Problems to be solved

Theoretical predictions of future levels of the most important greenhouse gases cannot be verified without knowledge of today's sources (and sinks) of these gases. Furthermore, without a sound and credible scientific understanding, it is very difficult to gain consensus to move forward on policy. Continued uncertainty about for example the importance of carbon sinks or the exact national greenhouse gas emissions will further limit the implementation and use of instruments aimed at reducing these emissions.
In recent years it has become clear that the traditional atmospheric greenhouse gas observing system has severe gaps. Knowledge of for example the global carbon budget derived from atmospheric data was based on sparse sampling at "remote" stations located far from the continents. This marine network is good enough to infer CO₂ fluxes at the hemispheric scale, but cannot resolve these fluxes on the longitudinal scale. An example of the controversy to which this can lead is the current debate on the apportionment of the Northern Hemispheric CO₂ sink between Northern America and Eurasia.

Scientific objectives and approach

The CHIOTTO-Infra project objective is to build an improved infrastructure for the continuous monitoring of the concentrations of greenhouse gases on the European continent above the surface layer using tall towers. The project is based on and extends existing research projects (AEROCARB, T-COS and TACOS). This will be an important step towards a fully operational continuous observing system in the framework of the Kyoto Protocol for the sources and sinks of the most important greenhouse gases (CO₂, CH₄, N₂O, CO, SF₆) over Europe.
An important aspect of the objective is the establishment of high quality calibrations for the existing and new atmospheric measurement stations, and the implementation of a near-online data-transmission system for tall tower measurements.
We will monitor the intercomparability of the concentration measurements between the institutes operating the air sampling networks. Quality controlled atmospheric concentration, CO₂ flux and additional meteorological data will be archived in a data center accessible to the scientific community through the World Wide Web.
We will integrate existing flux towers in the vicinity of the tall towers with the atmospheric stations networks in a synergetic approach enabling the tall towers to become atmospheric monitoring sites for use in transport models.

Expected impacts

We have identified as major end users of the CHIOTTO-Infra data a large scientific community worldwide in the field of atmospheric sciences as well as stakeholders and policy makers involved in the Post-Kyoto decision process related to the sources and sinks of greenhouse gases. Once fully operational, this observing system for sources and sinks of greenhouse gases will be the only independent tool for evaluating the policy agreements, such as the Kyoto protocol.
Used in a new suite of global, continental and regional models developed in for example projects like AEROCARB and RECAB, the observational dataset acquired in this project will serve as the basis of inverse calculations of the fluxes of the most important greenhouse gases and trends of these fluxes in the measurement period.