A statistical long-range transport model for simulation of wet sulphate deposition

1989 ◽  
Vol 16 (3) ◽  
pp. 258-266 ◽  
Author(s):  
J. M. Byrne ◽  
E. A. McBean ◽  
K. B. Shipley ◽  
G. J. Farquhar
Keyword(s):  
Long Range ◽  
Transport Model ◽  
Long Range Transport ◽  
Central Processor ◽  
Central Processor Unit ◽  
Range Transport ◽  
Sulphate Deposition ◽  
Time Requirements ◽  
Processor Unit ◽  
Relative Errors

A statistical long-range transport of air pollutants model (UW-LRT) is utilized to simulate wet SO4 deposition in eastern North America in 1980. Model results compare favorably to an analyzed deposition field. In a comparison of the relative errors associated with four long-range transport models, the UW-LRT model demonstrates the lowest variation from recorded, analyzed deposition data. The UW-LRT model has modest data input and central processor unit time requirements. Key words: acid rain, long-range transport, spatial deposition, mathematical models.

scholarly journals Inverse modelling-based reconstruction of the Chernobyl source term available for long-range transport

2007 ◽  
Vol 7 (6) ◽  
pp. 1549-1564 ◽  
Author(s):  
X. Davoine ◽  
M. Bocquet
Keyword(s):  
Long Range ◽  
Activity Concentration ◽  
Source Term ◽  
Transport Model ◽  
Mass Scale ◽  
Inverse Modelling ◽  
Long Range Transport ◽  
Activity Measurements ◽  
Range Transport ◽  
Two Parameters

Abstract. The reconstruction of the Chernobyl accident source term has been previously carried out using core inventories, but also back and forth confrontations between model simulations and activity concentration or deposited activity measurements. The approach presented in this paper is based on inverse modelling techniques. It relies both on the activity concentration measurements and on the adjoint of a chemistry-transport model. The location of the release is assumed to be known, and one is looking for a source term available for long-range transport that depends both on time and altitude. The method relies on the maximum entropy on the mean principle and exploits source positivity. The inversion results are mainly sensitive to two tuning parameters, a mass scale and the scale of the prior errors in the inversion. To overcome this hardship, we resort to the statistical L-curve method to estimate balanced values for these two parameters. Once this is done, many of the retrieved features of the source are robust within a reasonable range of parameter values. Our results favour the acknowledged three-step scenario, with a strong initial release (26 to 27 April), followed by a weak emission period of four days (28 April–1 May) and again a release, longer but less intense than the initial one (2 May–6 May). The retrieved quantities of iodine-131, caesium-134 and caesium-137 that have been released are in good agreement with the latest reported estimations. Yet, a stronger apportionment of the total released activity is ascribed to the first period and less to the third one. Finer chronological details are obtained, such as a sequence of eruptive episodes in the first two days, likely related to the modulation of the boundary layer diurnal cycle. In addition, the first two-day release surges are found to have effectively reached an altitude up to the top of the domain (5000 m).

scholarly journals Systematic analysis of tropospheric NO<sub>2</sub> long-range transport events detected in GOME-2 satellite data

2014 ◽  
Vol 14 (14) ◽  
pp. 7367-7396 ◽  
Author(s):  
A. W. Zien ◽  
A. Richter ◽  
A. Hilboll ◽  
A.-M. Blechschmidt ◽  
J. P. Burrows
Keyword(s):  
Long Range ◽  
Transport Model ◽  
Meteorological Data ◽  
Long Range Transport ◽  
Emission Region ◽  
Systematic Analysis ◽  
Range Transport ◽  
Tropospheric No2 ◽  
High Emission ◽  
Autumn And Winter

Abstract. Intercontinental long-range transport (LRT) events of NO2 relocate the effects of air pollution from emission regions to remote, pristine regions. We detect transported plumes in tropospheric NO2 columns measured by the GOME-2/MetOp-A instrument with a specialized algorithm and trace the plumes to their sources using the HYSPLIT Lagrangian transport model. With this algorithm we find 3808 LRT events over the ocean for the period 2007 to 2011. LRT events occur frequently in the mid-latitudes, emerging usually from coastal high-emission regions. In the free troposphere, plumes of NO2 can travel for several days to the polar oceanic atmosphere or to other continents. They travel along characteristic routes and originate from both continuous anthropogenic emission and emission events such as bush fires. Most NO2 LRT events occur during autumn and winter months, when meteorological conditions and emissions are most favorable. The evaluation of meteorological data shows that the observed NO2 LRT is often linked to cyclones passing over an emission region.

scholarly journals Long range transport of mercury to the Arctic and across Canada

