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·高被引論文摘要·

2017-01-26 14:05:50

·高被引論文摘要·

被引頻次:304

中國(guó)城市光化學(xué)煙霧污染研究

張遠(yuǎn)航,邵可聲,唐孝炎,等

根據(jù)在蘭州西固石油化工區(qū)、北京燕山石油化工區(qū)、北京地區(qū)和廣州地區(qū)開展的光化學(xué)煙霧研究,討論我國(guó)城市光化學(xué)煙霧的污染狀況及其污染特征,探討光化學(xué)煙霧的形成機(jī)制,并預(yù)測(cè)城市光化學(xué)煙霧的發(fā)展趨勢(shì)。結(jié)果表明,上述地區(qū)存在嚴(yán)重的光化學(xué)煙霧污染,控制我國(guó)光化學(xué)煙霧污染的有效途徑是降低NOx排放;北京中關(guān)村大氣 O3最大小時(shí)濃度不僅逐年遞增,而且出現(xiàn) O3最大值的時(shí)間也提前,說(shuō)明大氣光化學(xué)活性增強(qiáng);隨著機(jī)動(dòng)車保有量的迅猛增加,一些大城市的大氣污染已逐漸由煤煙型轉(zhuǎn)向機(jī)動(dòng)車尾氣污染型,或成為具有二者綜合的污染特征。

光化學(xué)煙霧;臭氧;空氣質(zhì)量

來(lái)源出版物:北京大學(xué)學(xué)報(bào):自然科學(xué)版, 1998, 34(2-3): 392-400

被引頻次:242

我國(guó)城市地區(qū)機(jī)動(dòng)車污染現(xiàn)狀與趨勢(shì)

謝紹東,張遠(yuǎn)航,唐孝炎

摘要:北京、廣州和上海近 10多年機(jī)動(dòng)車保有量年均增長(zhǎng)速率分別為 164%,165%和 134%,這些城市大約80%的CO和40%的NOx來(lái)自于機(jī)動(dòng)車排放。其結(jié)果是導(dǎo)致城區(qū)大氣環(huán)境近10 a來(lái)NOx濃度逐年上升,已成為廣州和北京等少數(shù)特大城市的首要污染物;街道大氣環(huán)境中NOx和CO日均濃度遠(yuǎn)遠(yuǎn)超過(guò)國(guó)家大氣環(huán)境質(zhì)量二級(jí)標(biāo)準(zhǔn),其污染程度比城區(qū)整體環(huán)境更為嚴(yán)重;已存在嚴(yán)重的光化學(xué)煙霧污染,預(yù)測(cè)表明城區(qū)未來(lái)大氣環(huán)境中O3濃度的高低取決于機(jī)動(dòng)車的排放量。因此,我國(guó)城市地區(qū)大氣污染正由煤煙型污染向機(jī)動(dòng)車尾氣污染轉(zhuǎn)化。關(guān)鍵詞:機(jī)動(dòng)車排氣污染;光化學(xué)煙霧;機(jī)動(dòng)車保有量;城市地區(qū)

來(lái)源出版物:環(huán)境科學(xué)研究, 2000, 13(4): 22-38

被引頻次:178

灰霾天氣的形成與演化

吳兌

摘要:由于經(jīng)濟(jì)規(guī)模迅速擴(kuò)大和城市化進(jìn)程加快,大氣氣溶膠污染日趨嚴(yán)重,由氣溶膠造成的能見(jiàn)度惡化事件越來(lái)越多,這些人類活動(dòng)排放的污染物,包括直接排放的氣溶膠和氣態(tài)污染物通過(guò)化學(xué)轉(zhuǎn)化與光化學(xué)轉(zhuǎn)化形成的細(xì)粒子二次氣溶膠,可形成灰霾(特指人類活動(dòng)源排放的大氣污染物誘發(fā)的低能見(jiàn)度事件),致使能見(jiàn)度下降。我國(guó)東部地區(qū)灰霾天氣迅速增加,灰霾天氣的本質(zhì)是細(xì)粒子氣溶膠污染,與光化學(xué)煙霧相關(guān)聯(lián),形成灰霾天氣的氣溶膠組成非常復(fù)雜。近年來(lái)由于灰霾天氣日趨嚴(yán)重引發(fā)的環(huán)境效應(yīng)問(wèn)題和氣溶膠輻射強(qiáng)迫引發(fā)的氣候效應(yīng)問(wèn)題,廣泛地引起科學(xué)界、政府部門和社會(huì)公眾的關(guān)注,而成為熱門話題。文章討論了目前對(duì)灰霾天氣的認(rèn)識(shí),灰霾的定義與判別標(biāo)準(zhǔn),灰霾天氣與光化學(xué)煙霧、氣象條件的關(guān)系,也涉及灰霾天氣對(duì)人體健康的影響。展望了灰霾研究的前景與主要研究方向和內(nèi)容。

