خورشید منبع بنیادی انرژی در سامانۀ اقلیمی زمین است و تغییرات آن نوساناتی را در جوّ زمین ایجاد میکند. شرایط آب و هوایی مناطق مختلف در ارتباط با فعالیتهای خورشیدی است و این فعالیتها یکی از دلایل رخدادهایی مانند خشکسالیها و سیلابهاست. پژوهش حاضر با هدف بررسی تأثیر فعالیت لکههای خورشیدی بر دمای حداقل ماهانۀ استان اصفهان و به شیوۀ پیکسلی صورت پذیرفته است. در این راستا از آمار دمای حداقل 21 ایستگاه همدید و آب و هواشناسی در داخل و خارج استان طی مقطع زمانی 2010-1961 و همچنین آمار تعداد لکههای خورشیدی طی همان دوره بهره گرفته شد. پس از اطمینان از همگنبودن دادههای مورد مطالعه با آزمون Runs Test، دادههای ایستگاهی با میانیابی به دادههای پیکسلی با ابعاد 5×5 کیلومتر مربع تبدیل شد. سپس ارتباطسنجی عناصر مورد مطالعه با روش تحلیل موجک پیوسته مورلت و تحلیل موجک متقاطع انجام گرفت. نتایج حاصل از این پژوهش بیانگر آن است که دمای حداقل استان اصفهان از چرخههای زمانی 4-1 و 11-8 ساله برخوردار بوده است که همزمان با فعالیت لکههای خورشیدی است. بهخصوص در ماه دسامبر که چرخههای زمانی 11-8 ساله رخ داده و از نمود بیشتری برخوردار است. همچنین بجز ماه فوریه که ارتباط و همبستگی عناصر مورد مطالعه از نوع منفی است، در سایر ماهها همبستگی مشاهدهشده از نوع همفاز و مثبت معنادار بوده است.
عنوان مقاله [English]
Correlation between sunspot activity and temperature measurement at Isfahan province based on wavelet analysis
1- Introduction The sun is the primary source of all energy in the climate system is derived and so it is clear that changes in solar output can affect the Earth 's climate .The most important and most obvious indicator that expresses the variation of solar variability is a variable number of black spots on its surface(Friis-Christensen, 2000). In a recent study to measure solar activity is used parameters such as sunspot number, sunspot area ratio and area (Hoyt, 1979) and the length of sunspot cycles (Christensen and Lassen, 1991). The importance of this phenomenon in the variation of the sun's surface variability and its impact on Earth 's climate and atmospheric phenomena provides an. 2- Materials and Methods To achieve the effect of sunspot activity to a minimum temperature of Isfahan, is required data at the provincial level and the minimum temperature of sunspots. In this regard, were used the minimum temperature data from 16 synoptic stations and 5 stations for better coverage of climatology within the province and outside the province during the period 2010-1961.Data on the number of sunspots was prepared from the geophysical America (NGDC). were studied the minimum temperature in the discussion of data analysis and data homogeneity test, Runs test subjects. Then, according to this study, the data station with surfer software interpolation method kriging the pixel data with dimensions of 5 × 5 km into. It is also a test to measure the pixel size of 5 × 5 graphics were used and were recognized as the most appropriate dimensions.Then remove pixels outside the boundaries of the province , and finally 4260 pixels , which covered the range further studies remained . Resulting in more pixels and the average pixel separation of each month every month for the poll associated with sunspots, respectively. Matlab software was performed then polls the relationship between the pixels of Isfahan Province and the sunspot minimum temperature with continuous wavelet analysis Morlt cross wavelet analysis. 3 - Discussion According to the results of the analysis of continuous wavelet obvious during January 8 to 11 -year cycle of sunspots can be seen in all the years studied . While the typical cycle of 2 to 5 years , there are temperature variations during 1961-1968 . The arrows also indicate that changes in temperature and sunspot January Isfahan significant at all levels and phases (correlation ) are positive so that increases the number of sunspots , also increased in temperature at night . February temperature cycles 1 to 4 years in the years 1970-1975 and sub-cycle is 2 to 3 years during 2008-2010. During March 2 to 4 year cycle has been observed during the years 1975-1985. Cross- wavelet analysis of survey results also indicate that the most significant in a cycle of 8 to 12 years during 1978-1990 and secondary cycles 1 to 3 years and 1 to 4 years during 1965 to 1970 and from 1975 to 1985 has appeared . In April cycles Cycle 1 year 1 to 2 years of age in 1981 and has over the years 2010-2007. In May, there is three cycles of one year during 1980, 1985 and 1990. During June, 1 to 4-year cycle is observed during the period 1965-1970. The continuous wavelet analysis in August during the years 1960-1970 and night temperature cycles from 1 to 4 years old and has had a significant level higher than 5%. Continuous wavelet analysis in September indicates that the temperature changes during the years 1988-1995 in the province of sunspots in cycle 1 to 4 years of age has a significant correlation . In October, 1 to 4-year cycle in the period 1961-1975 in Isfahan has been observed temperature changes. During November, marked 1 to 4 -year cycles during the years 1962-1970 at the 5 % significance level and sub- cycles 2 to 4 years of age during the years 1980 to 1982 have occurred at night, Isfahan province . In December, the night temperature cycle of sunspot activity coincided with a marked 8 to 11 years during 1965 to 1990 and from 1 to 4 -year secondary cycle occurred from 1961 to 1967 years . 4- Conclusion Continuous wavelet analysis of the survey results suggests that Morlt minimum temperature changes in Isfahan has positive and significant cyclical fluctuations during cycles 1 to 4 years is that sunspot activity is coordinated .The cycles are typically have been observed between the years 1965-1970, 1970-1975 and 1975-1980. It cycles through the cold months can be more So that during December, when have occurred two cycles 1 to 4 and 8 to 11 years old during the period 1961 to 1990. In contrast, during the hot months when fewer cycles observed in the months of April and May and the minimum temperature of the cycle has been remarkable . Using the wavelet cross-correlation analysis revealed a strong correlation between the parameters studied. The results of this analysis is indicate a significant positive correlation between temperature and sunspot minimum. It cycles between cycles when the minimum temperature is generally 8 to 11 years And secondary cycles 1 to 4 years , which is occurred concurrently with increased sunspot activity. Cross wavelet analysis as a continuous wavelet analysis results in the cold months of December was particularly further So that the cycle of 8 months to 11 years were studied in statistical terms . Also according to the direction of the arrow can be stated that all of the observed correlation is positive phase except in February, has occurred a significant negative correlation.