气候变化领域集成服务门户(CCPortal): New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula

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DOI	10.5194/acp-20-14253-2020
	New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula
	Casquero-Vera J.A.; Lyamani H.; Dada L.; Hakala S.; Paasonen P.; Román R.; Fraile R.; Petäjä T.; Olmo-Reyes F.J.; Alados-Arboledas L.
发表日期	2020
ISSN	16807316
起始页码	14253
结束页码	14271
卷号	20 期号:22
英文摘要	A substantial fraction of the atmospheric aerosols originates from secondary new particle formation (NPF), where atmospheric vapours are transformed into particles that subsequently grow to larger sizes, affecting human health and the climate. In this study, we investigate aerosol size distributions at two stations located close to each other (∼20 km) but at different altitudes: Urban (UGR; 680ma.s.l., metres above sea level) and high-altitude remote (SNS; 2500ma.s.l.) sites, both in the area of Granada, Spain, and part of AGORA observatory (Andalusian Global ObseRvatory of the Atmosphere). The analysis shows a significant contribution of nucleation mode aerosol particles to the total aerosol number concentration at both sites, with a contribution of 47% and 48% at SNS and UGR, respectively. Due to the important contribution of NPF events to the total aerosol number concentrations and their high occurrence frequency (>70 %) during the study period, a detailed analysis of NPF events is done in order to get insight into the possible mechanisms and processes involved in NPF events at these contrastive sites. At SNS, NPF is found to be associated with the transport of gaseous precursors from lower altitudes by orographic buoyant upward flows. NPF events at the SNS site are always observed from the smallest measured sizes of the aerosol size distribution (4 nm), implying that NPF takes place in or in the vicinity of the high-altitude SNS station rather than being transported from lower altitudes. Although NPF events at the mountain site seem to be connected with those occurring at the urban site, growth rates (GRs) at SNS are higher than those at the UGR site (GR7-25 of 6.9 and 4.5 nm h-1 and GR4-7 of 4.1 and 3.6 nm h-1 at SNS and UGR, respectively). This fact could have special importance for the production of cloud condensation nuclei (CCN) and therefore for cloud formations which may affect regional/global climate, since larger GRs at mountain sites could translate to a larger survival probability of NPF particles reaching CCN sizes, due to the shorter time period needed for the growth. The analysis of sulfuric acid (H2SO4) shows that the contribution of H2SO4 is able to explain a minimal fraction contribution to the observed GRs at both sites (<1%and <10%for the 7-25 and 4-7 nm size ranges, respectively), indicating that other condensing vapours are responsible for the majority of particle growth, as well as the differing growth rates between the two sites. Results also show that the condensation sink (CS) does not play a relevant role in NPF processes at both sites and points to the availability of volatile organic compounds (VOCs) as one of the main factors controlling the NPF events at both sites. Finally, a closer analysis of the NPF events that were observed at the SNS site during a Saharan dust episode that occurred during the field campaign was carried out, evidencing the role of TiO2 and F2O3 together with VOCs in promoting new particle formation during this dust intrusion event. Although further investigation is needed to improve our understanding in this topic, this result suggests that climate effects of mineral dust and NPF are not disconnected from each other as it was commonly thought. Therefore, since mineral dust contributes to a major fraction of the global aerosol mass load, dust-NPF interaction should be taken into account in global aerosol-climate modelling for better climate change prediction. © Author(s) 2020.
语种	英语
scopus关键词	aerosol formation; altitude; mineral dust; nucleation; particle size; urban area; water vapor; Andalucia; Granada [Andalucia]; Iberian Peninsula; Spain
来源期刊	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/152795
作者单位	Andalusian Institute for Earth System Research (IISTA-CEAMA), University of Granada, Autonomous Government of Andalusia, Granada, Spain; Department of Applied Physics, University of Granada, Granada, Spain; Institute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland; Grupo de Óptica Atmosférica (GOA), Universidad de Valladolid, Valladolid, Spain; Department of Physics, University of Leon, Leon, Spain
推荐引用方式 GB/T 7714	Casquero-Vera J.A.,Lyamani H.,Dada L.,et al. New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula[J],2020,20(22).
APA	Casquero-Vera J.A..,Lyamani H..,Dada L..,Hakala S..,Paasonen P..,...&Alados-Arboledas L..(2020).New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula.Atmospheric Chemistry and Physics,20(22).
MLA	Casquero-Vera J.A.,et al."New particle formation at urban and high-altitude remote sites in the south-eastern Iberian Peninsula".Atmospheric Chemistry and Physics 20.22(2020).