پديد آورندگان :
عابدي, فاطمه دانشگاه اصفهان , رحيمي, داريوش دانشگاه اصفهان , مسعوديان, ابوالفضل دانشگاه اصفهان
چكيده فارسي :
ﺳﺎﻣﺎﻧﻪ ﻫﺎي ﺑﻨﺪاﻟﯽ ﺑﻪ ﻋﻨﻮان ﯾﮏ ﭘﺪﯾﺪة ﻫﻤﺪﯾﺪ، ﺗﺄﺛﯿﺮ زﯾﺎدي ﺑﺮ ﻧﻮﺳﺎن ﺳﺎﯾﺮ ﻋﻨﺎﺻﺮ اﻗﻠﯿﻤﯽ ﺑﻪ وﯾﮋه دﻣﺎ و ﺑﺎرش دارﻧﺪ. ازاﯾﻦ رو در اﯾﻦ ﭘﮋوﻫﺶ، آﺷﮑﺎرﺳﺎزي روﻧﺪ ﺗﻐﯿﯿﺮات ﺳﺎﻣﺎﻧﻪ ﻫﺎي ﺑﻨﺪاﻟﯽ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. ﻧﺨﺴﺖ ﺳﺎﻣﺎﻧﻪ ﻫﺎي ﺑﻨﺪاﻟﯽ ﺑﺎ ﻧﻤﺎﯾﮥ TM در دورة 1951-2012 و ﺗﻔﮑﯿﮏ زﻣﺎﻧﯽ 6 ﺳﺎﻋﺘﻪ و ﺗﻔﮑﯿﮏ ﻣﮑﺎﻧﯽ 2/5 ×˚2/5 ﺟﻐﺮاﻓﯿﺎﯾﯽ ﺑﺮاي ﺗﺮاز 500 ﻫﮑﺘﻮﭘﺎﺳﮑﺎل ﺷﻨﺎﺳﺎﯾﯽ و ﻓﺮاواﻧﯽ آن ﻫﺎ در ﺗﺪاوم ﻫﺎي 1 ﺗﺎ 47 ﻣﺸﺎﻫﺪه اي ﻣﺸﺨﺺ ﺷﺪ. ﺳﭙﺲ ﺑﺎ ﮐﻤﮏ آزﻣﻮن ﻧﺎﭘﺎراﻣﺘﺮي ﻣﻦ-ﮐﻨﺪال روﻧﺪ ﺗﻐﯿﯿﺮات آن ﻫﺎ ﺷﻨﺎﺳﺎﯾﯽ ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﻓﺮاواﻧﯽ رﺧﺪاد ﺳﺎﻣﺎﻧﻪ ﻫﺎي ﺑﻨﺪاﻟﯽ در اﻗﯿﺎﻧﻮس آرام، اروﭘﺎ، آﺳﯿﺎ و اﯾﺮان، روﻧﺪ اﻓﺰاﯾﺸﯽ و در اﻗﯿﺎﻧﻮس اﻃﻠﺲ و آﻣﺮﯾﮑﺎ روﻧﺪ ﮐﺎﻫﺸﯽ دارد. اﯾﻦ روﻧﺪﻫﺎ در 51 ﻃﻮل ﺟﻐﺮاﻓﯿﺎﯾﯽ ﺑﺎ ﺗﺪاوم ﻫﺎي 1 ﺗﺎ 8 ﻣﺸﺎﻫﺪه اي، روﻧﺪ ﻣﻌﻨﺎداري داﺷﺘﻪ ﮐﻪ از اﯾﻦ ﻣﺠﻤﻮﻋﻪ در 26 ﻃﻮل روﻧﺪ ﻣﺜﺒﺖ و در 25 ﻃﻮل روﻧﺪ ﻣﻨﻔﯽ اﺳﺖ. ﻫﻤﭽﻨﯿﻦ ﻧﺘﺎﯾﺞ روﻧﺪﯾﺎﺑﯽ ﻓﺼﻠﯽ، ﺑﯿﺎﻧﮕﺮ ﻣﻌﻨﺎداري اﯾﻦ رﺧﺪادﻫﺎ در7 ﻣﺎه از ژوﺋﻦ ﺗﺎ اﮐﺘﺒﺮ، دﺳﺎﻣﺒﺮ و ﻣﺎرس، ﺻ ﺮ ﻓ ﺎ ً ﺑﺮ ر و ي ﺑﺮ ﺧ ﯽ از ﻃﻮل ﻫﺎي ﺟﻐﺮاﻓﯿﺎﯾﯽ در ﻣﺤﺪوده ﻫﺎي اﻃﻠﺲ، آرام و آﻣﺮﯾﮑﺎ اﺳﺖ ﮐﻪ در ﻣﺤﺪودة اﻃﻠﺲ در ﻣﺎه ﻫﺎي ژوﺋﻦ، ﺳﭙﺘﺎﻣﺒﺮ و دﺳﺎﻣﺒﺮ روﻧﺪ ﮐﺎﻫﺸﯽ و در اﮐﺘﺒﺮ و ﻣﺎرس روﻧﺪ اﻓﺰاﯾﺸﯽ، در ﻣﺤﺪودة آﻣﺮﯾﮑﺎ در ﻣﺎه ﻫﺎي ژوﺋﻦ، ﺟﻮﻻي، ﺳﭙﺘﺎﻣﺒﺮ و اﮐﺘﺒﺮ روﻧﺪ ﮐﺎﻫﺸﯽ و در ﻣﺤﺪودة آرام در ﻣﺎه ﻫﺎي ﺟﻮﻻي ﺗﺎ اﮐﺘﺒﺮ روﻧﺪ اﻓﺰاﯾﺸﯽ ﻣﺸﺎﻫﺪه ﺷﺪ. در اروﭘﺎ، آﺳﯿﺎ و اﯾﺮان ﻧﯿﺰ ﺑﯿﺸﺘﺮ ﻣﺎه ﻫﺎ روﻧﺪﻫﺎي اﻓﺰاﯾﺸﯽ داﺷﺘﻨﺪ، وﻟﯽ ﺑﺮ روي ﻫﯿﭻ ﯾﮏ از ﻃﻮل ﻫﺎي ﺟﻐﺮاﻓﯿﺎﯾﯽ، روﻧﺪ ﻣﻌﻨﺎداري ﻣﺸﺎﻫﺪه ﻧﺸﺪ
چكيده لاتين :
Blocking is one of the most protruding flow patterns and has received attention during the last decades due to its effect on seasonal weather characteristics. Moreover, finding show that Most of the blocking systems in the northern hemisphere are in all seasons and their continuity in the Atlantic and Pacific.
The results of the Mann-Kandal test at the 95% confidence level of the percentage of frequency of blocking systems showed that the northern hemisphere blocking systems have been increasing in most parts of Asia-Pacific, Europe and Iran, and the trend is decreasing on the Atlantic Ocean and the American continental. Of course, these trends only increased significantly on parts of Central Asia and Central Pacific. In the monthly, the Eastern and Central Atlantic segregated from May to September and December the decreasing trend that decreasing only in June, September and December in some areas of the trend, in October, November January, February and March is an increasing, and only in October and March this trend is significant.In the Pacific, except in March, there has been an increasing trend in all months in July, August, October and September. In the Americas, except in May and August, there has been a significant decrease in the other months. In Europe, except for the months of August, September and December, in other month has an increasing trend, which has not been significant. In Asia and in the region of Iran, although it is more or less an increasing trend, it is not significant
