Heat waves: critical rewiew of the literature; estimation for Khabarovsk

The author presents a critical review of literature on heat wave definitions that highlights the main methods for estimation of episodes with extremely high temperatures. Two of them were applied to reveal heat waves in summer in Khabarovsk during the period of 1952-2012. From one to three summer heat waves were registered for the initial three decades, and 4-13 - in the second half of the period, with their maximum occurrence in the last decade. A slight positive trend is stated for the dynamics of maximum temperatures, while variations between different years may be as high as ±4° С. The climate variability has been significantly changing for the last 60 years, but generally it does not cross the limits of two standard deviations.