To address the above objectives, POLARCAT will carry out four major (and a few smaller) co-ordinated measurement campaigns in the Arctic. These will involve about 12 different aircraft (some involved in more than one mission), a ship, and all the major Ar ctic surface stations, for which long-term studies will also be made. In addition, data from a large suite of satellite platforms will be analyzed and new satellite products developed (e.g., polar composites of available satellite data). A suite of models will be used to interpret the measurement data.
Of the four major measurement campaigns, one will be in winter (February 2008), two in spring (March/April 2007, April 2008), and one in summer (June-August 2008). The main objectives for the winter/spring campaigns are to revisit the Arctic Haze problem by performing air- and ship-borne measurements with modern instrumentation, both in the European and in the North American part of the Arctic, and to explore the transition from the dark winter to the photo chemically active spring. The summer campaign will explore the relevance of boreal forest fires as a pollution source for the Arctic, including radiative effects in the atmosphere and via changes in snow/ice albedo. During all campaigns Asian, European an d North American contributions to gaseous pollutants and aerosols (in particular Black Carbon, BC) shall be determined.