Investigating the trend of night temperature changes in Iran and the effect of carbon dioxide

In this article, night temperature changes in relationship with CO2 emissions in Iran were studied using AIRS satellite images and time series graphs, regression, correlation and Mann-Kendall tests and maps. This research was conducted for the statistical period of 2003-2016 and the months of January, May, July, and November. The statistical analysis of the distribution of the average night temperature in Iran showed that the average of 2016 was higher than the average of the entire study period by 0.42 degrees Kelvin. The highest fluctuations in night temperature were related to the winter season and the months of November and January, and the lowest fluctuations were related to the summer season and the month of July. The trend of the seasonal average of CO2 in all four seasons was completely increasing and had little fluctuation. Based on the distribution of the average seasonal night temperature, the minimum night temperature were visible in the northwest, Alborz, and Zagros mountain ranges and North Khorasan in all f seasons. The southern coasts and southern coastal regions, including Khuzestan province, Bushehr province, Hormozgan and Sistan and Baluchistan provinces, as well as Kavir desert and Lut desert, have the maximum night temperature in all seasons. According to the results of the Mann-Kendall test, only the trend of night temperature in July was significant, and the trend of Co2 was upward and significant in all months. According to the results of Pearson's correlation test, night temperature in July has a high correlation (0.66) with CO2. The results of the non-linear regression model between the two variables indicated that with a coefficient of determination of 0.44, the maximum CO2 had the greatest impact on the maximum night temperature in July in the study period of 2003-2016.