關(guān)鍵詞:灰霾天氣;形成與演化;細(xì)粒子污染;灰霾定義;灰霾標(biāo)準(zhǔn)

來(lái)源出版物:環(huán)境科學(xué)與技術(shù), 2011, 34(3): 157-161

被引頻次:173

我國(guó)汽車排氣污染現(xiàn)狀與發(fā)展

范秀英,張微,韓圣慧

摘要:從汽車保有量、油品消耗、污染物排放和重點(diǎn)城市大氣環(huán)境質(zhì)量等方面分析了我國(guó)汽車污染現(xiàn)狀及2000年和2010年2個(gè)時(shí)段的發(fā)展趨勢(shì),從節(jié)能、凈化和管理的角度初步分析了削減汽車污染物排放的綜合對(duì)策。

關(guān)鍵詞:汽車保有量;汽車污染;污染分擔(dān)率

來(lái)源出版物:環(huán)境科學(xué), 1996, 17(4): 80-96

被引頻次:151

北京大氣中NO、NO2和O3濃度變化的相關(guān)性分析

安俊琳,王躍思,李昕

摘要:臭氧(O3)是城市污染大氣中的首要光化學(xué)污染物,其變化規(guī)律與氮氧化物(NOx=NO+NO2)關(guān)系密切。采用49C臭氧分析儀和42CTL氮氧化物分析儀對(duì)北京城區(qū)O3和NOx濃度進(jìn)行了連續(xù)觀測(cè),時(shí)間為2004-08—2005-07。結(jié)果顯示,O3和Ox(O3+NO2)濃度在午后15 : 00左右出現(xiàn)峰值,NOx呈雙峰態(tài)日變化,在07 : 00 和23 : 00左右出現(xiàn)峰值。不同季節(jié)污染物的濃度變化存在差異,O3和NOx濃度分別在夏季和冬季達(dá)到最大。NOx濃度存在 100×10-9(體積分?jǐn)?shù))的“分界點(diǎn)”,NOx低濃度時(shí)以NO2為主,NOx高濃度時(shí)NO占大部分。OX區(qū)域貢獻(xiàn)和局地貢獻(xiàn)存在明顯的季節(jié)變化,前者主要受區(qū)域背景O3的影響,在春季最大,后者主要受局地NOx光化學(xué)反應(yīng)的制約,在夏季最強(qiáng),同時(shí)OX組分呈現(xiàn)顯著的晝夜差異。

關(guān)鍵詞:城市大氣污染;光化學(xué)氧化劑;臭氧;區(qū)域貢獻(xiàn);局地貢獻(xiàn)

來(lái)源出版物:環(huán)境科學(xué), 2007, 28(4): 706-711

被引頻次:96

北京地區(qū)嚴(yán)重大氣污染的氣象和化學(xué)因子

劉小紅,洪鐘祥,李家倫,等

摘要:利用北京325 m氣象塔進(jìn)行了大氣污染物O3、NOx、CO和氣象要素的同步觀測(cè),對(duì)影響大氣污染的氣象和化學(xué)因子進(jìn)行了分析,探討大氣污染物變化的規(guī)律,為城市空氣污染預(yù)報(bào)提供理論基礎(chǔ)。

