Simulation of the effects of low volatility organic compounds on aerosol number concentrations in Europe

Organic Vapors ◽

Chemical Aging ◽

Po Valley ◽

Small Change

Abstract. PMCAMx-UF, a three-dimensional chemical transport model focusing on the simulation of the ultrafine particle size distribution and composition has been extended with the addition of reactions of chemical aging of semi-volatile anthropogenic organic vapors, the emissions and chemical aging by intermediate volatile organic compounds (IVOCs) and the production of extremely low volatility organic compounds (ELVOCs) by monoterpenes. The model is applied in Europe to quantify the effect of these processes on particle number concentrations. The model predictions are evaluated against both ground measurements collected during the PEGASOS 2012 summer campaign across many stations in Europe and airborne observations by a Zeppelin measuring above Po-Valley, Italy. PMCAMx-UF reproduces the ground level daily average concentrations of particles larger than 100 nm (N100) with normalized mean error (NME) of 45 % and normalized mean bias (NMB) close to 10 %. For the same simulation, PMCAMx-UF tends to overestimate the concentration of particles larger than 10 nm (N10) with a daily NMB of 23 % and a daily NME of 63 %. The model was able to reproduce more than 75 % of the N10 and N100 airborne observations (Zeppelin) within a factor of 2. The ELVOC production by monoterpenes is predicted to lead to surprisingly small changes of the average number concentrations over Europe. The total number concentration decreased due to the ELVOC formation by 0.2 %, the N10 decreases by 1.1 %, while N50 increased by 3 % and N100 by 4 % due to this new SOA source. This small change is due to the nonlinearity of the system with increases predicted in some areas and decreases in others, but also the cancelation of the effects of the various processes like accelerated growth and accelerated coagulation. Locally, the effects can be significant. For example, an increase in N100 by 20–50 % is predicted over Scandinavia and significant increases (10–20 %) over some parts of central Europe. The ELVOCs contributed on average around 0.5 μg m−3 and accounted for 10–15 % of the PM2.5 OA. The addition of IVOC emissions and their aging reactions led to surprising reduction of the total number of particles (Ntot) and N10 by 10–15 and 5–10 %, respectively, and to an increase of the concentration of N100 by 5–10 %. These were due to the accelerated coagulation and reduced nucleation rates.

The size-composition distribution of atmospheric nanoparticles over Europe

10.5194/acp-2018-73 ◽

2018 ◽

Author(s):

David Patoulias ◽

Christos Fountoukis ◽

Ilona Riipinen ◽

Ari Asmi ◽

Markku Kulmala ◽

...

Keyword(s):

Ultrafine Particles ◽

Transport Model ◽

Ultrafine Particle ◽

Three Dimensional ◽

Size Composition ◽

Ground Level ◽

Basis Set ◽

Airborne Measurements ◽

Po Valley

Abstract. PMCAMx-UF, a three-dimensional chemical transport model focusing on the simulation of the ultrafine particle size distribution and composition has been extended with the addition of the volatility basis set (VBS) approach for the simulation of organic aerosol (OA). The model was applied in Europe to quantify the effect of secondary semi-volatile organic vapors on particle number concentrations. The model predictions were evaluated against field observations collected during the PEGASOS-2012 campaign. The measurements included both ground and airborne measurements, from stations across Europe and a Zeppelin measuring above Po-Valley. The ground level concentrations of particles larger than 100 nm (N100) were reproduced with a daily normalized mean error of 40 % and a daily normalized mean bias of −20 %. PMCAMx-UF tended to overestimate the concentration of particles larger than 10 nm (N10) with a daily normalized mean bias of 75 %. The model performed quite well compared to the Zeppelin measurements, reproducing more than 85 % of N10 and 75 % of the N100 data, within a factor of 2. The condensation of organics led to an increase (50–120 %) of the N100 concentration mainly in central and northern Europe, while the N10 concentration decreased by 10–30 %. Including the VBS in the PMCAMx-UF improved its ability to simulate aerosol number concentration compared to simulations neglecting organic condensation on ultrafine particles.

Simulation of the size-composition distribution of atmospheric nanoparticles over Europe

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-13639-2018 ◽

2018 ◽

Vol 18 (18) ◽

pp. 13639-13654 ◽

Cited By ~ 4

Author(s):

David Patoulias ◽

Christos Fountoukis ◽

Ilona Riipinen ◽

Ari Asmi ◽

Markku Kulmala ◽

...

