آشکارش جبهه‌های دمایی ساحلی خلیج فارس و دریای عمان با استفاده از تصاویر مودیس

ﺟﺒﻬﻪﻫﺎی دﻣﺎﯾﯽ از اﻫﻤﯿﺖ ﺑﺎﻻﯾﯽ در ﻣﻄﺎﻟﻌﺎت درﯾﺎﯾﯽ ﺑﺮﺧﻮردارﻧﺪ. ﺟﺒﻬﻪﻫﺎ ﻣﻨﺎﻃﻖ ﺑﺎرﯾﮑﯽ ﻫﺴﺘﻨﺪ ﮐﻪ ﺑﻪﻋﻠﺖ اﺧﺘﻼف در ﭼﮕﺎﻟﯽ، ﺷﻮری ﯾﺎ دﻣﺎ در ﻣﺮز ﺑﯿﻦ دو ﺗﻮده ی آب ﺗﺸﮑﯿﻞ ﻣﯽﺷﻮﻧﺪ. در اﯾﻦ ﭘﮋوﻫﺶ، ﺑﺎ اﺳﺘﻔﺎده از داده ﻫﺎی دﻣﺎی ﺳﻄﺢ درﯾﺎی ﻣﺎﻫﻮاره ی ﻣﻮدﯾﺲ ﺑﻪﺻﻮرت ﻣﺎﻫﺎﻧﻪ از 2013 ﺗﺎ 2014، ﺑﺎ اﻋﻤﺎل اﻟﮕﻮرﯾﺘﻢ ﺷﻨﺎﺳﺎﯾﯽ ﻟﺒﻪای ﮐﻨﯽ2، ﺟﺒﻬﻪﻫﺎی دﻣﺎﯾﯽ ﺣﻮاﻟﯽ ﺳﺎﺣﻞ در درﯾﺎی ﻋﻤﺎن و ﺧﻠﯿﺞ ﻓﺎرس ﺷﻨﺎﺳﺎﯾﯽ ﺷﺪﻧﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن دادﻧﺪ ﮐﻪ ﺣﻀﻮر ﺟﺒﻬﻪﻫﺎ در ﻣﺎه ﻫﺎی ﭘﺎﯾﯿﺰی november ،october و december و ﻧﯿﺰ ﻣﺎه ﻫﺎی january و may در 2013 و در ﻣﺎهﻫﺎی november ،january و december در 2014 در ﺟﻨﻮب اﯾﺮان ﻣﺤﺴﻮسﺗﺮ اﺳﺖ. در درﯾﺎی ﻋﻤﺎن ﺑﻪ ﻋﻠﺖ ﻣﻮﻧﺴﻮن زﻣﺴﺘﺎﻧﯽ در ﻣﺎهﻫﺎی ﺳﺮد ﺳﺎل january ،december و february ﺗﻌﺪاد ﺟﺒﻬﻪﻫﺎ ﺣﺪاﻗﻞ و ﺑﻪﻋﻠﺖ ﻣﻮﻧﺴﻮن ﺗﺎﺑﺴﺘﺎﻧﯽ در ﻣﺎهﻫﺎی ﮔﺮم ﺳﺎل ﯾﻌﻨﯽjuly ،june و august ﺗﻌﺪاد ﺟﺒﻬﻪﻫﺎ ﺣﺪاﮐﺜﺮ اﺳﺖ. ﻫﻤﭽﻨﯿﻦ ﺟﺒﻬﻪ ی ﭘﺎﯾﺪار و ﻣﻨﺴﺠﻤﯽ در ﻧﺰدﯾﮑﯽ اروﻧﺪرود در ﺧﻠﯿﺞ ﻓﺎرس دﯾﺪه ﺷﺪ ﮐﻪ ﺣﻀﻮرش در ﻣﺎه ﻫﺎی ﺳﺮد ﺳﺎل ﺑﯿﺸﺘﺮ اﺳﺖ. در ﻣﺎه ﻫﺎی august ،july و april اﯾﻦ ﺟﺒﻬﻪ ﺗﻘﺮﯾﺒﺎ ﻧﺎﭘﺪﯾﺪ ﻣﯽﺷﻮد. ﺟﺒﻬﻪی ﭘﺎﯾﺪار دﯾﮕﺮ ﻧﯿﺰ در درﯾﺎی ﻋﻤﺎن و در ﺟﻨﻮب ﭘﺎﮐﺴﺘﺎن ﺷﻨﺎﺳﺎﯾﯽ ﺷﺪ. ﺑﯿﺸﺘﺮﯾﻦ ﺣﻀﻮر اﯾﻦ ﺟﺒﻬﻪ در 2013 در ﻣﺎهﻫﺎی ﮔﺮم october ،september ،june و may و در 2014 درaugust ،june و october اﺳﺖ.

Detection coastal fronts in Oman and persian gulf with canny algorithm

For this study different time series of MODIS level3 thermal IR SST data from 20132014 has been processed and thermal fronts the of Persian Gulf and the Oman Sea (47.6°E to 67.7°E and 18°N to 31°N) region mapped using the method, the Canny algorithm and Gaussian filter. Monthly thermal front images of this region are mapped during the period of January 2013 to June 2014 are classified into Summer Monsoon (June, July, August, September), Winter Monsoon (October, November, December, January) and Pre Monsoon (February, March, April, May) periods and their characteristics are discussed here. The results show that high frequency of SST fronts were observed in the Oman Sea and Persian Gulf in October, November, December, January and May in 2013 year and January, November and December in 2014 year. The number of fronts increases since the beginning of winter to early spring and the beginning of fall, too. The remaining these fronts move with current toward the Arabian Sea and Indian Ocean at the beginning of the summer monsoon. Sustainable and cohesive front was seen near the Arvand River in the Persian Gulf that is presents in the cold months more. This front will disappear in the months of July, August and April 2013 and 2014. The other stable front is in the Oman Sea in southern Afghanistan. Most of the front are presenting in the warmer months of June, September, October in 2013 and in June, August and October in 2014.