關(guān)鍵詞:長(zhǎng)江口;表層沉積物;重金屬;環(huán)境評(píng)價(jià)

來(lái)源出版物:環(huán)境科學(xué), 2008, 29(9): 2405-2412

被引頻次:89

城市臭氧濃度分布特征

殷永泉,李昌梅,馬桂霞,等

摘要:近地面層臭氧(O3)研究是當(dāng)今環(huán)境科學(xué)領(lǐng)域的前沿課題之一,隨著汽車尾氣排放 NOx和碳?xì)浠衔锏脑黾?,在日光照射等條件下導(dǎo)致低層大氣中 O3濃度明顯增高,面臨光化學(xué)煙霧污染的威脅,開展環(huán)境空氣中O3監(jiān)測(cè)與分析對(duì)防治大氣污染有十分重要的意義。利用2003年6個(gè)月的臭氧(O3)自動(dòng)連續(xù)監(jiān)測(cè)數(shù)據(jù),對(duì)山東大學(xué)校園內(nèi) O3濃度的頻率分布、日變化、月變化等特征進(jìn)行分析。實(shí)驗(yàn)結(jié)果表明,O3小時(shí)平均濃度達(dá)到《環(huán)境空氣質(zhì)量標(biāo)準(zhǔn)》(GB 3095—1996)二級(jí)標(biāo)準(zhǔn)的頻率為96.88%;O3濃度呈明顯的日變化,一般在下午濃度較高,上午和夜晚較低;O3濃度的最高值出現(xiàn)在6月份,這與輻射強(qiáng)烈,溫度高有關(guān);天氣條件也影響O3濃度,一般晴天時(shí)O3濃度高,多云、陰雨天氣O3濃度低。

關(guān)鍵詞:臭氧;環(huán)境空氣;輻射

來(lái)源出版物:環(huán)境科學(xué), 2004, 25(6): 16-19

被引頻次:87

上海夏季近地面臭氧濃度及其相關(guān)氣象因子的分析和預(yù)報(bào)

談建國(guó),陸國(guó)良,耿福海,等

摘要:為了揭示城市近地面臭氧濃度的變化特征及其相關(guān)氣象因素,嘗試進(jìn)行近地面臭氧濃度預(yù)報(bào)。通過(guò)對(duì)2005年夏季(6—9月上旬)上海徐家匯地區(qū)近地面臭氧的觀測(cè)與分析,建立了用于夏季臭氧濃度預(yù)報(bào)和高濃度臭氧污染事件預(yù)警的一種簡(jiǎn)便、實(shí)用的統(tǒng)計(jì)回歸方法。結(jié)果表明:天氣條件對(duì)臭氧形成具有明顯的作用,臭氧濃度晴天最大、多云天次之、陰雨天最??;臭氧具有明顯的日變化特征,12 : 00—14 : 00之間為最大值,凌晨3 : 00—5 : 00之間有一很小的次峰,5 : 00—6 : 00之間為最小值。產(chǎn)生高濃度臭氧污染是多項(xiàng)因子的綜合結(jié)果,一般在高壓系統(tǒng)的影響下,晴天少云,紫外輻射較強(qiáng),相對(duì)濕度較低,氣溫較高,地面和高空吹偏北風(fēng),且風(fēng)速較小的情形時(shí)容易產(chǎn)生高濃度臭氧污染。引進(jìn)高濃度臭氧潛勢(shì)指數(shù)和風(fēng)向影響指數(shù)兩個(gè)指標(biāo),并綜合考慮多種氣象要素,通過(guò)逐步回歸建立的臭氧濃度預(yù)報(bào)方程,對(duì)逐日最大臭氧濃度具有較好的擬合效果和可預(yù)報(bào)性。

關(guān)鍵詞:臭氧濃度;氣象因子;變化特征;臭氧預(yù)報(bào)

