The Conference on Meteorology, Climatology and Atmospheric Physics (COMECAP) has been co-organized by the
 Hellenic Meteorological Society on a biennial basis since 1992. After about 20 years, this years’ 
15th COMECAP returns to Ioannina and is co-organized by the Laboratory of Meteorology and Climatology
 of the University of Ioannina, the Hellenic Meteorological Society and the Mariolopoulos-Kanaginis 
Foundation for Environmental Sciences. The unusual circumstances brought by the Covid-19 pandemic have
 led to its delay by a year, but also carved a new hybrid format for the first time in its 30-year history
. In meteorological terms, “every cloud has a silver lining”, which means that we had to innovate to 
partially compensate for the loss of some of the in-person interactions and the carefree mask-less times.
 With the invaluable help and know-how of Conferre, around 100 online and 125 onsite participants will 
interact through a novel online platform available on any device and share their research results and 
breakthrough ideas, either through onsite and online talks or through e-posters that are projected on 
onsite screens substituting for the poster boards, or on any device. Around 40% of these participants are 
graduate students presenting the results of their MSc or Phd theses, illustrating that COMECAP continues
 to instigate the interest about Atmospheric Sciences to young researchers. In this years’ conference, a 
total of 285 abstracts were submitted and resulted in 214 submitted full papers that underwent a thorough 
review process and will be presented at the conference. The papers cover a wide range of topics on Meteorology,
 Climatology, Climate dynamics, Atmospheric Physics and Chemistry, as well as Air Quality and Environmental 
Physics and contain the latest research results in the corresponding fields. We would like to thank the 
Scientific Committee for its valuable efforts during the review process, the Organizing Committee for its 
tireless efforts towards the success of this conference and Conferre, the Congress Secretariat and specifically
 Lina Siamopoulou and Korina Hatzigianni for all of their hard work and perseverance during these rocky times. 
We would also like to acknowledge our sponsors for their support that brought this conference into fruition. 
We wish you all a pleasant stay in Ioannina and a stimulating time at COMECAP 2021

The Chair of the Organizing Committee

Aristides Bartzokas