Introduction

The GOME NRT 1999/2000 Campaign (December 1999-May 2000) is set up as a support for the three major measurement campaigns SOLVE/EUROSOLVE, THESEO 2000 (Third European Stratospheric Ozone Experiment), and TOPSE (Tropospheric Ozone Production about the Spring Equinox). This is a joint collaboration between the Institutes of Environmental Physics (IUP) at the Universities of Bremen and Heidelberg, respectively, the German Remote Sensing Data Center part of the German Aerospace Center (DLR/DFD), the Space Research Organization (SRON, The Netherlands), the Norwegian Institute for Air Research (NILU, Norway), the Swedish Space Corporation (SSC, Sweden), the European Ozone Research Coordinating Unit (EORCU, UK), the European Space Agency ESA and the National Center for Atmospheric Research (NCAR, Boulder) and is supported in parts by the EU funding within the GODIVA and EUROSOLVE project.

In the framework of the Third European Stratospheric Experiment on Ozone (THESEO2000) the EU GODIVA and EIUROSOLVE projects provide near real time (NRT) data products from the Global Ozone Monitoring Experiment (GOME) to aid the coordination of field campaigns around Kiruna and in the Arctic. The NRT data products derived from the GOME spectral data encompass ozone total columns and profiles, total columns of NO2 and BrO, and slant columns of OClO. Since the GOME maps and trace gas data are produced in near real time, the results of the NRT data analysis is considered preliminary. The NRT level 1 data products (radiance and solar irradiance) are generated by the GOME data processor (GDP) located at ESA's Kiruna ground station, which is one of five ESA stations receiving global data from the ERS-2 (European Remote Sensing satellite) carrying GOME. The GDP was developed and is operated by DLR/DFD in Oberpfaffenhofen; the internet connection between Kiruna GS and NILU for the level-1 data transmission is provided by the Swedish Space Corporation.

THESEO is an European campaign to study the anthropogenic effects on the ozone depletion and study the links between tropics, middle latitudes, and the North polar region and between the lower stratosphere and the upper troposphere. THESEO is funded by the European Commission DG XII-D1 and coordinated by the European Ozone Research Coordinating Unit (EORCU).

The SAGE III Ozone Loss and Validation Experiment (SOLVE) is an American measurement campaign designed to examine the processes controlling ozone levels at mid- to high latitudes. Measurements will be made in the Arctic high-latitude region in winter using the NASA DC-8 and ER-2 aircraft as well as balloon platforms and ground-based instruments. The GOME NRT activities are supported in part by the EUROSOLVE project, which is the EU funded European contribution to the American SOLVE campaign in Kiruna.

The goal of the TOPSE experiment is to investigate the chemical and dynamic evolution of tropospheric chemical composition over continental North America during the winter/spring transition, with particular emphasis on the springtime ozone maximum in the middle troposphere. Measurements will be made on the NCAR C-130 aircraft during February to May, 2000, along transects from Denver, CO to north of Thule, Greenland. The aircraft payload includes in-situ measurements of radicals, reservoirs, and tracers species as well as remote-sensing measurements of aerosols and ozone. An enhanced ozone sonde program is also being implemented. TOPSE is sponsored by the United States National Science Foundation (NSF).

Making data products available to scientific and meteorological end users is one of the main objectives of the GOME Data and Interpretation and Validation Project (GODIVA). GODIVA is a collaboration between the Space Research Organization Netherlands (SRON), University of Bremen (UB), NILU, University of Leicester (UL), University of Heidelberg (UH), KNMI, and the Finish Meteorological Institute (FMI).

Regular NRT GOME images (mainly ozone) can be found at the websites of the University of Bremen, KNMI, and DLR/DFD.