來(lái)源出版物:熱帶氣象學(xué)報(bào), 2007, 23(5): 515-520

被引頻次:75

臭氧污染脅迫對(duì)農(nóng)作物生長(zhǎng)與產(chǎn)量的影響

金明紅,黃益宗

摘要:對(duì)國(guó)內(nèi)外近地層大氣的臭氧污染現(xiàn)狀進(jìn)行討論,綜述臭氧對(duì)農(nóng)作物生長(zhǎng)的影響。作物受O3傷害最典型的癥狀為葉片上散布棕色或黃褐色的細(xì)密點(diǎn)狀斑、壞死斑。在O3的脅迫下,作物呼吸作用增強(qiáng),光合作用受抑制。O3對(duì)葉片膜保護(hù)系統(tǒng)、氣孔開度、氮代謝、糖類、脂類和其它物質(zhì)的代謝也有影響。O3對(duì)農(nóng)作物產(chǎn)生危害的同時(shí),也往往導(dǎo)致農(nóng)作物產(chǎn)量下降。

關(guān)鍵詞:臭氧;農(nóng)作物;生長(zhǎng);產(chǎn)量;影響

來(lái)源出版物:生態(tài)環(huán)境, 2003, 12(4): 482-486

被引頻次:64

北京地區(qū)臭氧污染的來(lái)源分析

王雪松,李金龍,張遠(yuǎn)航,等

摘要:光化學(xué)煙霧污染是影響北京地區(qū)夏季空氣質(zhì)量的一個(gè)重要環(huán)境問(wèn)題。利用區(qū)域空氣質(zhì)量模式(CAMx)對(duì)2000年6月底至7月初發(fā)生在北京地區(qū)的臭氧污染過(guò)程進(jìn)行模擬,運(yùn)用臭氧源識(shí)別技術(shù)(OSAT)和地區(qū)臭氧評(píng)估技術(shù)(GOAT),量化了不同地區(qū)的污染源排放對(duì)北京市城近郊區(qū)臭氧污染的貢獻(xiàn),探討了周邊地區(qū)排放的臭氧貢獻(xiàn)方式問(wèn)題,分析了北京地區(qū)臭氧污染的化學(xué)機(jī)制特征。研究表明,北京地區(qū)臭氧污染分布存在顯著差異,并且具有明顯的區(qū)域性特征,定陵地區(qū)的超標(biāo)臭氧主要受到城近郊區(qū)煙羽的嚴(yán)重影響(占 55%),城近郊區(qū)則除了受到北京市的前體物排放影響外(占

46%),來(lái)自天津市、河北省南部地區(qū)的貢獻(xiàn)往往也占有重要份額;周邊地區(qū)對(duì)北京市城近郊區(qū)的貢獻(xiàn)中,直接輸入的臭氧約占7層,其余部分以輸入前體物的方式貢獻(xiàn)臭氧;北京城近郊區(qū)的臭氧生成主要受揮發(fā)性有機(jī)物控制,而在遠(yuǎn)郊區(qū)縣和農(nóng)村地區(qū)臭氧生成對(duì)氮氧化物變得更為敏感。對(duì)北京地區(qū)臭氧污染的源排放控制,需要綜合考慮各種臭氧來(lái)源和不同貢獻(xiàn)方式的重要性,以及臭氧生成機(jī)制的變化規(guī)律。

關(guān)鍵詞:北京;臭氧;源貢獻(xiàn);源排放

來(lái)源出版物:中國(guó)科學(xué)B輯:化學(xué), 2009, 39(6): 548-559

被引頻次:1482

來(lái)源出版物:Lancet, 2002, 360(9341): 1233-1242被引頻次:787

Rethinking organic aerosols: Semivolatile emissions and photochemical aging

Robinson, Allen L; Donahue, Neil M; Shrivastava, Manish K; et al.

Abstract:Most primary organic-particulate emissions are semivolatile; thus, they partially evaporate with atmospheric dilution, creating substantial amounts of low-volatility gas-phase material. Laboratory experiments show that photo-oxidation of diesel emissions rapidly generates organic aerosol, greatly exceeding the contribution from known secondary organic-aerosol precursors. We attribute this unexplained secondary organic-aerosol production to the oxidation of low-volatility gas-phase species. Accounting for partitioning and photochemical processing of primary emissions creates a more regionally distributed aerosol and brings model predictions into better agreement with observations. Controlling organic particulate-matter concentrations will require substantial changes in the approaches that are currently used to measure and regulate emissions.

