Needs and challenges of optical atmospheric monitoring on the background of carbon neutrality in China

The achievement of the targets of coordinated control of PM2.5 and O3 and the carbon peaking and carbon neutrality depend on the development of pollution and greenhouse gas monitoring technologies.Optical monitoring technology,based on its technical characteristics of high scalability,high sensitivity and wide-targets detection,has obvious advantages in pollution/greenhouse gases monitoring and has become an important direction in the development of environmental monitoring technology.At present,a system of environmental optical monitoring technology with differential optical absorption spectroscopy(DOAS),cavity ring-down spectroscopy(CRDS),light detection and ranging(LIDAR),laser heterodyne spectroscopy(LHS),tunable diode laser absorption spectroscopy(TDLAS),fourier transform infrared spectroscopy(FTIR)and fluorescence assay by gas expansion(FAGE)as the main body has been established.However,with the promotion of“reduction of pollution and carbon emissions”strategy,there have been significant changes in the sources of pollution/greenhouse gases,emission components and emission concentrations,which have put forward new and higher requirements for the development of monitoring technologies.In the future,we should pay more attention to the development of new optical monitoring techniques and the construction of stereoscopic monitoring system,the interdisciplinarity(among mathematics,physics,chemistry and biology,etc.),and the monitoring of greenhouse gases and research on atmospheric chemistry.

A review of Space-Air-Ground integrated remote sensing techniques for atmospheric monitoring

Currently,the three-dimensional(3D)distribution and characteristics of air pollution cannot be understood based on the application of any single atmospheric monitoring technology.Long-term,high-precision and large-scale 3D atmospheric monitoring might become practical by combining heterogeneous modern technologies;for this purpose,the SpaceAir-Ground integrated system is a promising concept.In this system,optical remote sensing technologies employing fixed or mobile platforms are used as the main means for groundbased observations.Tethered balloons,unmanned aerial vehicles(UAV)and airborne platforms serve as the air-based observation segment.The final part,satellite remote sensing,corresponds to space-based observations.Aside from obtaining the 3D distribution of air pollution,research on emission estimation and pollution mechanisms has been extensively implemented based on the strengths of this system or some portion of it.Moreover,further research on the fusion of multi-source data,optimization of inversion algorithms,and coupling with atmospheric models is of great importance to the realization of this system.

Atmospheric environment monitoring technology and equipment in China:A review and outlook

Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control purposes.This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years.China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort.The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been initiated.It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.

Research on Decision Support System (DSS) of Atmospheric Environment Management in Anhui Province Based on Air Quality Forecasting

With the atmospheric stereoscopic monitoring, air quality forecasting and decision of environment management as the main line, and comprehensive management system as the guidance, five platforms including infrastructure, technological support, monitoring and early monitoring, decision support and information services were established. These platforms have 15 subsystems, including stereoscopic monitoring network, visual business consultation, high-performance computing environment, comprehensive management of atmospheric data, emission inventories of pollu-tion sources, evaluation tools of atmospheric models, monitoring and management of air pollution, forecasting and early warning of air quality, diag-nostic analysis of atmospheric environment, tracking of air pollution sources, emergency management of air pollution, conformity management of air quality, comprehensive display of information, releasing of information to external networks, and releasing of information by mobile networks. The decision support system （DSS） of atmospheric environment management could realize an integration business system of 11 air quality forecast - heavy pollution weather warning - diagnosis of pollution causes （dynamic analysis of pollution sources） -air quality conformity planning （air pollu-tion emergency management） -evaluation of forecasting and warning results （evaluation pf management measures） -air quality forecasting＂ and provide the technical support for the prevention and control of atmosphere pollution in Anhui province.

