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Rapid growth of new atmospheric particles by nitric acid and ammonia condensation 期刊论文
NATURE, 2020, 581 (7807) : 184-+
作者:  Liang, Guanxiang;  Zhao, Chunyu;  Zhang, Huanjia;  Mattei, Lisa;  Sherrill-Mix, Scott;  Bittinger, Kyle;  Kessler, Lyanna R.;  Wu, Gary D.;  Baldassano, Robert N.;  DeRusso, Patricia;  Ford, Eileen;  Elovitz, Michal A.;  Kelly, Matthew S.;  Patel, Mohamed Z.;  Mazhani, Tiny;  Gerber, Jeffrey S.;  Kelly, Andrea;  Zemel, Babette S.;  Bushman, Frederic D.
收藏  |  浏览/下载:17/0  |  提交时间:2020/05/20

A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog(1,2), but how it occurs in cities is often puzzling(3). If the growth rates of urban particles are similar to those found in cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below -15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acid-base stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms(4,5).


  
Premature mortality related to United States cross-state air pollution 期刊论文
NATURE, 2020, 578 (7794) : 261-+
作者:  Helmink, Beth A.;  Reddy, Sangeetha M.;  Gao, Jianjun;  Zhang, Shaojun;  Basar, Rafet;  Thakur, Rohit;  Yizhak, Keren;  Sade-Feldman, Moshe;  Blando, Jorge;  Han, Guangchun;  Gopalakrishnan, Vancheswaran;  Xi, Yuanxin;  Zhao, Hao;  Amaria, Rodabe N.;  Tawbi, Hussein A.;  Cogdill, Alex P.;  Liu, Wenbin;  LeBleu, Valerie S.;  Kugeratski, Fernanda G.;  Patel, Sapna;  Davies, Michael A.;  Hwu, Patrick;  Lee, Jeffrey E.;  Gershenwald, Jeffrey E.;  Lucci, Anthony;  Arora, Reetakshi;  Woodman, Scott;  Keung, Emily Z.;  Gaudreau, Pierre-Olivier;  Reuben, Alexandre;  Spencer, Christine N.;  Burton, Elizabeth M.;  Haydu, Lauren E.;  Lazar, Alexander J.;  Zapassodi, Roberta;  Hudgens, Courtney W.;  Ledesma, Deborah A.;  Ong, SuFey;  Bailey, Michael;  Warren, Sarah;  Rao, Disha;  Krijgsman, Oscar;  Rozeman, Elisa A.;  Peeper, Daniel;  Blank, Christian U.;  Schumacher, Ton N.;  Butterfield, Lisa H.;  Zelazowska, Monika A.;  McBride, Kevin M.;  Kalluri, Raghu;  Allison, James;  Petitprez, Florent;  Fridman, Wolf Herman;  Sautes-Fridman, Catherine;  Hacohen, Nir;  Rezvani, Katayoun;  Sharma, Padmanee;  Tetzlaff, Michael T.;  Wang, Linghua;  Wargo, Jennifer A.
收藏  |  浏览/下载:37/0  |  提交时间:2020/05/13

Outdoor air pollution adversely affects human health and is estimated to be responsible for five to ten per cent of the total annual premature mortality in the contiguous United States(1-3). Combustion emissions from a variety of sources, such as power generation or road traffic, make a large contribution to harmful air pollutants such as ozone and fine particulate matter (PM2.5)(4). Efforts to mitigate air pollution have focused mainly on the relationship between local emission sources and local air quality(2). Air quality can also be affected by distant emission sources, however, including emissions from neighbouring federal states(5,6). This cross-state exchange of pollution poses additional regulatory challenges. Here we quantify the exchange of air pollution among the contiguous United States, and assess its impact on premature mortality that is linked to increased human exposure to PM2.5 and ozone from seven emission sectors for 2005 to 2018. On average, we find that 41 to 53 per cent of air-quality-related premature mortality resulting from a state'  s emissions occurs outside that state. We also find variations in the cross-state contributions of different emission sectors and chemical species to premature mortality, and changes in these variations over time. Emissions from electric power generation have the greatest cross-state impacts as a fraction of their total impacts, whereas commercial/residential emissions have the smallest. However, reductions in emissions from electric power generation since 2005 have meant that, by 2018, cross-state premature mortality associated with the commercial/residential sector was twice that associated with power generation. In terms of the chemical species emitted, nitrogen oxides and sulfur dioxide emissions caused the most cross-state premature deaths in 2005, but by 2018 primary PM2.5 emissions led to cross-state premature deaths equal to three times those associated with sulfur dioxide emissions. These reported shifts in emission sectors and emission species that contribute to premature mortality may help to guide improvements to air quality in the contiguous United States.