來(lái)源出版物:Science, 2007, 315(5816): 1259-1262

被引頻次:715

Evaluated kinetic, photochemical and heterogeneous data for atmospheric chemistry 5. IUPAC Subcommittee on gas kinetic data evaluation for atmospheric chemistry

Atkinson, R; Baulch, DL; Cox, RA; et al.

Abstract:This paper updates and extends previous critical evaluations of the kinetics and photochemistry of gas-phase chemical reactions of neutral species involved in atmospheric chemistry. The work has been carried out by the authors under the auspices of the IUPAC Subcommittee on Gas Phase Kinetic Data Evaluation for Atmospheric Chemistry. Data sheets have been prepared for 658 thermal and photochemical reactions, containing summaries of the available experimental data with notes giving details of the experimental procedures. For each reaction, a preferred value of the rate coefficient at 298 K is given together with a temperature dependence where possible. The selection of the preferred value is discussed and estimates of the accuracies of the rate coefficients and temperature coefficients have been made for each reaction. The data sheets are intended to provide the basic physical chemical data needed as input for calculations which modelatmospheric chemistry. A table summarizing the preferred rate data is provided, together with an appendix listing the available data on enthalpies of formation of the reactant and product species. We have also included for the first time in this series of evaluations a section on heterogeneous reactions of importance in atmospheric chemistry.

關(guān)鍵詞:air pollution; atmospheric chemistry; chemical kinetics; data evaluation; gas phase; heterogeneous atmospheric reactions; photoabsorption cross-section, photochemistry; quantum yield; rate coefficient

來(lái)源出版物:Journal of Physical and Chemical Reference Data, 1997, 26(3): 521-1011

被引頻次:405

Multimodel ensemble simulations of present-day and near-future tropospheric ozone

Stevenson, DS; Dentener, FJ; Schultz, MG; et al.

Abstract:Global tropospheric ozone distributions, budgets, and radiative forcings from an ensemble of 26 state-of-the-art atmospheric chemistry models have been intercompared and synthesized as part of a wider study into both the air quality and climate roles of ozone. Results from three 2030 emissions scenarios, broadly representing “optimistic,” “l(fā)ikely,” and “pessimistic” options, are compared to a base year 2000 simulation. This base case realistically represents the current global distribution of tropospheric ozone. A further set of simulations considers the influence of climate change over the same time period by forcing the central emissions scenario with a surface warming of around 0.7 K. The use of a large multimodel ensemble allows us to identify key areas of uncertainty and improves the robustness of the results. Ensemble mean changes in tropospheric ozone burden between 2000 and 2030 for the 3 scenarios range from a 5% decrease, through a 6% increase, to a 15% increase. The intermodel uncertainty (±1 standard deviation) associated with these values is about ±25%. Model outliers have no significant influence on the ensemble mean results. Combining ozone and methane changes, the three scenarios produce radiative forcings of ﹣50, 180, and 300 mW m-2, compared to a CO2forcing over the same time period of 800-1100 mW m-2. These values indicate the importance of air pollution emissions in short-to medium-term climate forcing and the potential for stringent/lax control measures to improve/ worsen future climate forcing. The model sensitivity of ozone to imposed climate change varies between models but modulates zonal mean mixing ratios by ±5 ppbv via a variety of feedback mechanisms, in particular those involving water vapor and stratosphere-troposphere exchange. This level of climate change also reduces the methane lifetime by around 4%. The ensemble mean year 2000 tropospheric ozone budget indicates chemical production, chemical destruction, dry deposition and stratospheric input fluxes of 5100, 4650, 1000, and 550 Tg(O3) yr-1, respectively. These values are significantly different to the mean budget documented by the Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report (TAR). The mean ozone burden (340 Tg(O3) is 10% larger than the IPCC TAR estimate, while the mean ozone lifetime (22 days) is 10% shorter. Results from individual models show a correlation between ozone burden and lifetime, and each model's ozone burden and lifetime respond in similar ways across the emissions scenarios. The response to climate change is much less consistent. Models show more variability in the tropics compared to midlatitudes. Some of the most uncertain areas of the models include treatments of deep tropical convection, including lightning NOx production; isoprene emissions from vegetation and isoprene’s degradation chemistry; stratosphere-troposphere exchange; biomass burning; and water vapor concentrations.

