Emissions of trace gases and aerosol particles due to vegetation burning in southern hemisphere Africa

Abstract. In situ observations of aerosol particles contained in cirrus crystals are presented and compared to interstitial aerosol size distributions (non-activated particles in between the cirrus crystals). The observations were conducted in cirrus clouds in the Southern and Northern Hemisphere mid-latitudes during the INCA project. The first campaign in March and April 2000 was performed from Punta Arenas, Chile (54° S) in pristine air. The second campaign in September and October 2000 was performed from Prestwick, Scotland (53° N) in the vicinity of the North Atlantic flight corridor. Size distribution measurements of crystal residuals (particles remaining after evaporation of the crystals) show that small aerosol particles (Dp < 0.1µm) dominate the number density of residuals. The crystal residual size distributions were significantly different in the two campaigns. On average the residual size distributions were shifted towards larger sizes in the Southern Hemisphere. For a given integral residual number density, the calculated particle volume was on average three times larger in the Southern Hemisphere. This may be of significance to the vertical redistribution of aerosol mass by clouds in the tropopause region. In both campaigns the mean residual size increased with increasing crystal number density. The observations of ambient aerosol particles were consistent with the expected higher pollution level in the Northern Hemisphere. The fraction of residual particles only contributes to approximately a percent or less of the total number of particles, which is the sum of the residual and interstitial particles.

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Year-long observations of chemical properties of organic aerosols and cloud residuals at the Zeppelin Observatory, Svalbard

10.5194/egusphere-egu21-13266 ◽

2021 ◽

Author(s):

Yvette Gramlich ◽

Sophie Haslett ◽

Karolina Siegel ◽

Gabriel Freitas ◽

Radovan Krejci ◽

...

Keyword(s):

Cloud Condensation Nuclei ◽

Aerosol Particles ◽

Trace Gases ◽

Chemical Properties ◽

Radiative Properties ◽

Cloud Formation ◽

The Arctic ◽

Arctic Clouds ◽

Clear Sky ◽

Air Inlet

The number of cloud seeds, e.g. cloud condensation nuclei (CCN) and ice nucleation particles (INP), in the pristine Arctic shows a large range throughout the year, thereby influencing the radiative properties of Arctic clouds. However, little is known about the chemical properties of CCN and INP in this region. This study aims to investigate the chemical properties of aerosol particles and trace gases that are of importance for cloud formation in the Arctic environment, with focus on the organic fraction.Over the course of one full year (fall 2019 until fall 2020), we deployed a filter-inlet for gases and aerosols coupled to a chemical ionization high-resolution time-of-flight mass spectrometer (FIGAERO-CIMS) using iodide as reagent ion at the Zeppelin Observatory in Svalbard (480 m a.s.l.), as part of the Ny-&#197;lesund Aerosol Cloud Experiment (NASCENT). The FIGAERO-CIMS is able to measure organic trace gases and aerosol particles semi-simultaneously. The instrument was connected to an inlet switching between a counterflow virtual impactor (CVI) inlet and a total air inlet. This setup allows to study the differences in chemical composition of organic aerosol particles and trace gases at molecular level that are involved in Arctic cloud formation compared to ambient non-activated aerosol.We observed organic signal above background in both gas and particle phase all year round. A comparison between the gas phase mass spectra of cloud-free and cloudy conditions shows lower signal for some organics inside the cloud, indicating that some trace gases are scavenged by cloud hydrometeors whilst others are not. In this presentation we will discuss the chemical characteristics of the gases exhibiting different behavior during clear sky and cloudy conditions, and the implications for partitioning of organic compounds between the gas, aerosol particle and cloud hydrometeor (droplet/ice) phase.

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The Atmospheric Component of Biogeochemical Cycles in the Amazon Basin

The Biogeochemistry of the Amazon Basin ◽

10.1093/oso/9780195114317.003.0006 ◽

2001 ◽

Author(s):

Paulo Artaxo

Keyword(s):

