scholarly journals Characterization of Urban New Particle Formation in Amman—Jordan

Atmosphere ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 79 ◽  
Author(s):  
Tareq Hussein ◽  
Nahid Atashi ◽  
Larisa Sogacheva ◽  
Simo Hakala ◽  
Lubna Dada ◽  
...  
Keyword(s):  
Growth Rate ◽  
Eastern Mediterranean ◽  
Seasonal Pattern ◽  
Formation Rate ◽  
Particle Formation ◽  
New Particle Formation ◽  
Vapor Source ◽  
Back Trajectories ◽  
Pattern Maximum ◽  
The Mean

We characterized new particle formation (NPF) events in the urban background of Amman during August 2016–July 2017. The monthly mean of submicron particle number concentration was 1.2 × 104–3.7 × 104 cm−3 (exhibited seasonal, weekly, and diurnal variation). Nucleation mode (10–15 nm) concentration was 0.7 × 103–1.1 × 103 cm−3 during daytime with a sharp peak (1.1 × 103–1.8 × 103 cm−3) around noon. We identified 110 NPF events (≈34% of all days) of which 55 showed a decreasing mode diameter after growth. The NPF event occurrence was higher in summer than in winter, and events were accompanied with air mass back trajectories crossing over the Eastern Mediterranean. The mean nucleation rate (J10) was 1.9 ± 1.1 cm−3 s−1 (monthly mean 1.6–2.7 cm−3 s−1) and the mean growth rate was 6.8 ± 3.1 nm/h (4.1–8.8 nm/h). The formation rate did not have a seasonal pattern, but the growth rate had a seasonal variation (maximum around August and minimum in winter). The mean condensable vapor source rate was 4.1 ± 2.2 × 105 molecules/cm3 s (2.6–6.9 × 105 molecules/cm3 s) with a seasonal pattern (maximum around August). The mean condensation sink was 8.9 ± 3.3 × 10−3 s−1 (6.4–14.8 × 10−3 s−1) with a seasonal pattern (minimum around June and maximum in winter).

scholarly journals Atmospheric new particle formation characteristics in the Arctic as measured at Mount Zeppelin, Svalbard, from 2016 to 2018

2020 ◽  
Vol 20 (21) ◽  
pp. 13425-13441
Author(s):  
Haebum Lee ◽  
Kwangyul Lee ◽  
Chris Rene Lunder ◽  
Radovan Krejci ◽  
Wenche Aas ◽  
...  
Keyword(s):  
Growth Rate ◽  
Dimethyl Sulfide ◽  
Formation Rate ◽  
Production Capacity ◽  
Particle Formation ◽  
The Arctic ◽  
New Particle Formation ◽  
Low Loss ◽  
H2so4 Concentration ◽  
Average Formation

Abstract. We conducted continuous measurements of nanoparticles down to 3 nm size in the Arctic at Mount Zeppelin, Ny Ålesund, Svalbard, from October 2016 to December 2018, providing a size distribution of nanoparticles (3–60 nm). A significant number of nanoparticles as small as 3 nm were often observed during new particle formation (NPF), particularly in summer, suggesting that these were likely produced near the site rather than being transported from other regions after growth. The average NPF frequency per year was 23 %, having the highest percentage in August (63 %). The average formation rate (J) and growth rate (GR) for 3–7 nm particles were 0.04 cm−3 s−1 and 2.07 nm h−1, respectively. Although NPF frequency in the Arctic was comparable to that in continental areas, the J and GR were much lower. The number of nanoparticles increased more frequently when air mass originated over the south and southwest ocean regions; this pattern overlapped with regions having strong chlorophyll a concentration and dimethyl sulfide (DMS) production capacity (southwest ocean) and was also associated with increased NH3 and H2SO4 concentration, suggesting that marine biogenic sources were responsible for gaseous precursors to NPF. Our results show that previously developed NPF occurrence criteria (low loss rate and high cluster growth rate favor NPF) are also applicable to NPF in the Arctic.

scholarly journals Global analysis of continental boundary layer new particle formation based on long-term measurements

2018 ◽  
Author(s):  
Tuomo Nieminen ◽  
Veli-Matti Kerminen ◽  
Tuukka Petäjä ◽  
Pasi P. Aalto ◽  
Mikhail Arshinov ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Urban Areas ◽  
Global Analysis ◽  
Formation Rate ◽  
Particle Formation ◽  
Urban Environments ◽  
New Particle Formation ◽  
The World ◽  
Order Of Magnitude

