Publications by authors named "Farnoush Ataei"
Article Synopsis
- The study investigates how high relative humidity (RH) influences the partitioning of biogenic oxidized organic molecules into secondary organic aerosols (SOA) using real-time measurements in a controlled lab setting.
- Results show significant increases in SOA mass (45%-85%) as RH rises from low to high levels, with semi-volatile compounds playing a key role in this process.
- The research explains that higher RH alters the chemical composition of aerosols, shifting toward more volatile species, and emphasizes the critical role of water content in promoting organic aerosol growth.
Article Synopsis
- Dimethyl sulfide (DMS) contributes to climate change by affecting cloud formation through its oxidation products, primarily methanesulfonic acid (MSA) and sulfuric acid (HSO), but predicting their levels accurately is difficult.
- Experiments conducted at CERN's CLOUD chamber showed that lowering the temperature significantly boosts the production of MSA from DMS oxidation, while HSO production remains relatively stable, resulting in a lower HSO/MSA ratio at cold temperatures.
- The research introduces a new DMS oxidation mechanism that increases MSA production estimates, significantly higher than previous models, revealing MSA's crucial role in the sulfur cycle and its impact on cloud condensation nuclei.
New particle formation in the upper free troposphere is a major global source of cloud condensation nuclei (CCN). However, the precursor vapours that drive the process are not well understood. With experiments performed under upper tropospheric conditions in the CERN CLOUD chamber, we show that nitric acid, sulfuric acid and ammonia form particles synergistically, at rates that are orders of magnitude faster than those from any two of the three components.
View Article and Find Full Text PDFArticle Synopsis
- - Iodic acid (HIO) can rapidly form aerosol particles in coastal areas, with nucleation rates surpassing those of sulfuric acid-ammonia under similar conditions.
- - Ion-induced nucleation involves the initial formation of IO followed by the addition of HIO, occurring efficiently at temperatures below +10°C, while neutral nucleation relies on a different process involving iodous acid.
- - Freshly formed HIO particles significantly contribute to fast particle growth and can effectively compete with sulfuric acid particle formation in unpolluted atmospheric regions.