2010 ◽  
Vol 10 (2) ◽  
pp. 4673-4717 ◽  
Author(s):  
D. Durnford ◽  
A. Dastoor ◽  
D. Figueras-Nieto ◽  
A. Ryjkov
Keyword(s):  
North America ◽  
Long Range ◽  
Transport Model ◽  
Extensive Study ◽  
Atmospheric Mercury ◽  
The Arctic ◽  
Long Range Transport ◽  
Chemical Transport Model ◽  
Transport Pathways ◽  
Range Transport

Abstract. This study is the most extensive study to date on the transport of mercury to the Arctic. Moreover, it is the first such study to use a fully-coupled, online chemical transport model, Environment Canada's Global/Regional Atmospheric Heavy Metals model (GRAHM), where the meteorology and mercury processes are fully integrated. It is also the only study to date on the transport of mercury across Canada. We determined source attribution from Asia, North America, Russia and Europe at six arctic verification stations, as well as three subarctic and eight midlatitude Canadian stations. We have found that Asia, despite having transport efficiencies that were almost always lower than those of North America and often lower than those of Russia, was the dominant source of gaseous atmospheric mercury at all verification stations: it contributed the most mercury (29–37% at all stations, seasons and levels considered), its concentrations frequently explained nearly 100% of the variability in the concentrations produced by the simulation performed with full global emissions, particularly in the absence of local sources, and it generated the most long range transport (LRT) events, causing 43%, 67% and 75% of the events at the arctic, subarctic and midlatitude stations, respectively. For the Arctic, Russian transport efficiencies tended to be the strongest, as expected, while European and Asian efficiencies were lower and higher, respectively, than those found in the literature. This disagreement is likely produced by mercury's long lifetime relative to that of other pollutants. The accepted springtime preference for the trans-Pacific transport of Asian pollution was evident only in the midlatitude group of stations, being masked in the arctic and subarctic groups by the occurrence of atmospheric mercury depletion events. Some neighbouring arctic stations recorded dissimilar numbers of LRT events; despite their proximity, the behaviour of mercury at these stations was governed by different dynamics and transport pathways. The column burden of GEM in the lowest 5 km of the Northern Hemisphere was largest in summer from Asia, North America and Russia, but in winter from Europe. In the vertical, transport of mercury from all source regions occurred principally in the mid-troposphere.

scholarly journals Interannual variability of long-range transport as seen at the Mt. Bachelor Observatory

2008 ◽  
Vol 8 (4) ◽  
pp. 16335-16379 ◽  
Author(s):  
D. R. Reidmiller ◽  
D. A. Jaffe ◽  
D. Chand ◽  
S. Strode ◽  
P. Swartzendruber ◽  
...  
Keyword(s):  
Southeast Asia ◽  
Interannual Variability ◽  
Long Range ◽  
Biomass Burning ◽  
Transport Model ◽  
Long Range Transport ◽  
Naval Research ◽  
Chemical Transport Model ◽  
Northeast Pacific ◽  
Range Transport

Abstract. Interannual variations in background tropospheric trace gases (such as carbon monoxide, CO) are largely driven by variations in emissions (especially wildfires), transport pathways and tropospheric oxidizing capacity. Understanding this variability is essential to quantify the intercontinental contribution to US air quality. We investigate the interannual variability of long-range transport of Asian pollutants to the Northeast Pacific via measurements from the Mt. Bachelor Observatory (MBO: 43.98° N, 121.69° W; 2.7 km above sea level) and GEOS-Chem chemical transport model simulations in spring 2005 vs. the INTEX-B campaign during spring 2006. Measurements of CO at MBO were significantly enhanced during spring 2005 relative to the same time in 2006 (the INTEX-B study period); a monthly mean decline in CO of 41 ppbv was observed between April 2005 and April 2006. Meteorological indices show that long-range transport of CO from the heavily industrialized region of East Asia was significantly greater in 2005 than in 2006. In addition, spring 2005 was an anomalously strong biomass burning season in Southeast Asia. Data presented by Yurganov et al. (2008) using MOPITT satellite retrievals from this area reveal an average CO burden anomaly (referenced to March 2000–February 2002 mean values) between October 2004 through April 2005 of 2.6 Tg CO vs. 0.6 Tg CO for the same period a year later. The Naval Research Laboratory's global aerosol transport model shows that emissions from these fires were efficiently transported to MBO throughout April 2005. Asian dust transport, however, was substantially greater in 2006 than 2005, particularly in May. Monthly mean aerosol light scattering coefficient at 532 nm (σsp) at MBO more than doubled from 2.7 Mm−1 in May 2005 to 6.2 Mm−1 in May 2006. We also evaluate CO interannual variability throughout the western US via Earth System Research Laboratory ground site data and throughout the Northern Hemisphere via MOPITT and TES satellite observations. Both in the Northeast Pacific and on larger scales, we reveal a significant decrease (from 2–21%) in springtime maximum CO between 2005 and 2006, evident in all platforms and the GEOS-Chem model. We attribute this to (a) anomalously strong biomass burning in Southeast Asia during winter 2004 through spring 2005, and (b) the transport pattern in 2006 which limited the inflow of Asian pollution to the lower free troposphere over western North America.