來(lái) 源 出 版 物 : Journal of Geophysical Research-Atmospheres, 2006, 111(D8): D08301

被引頻次:585

A review of surface ozone background levels and trends

Vingarzan, R

Abstract:A survey of the literature was conducted to review historical and current surface ozone data from background stations in Canada, United States and around the world for the purpose of characterizing background levels and trends, present plausible explanations for observed trends and explore projections of future ozone levels. The annual ozone cycle at background sites in the Northern Hemisphere is characterized by a spring maximum, peaking during the month of May. Although presently there is no concensus as to the origin of the spring maximum, evidence supports both enhanced photochemistry in the free troposphere and stratospheric input. Modern day annual average background ozone concentrations over the midlatitudes of the Northern Hemisphere range between approximately 20-45 ppb,with variability being a function of geographic location, elevation and extent of anthropogenic influence. Annual median ozone levels at Canadian background stations fall between 23 and 34 ppb, a range similar to that reported for low-elevation background stations in the United States and around the world. Comparisons of ozone levels with those measured over a century ago indicate that current levels have increased by approximately two times. Although current trends are not uniform, there is some indication that background ozone levels over the midlatitudes of the Northern Hemisphere have continued to rise over the past three decades, and that this rise has been in the range of approximately 0.5%-2% per year. Rising trends were steeper in the 1970s and 1980s compared to the 1990s, which have seen either a leveling off or a decline in the magnitude of these trends. Model sensitivity studies indicate that the rise in NO, emissions account for the greatest increase in background ozone levels over the past three decades. A substantial component of the background ozone concentration in western North America may be due to long-range transport of Asian pollution, especially during the spring months. Model projections using IPCC emission scenarios for the 21st century indicate that background ozone may rise to levels that would exceed internationally accepted environmental criteria for human health and the environment.

關(guān) 鍵 詞 :background ozone; ozone trends; spring maximum; tropospheric ozone; ozone projections

來(lái)源出版物:Atmospheric Environment, 2004, 38(21): 3431-3442

被引頻次:306

What controls tropospheric ozone?

Lelieveld, J; Dentener, FJ

Abstract:We have applied a global three-dimensional chemistry-transport model to quantify the photochemistry of tropospheric O3and compare the main source categories. We simulated a 15 year period (1979-1993) on the basis of the European Centre for Medium-Range Weather Forecasts meteorological reanalyses and a time- varying emission data set. We calculate that stratosphere-troposphere exchange (STE) strongly contributes to O3in regions where the photochemistry is quiescent. Since such regions play a minor role in radiative and chemical processes, we argue that STE-derived O3is much less important than is suggested by its column abundance. By distinguishing between photochemical pathways in the model we calculate that tropospheric O3in the extratropical Northern Hemisphere is strongly affected by industrial and fossil fuel-related emissions. In the tropics and Southern Hemisphere, natural emissions still play a major role. Our model results indicate a less important role for man-made biomass burning emissions than previous analyses. Further, the results show that tropospheric O3trends are strongly influenced by transports of pollution and by meteorological variability. Scenario calculations for the year 2025 suggest that man-made emissions at low northern latitudes, in particular in southern and eastern Asia, will become a very strong tropospheric O3source in the next decades. This will influence O3levels on a hemispheric scale so that despite pollution regulations in Europe and North America, surface O3will continue to grow.