Abstract. Atmospheric new particle formation (NPF) is an important phenomenon in terms of the global particle number concentrations. Here we investigated the frequency of NPF, formation rates of 10 nm particles and growth rates in the size range of 10–25 nm using at least one year of aerosol number size-distribution observations at 36 different locations around the world. The majority of these measurement sites are in the Northern Hemisphere. We found that the NPF frequency has a strong seasonal variability, taking place on about 30 % of the days in March–May and on about 10 % of the days in December–February. The median formation rate of 10 nm particles varies by about three orders of magnitude (0.01–10 cm−3 s−1) and the growth rate by about an order of magnitude (1–10 nm h−1). The smallest values of both formation and growth rates were observed at polar sites and the largest ones in urban environments or anthropogenically influenced rural sites. The correlation between the NPF event frequency and the particle formation and growth rate was at best moderate between the different measurement sites, as well as between the sites belonging to a certain environmental regime. For a better understanding of atmospheric NPF and its regional importance, we would need more observational data from different urban areas in practically all parts of the world, from additional remote and rural locations in Northern America, Asia and most of the Southern Hemisphere (especially Australia), from polar areas, and from at least a few locations over the oceans.

scholarly journals Observation of aerosol size distribution and new particle formation at a mountain site in subtropical Hong Kong

2012 ◽  
Vol 12 (20) ◽  
pp. 9923-9939 ◽  
Author(s):  
H. Guo ◽  
D. W. Wang ◽  
K. Cheung ◽  
Z. H. Ling ◽  
C. K. Chan ◽  
...  
Keyword(s):  
Growth Rate ◽  
Hong Kong ◽  
Sulfuric Acid ◽  
Size Distribution ◽  
Formation Rate ◽  
Particle Formation ◽  
Aerosol Size Distribution ◽  
New Particle Formation ◽  
Average Growth ◽  
Nucleation Mode

Abstract. In order to investigate the formation and growth processes of nucleation mode particles, and to quantify the particle number (PN) concentration and size distributions in Hong Kong, an intensive field measurement was conducted from 25 October to 29 November in 2010 near the mountain summit of Tai Mo Shan, a suburban site approximately the geographical centre of the New Territories in Hong Kong. Based on observations of the particle size distribution, new particle formation (NPF) events were found on 12 out of 35 days with the estimated formation rate J5.5 from 0.97 to 10.2 cm−3 s−1, and the average growth rates from 1.5 to 8.4 nm h−1. The events usually began at 10:00–11:00 LT characterized by the occurrence of a nucleation mode with a peak diameter of 6–10 nm. Solar radiation, wind speed, sulfur dioxide (SO2) and ozone (O3) concentrations were on average higher, whereas temperature, relative humidity and daytime nitrogen dioxide (NO2) concentration were lower on NPF days than on non-NPF days. Back trajectory analysis suggested that in majority of the NPF event days, the air masses originated from the northwest to northeast directions. The concentrations of gaseous sulfuric acid (SA) showed good power-law relationship with formation rates, with exponents ranging from 1 to 2. The result suggests that the cluster activation theory and kinetic nucleation could potentially explain the observed NPF events in this mountainous atmosphere of Hong Kong. Meanwhile, in these NPF events, the contribution of sulfuric acid vapor to particle growth rate (GR5.5–25) ranged from 9.2 to 52.5% with an average of 26%. Measurement-based calculated oxidation rates of monoterpenes (i.e. α-pinene, β-pinene, myrcene and limonene) by O3 positively correlated with the GR5.5–25 (R = 0.80, p < 0.05). The observed associations of the estimated formation rate J5.5 and the growth rate GR5.5–25 with gaseous sulfuric acid and volatile organic compounds (VOCs) suggested the critical roles of sulfuric acid and biogenic VOCs (e.g. α-pinene and β-pinene) in these NPF events.

scholarly journals New particle formation in the western Yangtze River Delta: first data from SORPES-station

2013 ◽  
Vol 13 (1) ◽  
pp. 1455-1488 ◽  
Author(s):  
E. Herrmann ◽  
A. J. Ding ◽  
T. Petäjä ◽  
X. Q. Yang ◽  
J. N. Sun ◽  
...  
Keyword(s):  
Yangtze River ◽  
Meteorological Data ◽  
Formation Rate ◽  
Yangtze River Delta ◽  
Particle Formation ◽  
River Delta ◽  
New Particle Formation ◽  
Total Particle ◽  
The Mean ◽  
The Yrd