Land Use ◽

Tropical Forests ◽

Amazon Basin ◽

Aerosol Particles ◽

Trace Gases ◽

Biogeochemical Cycles ◽

Dry Season ◽

Earth System ◽

The Earth ◽

The Tropics

Tropical forests, with their high biological activity, have the potential to emit large amounts of trace gases and aerosol particles to the atmosphere. The accelerated development and land clearing that is occurring in large areas of the Amazon basin suggest that anthropogenic effects on natural biogeochemical cycles are already occurring (Gash et al. 1996). The atmosphere plays a key role in this process. The tropics are the part of the globe with the most rapidly growing population, the most dramatic industrial expansion and the most rapid and pervasive change in land use and land cover. Also the tropics contain the largest standing stocks of terrestrial vegetation and have the highest rates of photosynthesis and respiration. It is likely that changes in tropical land use will have a profound impact on the global atmosphere (Andreae 1998, Andreae and Crutzen 1997). A significant fraction of nutrients are transported or dislocated through the atmosphere in the form of trace gases, aerosol particles, and rainwater (Keller et al. 1991). Also the global effects of carbon dioxide, methane, nitrous oxide, and other trace gases have in the forest ecosystems a key partner. The large emissions of isoprene, terpenes, and many other volatile organic compounds could impact carbon cycling and the production of secondary aerosol particles over the Amazon region. Vegetation is a natural source of many types of aerosol particles that play an important role in the radiation budget over large areas (Artaxo et al. 1998). There are 5 major reservoirs in the Earth system: atmosphere, biosphere (vegetation, animals), soils, hydrosphere (oceans, lakes, rivers, groundwater), and the lithosphere (Earth crust). Elemental cycles of carbon, oxygen, nitrogen, sulfur, phosphorus, and other elements interact with the different reservoirs of the Earth system. The carbon cycle has important aspects in tropical forests due to the large amount of carbon stored in the tropical forests and the high rate of tropical deforestation (Jacob 1999). In Amazonia there are two very different atmospheric conditions: the wet season (mostly from November to June) and the dry season (July-October) (see Marengo and Nobre, this volume). Biomass burning emissions dominate completely the atmospheric concentrations over large areas of the Amazon basin during the dry season (Artaxo et al. 1988).

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Air Chemistry

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-40.10.493 ◽

1959 ◽

Vol 40 (10) ◽

pp. 493-498 ◽

Cited By ~ 2

Author(s):

Christian E. Junge

Keyword(s):

Atmospheric Chemistry ◽

Aerosol Particles ◽

Trace Gases ◽

Special Importance ◽

Physical Processes ◽

Industrial Activities ◽

Cent Increase ◽

Air Chemistry

The field of atmospheric chemistry, which is defined as the chemistry of trace substances in the troposphere, is reviewed. Trace substances can be present as aerosols or as gases. Major sources of aerosols are the ocean and industrial activities. The chemical composition of the aerosol particles is not only determined by their source but also by various processes in the atmosphere—notably, reactions with gas traces. Only little is known about trace gases like SO2, H2S, NH3 or NO2. Of special importance for meteorology is CO2 and its long-term fluctuations. The facts and possible reasons for its 10 per cent increase during this century are discussed. The last part of the discussion is concerned with the physical processes by which the trace substances are removed from the atmosphere, primarily the role of precipitation.

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High Precision Long-Term Monitoring of Radiatively Active and Related Trace Gases at Surface Sites and from Aircraft in the Southern Hemisphere Atmosphere

Journal of the Atmospheric Sciences ◽

10.1175/1520-0469(1999)056<0279:hpltmo>2.0.co;2 ◽

1999 ◽

Vol 56 (2) ◽

pp. 279-285 ◽

Cited By ~ 23

Author(s):

R. J. Francey ◽

L. P. Steele ◽

R. L. Langenfelds ◽

B. C. Pak

Keyword(s):

Southern Hemisphere ◽

High Precision ◽

Trace Gases ◽

Surface Sites ◽

Long Term Monitoring ◽

Term Monitoring

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Large enhancements in southern hemisphere satellite-observed trace gases due to the 2019/2020 Australian wildfires

10.1002/essoar.10507019.1 ◽

2021 ◽

Author(s):

Richard Pope ◽

Brian J Kerridge ◽

Richard Siddans ◽

Barry G Latter ◽

Martyn P Chipperfield ◽

...

Keyword(s):

Southern Hemisphere ◽

Trace Gases

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Emissions of atmospheric trace gases from vegetation burning

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1995.0035 ◽

1995 ◽

Vol 351 (1696) ◽

pp. 297-312 ◽

Cited By ~ 6

Keyword(s):

Trace Gases ◽

Biogeochemical Cycles ◽

Atmospheric Trace Gases ◽

Laboratory Conditions ◽

Vegetation Fires ◽

Wild Vegetation ◽

Field And Laboratory Conditions ◽

Trace Components ◽

Vegetation Burning

Emissions from vegetation fires are recognized as important contributions to biogeochemical cycles of elements. A brief overview is given on emissions of the trace components CO, CH 4 , and NO x determined under various field and laboratory conditions. The influence of these emissions of trace gases on their global turnover is shown to be important. Finally, the emissions due to burning of fuelwood for traditional cooking is compared to the influences of emissions due to wild vegetation fires.

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