Meteorological conditions of ice and snow accretion in the southern and central regions of UkraineKhomenko Inna, Odessa State Environmental University, UkraineEuropean Conference on Applications of Meteorology/ EMS Annual Meeting

In order to study conditions of atmospheric icing near the surface such as glaze, soft and hard rime, snow accretion, the data for 39 stations of Ukraine are used for period of 1996-2007.

Database contains temperature, wind speed and wind direction in the beginning of icing accretion and at the moment that the accretion reached maximum in the size.

Odessa regionKherson regionMykolayv regionVinnytsia regionKirovohrad region

Classification of sites according tothe severity of icingcollision efficiency, sticking efficiency, freezing efficiency, liquid water mass/unit volume, wind speed, cross-sectional area of object.(1) (2) Intensity of icing is calculated according the formula (1)after integration of formula (1)we obtained

Classification of sites of Ukraineaccording to the severity of icing

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surfaceGLAZE87%51%In a half of these cases the slightly negativetemperatures are observed from -1 to 0. The most glaze events (about 87%) are connectedwith the narrow negative temperature from 0 to -4 C.

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surfaceHARD RIME82%32%For the hard rime the more widetemperature interval (-8-1) is typical. 32% from these cases are associatedwith temperatures from -6 to -4.

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surfaceSOFT RIME74%58%The soft rime events are distributed almost evenly in the interval -20-6,in which 74% of all the soft rime cases occur. The most cases take place under -16-10 temperature.

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surfaceWET SNOW93%Approximately 90% of the wet snow casesare related with the -1+1 C interval.

Frequency distribution of wind directionin the beginning of atmospheric icing near the surface14%The most number of hard and softrime cases are reported under calm(soft rime 38%, hard rime 25%).

For the hard rime the remaining cases are distributed evenlyin the other graduations. And for the soft rime the north directionwith the highest frequency is obtained.

Frequency distribution of wind directionin the beginning of atmospheric icing near the surface66%60%8%For the glaze surface wind is characterized byhigh occurrence frequency of north, north-east,east and south-east directionsFrequency of the glaze casesunder the calm is significant. with the maximum for north-east and east directions.

Frequency distribution of wind direction at the moment,in which the icing accretion reached maximum in sizeFrequency distribution ofthe wind direction arealmost unchangeablein the duration of accretion of ice.

Frequency of occurrence of glaze in the beginning of the eventas a function air temperature and wind speed

Frequency of occurrence of hard rime in the beginning of the eventas a function air temperature and wind speed

Frequency of occurrence of soft rime in the beginning of the eventas a function air temperature and wind speed

Frequency of occurrence of wet snow in the beginning of the eventas a function air temperature and wind speed

similar technique is applied to the other regions of Ukraine;

application of regression analysis to the wind-temperature plot, obtained for different types of icing, and dividing the icing into different areas by temperature and wind speed for different regions of Ukraine;

classification of the territory of Ukraine, using the site icing index.

The further steps:

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