Investigating the trend of changes in the heat wave properties Related to climate change in arid regions (Case Study: Yazd City)

Today, global warming and climate change are considered to be the greatest challenge of human life that has overshadowed other environmental challenges. In this study, it has been attempted to detect climate change phenomena in Yazd by monitoring the trend of heat wave changes and its relation to temperature anomaly. For this purpose, daily temperature data for the time period (1960– 2017) were used. Finally, the characteristics of heat waves such as the number of occurrences of heat waves, frequency of days with heat waves, heat wave continuity, magnitude and intensity of heat waves and average heat wave (hottest day of heat wave) using ClimPACT software in programming environment R 2.10 were calculated. Heat waves are the result of incremental temperature changes. Therefore, temperature anomaly of Yazd station was extracted and compared with the temperature anomaly of the Land's surface. The relationship between heat wave indices and temperature anomalies was investigated. The results showed that the highest number of heat wave events occurred in 2010 and 2016. The number of days associated with the hot wave has increased significantly, with 47 and 42 days in 2010 and 2016, respectively. An increasing trend in the continuity and intensity of heat waves was also observed. The longest continuation for 2013 was estimated to be 13 days. The findings also show that in the last two decades the magnitude of the heat wave has reached more than 31 ° C. Investigation of the relationship between all indices related to heat wave and Yazd temperature anomaly showed good correlation and coefficient of explanation of temperature anomaly and frequency of days with heat wave was higher than other indices and its R2 was approximately 0.6108. In general, the results indicate the intensification, continuity and intensity of heat waves in Yazd city, which can indicate the occurrence of climate change, especially in the last two decades in this region of the country as a representative of the arid regions. Due to the increasing temperature in the coming years on the frequency, intensity and continuity of these waves will increase, knowing how heat waves are processed can help managers and planners make risk management decisions about energy efficiency.