The mediterranean campaign of photochemical tracers—transport and chemical evolution (MEDCAPHOT-TRACE): an outline

Abstract

The MEDCAPHOT-TRACE experiment took place in the Greater Athens Area (GAA) during the summer of 1994 (20 August–20 September) with the participation of 16 European scientific groups. The purpose of MEDCAPHOT-TRACE was to study the chemical and meteorological evolution of ozone and related trace gases (over land and sea), modulated by the various synoptic and local meteorological conditions (sea/land breeze circulation, local winds, inversion layers, etc.) in one of the largest urban agglomerations in the Mediterranean region. In addition to the operating stations of the existing air pollution monitoring network, 18 new stations operated in the vicinity of the GAA. The scientific instrumentation used in the experiment consisted of ground-based air pollution measuring systems (gas analysers and gas chromatographs), integrated-path air pollution measuring systems (DOAS systems), ground-based laser remote sensing systems (LIDAR technique), meteorological instrumentation (slow- and fast-response) and aircraft measurements (air pollution and meteorological). Although the monitoring programme was intensified during the 10 d period of aircraft measurements, the larger proportion of measurements was carried out on a regular day-and-night basis throughout the 30 d period of the campaign. The data collected cover a variety of meteorological situations and will be made available for general use in the near future. An introduction to some of the results are given in the following.