The influence of the East Atlantic Oscillation to climate indices based on the daily minimum temperatures in Serbia

In this study, the influence of the East Atlantic Oscillation (EAO) on the climate indices based on the daily minimum temperature at eight stations in Serbia was examined. The following climate indices were analyzed: frost days (FD), cold nights (TN10p), warm nights (TN90p), minimum value of daily minimum temperature (TNn), tropical nights (TR), and cold spell duration indice (CSDI). Analysis of correlation between the East Atlantic Index (EAI) and the geopotential at 500 hPa, as well as between the EAI and climate indices was realized for all seasons and months during the period 1950–2009. Two characteristic situations for the extreme positive and negative values of the EAI were analyzed. Seasonal and monthly trend analyses of climate indices were performed. Decreases of FD and TN10p and increases of TN90p and TR were observed. It was found that the negative correlation prevailed between the EAI and TN10p/FD, and positive one between the EAI and TN90p/TR for all seasons and months. The highest correlation was observed between the EAI and TN90p in February.