Application of a long range transport model to a mount Etna plume

1984 ◽  
Vol 47 (4) ◽  
pp. 1097-1106 ◽  
Author(s):  
D. Martin ◽  
J. P. Granier ◽  
M. Imbard ◽  
B. Strauss
Keyword(s):  
Long Range ◽  
Transport Model ◽  
Mount Etna ◽  
Long Range Transport ◽  
Range Transport

A long-range transport model for ammonia and ammonium for Europe

1987 ◽  
Vol 21 (10) ◽  
pp. 2099-2119 ◽  
Author(s):  
Willem A.H. Asman ◽  
Anton J. Janssen
Keyword(s):  
Long Range ◽  
Transport Model ◽  
Long Range Transport ◽  
Range Transport

scholarly journals Future climatic drivers and their effect on PM<sub>10</sub> components in Europe and the Mediterranean Sea

2019 ◽  
Vol 19 (7) ◽  
pp. 4459-4484 ◽  
Author(s):  
Arineh Cholakian ◽  
Augustin Colette ◽  
Isabelle Coll ◽  
Giancarlo Ciarelli ◽  
Matthias Beekmann
Keyword(s):  
Long Range ◽  
Transport Model ◽  
Regional Climate ◽  
Mediterranean Area ◽  
Long Range Transport ◽  
Anthropogenic Emissions ◽  
Impact Study ◽  
Chemistry Transport Model ◽  
Range Transport ◽  
The Mediterranean

Abstract. Multiple CMIP5 (Coupled Model Intercomparison Project phase 5) future scenarios run with the CHIMERE chemistry transport model (CTM) are compared to historic simulations in order to study some of the drivers governing air pollution. Here, the focus is on regional climate, anthropogenic emissions and long-range transport. Two major subdomains are explored – the European region and the Mediterranean Basin – with both areas showing high sensitivity to climate change. The Mediterranean area is explored in the context of the ChArMEx (the Chemistry Aerosol Mediterranean Experiment) project, which examines the current and future meteorological and chemical conditions of the Mediterranean area. This climate impact study covers the period from 2031 to 2100 and considers possible future scenarios in comparison with 1976 to 2005 historic simulations using three Representative Concentration Pathways (RCPs; RCP2.6, RCP4.5 and RCP8.5). A detailed analysis of total PM10 (particulate matter with a diameter smaller that 10 µm) concentrations is carried out, including the evolution of PM10 and changes to its composition. The individual effects of meteorological conditions on PM10 components are explored in these scenarios in an effort to pinpoint the meteorological parameter(s) governing each component. The anthropogenic emission impact study covers the period from 2046 to 2055 using current legislation (CLE) and maximum feasible reduction (MFR) anthropogenic emissions for the year 2050 compared with historic simulations covering the period from 1996 to 2005 and utilizing CLE2010 emissions data. Long-range transport is explored by changing the boundary conditions in the chemistry transport model over the same period as the emission impact studies. Finally, a cumulative effect analysis of these drivers is performed, and the impact of each driver on PM10 and its components is estimated. The results show that regional climate change causes a decrease in the PM10 concentrations in our scenarios (in both the European and Mediterranean subdomains), as a result of a decrease in nitrate, sulfate, ammonium and dust atmospheric concentrations in most scenarios. On the contrary, BSOA (biogenic secondary organic aerosol) displays an important increase in all scenarios, showing more pronounced concentrations for the European subdomain compared with the Mediterranean region. Regarding the relationship of different meteorological parameters to concentrations of different species, nitrate and BSOA show a strong temperature dependence, whereas sulfate is most strongly correlated with relative humidity. The temperature-dependent behavior of BSOA changes when looking at the Mediterranean subdomain, where it displays more dependence on wind speed, due to the transported nature of BSOA existing in this subdomain. A cumulative look at all drivers shows that anthropogenic emission changes overshadow changes caused by climate and long-range transport for both of the subdomains explored, with the exception of dust particles for which long-range transport changes are more influential, especially in the Mediterranean Basin. For certain species (such as sulfates and BSOA), in most of the subdomains explored, the changes caused by anthropogenic emissions are (to a certain extent) reduced by the boundary conditions and regional climate changes.

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