Long‐Term Measurements of CO₂, CH₄, and Isotopic Ratios of CO₂ in the Western Pacific: Trends, Variations, and Implications

Journal of Geophysical Research Atmospheres, Journal Year: 2025, Volume and Issue: 130(8)

Published: April 15, 2025

Abstract Carbon dioxide (CO 2 ) and methane (CH 4 are major contributors to climate change, increasing radiative forcing global warming. This study investigates temporal variations of CO CH levels, along with isotopic ratios, at two western Pacific background sites: Lulin Atmospheric Background Station (LLN, 2,862 m ASL) in central Taiwan since August 2006, representing the free troposphere, Dongsha Island (DSI, 8 South China Sea March 2010, sea‐level conditions. Mean growth rates , δ 13 C‐CO LLN, DSI, Mauna Loa (MLO) were found similar over monitoring period until 2019, whereas 18 O‐CO showed unclear trend. Seasonal patterns LLN DSI reflect distinct influences from different regions. At daytime photosynthesis reduced rose afternoon caused by associated upslope valley breezes. We also observed an enlarging diurnal amplitude a significant large rate 9.2 ppb yr −1 afternoon, which was plausibly owing intensified winds LLN. Based on measurements backward trajectories during nighttime, Southeast Asian biomass burning enhanced 1.5 ppm (+0.4%) 15.4 (+0.8%) spring. Concentration weighted trajectory identifies potential source areas westerlies passing through southern Thailand, contributions Asia as result mixing air Sea.

Language: Английский

Comprehensive Two‐Dimensional Gas Chromatography–Mass Spectrometry for the Analysis of Atmospheric Particulate Matter

Rapid Communications in Mass Spectrometry, Journal Year: 2025, Volume and Issue: 39(13)

Published: April 1, 2025

Atmospheric particulate matter (PM) is a complex mixture with wide range of sources, but only limited proportion can be identified by existing analytical techniques. Comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC-MS) couples the advantages on high resolution, sensitivity, and peak capacity chromatography, together mass accuracy acquisition frequency time-of-flight (TOFMS). GC GC-MS has been gradually applied analysis environmental organic pollutants. This review introduces principles MS discusses its application compounds in atmospheric PM last two decades, so as to provide an outlook future trends this research frontiers. The synthesizes findings for analyzing pollutants PM, covering operational coupling TOFMS enhance speed. significantly improved identification PM-associated offering superior separation, capacity, detection sensitivity. technique enabled discovery previously unresolvable enhanced source apportionment PM. Despite advantages, widespread studies hindered challenges such data processing, instrument cost, standardization issues. offers separation pollutants, making it invaluable applications. Emerging technologies, machine learning, will capabilities broaden

Language: Английский

The tandem cracking-oxidation of phthalate esters with high CO2 selectivity and reduced energy cost

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 158653 - 158653

Published: Dec. 1, 2024

Language: Английский