Changes in complex bioclimatic indicators in Crimea since the middle of the 20th century

BACKGROUND: Observed global climate changes can significantly influence on the regional climate anomalies and recreational conditions over the Crimean peninsula. AIM: To study the features of complex bioclimatic indicators changes on the territory of Crimea over a multidecadal period (~70 years), paying special attention to each month of the year, and on bases of obtained results to show the possible way of recreational activities development associated with these changes. METHODS: For calculations, we used daily hydrometeorological data for each month from the archive of observations at the network of European weather stations E-OBS (v. 17.0) from 22 stations and NCEP/NCAR R1 reanalysis for the period of 19502018. The obtained arrays were verified in accordance with an open database of standard daily station observations in Crimea in 20052018. To assess the impact of climate change on the human body, the equivalent effective temperature, normal equivalent effective temperature, weight content of oxygen in the air (partial oxygen density) (O2), wet wind chill index Hill (Hw) and index Bodmann dry wind chiller (S) were calculated. The features of their linear trends for each month in the Crimean Peninsula were analysed. RESULTS: Monthwise analyses of the bioclimatic indicator trends demonstrated an increase or decrease in recreational comfort in certain seasons. The most pronounced positive normal equivalent effective temperature trends over Crimea were observed from winter to spring. This indicated improved complex recreational conditions in recent decades and the possibility to extend the duration of the holiday season. The pO2, Hw and S indices had opposite tendencies throughout the year (except for December). According to the pO2 index, in the period from August to October, a physiological oxygen deficiency may be experienced throughout Crimea. Windy and uncomfortable bioclimatic conditions tend to increase in the steppes of Crimea in December. CONCLUSION: The patterns of changes in bioclimatic indicators revealed through this study can be used as a regulatory factor for effectively organising and conducting recreational activities in the territory of Crimea and thus ensure the duration of the recreational period.