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Formation and growth rates of ultrafine atmospheric particles: a review of observations
Evolution of Organic Aerosols in the Atmosphere
A unifying model framework describing the atmospheric evolution of OA that is constrained by high–time-resolution measurements of its composition, volatility, and oxidation state is presented, which can serve as a basis for improving parameterizations in regional and global models.
Flood or Drought: How Do Aerosols Affect Precipitation?
A conceptual model is proposed that explains this apparent dichotomy of pristine tropical clouds with low CCN concentrations rain out too quickly to mature into long-lived clouds and heavily polluted clouds evaporate much of their water before precipitation can occur.
Formation and growth of fresh atmospheric aerosols: eight years of aerosol size distribution data from SMEAR II, Hyytiälä, Finland
We analyzed size distributions measured continuously at a boreal forest measurement site at Hyytiala, Finland between 1996 and 2003. From the eight-year data we identified days when new aerosol…
An improved parameterization for sulfuric acid-water nucleation rates for tropospheric and stratospheric conditions
 In this paper we present parameterized equations for calculation of sulfuric acid–water critical nucleus compositions, critical cluster radii and homogeneous nucleation rates for tropospheric and…
A large source of low-volatility secondary organic aerosol
It is found that a direct pathway leads from several biogenic VOCs, such as monoterpenes, to the formation of large amounts of extremely low-volatility vapours, helping to explain the discrepancy between the observed atmospheric burden of secondary organic aerosol and that reported by many model studies.
Station for Measuring Ecosystem-Atmosphere Relations: SMEAR
We planned and implemented the SMEAR II and I measuring systems to measure material and energy fluxes between forest ecosystem and its surroundings and within the ecosystem. In addition, we measured…
Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation
First results from the CLOUD experiment at CERN are presented, finding that atmospherically relevant ammonia mixing ratios of 100 parts per trillion by volume, or less, increase the nucleation rate of sulphuric acid particles more than 100–1,000-fold and ion-induced binary nucleation of H2SO4–H2O can occur in the mid-troposphere but is negligible in the boundary layer.
Cluster activation theory as an explanation of the linear dependence between formation rate of 3nm particles and sulphuric acid concentration
According to atmospheric observations new particle formation seems to be a function of sulphuric acid concentration to the power from one to two. The nucleation theorem then predicts that the…
Temperature and light dependence of the VOC emissions of Scots pine
- V. Tarvainen, H. Hakola, H. Hellén, J. Bäck, P. Hari, M. Kulmala
- Environmental Science
- 19 October 2004
Abstract. The volatile organic compound (VOC) emission rates of Scots pine (Pinus sylvestris L.) were measured from trees growing in a natural forest environment at two locations in Finland. The…