Review of the manuscript “Biomass-burning and urban emission impacts in the Andes Cordillera region based on in-situ measurements from the Chacaltaya observatory, Bolivia (5240 m a.s.l.)” by Chauvigné Aurélien et al.

Although the characteristics of biomass burning events and the ambient ecosystem determine emitted smoke composition, the conditions that modulate the partitioning of black carbon (BC) and brown carbon (BrC) formation are not well understood, nor are the spatial or temporal frequency of factors driving smoke particle evolution, such as hydration, coagulation, and oxidation, all of which impact smoke radiative forcing. In situ data from surface observation sites and aircraft field campaigns offer deep insight into the optical, chemical, and microphysical traits of biomass burning (BB) smoke aerosols, such as single scattering albedo (SSA) and size distribution, but cannot by themselves provide robust statistical characterization of both emitted and evolved particles. Data from the NASA Earth Observing System’s Multi-Angle Imaging SpectroRadiometer (MISR) instrument can provide at least a partial picture of BB particle properties and their evolution downwind, once properly validated. Here we use in situ data from the joint NOAA/NASA 2019 Fire Influence on Regional to Global Environments Experiment-Air Quality (FIREX-AQ) field campaign to assess the strengths and limitations of MISR-derived constraints on particle size, shape, light-absorption, and its spectral slope, as well as plume height and associated wind vectors. Based on the satellite observations, we also offer inferences about aging mechanisms effecting downwind particle evolution, such as gravitational settling, oxidation, secondary particle formation, and the combination of particle aggregation and condensational growth. This work builds upon our previous study, adding confidence to our interpretation of the remote-sensing data based on an expanded suite of in situ measurements for validation. The satellite and in situ measurements offer similar characterizations of particle property evolution as a function of smoke age for the 06 August Williams Flats Fire, and most of the key differences in particle size and absorption can be attributed to differences in sampling and changes in the plume geometry between sampling times. Whereas the aircraft data provide validation for the MISR retrievals, the satellite data offer a spatially continuous mapping of particle properties over the plume, which helps identify trends in particle property downwind evolution that are ambiguous in the sparsely sampled aircraft transects. The MISR data record is more than two decades long, offering future opportunities to study regional wildfire plume behavior statistically, where aircraft data are limited or entirely lacking.

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Aerosol classification by airborne high spectral resolution lidar observations

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-2487-2013 ◽

2013 ◽

Vol 13 (5) ◽

pp. 2487-2505 ◽

Cited By ~ 124

Author(s):

S. Groß ◽

M. Esselborn ◽

B. Weinzierl ◽

M. Wirth ◽

A. Fix ◽

...

Keyword(s):

Biomass Burning ◽

Spectral Resolution ◽

Classification Scheme ◽

In Situ Measurements ◽

High Spectral Resolution ◽

Data Set ◽

Aerosol Classification ◽

High Spectral Resolution Lidar ◽

Aerosol Types

Abstract. During four aircraft field experiments with the DLR research aircraft Falcon in 1998 (LACE), 2006 (SAMUM-1) and 2008 (SAMUM-2 and EUCAARI), airborne High Spectral Resolution Lidar (HSRL) and in situ measurements of aerosol microphysical and optical properties were performed. Altogether, the properties of six different aerosol types and aerosol mixtures – Saharan mineral dust, Saharan dust mixtures, Canadian biomass burning aerosol, African biomass burning mixture, anthropogenic pollution aerosol, and marine aerosol have been studied. On the basis of this extensive HSRL data set, we present an aerosol classification scheme which is also capable to identify mixtures of different aerosol types. We calculated mixing lines that allowed us to determine the contributing aerosol types. The aerosol classification scheme was supported by backward trajectory analysis and validated with in-situ measurements. Our results demonstrate that the developed aerosol mask is capable to identify complex stratifications with different aerosol types throughout the atmosphere.

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Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-815-2007 ◽

2007 ◽

Vol 7 (3) ◽

pp. 815-838 ◽

Cited By ~ 136

Author(s):

B. Sauvage ◽

R. V. Martin ◽

A. van Donkelaar ◽

X. Liu ◽

K. Chance ◽

...

