The relations between North Atlantic Oscillation and minimum temperature in Turkey

Abstract

It has been observed that there is a significant negative correlation between the average temperature values taken from the 32 stations chosen across Turkey and the North Atlantic Oscillation. However, more interestingly the reaction of the stations to the North Atlantic Oscillation and the degree of the significance of the correlations become weaker as we move in a west-east direction. The factors of continentality-oceanity have also obvious effects on the correlation values. This effect is more clearly seen between the temperature values and the atmospheric oscillations. The North Atlantic Oscillation is particularly effective on the temperatures from the stations located in areas where continental climate prevails. On the other hand, this effect is either too weak or gives an insignificant correlation in the stations located in areas where maritime climate prevails.

There isn’t a significant correlation between the temperature values from the stations that are in lower longitudes and the North Atlantic Oscillation. When we take the negative years into account separately from a statistical standpoint, we see that there is a more significant correlation between the North Atlantic Oscillation and the temperature values than that of the positive years. Generally there is a negative correlation between the minimum temperature values of the stations and the index value in those years in which the North Atlantic Oscillation index values are negative. In other words, as the index values of the North Atlantic Oscillation decrease, the minimum temperatures in Turkey increase. The reason for this can be said to be the westerly winds carry a great amount of humid and warm air masses to the Mediterranean basin and make the climate there milder.