Ecole Doctorale des Sciences Fondamentales
Title of the thesis:
Estimation and nowcasting of rain over an urban basin
Supervisor :
Dr. Joël Van Baelen
Laboratory :
Laboratoire de Météorologie Physique (LaMP)
University :
Université Blaise Pascal Clermont Ferrand
Email and Phone :
j.vanbaelen@opgc.univ-bpclermont.fr
/
+33 – 4 – 73 40 54 26
Summary :
With the effect of climate change, our society is facing ever more recurrent episodes of extreme and
localized precipitation events which can cause extensive damages to private and public properties but
also loss of lives in case of flash floods and inundations. Hence, it becomes necessary for urban
entities potentially at risk to be able to rely on precise nowcasting of the rain evolution over its
jurisdiction and its surrounding catchment basins.
LaMP operates two small X band high space and time resolution precipitation radars and, in
collaboration with Clermont Community, it has access to a dense network of real time rain gages over
the Clermont Ferrand urban basin. Furthermore, LaMP has a long standing expertise in numerical
simulations of precipitating systems.
Hence, building on the experience acquired in the laboratory over the last six years over numerous
campaigns (Clermont Ferrand, COPS, HYMEX), the research work of this thesis project will focus on
three main axis:

Optimal estimates of precipitations with X band radars, in particular accounting for attenuation
by considering estimates based on combining multiple radar observations or making use of
dual polarization systems, as well as for the different specific rain regimes observed;

Merging of long range C and S band meteorological radar data with the local X band radar
data for large scale depiction of the system, together with the merging of measurements from
the local rain gage network combined with the high space and time resolution from the local X
band radars to characterize the small scale features, in order to provide a precise rain
estimate through adapted conditional merging, kriging or autocalibration methods;

Nowcasting of rain through a combination of approaches based on radar data extrapolation
techniques as well as high resolution short time scale numerical weather prediction.
Ecole Doctorale Sciences Fondamentales – 24, avenue des Landais – BP 80026 - 63171 AUBIERE CEDEX
CHIMIE – MATHEMATIQUES – PHYSIQUE – SCIENCES DE L’UNIVERS
site web : http://edsf.univ-bpclermont.fr
Directeur : Pr Patrice Malfreyt
tél. 04.73.40.72.04
E-mail : Patrice.Malfreyt@univ-bpclermont.fr
Secrétariat : Sylvie Desmet Rigaud
tél. 04.73.40.53.76
E-mail : Sylvie.Desmet@univ-bpclermont.fr
Ecole Doctorale des Sciences Fondamentales
Therefore, the overarching goal of this thesis project is to provide a tool to follow in details the
evolution of rain over an urban basin by the best combined use of local data, and to provide short term
forecasts capable to feed adequately urban hydrological models and, eventually, propose a help for
decision making in case of crisis.
The ideal candidate will have a demonstrated background in analysis and signal processing methods,
remote sensing physics, as well as atmospheric dynamics principles. Further knowledge in radar
measurement principles as well as good programming skills are also desired. Although autonomous to
carry on his/her research, he/she will also be part of a small team to apprehend the different aspects
of the thesis work, hence good relational and communication skills are essentials.
Ecole Doctorale Sciences Fondamentales – 24, avenue des Landais – BP 80026 - 63171 AUBIERE CEDEX
CHIMIE – MATHEMATIQUES – PHYSIQUE – SCIENCES DE L’UNIVERS
site web : http://edsf.univ-bpclermont.fr
Directeur : Pr Patrice Malfreyt
tél. 04.73.40.72.04
E-mail : Patrice.Malfreyt@univ-bpclermont.fr
Secrétariat : Sylvie Desmet Rigaud
tél. 04.73.40.53.76
E-mail : Sylvie.Desmet@univ-bpclermont.fr