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Updated: Jun 21, 2026
09:01
An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles
Published on: April 19, 2018
Surface-level fine particle mass concentrations: from hemispheric distributions to megacity sources
1Envair/Aerochem, Placitas, NM 87043, USA. dhidy113@comcast.net
Journal of the Air & Waste Management Association (1995)
|August 4, 2009
Summary
Fine particle chemical climate knowledge has improved since 1990. Global distributions show highest concentrations near industrial areas, dominated by sulfate and organic carbon.
Area of Science:
- Atmospheric chemistry and physics
- Environmental science
- Geochemistry
Background:
- Significant advancements in understanding the chemical climate of fine particles have occurred since 1990.
- Junge's 1960s compilation provided foundational data for fine particle research.
Purpose of the Study:
- To estimate the worldwide baseline distribution of fine particle concentrations.
- To deduce the geographical distribution of fine particle characteristics.
- To analyze the composition and sources of fine particles on synoptic and continental scales.
Main Methods:
- Synthesis of disparate ground-level measurement data from all continents.
- Analysis of fine particle mass concentrations and chemical composition.
- Geographical mapping of particle characteristics and source attribution.
Main Results:
- Worldwide fine particle concentrations vary, with highest regional mass concentrations (1-80 microg/m3) near high population and industrial density areas.
- Fine particles are dominated by non-sea salt sulfate and organic carbon (approx. 25% each by mass).
- Long-range transport of pollution creates persistent regional gradients, especially in the Northern Hemisphere; data is sparse in the Southern Hemisphere.
Conclusions:
- Fine particle distribution and composition are strongly influenced by anthropogenic sources in populated and industrialized regions.
- Natural sources like dust, sea salt, and wildfires contribute significantly to intermittent particle loadings.
- Understanding fine particle chemical climate is crucial for air quality assessment and climate modeling.
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