Global wet reduced nitrogen deposition derived from combining satellite measurements with output from a chemistry transport model

<p>Ammonia (NH3) has received a lot of attention nowadays due to its major implications for the population and the environment. Global sources of ammonia include wild animals, ammonia-containing water areas, traffic, sewage systems, humans, biomass burning (mainly from dung fires and domestic coal combustion), volcanic eruptions and agriculture. In the present study, we used 10 years (2008&#8211;2017) of satellite measurements of ammonia retrieved from the Infrared Atmospheric Sounding Interferometer (IASI) to calculate surface emissions. In contrast to other methods, we first used a sophisticated Inverse Distance Weighting (IDW) interpolation algorithm to define a grid of column-integrated ammonia concentrations globally. In a hypothetical box model, emissions are given as a function of the mass of ammonia in each atmospheric box (in molecules cm-3) divided by the lifetime of ammonia in the box (in seconds) based on all the potential removal processes that affect atmospheric ammonia. Instead of considering the lifetime of ammonia as a constant value, such as in the relevant literature, we used calculated gridded lifetimes from a Chemistry Transport Model (CTM). The estimated emissions were then imported in a CTM and were simulated for the same 10&#8211;year period. To verify the improvement of the calculated emissions of ammonia, we evaluated the modelled surface concentrations against ground&#8211;based measurements from different monitoring stations. The same comparison was performed for the most recent state&#8211;of&#8211;the&#8211;art emission dataset for ammonia.</p>

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Dynamically controlled ozone decline in the tropical mid-stratosphere observed by SCIAMACHY

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-767-2019 ◽

2019 ◽

Vol 19 (2) ◽

pp. 767-783 ◽

Cited By ~ 7

Author(s):

Evgenia Galytska ◽

Alexey Rozanov ◽

Martyn P. Chipperfield ◽

Sandip. S. Dhomse ◽

Mark Weber ◽

...

Keyword(s):

Residence Time ◽

Transport Model ◽

Stratospheric Ozone ◽

Satellite Measurements ◽

Linear Change ◽

Chemistry Transport Model ◽

Negative Change ◽

Time Period ◽

Scanning Imaging ◽

Odd Nitrogen

Abstract. Despite the recently reported beginning of a recovery in global stratospheric ozone (O3), an unexpected O3 decline in the tropical mid-stratosphere (around 30–35 km altitude) was observed in satellite measurements during the first decade of the 21st century. We use SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) measurements for the period 2004–2012 to confirm the significant O3 decline. The SCIAMACHY observations show that the decrease in O3 is accompanied by an increase in NO2. To reveal the causes of these observed O3 and NO2 changes, we performed simulations with the TOMCAT 3-D chemistry-transport model (CTM) using different chemical and dynamical forcings. For the 2004–2012 time period, the TOMCAT simulations reproduce the SCIAMACHY-observed O3 decrease and NO2 increase in the tropical mid-stratosphere. The simulations suggest that the positive changes in NO2 (around 7 % decade−1) are due to similar positive changes in reactive odd nitrogen (NOy), which are a result of a longer residence time of the source gas N2O and increased production via N2O + O(1D). The model simulations show a negative change of 10 % decade−1 in N2O that is most likely due to variations in the deep branch of the Brewer–Dobson Circulation (BDC). Interestingly, modelled annual mean “age of air” (AoA) does not show any significant changes in transport in the tropical mid-stratosphere during 2004–2012. However, further analysis of model results demonstrates significant seasonal variations. During the autumn months (September–October) there are positive AoA changes that imply transport slowdown and a longer residence time of N2O allowing for more conversion to NOy, which enhances O3 loss. During winter months (January–February) there are negative AoA changes, indicating faster N2O transport and less NOy production. Although the variations in AoA over a year result in a statistically insignificant linear change, non-linearities in the chemistry–transport interactions lead to a statistically significant negative N2O change.

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The influence of biogenic emissions on upper-tropospheric methanol as revealed from space

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-9183-2007 ◽

2007 ◽

Vol 7 (3) ◽

pp. 9183-9202 ◽

Cited By ~ 2

Author(s):

G. Dufour ◽

S. Szopa ◽

D. A. Hauglustaine ◽

C. D. Boone ◽

C. P. Rinsland ◽

...

