Accession Number : AD0724046

Title :   Condensation Nuclei Measurements in an Urban Area,

Corporate Author : ISTITUTO DI FISICA DELL'ATMOSFERA ROME (ITALY)

Personal Author(s) : Colacino,M. ; Franco,R. ; Vivona,F. M.

Report Date : 09 MAR 1970

Pagination or Media Count : 7

Abstract : Systematic countings of condensation nuclei were carried out at IFA--Chemical Laboratory (Rome, Italy) with a Nolan-Pollak nuclei counter. The data were elaborated every month and show that: (1) dry weather with an overcast sky is generally associated with a large number of nuclei; on the contrary, clear sky is almost always associated with a smaller number of nuclei. This behaviour is explained by the fact that overcast sky corresponds to a subsidence situation, while clear sky is associated with strong winds, which cause air turbulence and, as consequences, air mixing and a decrease in the condensation nuclei number; (2) during rain the condensation nuclei number is low due to the wash-out effect of the precipitation; (3) a remarkable correlation between air relative humidity and condensation nuclei number was found. (Author)

Descriptors :   (*ATMOSPHERES, AEROSOLS), (*AIR POLLUTION, URBAN AREAS), CONDENSATION, NUCLEATION, COUNTING METHODS, HUMIDITY, EXHAUST GASES, HEATING, PARTICLES, ITALY

Subject Categories : Atmospheric Physics
      Air Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE