تغییرات و ساختار فضایی فصلی تابش موج بلند خروجی ایران

تغییرات در تابش موج بلند خروجی زمین به عنوان یک شاخص حیاتی سینوپتیکی دگرگونی و مخاطرات آب و هوایی است که برای شناسایی کمربند خشک گرمسیری، چرخش سلول هادلی، نوسانات اقیانوسیجو، ابرهای ضخیم و همرفتی، پیش بینی زلزله و گردوغبار در نظر گرفته می شود؛ هدف از این مطالعه بررسی تغییرات فصلی تابش موج بلند خروجی ایران می باشد. بدین منظور داده های تابش موج بلند خروجی زمین طی دوره آماری 13961354 از پایگاه داده ncep/ncar استخراج و مورد تجزیه تحلیل قرار گرفت. یافته ها نشان داد تابش موج بلند خروجی ایران به نسبت افزایش هر سال، به مقدار w/m2 16/0+ افزایش و همچنین، با افزایش عرض جغرافیایی به مقدار w/m2 37/0 کاهش می یابد. روند تغییرات فصلی بیانگر این است که 100درصد مساحت کشور در فصل زمستان از روند افزایشی معنی داری و در فصل پاییز عدم معنی داری برخوردار بوده است. فصل تابستان 24/21 درصد و در بهار 35/18 درصد از روند کاهشی عدم معنی داری برخوردار است که در جنوب شرق شامل استانهای سیستان و بلوچستان، کرمان، فارس و هرمزگان است و همچنین 76/78 درصد فصل تابستان و 65/81 درصد فصل بهار از روند افزایشی عدم معنی داری برخوردار می باشد. بررسی شاخص فضایی آماره gi لکه های داغ تابش موج بلند خروجی ایران در فصل های بهار، پاییز و زمستان در جنوب و جنوب شرق کشور شامل استانهای سیستان و بلوچستان، هرمزگان، کرمان، جنوب فارس، بوشهر و در فصل تابستان در مرکز ایران شامل دشت های لوت، کویر و صحرای پست نمک زار و ماسه زار طبس و همچنین در غرب ایران در استانهای کرمانشاه، خوزستان و ایلام با مرکزیت موسیان مشاهده شده است.مناطق لکه های سرد در همه فصول به صورت کمربندی از شمال شرق به سوی شمال غرب و همچنین در زاگرس شمالی مشاهده شده است که کمینه آن با میانگین w/m2220 213 به مرکزیت خوی، ماکو، چالدران، جلفا و مرند است.

Study changes and spatial pattern seasonal of outgoing long wave radiation in IRAN

