مخاطرات محیط طبیعی (May 2013)
Evaluation Of Changes In Extreme Temperature Indices Over The Kurdistan Province During Last Half Century
Abstract
To doing this research, daily minimum and maximum temperature data from 11 synoptic stations and 15 climatology stations on the in and out of Kurdistan province during 1/1/1962 to 31/12/2010 have been used. Data interpolated on 6 by Kriging interpolation method. The 811 pixels obtained that cover the whole of the province. Two data base in 17898 811 pixels have been created that located days on the rows and pixels on the columns. The 16 extreme temperature indices of Expert Team of Climate Change Detection and Indices (ETCCDI) have been used. For each pixel the 16 indices calculated and evaluated significant trend by non-parametric Mann-Kendal method in the 95% confidence level. The trend slope estimated by liner regression. To doing spatial analysis, the trend and slope rate changes for each indices have been shown in separate maps. The results of this study showed that extreme warm indices are increasing over the low lands and extreme cold indices are decreasing over the heights and mountains. The positive trend for extreme warm indices observed in the west, southwestern and semi-eastern parts of the province. The spatial extent of increasing warm nights is more than warm days. The cold extremes are increasing on the heights and decreasing over the low lands and floor plains. The durnal temperature range(DTR) has been decreased. The changes rate of extreme minimum temperature is more than daily extreme temperature changes.
Keywords