Keyword(s):

Ultrafine Particles ◽

Transport Model ◽

Ultrafine Particle ◽

Three Dimensional ◽

Size Composition ◽

Ground Level ◽

Basis Set ◽

Airborne Measurements ◽

Po Valley

Abstract. PMCAMx-UF, a three-dimensional chemical transport model focusing on the simulation of the ultrafine particle size distribution and composition has been extended with the addition of the volatility basis set (VBS) approach for the simulation of organic aerosol (OA). The model was applied in Europe to quantify the effect of secondary semi-volatile organic vapors on particle number concentrations. The model predictions were evaluated against field observations collected during the PEGASOS 2012 campaign. The measurements included both ground and airborne measurements, from stations across Europe and a zeppelin measuring above Po Valley. The ground level concentrations of particles with a diameter larger than 100 nm (N100) were reproduced with a daily normalized mean error of 40 % and a daily normalized mean bias of −20 %. PMCAMx-UF tended to overestimate the concentration of particles with a diameter larger than 10 nm (N10) with a daily normalized mean bias of 75 %. The model was able to reproduce, within a factor of 2, 85 % of the N10 and 75 % of the N100 zeppelin measurements above ground. The condensation of organics led to an increase (50 %–120 %) in the N100 concentration mainly in central and northern Europe, while the N10 concentration decreased by 10 %–30 %. Including the VBS in PMCAMx-UF improved its ability to simulate aerosol number concentration compared to simulations neglecting organic condensation on ultrafine particles.

Evaluation of a three-dimensional chemical transport model (PMCAMx) in the European domain during the EUCAARI May 2008 campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-10331-2011 ◽

2011 ◽

Vol 11 (20) ◽

pp. 10331-10347 ◽

Cited By ~ 90

Author(s):

C. Fountoukis ◽

P. N. Racherla ◽

H. A. C. Denier van der Gon ◽

P. Polymeneas ◽

P. E. Charalampidis ◽

...

Keyword(s):

Time Resolution ◽

Transport Model ◽

Three Dimensional ◽

Model Performance ◽

Ground Level ◽

Chemical Transport ◽

Organic Aerosol ◽

High Time Resolution ◽

Airborne Measurements

Abstract. PMCAMx-2008, a detailed three-dimensional chemical transport model (CTM), was applied to Europe to simulate the mass concentration and chemical composition of particulate matter (PM) during May 2008. The model includes a state-of-the-art organic aerosol module which is based on the volatility basis set framework treating both primary and secondary organic components as semivolatile and photochemically reactive. The model performance is evaluated against high time resolution aerosol mass spectrometer (AMS) ground and airborne measurements. Overall, organic aerosol is predicted to account for 32% of total PM1 at ground level during May 2008, followed by sulfate (30%), crustal material and sea-salt (14%), ammonium (13%), nitrate (7%), and elemental carbon (4%). The model predicts that fresh primary OA (POA) is a small contributor to organic PM concentrations in Europe during late spring, and that oxygenated species (oxidized primary and biogenic secondary) dominate the ambient OA. The Mediterranean region is the only area in Europe where sulfate concentrations are predicted to be much higher than the OA, while organic matter is predicted to be the dominant PM1 species in central and northern Europe. The comparison of the model predictions with the ground measurements in four measurement stations is encouraging. The model reproduces more than 94% of the daily averaged data and more than 87% of the hourly data within a factor of 2 for PM1 OA. The model tends to predict relatively flat diurnal profiles for PM1 OA in many areas, both rural and urban in agreement with the available measurements. The model performance against the high time resolution airborne measurements at multiple altitudes and locations is as good as its performance against the ground level hourly measurements. There is no evidence of missing sources of OA aloft over Europe during this period.

Evaluation of a three-dimensional chemical transport model (PMCAMx) in the European domain during the EUCAARI May 2008 campaign

10.5194/acpd-11-14183-2011 ◽

2011 ◽

Vol 11 (5) ◽

pp. 14183-14220 ◽

Cited By ~ 5

Author(s):

C. Fountoukis ◽

P. N. Racherla ◽

H. A. C. Denier van der Gon ◽

P. Polymeneas ◽

P. E. Haralabidis ◽

...

