Supervisors info:
Τόμπρου Μαρία Αναπλ. Καθηγήτρια ΕΚΠΑ (Επιβλέπουσα), Παπαγιάννης Αλέξανδρος Καθηγητής ΕΜΠ, Γιαννακάκη Ελένη Λέκτορας ΕΚΠΑ
Summary:
The aim of this master thesis is to compare experimental data from the combined
information derived from the terrestrial lidar measurements of National
technical University of Athens and the sun photometer CIMEL, member of the
AERONET network of NASA, with simulations by WRF-Chem model (National and
Kapodistrian University of Athens) in order to get conclusions on the
consistency between them as well as to investigate the possibility of combining
the information they provide.
The geographical area of the application is Athens and the selected time period
coincides with the conduction of the experimental campaign HYGRA-CD, during
May-June 2014. Six different cases were examined in total. For the demands of
this thesis the algorithm LIRIC (LIdar Radiometer Inversion Code) was used and
programs in Matlab were also developed for data processing.
Chapter 1 is an introduction and deals with airborne particles in the
atmosphere (sources, chemical composition, properties). In chapter 2 there is
an extensive description of the instruments used from which data were drawn,
the algorithm, the model and the entire analysis of the measurements and
retrieved results. In Chapter 3, the experimental results are analyzed for
selected dates of interest in terms of the presence of aerosols. This thesis is
completed in the fourth chapter, presenting our conclusions, discussions and
future prospects.
For the case studies 22/05, 05/06, 11/06 and 12/06, of year 2014 there is
long-range transport of polluted air masses due to the prevailing northern wind
over the area of Greece. There is a good correlation between the model and the
TSI concentrations, near the surface. However, WRF_chem simulates lower mass
concentrations at higher altitudes and up to 5 km due to the lack of biomass
burning emissions that are important during the examine period in the region.
On 17/05 and 30/05 the wind flow is mostly from the west and so larger values
of mass concentration are simulated with a good correlation between calculated
and simulated values for the case of 30/05.
Keywords:
Aerosols, LIRIC, Lidar, WRF-Chem, Size distribution