來(lái)源出版物:Journal of Geophysical Research-Atmospheres, 2000, 105(D3): 3531-3551

被引頻次:291

Megacities and atmospheric pollution

Molina, MJ; Molina, LT

Abstract:About half of the world’s population now lives in urban areas because of the opportunity for a better quality of life. Many of these urban centers are expanding rapidly, leading to the growth of megacities, which are defined as metropolitan areas with populations exceeding 10 million inhabitants. These concentrations of people and activity are exerting increasing stress on the natural environment, with impacts at urban, regional and global levels. In recent decades, air pollution has become one of the most important problems of megacities. Initially, the main air pollutants of concern were sulfur compounds, which were generated mostly by burning coal. Today, photochemical smog-induced primarily from traffic, but also from industrial activities, power generation, and solvents-has become the main source of concern for air quality, while sulfur is still a major problem in many cities of the developing world. Air pollution has serious impacts on public health, causes urban and regional haze, and has the potential to contribute significantly to climate change. Yet, with appropriate planning, megacities can efficiently address their air quality problems through measures such as application of new emission control technologies and development of mass transit systems.

來(lái)源出版物:Journal of the Air & Waste Management Association, 2004, 54(6): 644-680

被引頻次:283

A meta-analysis of time-series studies of ozone and mortality with comparison to the national morbidity, mortality, and air pollution study

Bell, ML; Dominici, F; Samet, JM; et al.

Abstract:Background: Although many time-series studies of ozone and mortality have identified positive associations, others have yielded null or inconclusive results, making the results of these studies difficult to interpret. Methods: We performed a meta-analysis of 144 effect estimates from 39 time-series studies, and estimated pooled effects by lags, age groups, cause-specific mortality, and concentration metrics. We compared results with pooled estimates from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS), a time-series study of 95 large U.S. urban centers from 1987 to 2000. Results: Both meta-analysis and NMMAPS results provided strong evidence of a short-term association between ozone and mortality, with larger effects for cardiovascular and respiratory mortality, the elderly, and current-day ozone exposure. In both analyses, results were insensitive to adjustment for particulate matter and model specifications. In the meta-analysis, a 10-ppb increase in daily ozone at single-day or 2-day average of lags 0, 1, or 2 days was associated with an 0.87% increase in total mortality (95% posterior interval = 0.55% to 1.18%), whereas the lag 0 NMMAPS estimate is 0.25% (0.12% to 0.39%). Several findings indicate possible publication bias: meta-analysis results were consistently larger than those from NMMAPS; meta-analysis pooled estimates at lags 0 or 1 were larger when only a single lag was reported than when estimates for multiple lags were reported; and heterogeneity of city-specific estimates in the meta-analysis were larger than with NMMAPS.

來(lái)源出版物:Epidemiology, 2005, 16(4): 436-445

被引頻次:274

Effect of rising Asian emissions on surface ozone in the United States

Jacob, DJ; Logan, JA; Murti, PP; et al.

Abstract:The effect of increasing fossil fuel combustion in eastern Asia on surface O3air pollution in the United States is examined with a global three-dimensional tropospheric chemistry model. Tripling of Asian anthropogenic emissions from 1985 to 2010 is expected to increase monthly mean O3concentrations by 2-6 ppbv in the western United States and by 1-3 ppbv in the eastern United States, the maximum effect being in April-June. This increase would more than offset the benefits of 25% domestic reductions in anthropogenic emissions of NOxand hydrocarbons in the western United States. Asian influence may be less under the stagnant conditions leading to violations of the U.S. air quality standard. Nevertheless, our results suggest that a global perspective is necessary when designing a strategy to meet regional O3air quality objectives.

來(lái)源出版物:Geophysical Research Letters, 1999, 426(14): 2175-2178

Air pollution and health

Brunekreef, B; Holgate, ST

The health effects of air pollution have been subject to intense study in recent years. Exposure to pollutants such as airborne particulate matter and ozone has been associated with increases in mortality and hospital admissions due to respiratory and cardiovascular disease. These effects have been found in short-term studies, which relate day-to-day variations in air pollution and health, and long-term studies, which have followed cohorts of exposed individuals over time. Effects have been seen at very low levels of exposure, and it is unclear whether a threshold concentration exists for particulate matter and ozone below which no effects on health are likely. In this review, we discuss the evidence for adverse effects on health of selected air pollutants.

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