We present an analysis of seasonal cycle of the last 50 years of records of
surface temperature in Italy. We consider two data sets which synthesize the
surface temperature fields of Northern and Southern Italy. Such data sets
consist of records of daily maximum and minimum temperature. We compute the
best estimate of the seasonal cycle of the variables considered by adopting the
cyclograms' technique. We observe that in general the minimum temperature cycle
lags behind the maximum temperature cycle, and that the cycles of the Southern
Italy temperatures records lag behind the corresponding cycles referring to
Northern Italy. All seasonal cycles lag considerably behind the solar cycle.
The amplitude and phase of the seasonal cycles do not show any statistically
significant trend in the time interval considered.Comment: 30 pages, 6 figures, submitted to IJ
