Airborne measurement of ionic components in aerosol particles during AAMP98

Abstract

During the Arctic Airborne Measurement Program 1998 (AAMP 98), atmospheric aerosols were collected onto PTFE filters from the inlet of Gulfstream II through a diffuser installed in the cabin. During the sampling the number concentrations of aerosol particles with diameters larger than 0.3 µm were continuously monitored with an optical particle counter (OPC) connected to the diffuser in parallel to the filter sampling line. The data from the OPC were transferred by serial communication to a computer and recorded. The filter samples were brought back to the laboratory, then extracted with ion exchanged water and the concentrations of anions and cations were analyzed by ion chromato­graphy. Detected ions were as follows: Cl^-, N02^-, 1 , N03^-, SO4^2-, Na^+, NH4+, K^+, Mg^2+, Ca^2+. Even at high altitudes Cl^- and Ca^2+ were frequently detected, in addition to SO4^2- , which is known as a major ionic component in the stratosphere.