to human health and crop and ecosystem productivity. However the lack of observations of vertical profiles of tropospheric obscures studies on its impact on the environment, climate, health and ecosystems. Recently developed products of tropospheric ozone derived from satellite observations and chemical transport modelling have large uncertainties and urgently need credible measurements of vertical profiles of tropospheric ozone for validation. Multi axis DOAS (MAX-DOAS) is a state of the art ground-based remote sensing technique to retrieve tropospheric vertical profiles and columns of trace gases (e.g. NO2, BrO, SO2, HCHO, HONO, and CHOCHO) from UV and visible spectra of scattered sunlight. However due to the strong influence of stratospheric O3 on MAX-DOAS measurements, still no satisfactory algorithms for the retrieval of tropospheric ozone profiles from MAX-DOAS measurements exist. In our recent preliminary study, we found that this difficulty could be addressed by the use of external data of stratospheric ozone (Method 1) or by utilising the temperature dependence of the ozone absorption cross section (Method 2), and two corresponding retrieval algorithms of tropospheric ozone from MAX-DOAS measurements have been developed. In this study, we will further improve the Method 1 to make the retrieval independent from external data sets by the use of stratospheric ozone also derived from the MAX-DOAS measurements at high solar zenith angle. The improved method will be validated during two campaigns in China and Germany by comparing them with results from ozone sondes, O3 lidars, Fourier transform spectrometry as well as in-situ O3 measurements. The new method will be evaluated and further improved for situations of strong haze pollutions (low visibility) in China. Then the new method will be adapted and applied for the analysis of long-term measurements of several MAX-DOAS instruments located in Germany and China. A data base of tropospheric ozone profiles will be generated based on the MAX-DOAS measurements in the North China Plain region and Yangtze River delta region, China and in Mainz, Germany. The data base will be used to validate satellite products and model simulations of tropospheric ozone, and characterize its temporal-spatial variation, the effects of regional transport, and to identify sources of tropospheric ozone. In addition to method 1, also method 2 (utilising the temperature dependence of O3 absorptions) will be further improved.

对流层臭氧（O3）通过与OH自由基、CO、CH4、NOx和碳氢化合物的各种反应，在控制对流层化学成分中起着重要作用。它是一种温室气体和污染物，对人类健康、作物和生态系统的生产力有害。然而，由于缺乏对流层垂直剖面的观测，对对流层对环境、气候、健康和生态系统影响的研究变得模糊不清。最近开发的基于卫星观测和化学输运模拟的对流层臭氧产品具有很大的不确定性，迫切需要对流层臭氧垂直剖面的可靠测量以进行验证。多轴DOAS （MAX-DOAS）是一种最先进的地面遥感技术，用于从散射阳光的紫外和可见光谱中检索对流层垂直剖面和微量气体柱（例如NO2， BrO, SO2， HCHO， HONO和CHOCHO）。然而，由于平流层臭氧对MAX-DOAS测量的强烈影响，目前还没有令人满意的算法从MAX-DOAS测量数据中检索对流层臭氧廓线。在我们最近的初步研究中，我们发现这一困难可以通过使用平流层臭氧的外部数据（方法1）或利用臭氧吸收截面的温度依赖性（方法2）来解决，并且已经开发了两种相应的从MAX-DOAS测量中检索对流层臭氧的算法。在本研究中，我们将进一步改进方法1，利用高太阳天顶角MAX-DOAS测量得到的平流层臭氧，使反演独立于外部数据集。改进后的方法将在中国和德国的两次活动中进行验证，将其与臭氧探空仪、臭氧激光雷达、傅立叶变换光谱以及原位臭氧测量的结果进行比较。新方法将在中国强雾霾污染（低能见度）的情况下进行评估和进一步改进。然后将新方法应用于德国和中国的几台MAX-DOAS仪器的长期测量分析。利用MAX-DOAS在中国华北平原地区、长江三角洲地区和德国美因茨的测量数据建立对流层臭氧剖面数据库。该数据库将用于验证对流层臭氧的卫星产品和模式模拟，表征其时空变化、区域运输的影响，并确定对流层臭氧的来源。除了方法1之外，方法2（利用O3吸收的温度依赖性）也将得到进一步改进。