Keyword(s):

Fourier Transform ◽

Transport Model ◽

State Of The Art ◽

Tropospheric Chemistry ◽

Biogenic Emissions ◽

Fourier Transform Spectrometer ◽

Satellite Measurements ◽

Chemistry Transport Model ◽

Organic Species ◽

Global Space

Abstract. The distribution and budget of oxygenated organic compounds in the atmosphere and their impact on tropospheric chemistry are still poorly constrained. Near-global space-borne measurements of seasonally resolved upper tropospheric profiles of methanol by the ACE Fourier transform spectrometer provide a unique opportunity to evaluate our understanding of this important oxygenated organic species. The comparison with distributions simulated by a state-of-the-art chemistry transport model shows fair agreement during the March 2004 to August 2005 period with about 50% of the measurements reproduced by the model within 50%. However, in the northern hemisphere and during summertime, the satellite measurements reveal that the emissions from the continental biosphere lead to upper-tropospheric methanol concentrations significantly higher than expected.

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Dynamically controlled ozone decline in the tropical mid-stratosphere observed by SCIAMACHY

10.5194/acp-2018-746 ◽

2018 ◽

Author(s):

Evgenia Galytska ◽

Alexey Rozanov ◽

Martyn P. Chipperfield ◽

Sandip S. Dhomse ◽

Mark Weber ◽

...

Keyword(s):

Residence Time ◽

Transport Model ◽

Stratospheric Ozone ◽

Satellite Measurements ◽

Chemistry Transport Model ◽

Deep Branch ◽

Negative Change ◽

Time Period ◽

Scanning Imaging ◽

Odd Nitrogen

Abstract. Despite the recently reported beginning of a recovery in global stratospheric ozone (O3), an unexpected O3 decline in the tropical mid-stratosphere (around 30–35 km altitude) was observed in satellite measurements during the first decade of the 21st century. We use SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) measurements for the period 2004–2012 to confirm the significant O3 decline. The SCIAMACHY observations also show that the decrease in O3 is accompanied by an increase in NO2. To reveal the causes of these observed O3 and NO2 changes, we performed simulations with the TOMCAT 3D Chemistry-Transport Model (CTM) using different chemical and dynamical forcings. For the 2004–2012 time period, the TOMCAT simulations reproduce the SCIAMACHY-observed O3 decrease and NO2 increase in the tropical mid-stratosphere. The simulations suggest that the positive changes in NO2 (around 7 % per decade) are due to similar positive changes in reactive odd nitrogen (NOy), which are a result of a longer residence time of the source gas N2O and increased production via N2O + O(1D). The model simulations show a negative change of 10 % per decade in N2O that is most likely due to variations in the deep branch of the Brewer-Dobson Circulation (BDC). Interestingly, modelled annual mean age-of-air (AoA) does not show any significant changes in the transport in the tropical mid-stratosphere during 2004–2012. However, further analysis of model results demonstrate significant seasonal variations. During the autumn months (September–October) there are positive AoA changes, that imply transport slowdown and a longer residence time of N2O allowing larger conversion to NOy which enhances O3 loss. During winter months (January–February) there are negative AoA changes, indicating faster N2O transport and less NOy production. Although the changes in AoA cancel out when averaging over the year, non-linearities in the chemistry-transport interactions mean that the net negative N2O change remains.

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Tropospheric column ozone: matching individual profiles from Aura OMI and TES with a chemistry-transport model

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-10441-2012 ◽

2012 ◽

Vol 12 (21) ◽

pp. 10441-10452 ◽

Cited By ~ 6

Author(s):

Q. Tang ◽

M. J. Prather

Keyword(s):

Large Scale ◽

Cross Validation ◽

Transport Model ◽

A Priori ◽

Ozone Monitoring Instrument ◽

Satellite Measurements ◽

Chemistry Transport Model ◽

Transfer Standard ◽

Column Ozone ◽

Individual Profiles

Abstract. Of all satellite measurements of ozone, only two instruments have coincident, spatially overlapping measurements to allow direct comparison of tropospheric column ozone (TCO): the Ozone Monitoring Instrument (OMI) and the Tropospheric Emission Spectrometer (TES) on the NASA Aura spacecraft. For two years (2005–2006), we collect all observations between 60° S and 60° N from nadir (~65 000 from OMI and TES) and cross-track swaths (~30 000 000 from OMI) and compare with a chemistry-transport model (CTM) simulating each observation with corresponding spatial and temporal coincidence. High-frequency TCO variations are indicative of stratospheric intrusions of ozone-rich air, and the individual, level 2 data provide access to these short-lived phenomena. Although we can identify some seasonal and large-scale biases in the model, the CTM as a transfer standard identifies weaknesses in the observations and further helps quantify the measurement noise of individual profiles. The relatively noise-free CTM bridges these two satellite measurements and improves their cross-validation to better precision than a simple direct comparison. Previous validation studies of TES TCO versus ozonesondes found a bias of about +4 Dobson Units (DU) for large regions. The three-way comparison and the CTM transfer method that use a far greater number of coincidences, indicate that monthly zonal mean OMI-TES TCO biases fall within 5–10%, and thus quantifies the zonal mean OMI TCO bias at a few DU. For small regions (i.e., 5 × 5°), however, the monthly mean OMI-TES differences can exceed ±10 DU at many places (e.g., tropics for the direct OMI-TES comparison) due to different tropospheric sensitivities of the two instruments at these locations. Partly removing the influence of different sensitivities by applying the CTM as the transfer standard, the OMI-TES differences generally decrease, especially over the tropics. In addition, the CTM-TES comparison split into day versus night observations shows no apparent bias in TES at very low levels, ±1 DU. These OMI-TES-CTM comparisons highlight the importance of the a priori ozone profiles that went into each satellite retrieval, including a false agreement due to CTM-a priori similarity, and the importance of including the vertical information (i.e., averaging kernel) in the retrieval products. This study also highlights the advantages of overlapping measurements in terms of cross-validation and the application of a model as the transfer standard.

