@article { author = {Zarrin, Azar and dadashi-rodbari, abbasali and Salehabadi, Narges}, title = {Projected temperature anomalies and trends in different climate zones in Iran based on CMIP6}, journal = {Iranian Journal of Geophysics}, volume = {15}, number = {1}, pages = {35-54}, year = {2021}, publisher = {Iranian Geophysical Society}, issn = {2008-0336}, eissn = {2783-168X}, doi = {10.30499/ijg.2020.249997.1292}, abstract = {Climate change is a major challenge for human society and the natural environment. Evidence suggests that human activities play a role in increasing temperature at various temporal-spatial scales. The effects of climate change can be assessed by analyzing air temperature trends. According to the latest IPCC report, global average temperatures will increase by 1.5 degrees Celsius by the end of this century. The main purpose of this study is to assess CMIP6 projected temperature over different climate zones of Iran and its trend in the future. The result of this study can be useful for a wide range of management areas, especially the study of water resources, snow reserves, agriculture, and tourism.    In this study, the mean annual temperature data of 43 synoptic stations of the Iran Meteorological Organization (IRIMO) were obtained from 1990 to 2009. To evaluate the anomaly and temperature trend in Iran until the end of the 21st century, the data of three models BCC-CSM2-MR, CAMS-CSM1-0, and MRI-ESM2-0 of CMIP6 models under two scenarios of SSP2.4-5 and SSP5.8-5 were used. We divided the period into four twenty-year periods, which are the first period (2020-2040), the second period (2041-2061), the third period (2061-2080), and the fourth period (2081-2100), respectively. To evaluate the air temperature which is the output of selected CMIP6 models, three statistical measures of RMSE, NSE and KGE were used. Using the Delta Change Factor (DCF) method, the bias of the models was corrected. Then, non-parametric Man-Kendall (MK) and Sen’s Slope Estimator tests were used to analyze trend analysis and trend slope in long-term data series.     The maximum temperature is seen on the northern coast of the Persian Gulf and the Sea of Oman and the minimum temperature is seen in the northwest following the heights of the Zagros and also in the north of Iran (Alborz Mountains). The minimum annual temperature of 10.80°C was calculated based on observed data for the period 1990-2009, and the maximum temperature was 27.90°C on the coasts of the Oman Sea in southeastern Iran and Khuzestan province on the shores of the Persian Gulf in southwestern Iran. The intensity of the increase in temperature in Iran in mountainous areas is mainly due to the increase in the minimum temperature rather than to the maximum one.    Generally, the intensity of the warming in Iran is mostly projected in cold and temperate regions. There is also a tendency for the temperature to rise further at higher latitudes.    The projected temperature of CMIP6 models based on the SSP2.4-5 and SSP8.5-8 scenarios in Iran over four 20-year periods from 2020 to 2100 showed that the average slope of the temperature trend in Iran will reach 0.05°C per year, which shows an increase by a factor of 0.01 throughout Iran. As a general result, the annual trend of air temperature in Iran, based on observational data and projected output of CMIP6 models, shows warmer climate conditions for Iran. Temperature anomaly was not negative in any of the scenarios and periods; whereas positive anomaly is seen throughout the country. This increase in anomaly can be a major threat to the country's water resources.}, keywords = {Temperature,CMIP6 models,SSP scenarios,DCF,Iran}, title_fa = {بررسی بی‌هنجاری و روند دمای ایران در پهنه‌های مختلف اقلیمی با استفاده از مدل‌های جفت شده پروژه مقایسه متقابل مرحله ششم (CMIP6)}, abstract_fa = {دما یکی از عناصر شکل­گیری آب‌وهوا است و تغییرات آن می­تواند ساختار آب‌وهوای هر منطقه را تغییر دهد. برای بررسی چشم­انداز دمای آینده ایران از دو دسته داده شامل دمای 43 ایستگاه همدید و برونداد سه مدل BCC-CSM2-MR، CAMS-CSM1-0 و MRI-ESM2-0 از مجموعه مدل­های CMIP6 برای دو دوره تاریخی (2009-1990) و آینده (2100-2020) با تفکیک افقی ۱۰۰ کیلومتر استفاده شد. برونداد هر سه مدل برای دو سناریوی خوش­بینانه (SSP2-4.5) و بدبینانه (SSP5-8.5) بررسی شد. برای این منظور از سنجه­های آماری RMSE، NSE و KGE جهت درستی­سنجی مدل­ها استفاده شد. برای تصحیح اریبی برونداد مدل­ها از روش تغییر عامل دلتا (DCF) و برای مطالعه روند و شیب روند از آزمون­های من- کندال و سنس استفاده شد. نتایج بررسی مدل­ها در هفت پهنه اقلیمی ایران نشان داد که مدل BCC-CSM2-MR در دو پهنه BWh و Bsh عملکرد بهتری دارد و در پنج پهنه اقلیمی دیگر، مدل CAMS-CSM1-0 بهترین عملکرد را دارد. بی­هنجاری دما در دهه­های آتی در هر دو سناریو در ایران مثبت است و توزیع آن از توپوگرافی پیروی می­کند. همچنین روند دما در ایران افزایشی است. بیشینه روند افزایشی دما با نمره استاندارد 3.77 بر اساس سناریوی SSP5-8.5 به‌دست­آمده که در سطح 0.01 معنی­دار است. متوسط شیب روند دما در ایران طی دوره­های آتی به ازای هر سال به میزان 0.05 درجه سلسیوس افزایش خواهد داشت که رشد 0.01 را نسبت به دوره مشاهداتی نشان می­دهد.}, keywords_fa = {دما,مدل‌های CMIP6,سناریوهای SSP و DCF,ایران}, url = {https://www.ijgeophysics.ir/article_118940.html}, eprint = {https://www.ijgeophysics.ir/article_118940_6cdfc81d4bdd585b315311c1de0b00c6.pdf} }