Search

Measurements of number size distributions of submicron aerosols have been performed at the Eastern part of Mediterranean as part of an extensive measurement campaign to study photo-oxidants and aerosols (SUB-AERO Project). The measurements were made at the Finokalia station on the island of Crete (Greece) and onboard the research vessel 'Aegaeon'. Two campaigns were performed during July 2000 and January 2001 using two scanning mobility particle sizers. The particle distributions measured in the range between 7.8 < d < 327 nm during the summer measurements and between 7.5 < d < 316 nm during the winter measurements, where d is the mobility particle diameter. The concentration of ultrafine particles (7.5 < d < 30 nm) was higher during the winter period and varied mainly between 5 × 10 and 2 × 10 cm with concentration peak values for this mode exceeding 1 × 10 cm. During the summer campaign, an average number concentration of 1 × 10 cm at Finokalia and about 5 × 10 cm aboard the 'Aegaeon' vessel was measured. An average concentration of 1 × 10 cm was measured for the particles in the size range between 30 and 100 nm, whereas in the size range 100-300 nm, the measured concentration ranged between 1 × 10 and 5 × 10 cm. Diurnal patterns in number concentrations were observed in connection with the transport of air masses and local sources. During the winter period, three nucleation events were observed in connection with the appearance of a particle mode at 20 nm. [ABSTRACT FROM AUTHOR]