Multiscale analysis of lake-effect snow over the southwest coast of the Caspian Sea (31 January-5 February 2014)
Ghafarian, Parvin ; Pegahfar, Nafiseh ; Owlad, Elaheh
Année de publication
An extreme heavy snowfall event occurred over the southwest coast of the Caspian Sea over the period 31 January-5 February 2014 and caused huge economic losses to both the government and the people of Iran. This phenomenon has been analysed using in-situ data and AVHRR satellite data, as well as NCEP/NCAR and GFSANL reanalysis data. The results indicate that a cold-air outbreak from Scandinavia to the Caspian Sea provided an appropriate synoptic pattern for the passage of cold air over the warm lake. In addition, the existence of an omega blocking system at medium levels (~500hPa) over Europe resulted in the persistence of this synoptic system. Furthermore, favourable conditions such as thermal instability, long fetch and low directional wind shear caused this lake-effect snow (LES). Finally, the Alborz Mountains and the form of the southwest coast of the Caspian Sea were also found to have a particular role in the formation of LES in this region.