Application of Regularized Logistic Regression and Artificial Neural Network Model for Ozone Classification across El Paso County, Texas, United States

This paper focuses on ozone prediction in the atmosphere using a machine learning approach. We utilize air pollutant and meteorological variable datasets from the El Paso area to classify ozone levels as high or low. The LR and ANN algorithms are employed to train the datasets. The models demonstrate a remarkably high classification accuracy of 89.3% in predicting ozone levels on a given day. Evaluation metrics reveal that both the ANN and LR models exhibit accuracies of 89.3% and 88.4%, respectively. Additionally, the AUC values for both models are comparable, with the ANN achieving 95.4% and the LR obtaining 95.2%. The lower the cross-entropy loss (log loss), the higher the model’s accuracy or performance. Our ANN model yields a log loss of 3.74, while the LR model shows a log loss of 6.03. The prediction time for the ANN model is approximately 0.00 seconds, whereas the LR model takes 0.02 seconds. Our odds ratio analysis indicates that features such as “Solar radiation”, “Std. Dev. Wind Direction”, “outdoor temperature”, “dew point temperature”, and “PM10” contribute to high ozone levels in El Paso, Texas. Based on metrics such as accuracy, error rate, log loss, and prediction time, the ANN model proves to be faster and more suitable for ozone classification in the El Paso, Texas area.

Highly-sensitive NO,NO2,and NH3 measurements with an open-multipass cell based on mid-infrared wavelength modulation spectroscopy

A compact prototype based on mid-infrared wavelength modulation spectroscopy（WMS）is developed for the simul-taneous monitoring of NO,NO2,and NH3 in the urban area.Three quantum cascade lasers（QCLs）with central frequencies around 1900.0 cm^-1,1600.0 cm^-1,and 1103.4 cm^-1are used for NO,NO2,and NH3detections,respectively,by timedivision multiplex.An open-path multi-pass cell of 60-m optical path length is applied to the instrument for high sensitivity and reducing the response time to less than 1 s.The prototype achieves a sub-ppb detection limit for all the three target gases with an average time of about 100 s.The instrument is installed in the Jiangsu environmental monitoring center to conduct performance tests on ambient air.Continuous 24-hour measurements show good agreement with the results of a reference instrument based on the chemiluminescence technique.

CARBONIZED FIBROUS RESIN AS A NEW SORBENT FOR SAMPLING POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) IN AMBIENT AIR

A new sampling method of ambient air analysis using carbonized fibrous resin as a sorbent for polycyclic aromatic hydrocarbons (PAHs) was reported. The physical and chemical properties of the carbonized fibrous resins were measured. The sample pretreatment with ultrasonic extraction and subsequent clean-up elution through a silica gel column was optimized. The suitable ultrasonic extraction conditions were selected as follows: resin weight was 1.5 g, ultrasonic extraction time 20 min, volume of extraction solvent 100 ml and extraction operation times 2~3. The concentrated extractable organic matter was submitted to next step of clean-up procedure of adsorption chromatography on silica gel column/n-hexane and a mixture of dichloromethene:n-hexane solution 2:3 (v/v). The PAHs fractions in the real samples from Changzhou, China were particularly analyzed using GC-MS data system and the data of mass spectra, retention times and scan numbers of the real samples were compared with that of the standards of 16 PAHs listed by the US EPA as 損riority pollutants?of the environment. The analysis of the real samples indicates that the carbonized fibrous resin is a good sorbent. The pretreatment of samples of ambient air with carbonized fibrous resin as a sorbent for PAHs is proved to be reliable and might be used for the procedure of the determination of PAHs in atmospheric environment.

Advances in coastal ocean boundary layer detection technology and equipment in China

Accurate and comprehensive knowledge of the atmospheric environment and its evolution within the coastal ocean boundary layer are necessary for understanding the sources,chemical mechanisms,and transport processes of air pollution in land,sea,and atmosphere.We present an overview of coastal ocean boundary layer detection technology and equipment in China and summarize the progress and main achievements in recent years.China has developed a series of coastal ocean boundary layer detection technologies,including Light Detection and Ranging(LIDAR),turbulent exchange analyzer,air-sea flux analyzer,stereoscopic remote sensing of air pollutants,and oceanic aerosol detection equipment to address the technical bottleneck caused by harsh environmental conditions in coastal ocean regions.Advances in these technologies and equipment have provided scientific assistance for addressing air pollution issues and understanding land-sea-atmosphere interactions over coastal ocean regions in China.In the future,routine atmospheric observations should cover the coastal ocean boundary layer of China.