Keyword(s):

Time Resolution ◽

Transport Model ◽

Three Dimensional ◽

Model Performance ◽

Ground Level ◽

Chemical Transport ◽

Organic Aerosol ◽

High Time Resolution ◽

Airborne Measurements

Abstract. PMCAMx-2008, a detailed three dimensional chemical transport model (CTM), was applied to Europe to simulate the mass concentration and chemical composition of particulate matter (PM) during May 2008. The model includes a state-of-the-art organic aerosol module which is based on the volatility basis set framework treating both primary and secondary organic components to be semivolatile and photochemically reactive. The model performance is evaluated against high time resolution aerosol mass spectrometer (AMS) ground and airborne measurements. Overall, organic aerosol is predicted to account for 32% of total PM1 at ground level during May 2008, followed by sulfate (30%), crustal material and sea-salt (14%), ammonium (13%), nitrate (7%), and elemental carbon (4%). The model predicts that fresh primary OA (POA) is a small contributor to organic PM concentrations in Europe during late spring, and that oxygenated species (oxidized primary and biogenic secondary) dominate the ambient OA. The Mediterranean region is the only area in Europe where sulfate concentrations are predicted to be much higher than the OA, while organic matter is predicted to be the dominant PM1 species in Central and Northern Europe. The comparison of the model predictions with the ground measurements in four measurement stations is encouraging. The model reproduces more than 94% of the daily averaged data and more than 87% of the hourly data within a factor of 2 for PM1 OA. The model tends to predict relatively flat diurnal profiles for PM1 OA in many areas, both rural and urban, in agreement with the available measurements. The model performance against the high time resolution airborne measurements at multiple altitudes and locations is as good as its performance against the ground level hourly measurements. There is no evidence of missing sources of OA aloft over Europe during this period.

The UIUC three-dimensional stratospheric chemical transport model: Description and evaluation of the simulated source gases and ozone

Journal of Geophysical Research Atmospheres ◽

10.1029/1999jd900138 ◽

1999 ◽

Vol 104 (D9) ◽

pp. 11755-11781 ◽

Cited By ~ 67

Author(s):

Eugene V. Rozanov ◽

Vladimir A. Zubov ◽

Michael E. Schlesinger ◽

Fanglin Yang ◽

Natalia G. Andronova

Keyword(s):

Transport Model ◽

Three Dimensional ◽

Chemical Transport ◽

Model Description ◽

Simulated Source

Implementation of state-of-the-art ternary new-particle formation scheme to the regional chemical transport model PMCAMx-UF in Europe

Geoscientific Model Development ◽

10.5194/gmd-9-2741-2016 ◽

2016 ◽

Vol 9 (8) ◽

pp. 2741-2754 ◽

Cited By ~ 8

Author(s):

Elham Baranizadeh ◽

Benjamin N. Murphy ◽

Jan Julin ◽

Saeed Falahat ◽

Carly L. Reddington ◽

...

Keyword(s):

Transport Model ◽

Three Dimensional ◽

Chemical Transport ◽

Particle Formation ◽

Radiative Transfer Model ◽

Transfer Model ◽

New Particle Formation ◽

Order Of Magnitude ◽

Adjustment Scheme

Abstract. The particle formation scheme within PMCAMx-UF, a three-dimensional chemical transport model, was updated with particle formation rates for the ternary H2SO4–NH3–H2O pathway simulated by the Atmospheric Cluster Dynamics Code (ACDC) using quantum chemical input data. The model was applied over Europe for May 2008, during which the EUCAARI-LONGREX (European Aerosol Cloud Climate and Air Quality Interactions–Long-Range Experiment) campaign was carried out, providing aircraft vertical profiles of aerosol number concentrations. The updated model reproduces the observed number concentrations of particles larger than 4 nm within 1 order of magnitude throughout the atmospheric column. This agreement is encouraging considering the fact that no semi-empirical fitting was needed to obtain realistic particle formation rates. The cloud adjustment scheme for modifying the photolysis rate profiles within PMCAMx-UF was also updated with the TUV (Tropospheric Ultraviolet and Visible) radiative-transfer model. Results show that, although the effect of the new cloud adjustment scheme on total number concentrations is small, enhanced new-particle formation is predicted near cloudy regions. This is due to the enhanced radiation above and in the vicinity of the clouds, which in turn leads to higher production of sulfuric acid. The sensitivity of the results to including emissions from natural sources is also discussed.

