Dataset Information

Anthropogenic Fingerprint Detectable in Upper Tropospheric Ozone Trends Retrieved from Satellite.

ABSTRACT: Tropospheric ozone (O₃) is a strong greenhouse gas, particularly in the upper troposphere (UT). Limited observations point to a continuous increase in UT O₃ in recent decades, but the attribution of UT O₃ changes is complicated by large internal climate variability. We show that the anthropogenic signal ("fingerprint") in the patterns of UT O₃ increases is distinguishable from the background noise of internal variability. The time-invariant fingerprint of human-caused UT O₃ changes is derived from a 16-member initial-condition ensemble performed with a chemistry-climate model (CESM2-WACCM6). The fingerprint is largest between 30°S and 40°N, especially near 30°N. In contrast, the noise pattern in UT O₃ is mainly associated with the El Niño-Southern Oscillation (ENSO). The UT O₃ fingerprint pattern can be discerned with high confidence within only 13 years of the 2005 start of the OMI/MLS satellite record. Unlike the UT O₃ fingerprint, the lower tropospheric (LT) O₃ fingerprint varies significantly over time and space in response to large-scale changes in anthropogenic precursor emissions, with the highest signal-to-noise ratios near 40°N in Asia and Europe. Our analysis reveals a significant human effect on Earth's atmospheric chemistry in the UT and indicates promise for identifying fingerprints of specific sources of ozone precursors.

SUBMITTER: Yu X

PROVIDER: S-EPMC11325641 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Anthropogenic Fingerprint Detectable in Upper Tropospheric Ozone Trends Retrieved from Satellite.

Yu Xinyuan X Fiore Arlene M AM Santer Benjamin D BD Correa Gustavo P GP Lamarque Jean-François JF Ziemke Jerald R JR Eastham Sebastian D SD Zhu Qindan Q

Environmental science & technology 20240802 32

Tropospheric ozone (O3) is a strong greenhouse gas, particularly in the upper troposphere (UT). Limited observations point to a continuous increase in UT O3 in recent decades, but the attribution of UT O3 changes is complicated by large internal climate variability. We show that the anthropogenic signal ("fingerprint") in the patterns of UT O3 increases is distinguishable from the background noise of internal variability. The time-invariant fingerprint ...[more]

PMID: 39092829

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Anthropogenic Fingerprint Detectable in Upper Tropospheric Ozone Trends Retrieved from Satellite.

Publications

Anthropogenic Fingerprint Detectable in Upper Tropospheric Ozone Trends Retrieved from Satellite.

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