Introduction

Abstract

A comprehensive programme has been set up in Europe to use modelling and data assimilation to monitor the composition of the Earth’s atmosphere and predict air quality. The core development and initial operation are being undertaken in a project called MACC (Monitoring Atmospheric Composition and Climate) operated by a 45-partner consortium coordinated by the European Centre for Medium-Range Weather Forecasts (ECMWF). MACC is part of Europe's GMES (Global Monitoring for Environment and Security) initiative.

MACC has four main components. The input data component acquires satellite and in situ observations and carries out preparatory processing of them. It also collates and refines estimates of surface emissions of key species, with a particular emphasis on the highly variable emissions from fires. Primary global and regional components operate the data assimilation and modelling systems that provide basic monitoring and forecasting products, Derived information on climate forcing, air quality, stratospheric ozone, UV radiation and resources for solar power generation is also provided. The fourth component operates the interface to downstream service providers and other users, and supports the development of policy on atmospheric pollution.

The global MACC system is based on the ECMWF numerical weather prediction system. Capabilities have been added for modelling and assimilating data on aerosols and several greenhouse and fast-reacting gases. The system is being employed to produce near-real-time and retrospective coupled analyses of atmospheric trace constituents and the associated meteorological fields; ancillary systems infer corrections to the surface fluxes of carbon dioxide and methane. MACC also provides higher resolution analyses and forecasts for Europe: the global forecasts provide boundary conditions to an ensemble of nationally-developed regional air-quality forecasting systems run cooperatively over a common domain.

An overview of the project will be presented and examples of how the system performs will be discussed. Recent cases of dust storms, plumes from volcanic eruptions and fires will be included.