  
Effects of highways on bird distribution and soundscape diversity around Aldo Leopold's shack in Baraboo, Wisconsin, USA 期刊论文
LANDSCAPE AND URBAN PLANNING, 2019, 192
作者:  Khanaposhtani, Maryam Ghadiri;  Gasc, Amandine;  Francomano, Dante;  Villanueva-Rivera, Luis J.;  Jung, Jinha;  Mossman, Michael J.;  Pijanowski, Bryan C.
收藏  |  浏览/下载:13/0  |  提交时间:2020/02/17
Bird community  Traffic noise  Road effect  Soundscape  LiDAR  Habitat structure  
Active stakeholder involvement and organisational tasks as factors for an effective communication and governance strategy in the promotion of e-taxis. Results from a field research lab 期刊论文
ENERGY POLICY, 2019, 135
作者:  Goldschmidt, Ruediger;  Richter, Andreas;  Pfeil, Raphael
收藏  |  浏览/下载:9/0  |  提交时间:2020/02/17
Traffic electrification  E-Taxi  Communication strategy  Governance strategy  Stakeholder involvement  EV  
Influence of skidder traffic on soil bulk density, aspen regeneration, and vegetation indices following winter harvesting in the Duck Mountain Provincial Park, SK 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2019, 437: 59-69
作者:  Sealey, Landon L.;  Van Rees, Ken C. J.
收藏  |  浏览/下载:5/0  |  提交时间:2019/04/09
Soil bulk density  Unoccupied aerial vehicles  UAV  Trembling aspen  Populus tremuloides  Winter harvesting  Soil compaction  Traffic intensity  Aspen regeneration  Multispectral remote sensing  
Characterization of PM2.5-bound nitrated and oxygenated polycyclic aromatic hydrocarbons in ambient air of Langfang during periods with and without traffic restriction 期刊论文
ATMOSPHERIC RESEARCH, 2018, 213: 302-308
作者:  Zhao, Jingbo;  Zhang, Jing;  Sun, Luna;  Liu, Yan;  Lin, Yingchao;  Li, Yuening;  Wang, Ting;  Mao, Hongjun
收藏  |  浏览/下载:6/0  |  提交时间:2019/04/09
nPAHs  oPAHs  PM2.5  Diurnal variation  Traffic restriction  
Sources and physicochemical characteristics of submicron aerosols during three intensive campaigns in Granada (Spain) 期刊论文
ATMOSPHERIC RESEARCH, 2018, 213: 398-410
作者:  del Aguila, A.;  Sorribas, M.;  Lyamani, H.;  Titos, G.;  Olmo, F. J.;  Arruda-Moreira, G.;  Yela, M.;  Alados-Arboledas, L.
收藏  |  浏览/下载:10/0  |  提交时间:2019/04/09
Submicron size distribution  Chemical composition  Source apportionment  New particle formation  Biomass burning  Traffic contribution  
Transport policies, induced traffic and their influence on vehicle emissions in developed and developing countries 期刊论文
ENERGY POLICY, 2018, 121: 264-274
作者:  Lee, Shin
收藏  |  浏览/下载:4/0  |  提交时间:2019/04/09
Vehicle emission reductions  Road capacity expansion  Travel demand management  Induced traffic  Policy effectiveness  Developed and developing countries  
Bicycle, pedestrian, and mixed-mode trail traffic: A performance assessment of demand models 期刊论文
LANDSCAPE AND URBAN PLANNING, 2018, 177: 92-102
作者:  Ermagun, Alireza;  Lindsey, Greg;  Loh, Tracy Hadden
收藏  |  浏览/下载:3/0  |  提交时间:2019/04/09
Trail traffic  Average daily bicyclists  Average daily pedestrians  Mixed-mode  Demand model  Built environment  
Elk responses to trail-based recreation on public forests 期刊论文
FOREST ECOLOGY AND MANAGEMENT, 2018, 411: 223-233
作者:  Wisdom, Michael J.;  Preisler, Haiganoush K.;  Naylor, Leslie M.;  Anthony, Robert G.;  Johnson, Bruce K.;  Rowland, Mary M.
收藏  |  浏览/下载:8/0  |  提交时间:2019/04/09
All-terrain vehicles  ATV riding  Elk  Forest roads  Hiking  Horseback riding  Mountain biking  Motorized traffic  Off-highway vehicles  Public forests  Recreation  Recreation trails  Road avoidance  Roads