Abstract. Aerosols and new particle formation were studied in the western part of the Yangtze River Delta (YRD), at the SORPES station of Nanjing University. Air ions between 0.8 and 42 nm were measured using an air ion spectrometer; a DMPS provided particle size distributions between 6 and 800 nm. Additionally, meteorological data, trace gas concentrations, and PM2.5 values were recorded. During the measurement period from 18 November 2011 to 31 March 2012, the mean total particle concentration was found to be 23 000 cm−3. The mean PM2.5 value was 90 μ g m−3, well above national limits. During the observations, 26 new particle formation events occurred, typically producing 6 nm particles at a rate of 1 cm−3 s−1, resulting in over 4000 cm−3 new CCN per event. Typical growth rates were between 6 and 7 nm h−1. Ion measurements showed the typical cluster band below 2 nm, with total ion concentrations roughly between 600 and 1000 cm−3. A peculiar feature of the ion measurements were the heightened ion cluster concentrations during the nights before event days. The highly polluted air of the YRD provides both the potential source (SO2) and the sink (particulate matter) for sulfuric acid, leaving radiation as the determining force behind new particle formation. Accordingly, a good correlation was found between new particle formation rate and radiation values.

scholarly journals Characterization of ultrafine particle number concentration and new particle formation in urban environment of Taipei, Taiwan

2013 ◽  
Vol 13 (4) ◽  
pp. 8985-9016 ◽  
Author(s):  
H. C. Cheung ◽  
C. C.-K. Chou ◽  
W.-R. Huang ◽  
C.-Y. Tsai
Keyword(s):  
Growth Rate ◽  
Urban Areas ◽  
Formation Rate ◽  
Particle Formation ◽  
Number Concentration ◽  
New Particle Formation ◽  
Urban Background ◽  
Photo Oxidation ◽  
Nucleation Mode ◽  
Quadratic Relationship

Abstract. An intensive aerosol characterization experiment was performed at the Taipei Aerosol and Radiation Observatory (TARO, 25.02° N, 121.53° E) in the urban area of Taipei, Taiwan during July 2012. Number concentration and size distribution of aerosol particles were measured continuously, which were accompanied by concurrent measurements of mass concentration of submicron particles, PM (d ≤ 1 μm), and photolysis rate of ozone, J(O1D). The averaged number concentrations of total (Ntotal), accumulation mode (Nacu), Aitken mode (Ntotal), and nucleation mode (Nnuc) particles were 7.6 × 103 cm−3, 1.2 × 103 cm−3, 4.4 × 103 cm−3, and 1.9 × 103 cm−3, respectively. Accordingly, the ultrafine particles (UFPs, d ≤ 100 nm) accounted for 83% of the total number concentration of particles measured in this study (10 ≤ d ≤ 429 nm), indicating the importance of UFPs to the air quality and radiation budget in Taipei and its surrounding areas. An averaged Nnuc/NOx ratio of ~60 cm−3 ppbv−1 was derived from nighttime measurements, which was suggested to be the characteristic of vehicle emissions that contributed to the "urban background" of nucleation mode particles throughout a day. On the contrary, it was found that the number concentration of nucleation mode particles was independent of NOx and could be elevated up to 10 times the "urban background" levels during daytime, suggesting a substantial amount of nucleation mode particles produced from photochemical processes. Consistency in the time series of the nucleation mode particle concentration and the proxy of H2SO4 production, UVB·SO2, for new particle formation (NPF) events showed that photo-oxidation of SO2 was responsible for the formation of new particles in our study area. Moreover, analysis upon the diameter growth rate, GR, and formation rate of nucleation mode particles, J10−25, found that the values of GR (8.5 ± 6.8 nm h−1) in Taipei were comparable to other urban areas, whereas the values of J10−25 (2.2 ± 1.2 cm−3 s−1) observed in this study were around the low end of the range of new particle formation rate reported by previous investigations. It was revealed that the particle growth rate correlated exponentially with the photolysis of ozone, suggesting the condensable vapors were produced mostly from photo-oxidation reactions. In addition, this study also revealed that both GR and J10−25 exhibited quadratic relationship with the number concentration of particles. The quadratic relationship was inferred as a result of aerosol dynamics and featured NPF process in urban areas.

scholarly journals Atmospheric new particle formation characteristics in the Arctic as measured at Mount Zeppelin, Svalbard, from 2016 to 2018

2020 ◽  
Author(s):  
Haebum Lee ◽  
KwangYul Lee ◽  
Chris Rene Lunder ◽  
Radovan Krejci ◽  
Wenche Aas ◽  
...  
Keyword(s):  
Growth Rate ◽  
Dimethyl Sulfide ◽  
Formation Rate ◽  
Production Capacity ◽  
Particle Formation ◽  
The Arctic ◽  
Average Particle ◽  
New Particle Formation ◽  
Low Loss ◽  
Average Growth

Abstract. We conducted continuous measurement of nanoparticles down to 3 nm size in the Arctic at Mount Zeppelin, Ny Ålesund, Svalbard, from 2016 to 2018, providing a size distribution of nanoparticles (3–60 nm) with a higher resolution than ever before. A significant number of nanoparticles as small as 3 nm were often observed during new particle formation (NPF), particularly in summer, suggesting that these were likely produced near the site rather than being transported from other regions after growth. The average NPF frequency per year was 24 % having the highest percentage in August (63 %). The average particle formation rate (J) for 3–7 nm particles was 0.1 cm−3 s−1 and the average growth rate (GR) was 2.62 nm h−1. Although NPF frequency in the Arctic was comparable to that in continental areas, the J and GR were much lower. The number of nanoparticles increased more frequently when air mass originated over the south and southwest ocean regions; this pattern overlapped with regions having strong chlorophyll-α concentration and dimethyl sulfide (DMS) production capacity (southwest ocean), and was also correlated with increased daily NH3 concentration, suggesting that marine biogenic and animal sources were responsible for gaseous precursors to NPF. Our results show that previously developed NPF occurrence criteria (low loss rate and high cluster growth rate favor NPF) are also applicable to NPF in the Arctic.

scholarly journals Changes in the production rate of secondary aerosol particles in Central Europe in view of decreasing SO<sub>2</sub> emissions between 1996 and 2006

2010 ◽  
Vol 10 (3) ◽  
pp. 1071-1091 ◽  
Author(s):  
A. Hamed ◽  
W. Birmili ◽  
J. Joutsensaari ◽  
S. Mikkonen ◽  
A. Asmi ◽  
...  
Keyword(s):  
Growth Rate ◽  
Cloud Condensation Nuclei ◽  
Formation Rate ◽  
Global Radiation ◽  
Particle Diameter ◽  
Particle Formation ◽  
Research Station ◽  
Particle Nucleation ◽  
New Particle Formation ◽  
New Particles

Abstract. In anthropogenically influenced atmospheres, sulphur dioxide (SO2) is the main precursor of gaseous sulphuric acid (H2SO4), which in turn is a main precursor for atmospheric particle nucleation. As a result of socio-economic changes, East Germany has seen a dramatic decrease in anthropogenic SO2 emissions between 1989 and present, as documented by routine air quality measurements in many locations. We have attempted to evaluate the influence of changing SO2 concentrations on the frequency and intensity of new particle formation (NPF) using two different data sets (1996–1997; 2003–2006) of experimental particle number size distributions (diameter range 3–750 nm) from the atmospheric research station Melpitz near Leipzig, Germany. Between the two periods SO2 concentrations decreased by 65% on average, while the frequency of NPF events dropped by 45%. Meanwhile, the average formation rate of 3 nm particles decreased by 68% on average. The trends were statistically significant and therefore suggest a connection between the availability of anthropogenic SO2 and freshly formed new particles. In contrast to the decrease in new particle formation, we found an increase in the mean growth rate of freshly nucleated particles (+22%), suggesting that particle nucleation and subsequent growth into larger sizes are delineated with respect to their precursor species. Using three basic parameters, the condensation sink for H2SO4, the SO2 concentration, and the global radiation intensity, we were able to define the characteristic range of atmospheric conditions under which particle formation events take place at the Melpitz site. While the decrease in the concentrations and formation rates of the new particles was rather evident, no similar decrease was found with respect to the generation of cloud condensation nuclei (CCN; particle diameter >100 nm) as a result of atmospheric nucleation events. On the contrary, the production of CCN following nucleation events appears to have increased by tens of percents. Our aerosol dynamics model simulations suggest that such an increase can be caused by the increased particle growth rate.

scholarly journals Atmospheric new particle formation in China

2019 ◽  
Vol 19 (1) ◽  
pp. 115-138 ◽  
Author(s):  
Biwu Chu ◽  
Veli-Matti Kerminen ◽  
Federico Bianchi ◽  
Chao Yan ◽  
Tuukka Petäjä ◽  
...  
Keyword(s):  
Air Pollution ◽  
Growth Rate ◽  
Formation Rate ◽  
Particle Growth ◽  
Particle Formation ◽  
New Particle Formation ◽  
Growth Mechanisms ◽  
Different Types ◽  
Different Seasons ◽  
Heavy Pollution