Keyword(s):

Biomass Burning ◽

Tropospheric Ozone ◽

In Situ Measurements ◽

Model Bias ◽

Top Down ◽

Upper Troposphere ◽

In Situ Observations ◽

Tropospheric O3 ◽

Bias Versus

Abstract. We use a global chemical transport model (GEOS-Chem) to evaluate the consistency of satellite measurements of lightning flashes and ozone precursors with in situ measurements of tropical tropospheric ozone. The measurements are tropospheric O3, NO2, and HCHO columns from the GOME satellite instrument, lightning flashes from the OTD and LIS satellite instruments, profiles of O3, CO, and relative humidity from the MOZAIC aircraft program, and profiles of O3 from the SHADOZ ozonesonde network. We interpret these multiple data sources with our model to better understand what controls tropical tropospheric ozone. Tropical tropospheric ozone is mainly affected by lightning NOx and convection in the upper troposphere and by surface emissions in the lower troposphere. Scaling the spatial distribution of lightning in the model to the observed flashes improves the simulation of O3 in the upper troposphere by 5–20 ppbv versus in situ observations and by 1–4 Dobson Units versus GOME retrievals of tropospheric O3 columns. A lightning source strength of 6±2 Tg N/yr best represents in situ observations from aircraft and ozonesonde. Tropospheric NO2 and HCHO columns from GOME are applied to provide top-down constraints on emission inventories of NOx (biomass burning and soils) and VOCs (biomass burning). The top-down biomass burning inventory is larger than the bottom-up inventory by a factor of 2 for HCHO and alkenes, and by a factor of 2.6 for NOx over northern equatorial Africa. These emissions increase lower tropospheric O3 by 5–20 ppbv, improving the simulation versus aircraft observations, and by 4 Dobson Units versus GOME observations of tropospheric O3 columns. Emission factors in the a posteriori inventory are more consistent with a recent compilation from in situ measurements. The ozone simulation using two different dynamical schemes (GEOS-3 and GEOS-4) is evaluated versus observations; GEOS-4 better represents O3 observations by 5–15 ppbv, reflecting enhanced convective detrainment in the upper troposphere. Heterogeneous uptake of HNO3 on aerosols reduces simulated O3 by 5–7 ppbv, reducing a model bias versus in situ observations over and downwind of deserts. Exclusion of HO2 uptake on aerosols increases O3 by 5 ppbv in biomass burning regions, reducing a model bias versus MOZAIC aircraft measurements.

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Multiscale observations of NH3 around Toronto, Canada

10.5194/egusphere-egu2020-10486 ◽

2020 ◽

Author(s):

Shoma Yamanouchi ◽

Camille Viatte ◽

Kimberly Strong ◽

Dylan B. A. Jones ◽

Cathy Clerbaux ◽

...

Keyword(s):

Case Studies ◽

Biomass Burning ◽

Grid Point ◽

Fine Particulate Matter ◽

Regional Scale ◽

Model Performance ◽

In Situ Measurements ◽

Coefficient Of Determination ◽

Predictive Capacity

<div> <div> <div> <p>Ammonia (NH<sub>3</sub>) is a major source of nitrates in the atmosphere, and a major source of fine particulate matter. As such, there have been increasing efforts to monitor NH<sub>3</sub>. This study examines long-term measurements of NH<sub>3</sub> around Toronto, Canada, derived from three multiscale datasets: 16 years of total column measurements using ground-based Fourier transform infrared (FTIR) spectroscopy, three years of surface in-situ measurements, and ten years of total columns from the Infrared Atmospheric Sounding Interferometer (IASI) sensor onboard the Metop satellites. These datasets were used to quantify NH<sub>3</sub> temporal variabilities (trends, inter-annual, seasonal) over Toronto to assess the observational footprint of the FTIR measurements, and two case studies of pollution events due to transport of biomass burning plumes.</p> <p>All three timeseries showed increasing trends in NH<sub>3</sub> over Toronto: 3.34 &#177; 0.44 %/year from 2002 to 2018 in the FTIR columns, 8.88 &#177; 2.49 %/year from 2013 to 2017 in the surface in-situ data, and 8.78 &#177; 0.84 %/year from 2008 to 2018 in the IASI columns. To assess the observational footprint of the FTIR NH<sub>3</sub> columns, correlations between the datasets were examined. The best correlation between FTIR and IASI was found for coincidence criterion of &#8804; 50 km and &#8804; 20 minutes, with r = 0.66 and a slope of 0.988 &#177; 0.058. The FTIR column and in-situ measurements were standardized and correlated, with 24-day averages and monthly averages yielding correlation coefficients of r = 0.72 and r = 0.75, respectively.<br>FTIR and IASI were also compared against the GEOS-Chem model, run at 2&#176; by 2.5&#176; resolution, to assess model performance and investigate correlation of the model output with local column measurements (FTIR) and measurements on a regional scale (IASI). Comparisons on a regional scale (domain spanning from 35&#176;N to 53&#176;N, and 93.75&#176;W to 63.75&#176;W) resulted in r = 0.62, and thus a coefficient of determination, which is indicative of the predictive capacity of the model, of r<sup>2</sup> = 0.38, but comparing a single model grid point against the FTIR resulted in a poorer correlation, with r<sup>2</sup> = 0.26, indicating that a finer spatial resolution is needed to adequately model the variability of NH<sub>3</sub>. This study also examines two case studies of NH<sub>3</sub> enhancements due to biomass burning plumes, in August 2014 and May 2016. In these events, enhancements in both the total columns and surface NH3, were observed.</p> </div> </div> </div>