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Atmospheric nitrogen deposition to terrestrial ecosystems across Germany

10.5194/bg-2017-491 ◽

2017 ◽

Cited By ~ 7

Author(s):

Martijn Schaap ◽

Sabine Banzhaf ◽

Thomas Scheuschner ◽

Markus Geupel ◽

Carlijn Hendriks ◽

...

Keyword(s):

Nitrogen Deposition ◽

Wet Deposition ◽

Transport Model ◽

Terrestrial Ecosystems ◽

Atmospheric Nitrogen ◽

Integrated Monitoring ◽

Chemistry Transport Model ◽

Deposition Fluxes ◽

Empirical Modelling ◽

Quantitative Estimates

Abstract. Biodiversity is strongly affected by the deposition of nitrogen and sulfur on terrestrial ecosystems. In this paper we present new quantitative estimates of the deposition of atmospheric nitrogen to ecosystems across Germany. The methodology combines prognostic and empirical modelling to establish wet deposition fluxes and land use dependent dry and occult deposition fluxes. On average, the nitrogen deposition in Germany was estimated to be 1057 eq ha−1 yr−1. The deposition maps show considerable variability across the German territory with highest deposition on forest ecosystems in or near the main agricultural and industrial areas. The accumulated deposition over Germany of this study is systematically lower (27 %) than provided in earlier studies. The main reasons are an improved wet deposition estimation and the consolidation of improved process descriptions in the LOTOS-EUROS chemistry transport model. The presented deposition estimates show a better agreement with results obtained by integrated monitoring and deposition modelling by EMEP than the earlier results. Through comparison of the new deposition distributions with critical load maps it is estimated that 70 % of the ecosystems in Germany receive too much nitrogen.

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Tropospheric column ozone: matching individual profiles from Aura OMI and TES with a chemistry-transport model

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-16061-2012 ◽

2012 ◽

Vol 12 (6) ◽

pp. 16061-16083

Author(s):

Q. Tang ◽

M. J. Prather

Keyword(s):

Large Scale ◽

Cross Validation ◽

Transport Model ◽

A Priori ◽

Ozone Monitoring Instrument ◽

Satellite Measurements ◽

Chemistry Transport Model ◽

Transfer Standard ◽

Column Ozone ◽

Individual Profiles

Abstract. Of all satellite measurements of ozone, only two instruments have coincident, spatially overlapping measurements to allow direct comparison of tropospheric column ozone (TCO): the Ozone Monitoring Instrument (OMI) and Tropospheric Emission Spectrometer (TES) on the NASA Aura spacecraft. For two years (2005–2006), we collect all observations between 60° S and 60° N from nadir (~65 000 from OMI and TES) and cross-track swaths (~30 000 000 from OMI) and compare with a chemistry-transport model (CTM) simulating each observation with corresponding spatial and temporal coincidence. High-frequency TCO variations are indicative of stratospheric intrusions of ozone-rich air, and the individual, level 2 data provide access to these short-lived phenomena. Although we can identify some seasonal and large-scale biases in the model, the CTM as a transfer standard identifies weaknesses in the observations and further helps quantify the measurement noise of individual profiles. The relatively noise-free CTM bridges these two satellite measurements and improves their cross-validation to better precision than a simple direct comparison. Previous validation studies of TES TCO versus ozonesondes found a bias of about +4 Dobson Units (DU) for large regions. The three-way comparison, with a far greater number of coincidences, indicates that monthly mean OMI-TES TCO biases fall within a few percent, and thus quantifies the OMI TCO bias at a few DU. For small regions (i.e., 5 × 5°), however, the monthly mean OMI-TES differences can exceed &pm;10 DU at many places (e.g., tropics) due to different tropospheric sensitivities of the two instruments at these locations. In addition, the CTM-TES comparison split into day versus night observations shows no apparent bias in TES at very low levels, &pm;1 DU. These OMI-TES-CTM comparisons highlighted the importance of the a priori ozone profiles that went into each satellite retrieval, including a false agreement due to CTM-a priori similarity. This study highlights the advantages of overlapping measurements in terms of cross-validation and the application of a model as a transfer standard.