Model sensitivity studies of the decrease in atmospheric carbon tetrachloride

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-15741-2016 ◽

2016 ◽

Vol 16 (24) ◽

pp. 15741-15754 ◽

Cited By ~ 4

Author(s):

Martyn P. Chipperfield ◽

Qing Liang ◽

Matthew Rigby ◽

Ryan Hossaini ◽

Stephen A. Montzka ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Transport Model ◽

Three Dimensional ◽

Montreal Protocol ◽

Uncertainty Range ◽

The Past ◽

Systematic Biases ◽

Lifetime Uncertainty ◽

The Impact

Abstract. Carbon tetrachloride (CCl4) is an ozone-depleting substance, which is controlled by the Montreal Protocol and for which the atmospheric abundance is decreasing. However, the current observed rate of this decrease is known to be slower than expected based on reported CCl4 emissions and its estimated overall atmospheric lifetime. Here we use a three-dimensional (3-D) chemical transport model to investigate the impact on its predicted decay of uncertainties in the rates at which CCl4 is removed from the atmosphere by photolysis, by ocean uptake and by degradation in soils. The largest sink is atmospheric photolysis (74 % of total), but a reported 10 % uncertainty in its combined photolysis cross section and quantum yield has only a modest impact on the modelled rate of CCl4 decay. This is partly due to the limiting effect of the rate of transport of CCl4 from the main tropospheric reservoir to the stratosphere, where photolytic loss occurs. The model suggests large interannual variability in the magnitude of this stratospheric photolysis sink caused by variations in transport. The impact of uncertainty in the minor soil sink (9 % of total) is also relatively small. In contrast, the model shows that uncertainty in ocean loss (17 % of total) has the largest impact on modelled CCl4 decay due to its sizeable contribution to CCl4 loss and large lifetime uncertainty range (147 to 241 years). With an assumed CCl4 emission rate of 39 Gg year−1, the reference simulation with the best estimate of loss processes still underestimates the observed CCl4 (overestimates the decay) over the past 2 decades but to a smaller extent than previous studies. Changes to the rate of CCl4 loss processes, in line with known uncertainties, could bring the model into agreement with in situ surface and remote-sensing measurements, as could an increase in emissions to around 47 Gg year−1. Further progress in constraining the CCl4 budget is partly limited by systematic biases between observational datasets. For example, surface observations from the National Oceanic and Atmospheric Administration (NOAA) network are larger than from the Advanced Global Atmospheric Gases Experiment (AGAGE) network but have shown a steeper decreasing trend over the past 2 decades. These differences imply a difference in emissions which is significant relative to uncertainties in the magnitudes of the CCl4 sinks.

Estimating ground-level PM<sub>2.5</sub> in Eastern China using aerosol optical depth determined from the GOCI Satellite Instrument

10.5194/acpd-15-17251-2015 ◽

2015 ◽

Vol 15 (12) ◽

pp. 17251-17281 ◽

Cited By ~ 4

Author(s):

J. Xu ◽

R. V. Martin ◽

A. van Donkelaar ◽

J. Kim ◽

M. Choi ◽

...

Keyword(s):

Organic Matter ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Transport Model ◽

Eastern China ◽

Ground Level ◽

East China ◽

Near Surface ◽

Significant Agreement

Abstract. We determine and interpret fine particulate matter (PM2.5) concentrations in East China for January to December 2013 at a horizontal resolution of 6 km from aerosol optical depth (AOD) retrieved from the Korean Geostationary Ocean Color Imager (GOCI) satellite instrument. We implement a set of filters to minimize cloud contamination in GOCI AOD. Evaluation of filtered GOCI AOD with AOD from the Aerosol Robotic Network (AERONET) indicates significant agreement with mean fractional bias (MFB) in Beijing of 6.7 % and northern Taiwan of −1.2 %. We use a global chemical transport model (GEOS-Chem) to relate the total column AOD to the near-surface PM2.5. The simulated PM2.5/AOD ratio exhibits high consistency with ground-based measurements (MFB = −0.52–8.0 %). We evaluate the satellite-derived PM2.5 vs. the ground-level PM2.5 in 2013 measured by the China Environmental Monitoring Center. Significant agreement is found between GOCI-derived PM2.5 and in-situ observations in both annual averages (r = 0.81, N = 494) and monthly averages (MFB = 13.1 %), indicating GOCI provides valuable data for air quality studies in Northeast Asia. The GEOS-Chem simulated chemical speciation of GOCI-derived PM2.5 reveals that secondary inorganics (SO42−, NO3−, NH4+) and organic matter are the most significant components. Biofuel emissions in northern China for heating are responsible for an increase in the concentration of organic matter in winter. The population-weighted GOCI-derived PM2.5 over East China for 2013 is 53.8 μg m−3, threatening the health and life expectancy of its 600 million residents.