Abstract. New particle formation (NPF) studies in China were summarized comprehensively in this paper. NPF frequency, formation rate, and particle growth rate were closely compared among the observations carried out at different types of sites in different regions of China in different seasons, with the aim of exploring the nucleation and particle growth mechanisms. The interactions between air pollution and NPF are discussed, emphasizing the properties of NPF under heavy pollution conditions. The current understanding of NPF cannot fully explain the frequent occurrence of NPF at high aerosol loadings in China, and possible reasons for this phenomenon are proposed. The effects of NPF and some aspects of NPF research requiring further investigation are also summarized in this paper.

scholarly journals Investigation of new particle formation at the summit of Mt. Tai, China

2016 ◽  
Author(s):  
Ganglin Lv ◽  
Xiao Sui ◽  
Jianmin Chen ◽  
Rohan Jayaratne ◽  
Abdelwahid Mellouki
Keyword(s):  
Growth Rate ◽  
Sulfuric Acid ◽  
Sulfur Dioxide ◽  
Growth Rates ◽  
Formation Rate ◽  
High Elevation ◽  
Particle Formation ◽  
Mean Value ◽  
New Particle Formation ◽  
Total Particle

Abstract. To date very few field observations of new particle formation (NPF) have been carried out at the high-elevation mountain sites in China. Simultaneously measurements of particle size distributions, gas species, meteorological conditions and PM2.5 were performed at the summit of Mt. Tai (1530 m ASL) from 25 July to 24 October 2014 (І), 21 September to 9 December 2014 (И) and 16 June to 7 August 2015 (Ш). The results showed that: (i) 66 NPF events were observed during 164 days, corresponding to an occurrence frequency of 40 %. Formation rates, growth rates and condensation sinks were in the range of 1.10–57.43 cm−3 s−1, 0.58–7.76 nm h−1 and 0.40 × 10−2–6.32 × 10−2 s−1, respectively, and Mt. Tai appeared to show the larger formation rate and smaller growth rate relative to other locations in China. The mean value of sulfur dioxide on NPF days was 46 % higher than that on non-NPF days, and a higher sulfur dioxide concentration could improve the possibility of rich precursors for NPF. (ii) Sulfuric acid condensation contributed to 16.20 % of growth rate, and sulfuric acid proxy showed an obvious correlation with total particle concentration of 3–6 nm (N3–6 nm). (iii) Low PM2.5 was favourable for nucleation, and NPF days with limited higher PM2.5 seemed to have larger growth rates which might be related to particles recombination in close sizes. Four NPF events were observed on haze episodes, which could be promoted by potential specific mechanisms or pollutants. (iv) Particles formed via NPF on both clean and polluted days mainly contributed to Aiken mode eventually, and PM2.5 variation was always in accordance with particle total volume concentration.

scholarly journals New particle formation events in semi-clean South African savannah

2011 ◽  
Vol 11 (7) ◽  
pp. 3333-3346 ◽  
Author(s):  
V. Vakkari ◽  
H. Laakso ◽  
M. Kulmala ◽  
A. Laaksonen ◽  
D. Mabaso ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Growth Rate ◽  
Particle Size ◽  
Sulphuric Acid ◽  
Growth Rates ◽  
Formation Rate ◽  
Particle Formation ◽  
Size Distributions ◽  
New Particle Formation ◽  
Particle Formation And Growth

Abstract. This study is based on 18 months (20 July 2006–5 February 2008) of continuous measurements of aerosol particle size distributions, air ion size distributions, trace gas concentrations and basic meteorology in a semi-clean savannah environment in Republic of South Africa. New particle formation and growth was observed on 69% of the days and bursts of non-growing ions/sub-10 nm particles on additional 14% of the days. This new particle formation frequency is the highest reported from boundary layer so far. Also the new particle formation and growth rates were among the highest reported in the literature for continental boundary layer locations; median 10 nm formation rate was 2.2 cm−3 s−1 and median 10–30 nm growth rate 8.9 nm h−1. The median 2 nm ion formation rate was 0.5 cm−3 s−1 and the median ion growth rates were 6.2, 8.0 and 8.1 nm h−1 for size ranges 1.5–3 nm, 3–7 nm and 7–20 nm, respectively. The growth rates had a clear seasonal dependency with minimum during winter and maxima in spring and late summer. The relative contribution of estimated sulphuric acid to the growth rate was decreasing with increasing particle size and could explain more than 20% of the observed growth rate only for the 1.5–3 nm size range. Also the air mass history analysis indicated the highest formation and growth rates to be associated with the area of highest VOC (Volatile Organic Compounds) emissions following from biological activity rather than the highest estimated sulphuric acid concentrations. The frequency of new particle formation, however, increased nearly monotonously with the estimated sulphuric acid reaching 100% at H2SO4 concentration of 6 · 107 cm−3, which suggests the formation and growth to be independent of each other.

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