1-6-anhydro-beta-glucopyranose and retene

Cryoconite is a dark, dusty aggregate of mineral particles, organic matter, and microorganisms transported by wind and deposited on glacier surfaces. It can accelerate glacier melting and alter glacier mass balances by reducing the surface albedo of glaciers. Biomass burning in the Tibetan Plateau, especially in the glacier cryoconites, is poorly understood. Retene, levoglucosan, mannosan and galactosan can be generated by the local fires or transported from the biomass burning regions over long distances. In the present study, we analyzed these four molecular markers in cryoconites of seven glaciers from the northern to southern Tibetan Plateau. The highest levels of levoglucosan and retene were found in cryoconites of the Yulong Snow Mountain and Tienshan glaciers with 171.4 ± 159.4 ng g

Topics: Biomarkers; Biomass; Dust; Environmental Monitoring; Fires; Galactose; Glucose; Ice Cover; Mannose; Phenanthrenes; Tibet; Wind

This study was conducted at three sites of different characteristics in São Paulo State: São Paulo (SPA), Piracicaba (PRB) and Mata Atlântica Forest (MAT). PM(10), n-alkanes, pristane and phytane, PAHs, water-soluble ions and biomass burning tracers like levoglucosan and retene, were determined in quartz fiber filters. Samplings occurred on May 8th to August 8th, 2007 at the MAT site; on August 15th to 29th in 2007 and November 10th to 29th in 2008 at the PRB site and, March 13th to April 4th in 2007 and August 7th to 29th in 2008 at the SPA site. Aliphatic compounds emitted biogenically were less abundant at the urban sites than at the forest site, and its distribution showed the influence of tropical vascular plants. Air mass transport from biomass burning regions is likely to impact the sites with specific molecular markers. The concentrations of all species were variable and dependent of seasonal changes. In the most dry and polluted seasons, n-alkane and cation total concentrations were similar between the megacity and the biomass burning site. PAHs and inorganic ion abundances were higher at São Paulo than Piracicaba, yet, the site influenced by biomass burning seems to be the most impacted by the organic anion abundance in the atmosphere. Pristane and phytane confirm the contamination by petroleum residues at urban sites; at the MAT site, biological activity and long range transport of pollutants might influence the levels of pristane.

Topics: Aerosols; Air Pollutants; Atmosphere; Biomass; Brazil; Cities; Diterpenes; Environmental Monitoring; Glucose; Incineration; Particulate Matter; Phenanthrenes; Polycyclic Aromatic Hydrocarbons; Terpenes; Trees

The Yosemite Aerosol Characterization Study (YACS) was conducted in the summer of 2002 to investigate sources of regional haze in Yosemite National Park. Organic carbon and molecular source marker species size distributions were investigated during hazy and clear periods. More than 75% of the organic carbon mass was associated with submicron aerosol particles. Most molecular marker species for wood smoke, an important source of particulate matter during the study, were contained in submicron particles, although on some fire influenced days, levoglucosan shifted toward larger sizes. Various wood smoke marker species exhibited slightly different size distributions in the samples, suggesting different, size dependent emission or atmospheric processing rates of these species. Secondary biogenic compounds including pinic and pinonic acids were associated with smaller particles. Pinonaldehyde, however, exhibited a broader distribution, likely due to its higher volatility. Dicarboxylic acids were associated mainly with submicron particles. Hopanes, molecular markers for vehicle emissions, were mostly contained in smaller particles but exhibited some tailing into larger size classes.

Topics: Acids; Aerosols; Air Pollutants; Air Pollution; Biomarkers; California; Carbon; Dicarboxylic Acids; Glucose; Organic Chemicals; Particle Size; Particulate Matter; Phenanthrenes; Phenols; Smoke; Statistical Distributions; Terpenes