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Remote sensed and in situ constraints on processes affecting tropical tropospheric ozone

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-6-11465-2006 ◽

2006 ◽

Vol 6 (6) ◽

pp. 11465-11520 ◽

Cited By ~ 1

Author(s):

B. Sauvage ◽

R. V. Martin ◽

A. van Donkelaar ◽

X. Liu ◽

K. Chance ◽

...

Keyword(s):

Biomass Burning ◽

Tropospheric Ozone ◽

Transport Model ◽

Lower Troposphere ◽

In Situ Measurements ◽

Top Down ◽

Upper Troposphere ◽

In Situ Observations ◽

Tropospheric O3

Abstract. We use a global chemical transport model (GEOS-Chem) to evaluate the consistency of satellite measurements of lightning flashes and ozone precursors with in situ measurements of tropical tropospheric ozone. The measurements are tropospheric O3, NO2, and HCHO columns from the GOME satellite instrument, lightning flashes from the OTD and LIS instruments, profiles of O3, CO, and relative humidity from the MOZAIC aircraft program, and profiles of O3 from the SHADOZ ozonesonde network. We interpret these multiple data sources with our model to better understand what controls tropical tropospheric ozone. Tropical tropospheric ozone is mainly affected by lightning and convection in the upper troposphere and by surface emissions in the lower troposphere. Scaling the spatial distribution of lightning in the model to the observed flash counts improves the simulation of O3 in the upper troposphere by 5–20 ppbv versus in situ observations and by 1–4 Dobson Units versus GOME retrievals of tropospheric O3 columns. A lightning source strength of 5±2 Tg N/yr best represents in situ observations from aircraft and ozonesonde. Tropospheric NO2 and HCHO columns from GOME are applied to provide top-down constraints on emission inventories of NOx (biomass burning and soils) and VOCs (biomass burning). The top-down biomass burning inventory is larger by a factor of 2 for HCHO and alkenes, and by 2.6 for NOx over northern equatorial Africa. These emissions increase lower tropospheric O3 by 5–20 ppbv, improving the simulation versus aircraft observations, and by 4 Dobson Units versus GOME observations of tropospheric O3 columns. Emission factors in the a posteriori inventory are more consistent with a recent compilation from in situ measurements. The ozone simulation using two different dynamical schemes (GEOS-3 and GEOS-4) is evaluated versus observations; GEOS-4 better represents O3 observations by 5–15 ppbv due to enhanced convective detrainment in the upper troposphere. Heterogeneous uptake of HNO3 on aerosols reduces simulated O3 by 5–7 ppbv, reducing a model bias versus in situ observations over and downwind of deserts. Exclusion of HO2 uptake on aerosols improves O3 by 5 ppbv in biomass burning regions.

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Decadal trends in global CO emissions as seen by MOPITT

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-14505-2015 ◽

2015 ◽

Vol 15 (10) ◽

pp. 14505-14547 ◽

Cited By ~ 4

Author(s):

Y. Yin ◽

F. Chevallier ◽

P. Ciais ◽

G. Broquet ◽

A. Fortems-Cheiney ◽

...

