Saltar al contenido principal

2015 Conference

del 24 al 27 de June del 2015

San Diego, CA

Interannual variability of summertime aerosol optical depth over East Asia during 2000–2011: a potential influence from El Niño Southern Oscillation

viernes, el 26 de junio de 2015 a las 18:00–19:30 PDT
Deutz
Type of Session

Poster Presentation

Abstract

Aerosols degrade air quality, perturb atmospheric radiation, and impact regional and global climate. Due to the rapid increase in anthropogenic emissions, aerosol loading over East Asia (EA) is markedly higher than other industrialized regions, which motivates a need to characterize the evolution of aerosols and understand the associated drivers. Based on the MISR satellite data during 2000–2011, a wave-like interannual variation of summertime aerosol optical depth (SAOD) is observed over the highly populated North China Plain (NCP) in East Asia. Specifically, the peak-to-trough ratio of SAOD ranges from 1.4 to 1.6, with a period of 3–4 years. This variation pattern differs apparently from what has been seen in EA emissions, indicating a periodic change in regional climate pattern during the past decade.

Investigations of meteorological fields over the region reveal that the high SAOD is generally associated with the enhanced Philippine Sea Anticyclone Anomaly (PSAA) which weakens southeasterlies over northeastern EA and depresses air ventilation. Alternatively, higher temperature and lower relative humidity are found to be coincident with reduced SAOD. The behavior of PSAA has been found previously to be modulated by the El Niño Southern Oscillations (ENSO), therefore ENSO could disturb the EA SAOD as well. Rather than changing coherently with the ENSO activity, the SAOD peaks over NCP are found to be accompanied by the rapid transition of El Niño warm to cold phases developed four months ahead. An index measuring the development of ENSO during January–April is able to capture the interannual variability of SAOD over NCP during 2000–2011. This finding indicates a need to integrate the large-scale periodic climate variability in the design of regional air quality policy.

Primary Contact

Yikun Liu, Master, University of Pennsylvania

Presenters

Yikun Liu, University of Pennsylvania
E-mail address (preferred) or phone number
Title of paper

Interannual variability of summertime aerosol optical depth over East Asia during 2000–2011: a potential influence from El Niño Southern Oscillation

Co-Authors

Junfeng Liu, Doctor, Peking University
Shu Tao, Peking University

Chair, Facilitator, Or Moderators

Discussants

Workshop Leaders

Cargando…