The in-flight wavelength calibration for the Ozone Monitoring Instrument is discussed. The observed variability in the wavelength scale is two orders of magnitude larger than caused by temperature changes in the instrument. These wavelength variations are the result of rapid changes in time in the radiance levels during an individual observation in the presence of clouds or snow and ice. We have developed a data processing method to account and correct for these changes. In February 2005 this correction was implemented in the official data processing stream. We explain in detail how and how accurately this method works. Before correction, the error in the wavelength scale can be as much as a few tenths of a pixel; after correction it is mostly less than 1/100th of a pixel, which is the required preflight accuracy. This means that higher-level products such as the total column amounts of ozone, NO2, and SO2 are not significantly affected. It is expected that these wavelength variations will be observed in other hyperspectral Earth observation spectrometers and that the correction mechanism should apply equally well.
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http://dx.doi.org/10.1364/ao.45.003652 | DOI Listing |
Environ Sci Technol
January 2025
Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States.
Deployment of large numbers of low capital cost sensors to increase the spatial density of air quality measurements enables applications that build on mapping air at neighborhood scales. Effective deployment requires not only low capital costs for observations but also a simultaneous reduction in labor costs. The Berkeley Environmental Air Quality and CO Network (BEACON) is a sensor network measuring O, CO, NO, and NO, particulate matter (PM), and CO at dozens of locations in cities where it is deployed.
View Article and Find Full Text PDFSci Rep
January 2025
Shenyang Institute of Computing Technology, Chinese Academy of Sciences, Shenyang, 110168, Liaoning, China.
The problem of ground-level ozone (O) pollution has become a global environmental challenge with far-reaching impacts on public health and ecosystems. Effective control of ozone pollution still faces complex challenges from factors such as complex precursor interactions, variable meteorological conditions and atmospheric chemical processes. To address this problem, a convolutional neural network (CNN) model combining the improved particle swarm optimization (IPSO) algorithm and SHAP analysis, called SHAP-IPSO-CNN, is developed in this study, aiming to reveal the key factors affecting ground-level ozone pollution and their interaction mechanisms.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
College of Environment and Resources, College of Carbon Neutral, Zhejiang A & F University, Hangzhou 311300, China.
p-Phenylenediamines (PPDs) are widely used as antioxidants in numerous rubber products to prevent or delay oxidation and corrosion. However, their derived quinones (PPD-Qs), generated through reactions with ozone, are ubiquitous in the environment and raise significant health and toxicity concerns. This review summarizes the current state of knowledge on environmental distribution and fate, human exposure, and biological toxicity of PPDs and PPD-Qs, and makes recommendations for future research directions.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA. Electronic address:
PNPLA3-I148M genotype is the strongest predictive single-nucleotide polymorphism for liver fat. We examine whether PNPLA3-I148M modifies associations between oxidative gaseous air pollutant exposure (O) with i) liver fat and ii) multi-omics profiles of miRNAs and metabolites linked to liver fat. Participants were 69 young adults (17-22 years) from the Meta-AIR cohort.
View Article and Find Full Text PDFEnviron Pollut
January 2025
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China. Electronic address:
In recent years, ozone (O) pollution in many Chinese cities has worsened. Several cities have also experienced incidents where nocturnal O concentrations did not decrease as expected, and instead remained at high levels (above 50 ppb). However, there have been few detailed studies on the causes of these events.
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