Key Role of Arctic Sea‐Ice in Subseasonal Reversal of Early and Late Winter PM _2.5 Concentration Anomalies Over the North China Plain

Geophysical Research Letters, Год журнала: 2023, Номер 50(4)

Опубликована: Фев. 24, 2023

Abstract The PM 2.5 (fine particulate matter with diameter ≤2.5 μm) concentration anomalies over the North China Plain (NCP) in early and late winter sometimes show a subseasonal reversal, which brings great challenge for precise control of air pollution, mechanisms are not well understood. This paper reveals key role Barents Sea sea‐ice this reversal. In winter, negative Scandinavian‐like pattern causes an anticyclonic anomaly Northeast Asia thus leads to positive NCP. addition, anomalous warm advection associated Atlantic Oscillation‐like accelerates loss Sea, especially increases surface turbulent heating flux. These Polar/Eurasian‐like that induces cyclonic eventually NCP winter. Vice versa.

Язык: Английский

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Synergistic Effect of El Niño and Arctic Sea‐Ice Increment on Wintertime Northeast Asian Anomalous Anticyclone and Its Corresponding PM_2.5 Pollution

Journal of Geophysical Research Atmospheres, Год журнала: 2023, Номер 128(6)

Опубликована: Март 7, 2023

Abstract PM 2.5 pollution frequently occurs over the North China Plain (NCP) during early winter, which is usually modulated by northeast Asian anomalous anticyclone (NAAA). Research into NAAA and related has mainly focused on individual impact of El Niño or Arctic sea ice, with less analysis their synergistic effect. This study finds that October Barents–Kara Seas ice winter synergistically exert distinct remote influence via propagation Rossby waves finally deteriorate air quality NCP. More specifically, more Barents‐Kara in tends to cause a cooling there November, stimulates wave train thus strengthens NAAA. As result, weakened ventilation conditions stagnant support Further results reveal if are at same time, probability strong 57% associated NCP 43%, than only (0%) (14%). Considering key role NCP, we therefore construct simple linear model can skillfully predict lead time 1 month, shows good performance correlation coefficient up 0.61 raw

Язык: Английский

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Synoptic Weather Patterns and Atmospheric Circulation Types of PM2.5 Pollution Periods in the Beijing-Tianjin-Hebei Region

Atmosphere, Год журнала: 2023, Номер 14(6), С. 942 - 942

Опубликована: Май 27, 2023

The variation of PM2.5 concentration in the atmosphere is closely related to weather patterns. change pattern accompanied by corresponding atmospheric circulation characteristics. It necessary explore relationship between changes and characteristics during pollution periods. In this paper, Lamb-Jenkinson objective classification method applied classify daily circulation. periods are calculated rule obtained. Combined with physical parameter field (humidity, potential temperature, height), a typical period analyzed. Additionally, influence type on transport channel was results show that types study dominated A-type (anticyclonic), N-type (north), NE-type (northeast), indicating obvious seasonal differences, proportion C-type (cyclonic) increased significantly summer. During analysis from 2 4 January 2019, changed wind direction southeast wind, pressure gradient consistent trend field. Moreover, assisted verifying process conducive accumulation deposition pollutants external transport. research would provide theoretical support for prediction also supply technical basis establishment ecological compensation standards air environmental control.

Язык: Английский

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City Wind Impact on Air Pollution Control for Urban Planning with Different Time-Scale Considerations: A Case Study in Chengdu, China

Atmosphere, Год журнала: 2023, Номер 14(7), С. 1068 - 1068

Опубликована: Июнь 24, 2023

Economic development and fast growing urbanization in China have caused severe air pollution, with frequent pollution episodes endangering the health of inhabitants disturbing social activities, as an expanding metropolis, Chengdu has suffered ever since. The concentration variations main pollutants, such PM10, PM2.5 NO2, often show periodicity because meteorological impact anthropic display orientation discrepancies due to influences wind speed (WS), frequency pollutant sources. These features complicated mechanisms deepened difficulty control evaluation. WS significant on concentrations, quantifying influence which is high significance provides sustainable foundations for alleviation strategies. Different time-scale cycles (i.e., Diurnal, weekly, seasonal annual), along WS, frequency, spatial orientations urban areas, were analyzed this paper. Results that diurnal, annual remarkable, weekly cycle obvious by adding 16 orientations. direct impacts pollutants varying range 1.5–2.5 m/s, a remarkable diffusion effect once above 2.5 m/s. Over heavy hours transitional seasons, had more whereas not factor variations. For Chengdu, northeast suitable construct panel while pollutions northwest southwest below 1.5 north-northwest was worst. This work can provide guidance reference planning optimization environment protection cities quality considerations impacted city wind.

Язык: Английский

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Potential remote forcing of North Atlantic SST tripole anomalies on the seesaw haze intensity between late winter months in the North China plain: A case study

Atmospheric Science Letters, Год журнала: 2023, Номер 24(9)

Опубликована: Апрель 26, 2023

Abstract This study identified a prominent temporal seesaw haze intensity case that occurred between the late winter months of 2010 in North China Plain (NCP), featuring considerably suppressed January and enhanced adjacent month February 2011. We suggest dramatic alternations atmospheric oceanic anomalies played fundamental roles forming this case, rather than changes manmade emission anomalies. The 2011 was tied to an equivalent barotropic cyclonic anomaly dominated NCP its surroundings, which generated situ haze‐suppressed meteorology characterized by strengthened lower‐level northerly with cold dry conditions, as well elevated boundary layer height destabilized stratification. In stark contrast, connected anticyclonic anomaly, linking haze‐favourable opposite pronounced Atlantic sea surface temperature (SST) tripole anomalies, positive tropical mid‐latitudinal negative subtropical Atlantic, made significant contribution above‐mentioned case. Diagnostic analyses suggested SST were linked Oscillation (NAO)‐like pattern, acted source Rossby wave train generate concurrent over NCP. February, although NAO‐like pattern drastically dampened, centred southeast Yamal Peninsula critical role relaying impact thus inducing meteorology. Consequently, could exert effective modulation effect on generation intensity. proposed mechanism further verified using Community Earth System Model Large Ensemble Numerical Simulation (CESM‐LENS) datasets.

Язык: Английский

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Meteorological Impact on Dynamic Air Pollutant Concentrations in Different Timescales: Typical Case in Chengdu Megacity, China

Water Air & Soil Pollution, Год журнала: 2023, Номер 234(11)

Опубликована: Окт. 26, 2023

Язык: Английский

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Spatiotemporal Analysis and Source Attribution of Severe PM2.5 Pollution Episodes in Beijing during October-November 2023

Atmospheric Environment, Год журнала: 2024, Номер unknown, С. 121007 - 121007

Опубликована: Дек. 1, 2024

Язык: Английский

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