Synergystic Use of Satellite Data, Ground-based Observations,
Back-trajectory Analysis and a Global CTM Results for Studies of Tropospheric Trace Gases and Aerosols over the Mediterranean

A contribution to ACCENT-TROPOSAT-2, Task Group 2

Maria Kanakidou

Environmental Chemical Processes Laboratory (ECPL), Dept. of Chemistry, University of Crete,
P.O.Box 1470, 71409 Heraklion, Greece
Tel.:  +30-2810 393 633/667,
Fax:  +30-2810 393 601
web site:;

The project is a feasibility study of the synergistic use of satellite data, ground based observations over the Mediterranean, back trajectory analysis, box and global 3-D chemistry transport model results to evaluate the impact of distinct pollution sources (like urban pollution, biomass burning fires, etc) on oxidant and aerosol levels in the Mediterranean, the consequences on regional climate and the seasonal and inter-annual variations (since 1997).

Priority is given to the use of the European satellite products (like GOME (Global Ozone Monitoring Experiment) and SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric CHartographY)). The ground based observations consist of the gas phase, aerosol data and auxiliary measurements at Finokalia monitoring station of ECPL as well as data regarding Mediterranean area and collected during EU funded projects (ADIOS, MOZAIC (aircraft data), etc).

Box models that have been developed by ECPL to study Boundary Layer chemistry will be applied to selected case studies to evaluate the potential of chemical built up of oxidants in the observed air masses. The global CTMs TM3/TM5 will be used to evaluate budgets of trace constituents with focus on East Mediterranean region after being evaluated against the observations.

Finally the satellite observations of aerosols and oxidants will be combined by the use of the CTM to evaluate the impact of aerosol on the oxidant levels in the area and its variability over the past 10 years by modifying the photodissociation rates of the oxidants and acting as surface for heterogeneous reactions. Selected case studies will be analysed on the basis of ground based aerosol chemical composition and oxidant observations and auxiliary data.

The short-term (18-month) objective within AT2 focuses on

   identifying the major reasons of variations of tropospheric O3 in the East Mediterranean during spring (in 1999), and

   investigating the impact of European pollution on NO2 and HCHO tropospheric columns in the area.

For the next year we plan to continue our study on O3, HCHO and NO2 analysis for the summer 2000 that was an intensive summer in terms of forest fires over Greece to define the fingerprint of these fires and their environmental impact. For this, we will examine satellite observations of NO2, HCHO and CO in relationship to model predictions and in-situ observations.


On the longer term (5-year perspective), we will continue to exploit the combined benefits of satellite data and global chemistry-transport model capabilities as outlined above to understand and document the impact of distinct pollution sources on oxidant and aerosol levels in the Mediterranean, evaluate the potential impact of aerosols on oxidant levels and the consequences on regional climate, as well as the seasonal and inter-annual variations of these effects.

For most of these projects, we will be making increasing use of the satellite based GOME and SCIAMACHY data to analyse the tropospheric amount of the trace gases O3 and its precursors NO2 and HCHO as well as CO from MOPITT measurements and aerosols from MERIS.

Approximate manpower and cost








Personnel / man-years







Yearly cost (k)







Likely funding agencies

Greek Ministry of Education, Greek Ministry of Development (General Secretariat of Research and Technology), European Union


Dr. Nikolaos Mihalopoulos, Dr. Giorgos Kouvarakis and Maria Sfakianaki,                     


Address: Environmental Chemical Processes Laboratory (ECPL), Dept. of Chemistry, University of Crete, P.O.Box 1470, 71409 Heraklion, Greece


 Return to the top of the page