The Weybourne Atmospheric Observatory

Abstract

The Weybourne Atmospheric Observatory (WAO) was set up in 1992 with funds provided by BP (Norway) plc and the Natural Environment Research Council (NERC) of the U.K. It was established as Station No. 11 in the TOR Network of EUROTRAC (TOR= Tropospheric Ozone Research) with the original intention of making long-term studies of surface ozone and its precursors in Western Europe. Its main use so far, however, has been as a well-located site for detailed studies of atmospheric chemical processing in extensive campaigns. The papers presented in this special section of JAC reflect this situation. The observatory is located on the north Norfolk coast in a converted World War II Gunnery Blockhouse divided into three main internal spaces: an optical laboratory used principally for differential optical absorption spectroscopy (DOAS) measurements; an instrument room housing a large range of continously running instruments for measuring many trace gases involved with ozone production; and an office/mess room which acts as a data storage and display centre, along with providing a few creature comforts. The overall dimensions of the observatory are 16 m (L), 4 m (W) and 3 m (H). The building is located less than 100 m from the pebble beach shoreline, at an altitude of 20 asl. A ten-metre scaffolding tower is strapped to the seaward side of the observatory, providing a platform for air sampling as well as radiometric and meteorological measurements. A photograph of the observatory is shown in Figure 1. The ground plan of the observatory in Figure 2 illustrates the extensive range of instruments that have been used routinely for detailed studies of air chemistry. These include instruments for measuring hydrocarbons, carbon monoxide, NOx , NOy, ozone, speciated peroxides, formaldehyde, PAN, peroxy radicals (HO2 + RO2), condensation nucleus (CN) counts, and the photolysis rate coefficients of both ozone and NO2 (j(O1D) and j(NO2)). The latter two instruments are located on