Keyword(s):

Biomass Burning ◽

Chemical Oxidation ◽

In Situ Measurements ◽

Negative Trend ◽

Emission Inventories ◽

Co Concentration ◽

Co Emission ◽

Co Concentrations ◽

Atmospheric Inversion

Abstract. Negative trends of carbon monoxide (CO) concentrations are observed in the recent decade by both surface measurements and satellite retrievals over many regions, but they are not well explained by current emission inventories. Here, we attribute the observed CO concentration decline with an atmospheric inversion that simultaneously optimizes the two main CO sources (surface emissions and atmospheric hydrocarbon oxidations) and the main CO sink (atmospheric hydroxyl radical OH oxidation) by assimilating observations of CO and other chemically related tracers. Satellite CO column retrievals from Measurements of Pollution in the Troposphere (MOPITT), version 6, and surface in-situ measurements of methane and methyl-chloroform mole fractions are assimilated jointly for the period of 2002–2011. Compared to the prior simulation, the optimized CO concentrations show better agreement with independent surface in-situ measurements in terms of both distributions and trends. At the global scale, the atmospheric inversion primarily interprets the CO concentration decline as a decrease in the CO emissions, and finds noticeable trends neither in the chemical oxidation sources of CO, nor in the OH concentrations that regulate CO sinks. The latitudinal comparison of the model state with independent formaldehyde (CH2O) columns retrieved from the Ozone Measurement Instrument (OMI) confirms the absence of large-scale trends in the atmospheric source of CO. The global CO emission decreased by 17% during the decade, more than twice the negative trend estimated by emission inventories. The spatial distribution of the inferred decrease of CO emissions indicates contributions from both a decrease in fossil- and bio-fuel emissions over Europe, the USA and Asia, and from a decrease in biomass burning emissions in South America, Indonesia, Australia and Boreal regions. An emission decrease of 2% yr−1 is inferred in China, one of the main emitting regions, in contradiction with the bottom-up inventories that report an increase of 2% yr−1 during the study period. A large decrease in CO emission factors due to technology improvements would outweigh the increase of carbon fuel combustions and may explain the observed decrease. In Africa, instead of the negative trend (1% yr−1) reported by CO emission inventories mainly contributed by biomass burning, a positive trend (1.5% yr−1) is found by the atmospheric inversion, suggesting different trends between satellite-detected burned areas and CO emissions.

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Observations of glyoxal and formaldehyde as metrics for the anthropogenic impact on rural photochemistry

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-12-6049-2012 ◽

2012 ◽

Vol 12 (2) ◽

pp. 6049-6084 ◽

Cited By ~ 3

Author(s):

J. P. DiGangi ◽

S. B. Henry ◽

A. Kammrath ◽

E. S. Boyle ◽

L. Kaser ◽

...

Keyword(s):

Biomass Burning ◽

Pinus Ponderosa ◽

Model Comparison ◽

Organic Aerosol ◽

In Situ Measurements ◽

Rapid Changes ◽

Volatile Organic ◽

Satellite Retrievals ◽

Voc Mixtures

Abstract. We present simultaneous fast, in-situ measurements of formaldehyde and glyoxal from two rural campaigns, BEARPEX 2009 and BEACHON-ROCS, both located in Pinus Ponderosa forests with emissions dominated by biogenic volatile organic compounds (VOCs). Despite considerable variability in the formaldehyde and glyoxal concentrations, the ratio of glyoxal to formaldehyde, RGF, displayed a very regular diurnal cycle over nearly 2 weeks of measurements. The only deviations in RGF were toward higher values and were the result of a biomass burning event during BEARPEX 2009 and very fresh anthropogenic influence during BEACHON-ROCS. Other rapid changes in glyoxal and formaldehyde concentrations have hardly any affect on RGF and could reflect transitions between low and high NO regimes. The trend of increased RGF from both anthropogenic reactive VOC mixtures and biomass burning compared to biogenic reactive VOC mixtures is robust due to the short timescales over which the observed changes in RGF occurred. Satellite retrievals, which suggest higher RGF for biogenic areas, are in contrast to our observed trends. It remains important to address this discrepancy, especially in view of the importance of satellite retrievals and in-situ measurements for model comparison. In addition, we propose that RGF, together with the absolute concentrations of glyoxal and formaldehyde, represents a useful metric for biogenic or anthropogenic reactive VOC mixtures. In particular, RGF yields information about not simply the VOCs in an airmass, but the VOC processing that directly couples ozone and secondary organic aerosol production.

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Observations of glyoxal and formaldehyde as metrics for the anthropogenic impact on rural photochemistry

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-9529-2012 ◽

2012 ◽

Vol 12 (20) ◽

pp. 9529-9543 ◽

Cited By ~ 49

Author(s):

J. P. DiGangi ◽

S. B. Henry ◽

A. Kammrath ◽

E. S. Boyle ◽

L. Kaser ◽

...

