caa a22 4500 467937591 CHVBK 20180406153001.0 cr unu---uuuuu 170328e20061101xx s 000 0 eng 10.1007/s00703-006-0190-y doi (NATIONALLICENCE)springer-10.1007/s00703-006-0190-y The role of the subtropical jet stream during heat wave events over north-central Greece [Elektronische Daten] [D. P. Brikas, T. S. Karacostas, P. J. Pennas, A. A. Flocas] Summary: The role of the subtropical jet stream (SJ) in the occurrence of heat waves in South Balkans and Greece is sought here. For this purpose ECMWF grid-point data is examined, concerning the Balkan heat wave of 5-9 July 1988, that cost human lifes, at least in Greece. For the city of Thessaloniki, Greece, a temperature budget is presented, as a function of time. It turns out that the most important heating mechanism is the adiabatic heating. Horizontal mass convergence at the maximum wind level (200 hPa) causes descent and adiabatic heating. The convergence occurs in association with the Hadley Cell, as well as with the right exit quadrant of an anticyclonically curved subtropical jet streak. As air parcels that exit the above jet streak slow down and turn anticyclonically, a strong ageostrophic wind current is established towards and to the right of the flow direction. This ageostrophic current converges above the northeastern Balkans. Downward ageostrophic motion emerges from the above area of horizontal convergence and heads towards the SSW, affecting the Balkans. From the above case study, it is concluded that intense heat waves are favoured in the South Balkans and Greece when the SJ is anticyclonically curved to the north of the Balkans and a jet streak is situated to the north west of the Balkans. Springer-Verlag, 2006 Brikas D. P. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut Karacostas T. S. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut Pennas P. J. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut Flocas A. A. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut Meteorology and Atmospheric Physics Springer-Verlag 94/1-4(2006-11-01), 219-233 0177-7971 94:1-4<219 2006 94 703 https://doi.org/10.1007/s00703-006-0190-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00703-006-0190-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Brikas D. P. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut NATIONALLICENCE 700 1- Karacostas T. S. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut NATIONALLICENCE 700 1- Pennas P. J. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut NATIONALLICENCE 700 1- Flocas A. A. Department of Meteorology and Climatology, Aristotelian University of Thessaloniki, Greece aut NATIONALLICENCE 773 0- Meteorology and Atmospheric Physics Springer-Verlag 94/1-4(2006-11-01), 219-233 0177-7971 94:1-4<219 2006 94 703 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer