The Relationships between the Number of Sunspots and Fluctuation in the Trend of Climatic Components in Iranduring Recent Decades

The statistical period from 1951 to 2005 was chosen in this research for determining the extent of influence on precipitation and annual temperature from sunspots. This analysis was conducted on 31 synoptic stations in Iran. Initially, the Mann-Kendall test was administered in order to analyze the trend of alterations of these two components over time and the results suggest that 16% of the stations show significant relationship with annual precipitation (positive and negative). More stations showed significant relationships between sunspots and minimum annual temperature (74.19%), maximum annual temperature (48.38%) and mean annual temperature (67.8%). The amounts of the above correlations include all of the significant trends, whether those that show inverse significant trends or those that demonstrate direct significant trends. For further investigating the relationship between variations in the number of sunspots and temperature, 5 temporal ranges were used. This analysis was conducted on raw data (without a moving average) and also on data with a moving average of 5, 8, 11 and 22 years. The general conclusion drawn from different temporal ranges of precipitation data was that a significant amplification for Iran’s stations with a frequency coefficient of 25.16% was observed. However, when this relationship is reversed, the frequency the coefficient turned out to be 12.92.Likewise, for different components of temperature, the inverse relationship between the number of sunspots and alterations of temperature possesses a higher frequency position among the stations. This value is 15.46 % for the minimum temperature, 16.12% for the maximum and 12.89% for the annual average temperature.