Study changes and spatial pattern seasonal of outgoing long wave radiation in IRAN IntroductionChanges in OLR can be considered as a critical indicator of climate change and hazard; studies have shown that since 1985, longrange radiation has increased the output of the Earth and is a cause of increased heat in the troposphere. This has led to an increase in drought and a slight decrease in the cloud in the upper terposphere, as well as an increase in Hadleychr('39')s rotation toward higher latitudes. On the other hand, clouds play an important role in the longwave changes of the Earthchr('39')s output and are adequately evaluated at the global energy scale at all spatial and temporal scales.Data and methodsIn the present study, in order to calculate the variability and the pattern of seasonal spatial dependence of the longrange radiation output of Iran, OLR data from 1974 to 1976 were daily updated from the NCEP / NCAR databases of the National Oceanic and Oceanographic Organization of the United States of America. To calculate Iranchr('39')s longrange output radiation, in the Iranian atmosphere (from 25 to 40 degrees north and 42.5 to 65 degrees east), using Grads and GIS software. First, the general characteristics of the earthchr('39')s long wave were investigated. To obtain an overview of the spatial status of the seasonal changes of the longwave and its variability over the country, the average maps and coefficients of the longwave variations of the earthchr('39')s output were plotted in the spring, summer, fall, and winter seasons. In this study, the slope of linear regression methods using mini tab software was used for trend analysis. Hotspot analysis uses GetisOrd Gi statistics for all the data.Explaining the resultsThe results of this study showed that the mean of long wave in Iran is 262.3 W/m2. The highest mean longrange radiation output in spring, autumn, and winter is related to latitudes below 30 degrees north, especially in the south and southeast of Iran, with the highest mean in autumn and winter with wavelengths. High output 282274 W/m2 as well as spring with mean W/m2 295291 below latitude 27.5 ° C, which is in Sistan and Baluchestan provinces, south and southeast of Fars. Hormozgan has also been observed; the lowest OLR average in these seasons is observed above latitude 30 ° N in the northwestern provinces with the lowest mean in the season Yew and winter with mean long wavelength output 213225 W/m2 and also observed in spring with mean 226235 W/m2 at latitude 37.5 ° C and latitude 44 ° N in Maku and Chaldaran Is. In summer, the highest OLR averages of 316307 W/m2 are observed in east of Iran with centralization of Zabol, Kavir plain and Tabas desert as well as west of Iran in Kermanshah, Khuzestan and Ilam provinces, with central length The latitude is 47.50 degrees north and latitude 32/32 east in Ilam province in the city of Musian, due to desertification, saltwater and sand, as well as the absence of high clouds, indicating an increase in the frequency of earthquakes and It is a drought that will lead to shortage of rainfall and increased rainfall in these areas; the lowest average longrange radiation output in summer with W/m2 235226 extends as a narrow strip from southeast to Chabahar and extends to the middle Zagros highlands in Chaharmahal Bakhtiari province and northwest areas in Maku, Chaldaran, Khoi, Jolfa, Marand, Varzegan, Kalibar, Parsabad, Ahar and Grammy cities. It has also been observed in the northern coastal provinces of Iran including Mazandaran, Gilan, Astara, Talesh, Namin. According to the trend of longwave radiation output of Iran increased by 0.16 W/m2 and decreased by 0.37 W / m2 with increasing latitude. Seasonal trends indicate that 100 percent of the country has a significant increase in winter and no significant fall in autumn. 21.24% in summer and 18.35% in spring have no significant decreasing trend, which in southeast includes Sistan and Baluchestan, Kerman, Fars and Hormozgan provinces and 78.76% in summer and 81.65% in summer. Spring has a significant nonsignificant upward trend. The spatial dependence of the hot spots on Iranchr('39')s longwave radiation at 90, 95 and 99% confidence levels is 45.49% in spring, 37.57 in autumn, and 44.55% in winter. The high wave radiation of summer is 42.2%, which is observed in north of Sistan and Baluchestan province with central Zabul and in east of Lot and Tabas desert and in west of Ilam province with central of Musian. But in spring, autumn and winter in the south and southeast of the country including Sistan and Baluchestan, Hormozgan, Kerman, South Fars, Bushehr provinces and in central Iran including Lot Plains, Desert and Salt Lake and Tabas sandy desert. It is also observed in western Iran in Ilam province, so that these areas correspond to the tropical belt at latitude 30 degrees north. This is due to its location in the subtropical region, the low latitude of Iran, especially south and southeast to central Iran including Lut Plain, Desert and Tabas Desert due to its proximity to the equator, the angle of sunlight is higher and perpendicular. Spun. The spatial dependence of cold spots on longwave radiation at 90, 95 and 99% confidence levels in spring is 33.44%, autumn is 41.41% and in winter is 44.55%. Cold spots of longwave radiation are 25.5% in the summer, located at latitudes above 35 ° N in the subtropical belt and include northeast areas in North Khorasan Province in the cities of Bojnourd, Esfarain, Jajarm, Mane and Semlaghan, Safi Abad and northern coastal areas in Golestan, Mazandaran, Guilan, and northwestern provinces of Iran including Ardabil, East and West Azerbaijan, Qazvin and Zanjan North Tfaat Kvh not;Hay Zagros includes the provinces of Kurdistan, Hamedan, Markazi, Qom, Kermanshah North East part. Minimum OLR cold spot with average output longwave radiation of 213 W/m2 220 northwest of Khoy, Maku, Chaldaran, Jolfa and Marand can be an indicative role for determining convective activity and dynamic / frontal precipitation.Keywords: Temporal and Spatial VariationsOLRSpatial Index of Statistics Gi.