Modeling the transport of very short-lived substances into the tropical upper troposphere and lower stratosphere

10.5194/acpd-9-18511-2009 ◽

2009 ◽

Vol 9 (5) ◽

pp. 18511-18543 ◽

Cited By ~ 2

Author(s):

J. Aschmann ◽

B. M. Sinnhuber ◽

E. L. Atlas ◽

S. M. Schauffler

Keyword(s):

Large Scale ◽

Lower Stratosphere ◽

Transport Model ◽

Three Dimensional ◽

Heating Rates ◽

Model Calculations ◽

Upper Troposphere ◽

Mass Fluxes ◽

Tropical Upper Troposphere

Abstract. The transport of very short-lived substances into the tropical upper troposphere and lower stratosphere is investigated by a three-dimensional chemical transport model using archived convective updraft mass fluxes (or detrainment rates) from the European Centre for Medium-Range Weather Forecast's ERA-Interim reanalysis. Large-scale vertical velocities are calculated from diabatic heating rates. With this approach we explicitly model the large scale subsidence in the tropical troposphere with convection taking place in fast and isolated updraft events. The model calculations agree generally well with observations of bromoform and methyl iodide from aircraft campaigns and with ozone and water vapor from sonde and satellite observations. Using a simplified treatment of dehydration and bromine product gas washout we give a range of 1.6 to 3 ppt for the contribution of bromoform to stratospheric bromine, assuming a uniform source in the boundary layer of 1 ppt. We show that the most effective region for VSLS transport into the stratosphere is the West Pacific, accounting for about 55% of the bromine from bromoform transported into the stratosphere under the supposition of a uniformly distributed source.

A three-dimensional model study of long-term mid-high latitude lower stratosphere ozone changes

10.5194/acpd-3-1081-2003 ◽

2003 ◽

Vol 3 (1) ◽

pp. 1081-1107 ◽

Cited By ~ 1

Author(s):

M. P. Chipperfield

Keyword(s):

High Latitude ◽

Lower Stratosphere ◽

Transport Model ◽

Three Dimensional ◽

Horizontal Resolution ◽

Three Dimensional Model ◽

Detailed Chemistry ◽

Basic Model ◽

Column Ozone

Abstract. We have used a 3D off-line chemical transport model (CTM) to study the causes of the observed changes in ozone in the mid-high latitude lower stratosphere from 1979–1998. The model was forced by European Centre for Medium Range Weather Forecasts (ECMWF) analyses and contains a detailed chemistry scheme. A series of model runs were performed at a horizontal resolution of 7.5°×7.5° and covered the domain from about 12 km to 30 km. The basic model performs well in reproducing the decadal evolution of the springtime depletion in the northern hemisphere (NH) and southern hemisphere (SH) high latitudes in the 1980s and early 1990s. After about 1994 the modelled interannual variability does not match the observations as well, which is probably due in part to changes in the operational ECMWF analyses – which places limits on using this dataset to diagnose dynamical trends. For mid-latitudes (35°–60°) the basic model reproduces the observed column ozone decreases from 1980 until the early 1990s. Model experiments show that the halogen trends appear to dominate this modelled decrease and of this around 30–50% is due to high-latitude processing on polar stratospheric clouds (PSCs). Dynamically induced ozone variations in the model correlate with observations over the timescale of a few years. Large discrepancies between the modelled and observed variations in the mid 1980s and mid 1990s can be largely resolved by assuming that the 11-year solar cycle (not explicitly included in the 3D model) causes a 2% (min-max) change in mid-latitude column ozone.