List of Articles Climatic indices

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  1 - Analysis of evidence of climate change in southern coast of the Caspian Sea
  Alireza Sadeghinia Mahdi Sedaghat Somayeh Rafati
  In this study, in order to identify the most important evidence of climate change in the southern coast of the Caspian Sea, temperature and precipitation changes were studied using 20 indices during 1968-2017. The results showed that the intensity of precipitation signi More

  In this study, in order to identify the most important evidence of climate change in the southern coast of the Caspian Sea, temperature and precipitation changes were studied using 20 indices during 1968-2017. The results showed that the intensity of precipitation significantly increased, but the number of days with precipitation significantly decreased. Despite the increase in rainfall intensity, the total annual rainfall has decreased, because of the number of rainy days and length of wet periods significantly decreased. Seasonally, spring rainfall decreased and summer rainfall increased. All the extreme temperature indices showed significant trends. On average, the increasing trends of the minimum annual temperatures and maximum annual temperature were 0.51 ° C and 0.31 ° C in per decade, respectively. The frequency of hot days and hot nights significantly increase with an increase rate of 1.5% and 2.7% per decade, respectively. Also, the frequency of cold days and cold nights significantly fell with a decrease rate of 1.1% and 1.3% per decades, respectively. In general, the heating trend of the nights was stronger than during the days. The warm spell duration index showed a clear increase, with a rate of 2.6 d per decade. Comparison of the results of this study with the findings of global studies showed that the increasing trend of temperature in the southern Caspian coast is in line with the trends observed in global studies, but the decreasing trend of precipitation in the Caspian region is opposite to the increasing trend of global precipitation. Manuscript profile
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  2 - Trends in extreme daily temperature in south west of Iran during recent decades
  alireza shakiba einallah khalili amaneh dashtbozorgi
  Long-term annual or seasonal averages of climatic variables like temperature, has generally been used as indicator for the assessment of climate change.  Accordingly, this paper is aimed to examine extreme temperature as indicative climatic variable in synoptic sta More

  Long-term annual or seasonal averages of climatic variables like temperature, has generally been used as indicator for the assessment of climate change.  Accordingly, this paper is aimed to examine extreme temperature as indicative climatic variable in synoptic stations of Ahwaz located in Khozestan province during a 40 year period (1964- 2003) to determine recent climatic changes over the mentioned area. To achieve the aim, 6 indices of extreme temperature recommended by the internationally agreed WMO–CCL/CLIVAR list of over 50 climate change indices climate extremes were selected and calculated. The six indices are consist of  cold nights, cold days, warm nights, hot days, summer days and diurnal temperature range. These indices describe cold extremes as well as warm extremes. Extreme temperature indices for this study are based on the 1st and 99th percentiles. According to the current climate condition, based on ARIMA model, 10 years prediction of mentioned indices also was made.  The results of the research indicated that thermal conditions over the area are changing as indicated by a warming trend identified during the study period. The results also shown the marked negative trends for indices such as cold days, cold nights and diurnal temperature range over the region. While significant increases are detected in the annual number of hot days, warm nights and summer days. The output of ARIMA model confirmed consist warming trend for Ahwaz in the next 10 years (2004-2013). Manuscript profile
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  3 - Drought Monitoring Using Climatic Indices and Geostatistic Technique (Case Study: Hossein Abad Plain, Sarbisheh, Iran)
  H Ghasemi A.A Gholami GH.R Hadarbadi H Ebrahimi
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