Keyword(s):

Biomass Burning ◽

Pinus Ponderosa ◽

Model Comparison ◽

In Situ Measurements ◽

Anthropogenic Influence ◽

Rapid Changes ◽

Volatile Organic ◽

Satellite Retrievals ◽

Voc Mixtures

Abstract. We present simultaneous fast, in-situ measurements of formaldehyde and glyoxal from two rural campaigns, BEARPEX 2009 and BEACHON-ROCS, both located in Pinus Ponderosa forests with emissions dominated by biogenic volatile organic compounds (VOCs). Despite considerable variability in the formaldehyde and glyoxal concentrations, the ratio of glyoxal to formaldehyde, RGF, displayed a very regular diurnal cycle over nearly 2 weeks of measurements. The only deviations in RGF were toward higher values and were the result of a biomass burning event during BEARPEX 2009 and very fresh anthropogenic influence during BEACHON-ROCS. Other rapid changes in glyoxal and formaldehyde concentrations have hardly any affect on RGF and could reflect transitions between low and high NO regimes. The trend of increased RGF from both anthropogenic reactive VOC mixtures and biomass burning compared to biogenic reactive VOC mixtures is robust due to the short timescales over which the observed changes in RGF occurred. Satellite retrievals, which suggest higher RGF for biogenic areas, are in contrast to our observed trends. It remains important to address this discrepancy, especially in view of the importance of satellite retrievals and in situ measurements for model comparison. In addition, we propose that RGF represents a useful metric for biogenic or anthropogenic reactive VOC mixtures and, in combination with absolute concentrations of glyoxal and formaldehyde, furthermore represents a useful metric for the extent of anthropogenic influence on overall reactive VOC processing via NOx. In particular, RGF yields information about not simply the VOCs dominating reactivity in an airmass, but the VOC processing itself that is directly coupled to ozone and secondary organic aerosol production.

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Effect of biomass burning and regional background aerosols on CCN activity derived from airborne in-situ measurements

Atmospheric Environment ◽

10.1016/j.atmosenv.2010.08.044 ◽

2010 ◽

Vol 44 (39) ◽

pp. 5227-5236 ◽

Cited By ~ 9

Author(s):

Sihye Lee ◽

Young Sung Ghim ◽

Sang-Woo Kim ◽

Soon-Chang Yoon

Keyword(s):

Biomass Burning ◽

In Situ Measurements ◽

Regional Background ◽

Ccn Activity

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Investigation of Aerosol Climatology, Optical Characteristics and Variability over Egypt Based on Satellite Observations and In-Situ Measurements

Atmosphere ◽

10.3390/atmos11070714 ◽

2020 ◽

Vol 11 (7) ◽

pp. 714 ◽

Cited By ~ 1

Author(s):

Islam Abou El-Magd ◽

Naglaa Zanaty ◽

Elham M. Ali ◽

Hitoshi Irie ◽

Ahmed I. Abdelkader

Keyword(s):

Air Pollution ◽

Biomass Burning ◽

Daily Basis ◽

In Situ Measurements ◽

Western Desert ◽

Dust Particles ◽

Anthropogenic Aerosols ◽

Smoke Particles ◽

Modis Aod

Egypt experiences high rates of air pollution, which is a major threat to human health and the eco-environment and therefore needs to be tackled by defining major causes to hinder or mitigate their impacts. The major driving forces of air pollution are either of local and/or regional origin. In addition, seasonal aerosols may be natural, such as dust particles transported from the western desert, or anthropogenic aerosols which are transported from industrial areas and smoke particles from seasonal biomass burning. Monitoring the optical properties of aerosols and their pattern in the atmosphere on a daily basis requires a robust source of information and professional analytical tools. This research explored the potential of using time series of Moderate Resolution Imaging Spectroradiometer (MODIS) and Aerosol Robotic Network (AERONET) data to comprehensively investigate the aerosol optical depth (AOD) and variability for the period 2012–2018 on a daily basis. The data show that spring, summer and autumn seasons experienced the highest anomaly originating from regional and national sources. The high AOD in spring associated with a low Ångström exponent (AE) indicates the presence of coarse particles which naturally originate from desert dust or sea spray. In contrast, the high AE in summer and autumn demonstrated the dominance of fine anthropogenic aerosols such as smoke particles from local biomass burning. The observation of a high number of fire incidents over Egypt in October and November 2018, during the months of rice crop harvesting, showed that these incidents contribute to the presence of autumn aerosols across the country. In-situ measurements of Particulate Matter (PM10) from local stations from an environmental based network as well as the AERONET AOD were used to validate the MODIS AOD, providing a high correlation coefficient of r = 0.73.

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