The principal goal of ESCOBA (European Study of Carbon in the Ocean, Biosphere and the Atmosphere) is to investigate, quantify, model and eventually predict the behaviour of the global carbon cycle in response to perturbations by man and with respect to its interaction with the physical climate system on timescales of up to several hundred years.
The present project represents ESCOBA-Atmosphere which has two specific objectives:
(1) To monitor and assess the information contained in atmospheric measurements of C02 and other tracers linked to the global carbon cycle, and (2) to synthesize the combined knowledge on the carbon cycle into comprehensive global prognostic models, to validate these models and to perform scenario calculations.
These objectives pertain to theme 1, area 1 1.1, "Basic processes in the climate system" research task 5 on global cycles of greenhouse gases. In order to achieve these objectives ESCOBA-Atmosphere will conduct the following tasks:
(1) A monitoring program of the atmospheric concentration of C02 and its stable (13C/12C and 180/160 in C02) and radioactive (14C/C) isotope ratios. This monitoring program is focussed on the North Atlantic, the European continent and on the Tropical Indian Ocean, which represent critical gaps in the currently operating global monitoring networks. These measurements are supplemente by observations of SF6, in order to provide a diagnostic tool to validate the atmospheric transport models used in the project. In the course of the project a new capability of measuring oxygen/nitrogen ratios in atmospheric air will be developed.
(2) A series of model simulation studies: (a) inversion studies with atmospheri transport models in order to establish constraints on magnitude and location of surface sources and sinks of atmospheric C02 from atmospheric observations, (b) validation simulations of surface fluxes generated by prognostic, highresolution models of the terrestrial and oceanic carbon reservoirs and (c) a series of scenario calculations of the future atmospheric C02 concentration based on scenarios of future energy and landuse using high-resolution, coupled comprehensive models of the global carbon cycle as developed and validated within ESCOBA.
KEYWORDS(maxlO): greenhouse gases, carbon dioxide, carbon cycle