Inverse Relations Between Amounts of Air Pollution and Orographic Precipitation

Rosenfeld, Daniel; Dai, Jianlong; Yu, Xiangyao; Yao, Zhanyu; Xu, Xiaohong; Xing, Yongming; Du, Cheng

doi:10.1126/science.1137949

Cited by 270 publications

(185 citation statements)

References 9 publications

Supporting

Mentioning

181

Contrasting

Order By: Relevance

“…A possible positive feedback between reduced precipitation and accumulated aerosols over eastern central China has been reported by Zhao et al (2006). Rosenfeld et al (2007b) proposed that aerosol and orographic precipitation have an inverse relationship over central China. In contrast, the observational and modeling studies indicate when deep convective clouds are prevailing, the delay of precipitation can invigorate the storm dynamics by freezing super-cooled water transported aloft (Levin and Cotton, 2008).…”

Section: Introductionmentioning

confidence: 99%

Inter-Annual Variations of Cloud and Precipitation and their Possible Relationships with Surface Aerosols in Shanghai

Zhang

Duan

et al. 2015

Aerosol Air Qual. Res.

View full text Add to dashboard Cite

Aerosol-cloud-precipitation interactions have attracted much more attention for decades, but there still remain many uncertainties in assessing global climate. Long-term ground-based measurements of aerosol, cloud and precipitation in Shanghai were used to examine their inter-annual variations and possible relationships. During 1990-2010, the yearlyaveraged total cloud cover (TCC) and low cloud cover (LCC) decrease on average by 0.58% and 2.49% per year. LCC correlates to surface aerosols (e.g., PM 10 ), with a correlation coefficient (R) of 0.67. Aerosol optical depth (AOD), as an indicator of columnar aerosol loading, shows a non-significant correlation with cloud cover. The yearly-aggregated heavy and extreme rain days and their rainfall amount increase gradually. The moderate rain day enhances but its annual rainfall amount declines year by year, while the light rain exhibits an opposite pattern to the moderate rain. These results imply that local aerosols maybe exert somewhat enforcing on low cloud and light rain through possible entrainment or updraft that can bring up surface particles into free troposphere, whereas its influence to total cloud and precipitation is negligible at a small scale. Future studies are needed to ensure whether local aerosols to directly affect low cloud, and to explore how surface aerosols to enter into higher atmospheric layers and impact cloud and precipitation at larger scales.

show abstract

Section: Introductionmentioning

confidence: 99%

Inter-Annual Variations of Cloud and Precipitation and their Possible Relationships with Surface Aerosols in Shanghai

Zhang

Duan

et al. 2015

Aerosol Air Qual. Res.

View full text Add to dashboard Cite

show abstract

“…Meanwhile, Cu also displayed a significant positive correlation with Cr and Zn, indicating that the general contamination sources for these metals were primarily traffic and industrial activities [18]. Furthermore, it should be noted that Hg was not significantly correlated with all other heavy metals considered, indicating that there are some unique sources of Hg that are currently unknown.…”

Section: Correlation Coefficient Analysismentioning

confidence: 99%

“…To a certain extent, Pearson's correlation coefficient can be used to measure the degree of correlation between the metal data and can provide suggestive information regarding heavy metal sources and pathways [6,18]. The results of Pearson's correlation coefficients of heavy metals in urban dusts in Changchun are summarized in Table 4.…”

Section: Correlation Coefficient Analysismentioning

confidence: 99%

“…Children are usually exposed to greater amounts of dust than adults as a result of "pica" (the mouthing of non-food objects) and play behavior. Meanwhile, research indicates that dust transported and stored in the urban environment also has the potential to provide considerable loadings of heavy metals to receiving water and water bodies [18]. Therefore, several authors have stated that there is a growing need for increased knowledge, investigation, and assessment of trace metal contamination in urban dust [9,10].…”

mentioning

confidence: 99%

See 1 more Smart Citation

Assessment of Heavy Metals Contamination in Near-Surface Dust

Zhong¹,

Ge²,

Lu³

et al. 2015

Pol. J. Environ. Stud.

View full text Add to dashboard Cite

IntroductionThe continuous urbanization and industrialization that has occurred in many countries over the last few decades has been accompanied by unprecedented environmental changes. Several categories of contaminates, such as heavy metals [1,2] and polycyclic aromatic hydrocarbons (PAHs) [3], etc., are continuously emitted into the terrestrial environment, thus posing a great threat to human health [3][4][5]. Nowadays, more and more people dwell in urban areas. Therefore, the changes of urban environment are crucially important for city dwellers. Heavy metal pollution of urban Pol. J. Environ. Stud. Vol. 24, No. 4 (2015), 1817-1829 AbstractAs a result of the continuous urbanization and industrialization in China over the last few decades, heavy metals have been continuously emitted into urban environments and now pose serious threats to human health. In the present study, an extensive urban near-surface dust survey was conducted in Changchun, China, to evaluate the current status of heavy metal contamination in urban dust and to identify the potential sources. A total of 232 samples were collected and the levels of Cu, Pb, Zn, Cd, Hg, As, Cr, and the major elements were then determined. The results indicated that the urban dusts were enriched with metals, particularly Cu, Cd, Zn, Pb, and Hg. Principal component analysis (PCA) was employed to identify sources of heavy metals, and the results revealed distinctly different associations among the trace metals and the major elements in the urban dusts. The concentrations of Cr and As appeared to be controlled by natural factors. Cu and Pb were mainly from vehicle emissions. Zn primarily come from traffic sources, especially vehicle tires. Additionally, Hg primarily originated from coal combustion, while Cd was mainly associated with industrial sources. A revised pollution index for each metal and a Nemerow integrated pollution index (NIPI) of the seven metals were attributed to each sampling site to assess the degree of metal contamination. The results showed that the pollution indexes (PI) of each metal are not especially high. However, a significant degree of metal pollution exists in some urban dusts in Changchun, particularly for Cu, Cd, Zn, and As. The mean value of the Nemerow integrated pollution index (NIPI) of the seven metals also indicated that urban dusts in Changchun city were classified as having moderate levels of pollution. However, it should be noted that about 11% of all samples had a NIPI value above 3, suggesting a high level of contamination by metals. These findings indicate that more attention should be paid to metal pollution of the urban dusts in Changchun in the future.

show abstract

“…It also slows the mixed phase precipitation forming processes by decreasing the riming and growth rate of ice hydrometeors (Borys et al, 2003;Saleeby et al, 2008). Slowing the precipitation forming processes in shallow and short lived orographic clouds is expected to cause a net decrease in precipitation amount in the upwind slope of the mountains (Griffith et al, 2005), often with some compensation at the downwind slope Rosenfeld, 2004, 2005;Jirak and Cotton, 2005;Rosenfeld and Givati, 2006;Givati and Rosenfeld, 2007;Rosenfeld et al, 2007;Cotton et al, 2010;Yang et al, 2013).…”

Section: Introductionmentioning

confidence: 99%