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Variability of springtime transpacific pollution transport during 2000–2006: the INTEX-B mission in the context of previous years

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-1345-2010 ◽

2010 ◽

Vol 10 (3) ◽

pp. 1345-1359 ◽

Cited By ~ 16

Author(s):

G. G. Pfister ◽

L. K. Emmons ◽

D. P. Edwards ◽

A. Arellano ◽

T. Campos ◽

...

Keyword(s):

Transport Model ◽

Pollution Transport ◽

Chemistry Transport Model ◽

Pollution Levels ◽

Annual Variability ◽

Source Regions ◽

Time Period ◽

The Pacific ◽

The Us ◽

Transport Experiment

Abstract. We analyze the transport of pollution across the Pacific during the NASA INTEX-B (Intercontinental Chemical Transport Experiment Part B) campaign in spring 2006 and examine how this year compares to the time period for 2000 through 2006. In addition to aircraft measurements of carbon monoxide (CO) collected during INTEX-B, we include in this study multi-year satellite retrievals of CO from the Measurements of Pollution in the Troposphere (MOPITT) instrument and simulations from the chemistry transport model MOZART-4. Model tracers are used to examine the contributions of different source regions and source types to pollution levels over the Pacific. Additional modeling studies are performed to separate the impacts of inter-annual variability in meteorology and dynamics from changes in source strength. Interannual variability in the tropospheric CO burden over the Pacific and the US as estimated from the MOPITT data range up to 7% and a somewhat smaller estimate (5%) is derived from the model. When keeping the emissions in the model constant between years, the year-to-year changes are reduced (2%), but show that in addition to changes in emissions, variable meteorological conditions also impact transpacific pollution transport. We estimate that about 1/3 of the variability in the tropospheric CO loading over the contiguous US is explained by changes in emissions and about 2/3 by changes in meteorology and transport. Biomass burning sources are found to be a larger driver for inter-annual variability in the CO loading compared to fossil and biofuel sources or photochemical CO production even though their absolute contributions are smaller. Source contribution analysis shows that the aircraft sampling during INTEX-B was fairly representative of the larger scale region, but with a slight bias towards higher influence from Asian contributions.

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The On-Line Integrated Mesoscale Chemistry Model BOLCHEM

Atmosphere ◽

10.3390/atmos12020192 ◽

2021 ◽

Vol 12 (2) ◽

pp. 192

Author(s):

Rita Cesari ◽

Tony Christian Landi ◽

Massimo D’Isidoro ◽

Mihaela Mircea ◽

Felicita Russo ◽

...

Keyword(s):

Correlation Coefficient ◽

Transport Model ◽

Horizontal Resolution ◽

Integration Step ◽

Chemistry Transport Model ◽

European Environmental Agency ◽

On Line ◽

One Year ◽

Pm2.5 And Pm10 ◽

Monitoring Service

This work presents the on-line coupled meteorology–chemistry transport model BOLCHEM, based on the hydrostatic meteorological BOLAM model, the gas chemistry module SAPRC90, and the aerosol dynamic module AERO3. It includes parameterizations to describe natural source emissions, dry and wet removal processes, as well as the transport and dispersion of air pollutants. The equations for different processes are solved on the same grid during the same integration step, by means of a time-split scheme. This paper describes the model and its performance at horizontal resolution of 0.2∘× 0.2∘ over Europe and 0.1∘× 0.1∘ in a nested configuration over Italy, for one year run (December 2009–November 2010). The model has been evaluated against the AIRBASE data of the European Environmental Agency. The basic statistics for higher resolution simulations of O3, NO2 and particulate matter concentrations (PM2.5 and PM10) have been compared with those from Copernicus Atmosphere Monitoring Service (CAMS) ensemble median. In summer, for O3 we found a correlation coefficient R of 0.72 and mean bias of 2.15 over European domain and a correlation coefficient R of 0.67 and mean bias of 2.36 over Italian domain. PM10 and PM2.5 are better reproduced in the winter, the latter with a correlation coefficient R of 0.66 and the mean bias MB of 0.35 over Italian domain.

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