Archive ScienceWatch



Markku Kulmala talks with and answers a few questions about this month's Fast Moving Front in the field of Environment & Ecology.
Kulmala Article: Formation and growth rates of ultrafine atmospheric particles: a review of observations
Authors: Kulmala, M;Vehkamaki, H;Petajda, T;Dal Maso, M;Lauri, A;Kerminen, VM;Birmili, W;McMurry, PH
Journal: J AEROSOL SCI, 35 (2): 143-176 FEB 2004
Addresses: Univ Helsinki, Dept Phys Sci, Div Atmospher Sci, POB 64,Gustaf Hallstrominkatu 2, FIN-00014 Helsinki, Finland.
Univ Helsinki, Dept Phys Sci, Div Atmospher Sci, FIN-00014 Helsinki, Finland.
Finnish Meteorol Inst, FIN-00880 Helsinki, Finland.
(addresses have been truncated)

 Why do you think your paper is highly cited?

I believe that this paper is highly cited because it provides a first comprehensive summary of observed atmospheric new particle formation—the name given to the spontaneous formation of new nanometer-sized particles in the atmosphere. It also gives explanations how to obtain particle formation rates and growth rates from observations.

  Does it describe a new discovery, methodology, or synthesis of knowledge?

It describes a synthesis of existing knowledge on new particle formation in the atmosphere. The main discovery is that new particle formation is now a global phenomenon.

  Would you summarize the significance of your paper in layman’s terms?

The paper describes how and in which conditions/environments new nanoparticles are formed in the atmosphere. The main result is that atmospheric nucleation is observed at various environmental conditions practically all around the world. In other words, it is a global phenomenon.

  How did you become involved in this research and were any particular problems encountered along the way?

I began investigating atmospheric new particle formation in 1991. Before that, I had studied nucleation (gas to liquid) theory.

In that time—the early 1990s—it was believed that atmospheric nucleation was a rare phenomenon. In 1996, I started continuous measurements to evaluate the dynamics of atmospheric aerosol particles. The main result found so far is the formation of new aerosolparticles at nm size and their subsequent growth to ca 80-100 nm in size.

During these studies we have also shown that new particle formation occurs frequently. In our paper we were able to show that new particle formation occurs all over the world. This conclusion is a new result.

  Where do you see your research leading in the future?

Our main objective is to contribute to the reduction of scientific uncertainties concerning global climate change issues, particularly those related to aerosols and clouds. We aim at creating a deeper understanding of the dynamics of aerosol particles and ion and neutral clusters in the lower atmosphere, with the emphasis on biogenic formation mechanisms and their linkage to biosphere-atmosphere interaction processes, biogeochemical cycles, and trace gases. The relevance and usage of these results within the context of global-scale modelling, and the development and utilization of the newest measurement techniques are addressed.

  Do you foresee any social or political implications for your research?

As outlined above, the foreseen result as it pertains to the understanding of global radiative balance and climate change is a crucial element in the evolving political worldview of the environment.

Professor Markku Kulmala
Department of Physics
University of Helsinki
Helsinki, Finland

2008 : March 2008 - Fast Moving Fronts : Markku Kulmala