نویسنده
دانشگاه زنجان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسنده [English]
In this paper we attempt to investigate potentials of temperature estates for prediction of precipitation stance âbased on conditional probability. For this purpose the daily precipitation and temperature of Iran data base are âused. This database has been established using 1436 stations for precipitation measurements as well as 664 âstations for temperatureâs over Iran during1961/3/21 to 2004/12/31 and 15Ã 15 KM resolution. Accordingly it âhas created 7187 pixels all over Iran. All calculations have been accomplished on these pixels. Probability âdistributions of each pixel and their 25 and 75 percentiles of temperature have been estimated. Based on this âclassification the cold, moderate and hot days have been defined as well as the no precipitation, low âprecipitation and high precipitation days based on mean of probability distribution in each pixel. The join and âconditional probability have been calculated for every pixel to show every attitude of precipitation in compare to âone day previous. The results showed the precipitation â temperature relationship has tempo-spatial patterns âthat cause very uncertainty in forecasting. However each day precipitation prediction based on previous day is âmore probable in compare with later days. In some places such as southern coasts high precipitation is more âprobable after a cold day. Meanwhile the dry days is more probable after a cold day in northwest of Iran as well âas in north of Hormoz strait, Khozestan coasts and Sistan region. No precipitation day after moderate day is âprobable in 80% of times in south and north of Khozestan, from west of Hormoz strain to Baloochestan.â
کلیدواژهها [English]