Detecting climate change in Ukraine: trends, prediction and extreme events
Authors: Bohushenko Anna , Stepanenko Sergiy , Khomenko Inna 
Published: March 2021

&lt;p&gt;In this study the trends and variations in 25 extreme temperature and precipitation indices&lt;br&gt;defined by ETCCDI, are examined using trend method, probability distribution analysis and&lt;br&gt;spatial statistics for periods of 71 to 137 years for 16 stations evenly distributed in Ukraine. Data&lt;br&gt;on the indices were obtained from www.ecad.eu.&lt;br&gt;Since 1981, temperature has increased by about 1&amp;#186;C in all stations in question relative to the&lt;br&gt;period of 1945-1980. Analysis of the temperature indices indicates that during the 20th and the&lt;br&gt;beginning of the 21th century there is significant warming which is particularly pronounced in&lt;br&gt;annual mean and annual maximum temperatures. Occurrence of more summer days, warm days&lt;br&gt;and tropical nights and warm spell duration reached the record highest level, and conversely&lt;br&gt;occurrence of frost and ice days, cold days and cold spell duration fall to a record low for the last&lt;br&gt;three decades in the most of study territory.&lt;br&gt;Since 1981, precipitation amount has grown by 30-50 mm relative to the period of 1945-1980 for&lt;br&gt;the most of Ukrainian territory, except Uzhhorod and Uman where precipitation amount has&lt;br&gt;remained the same. For Ukraine average, an increase in maximum daily and maximum 5 days&lt;br&gt;precipitation amount, the maximum number of consecutive wet days, heavy and very heavy&lt;br&gt;precipitation days, and a decrease in the maximum number of consecutive dry days are observed&lt;br&gt;for the last three decades.&lt;br&gt;The analysis of the spatial distribution of trend of precipitation and temperature indices showed&lt;br&gt;that there are large differences between regions of Ukraine, and coherence of spatial distribution&lt;br&gt;of trends of various indices is low.&lt;br&gt;Spectral analysis and harmonic regression techniques were used to derive simulated and&lt;br&gt;predicted (2019-2050) values of annual precipitation and annual mean temperature and four&lt;br&gt;indices such as maximum value of daily maximum temperature, minimum value of daily&lt;br&gt;minimum temperature, the highest 1-day precipitation amount and maximum number of&lt;br&gt;consecutive dry days for some stations such as Kerch (the Crimean Peninsula), Kyiv (situated in&lt;br&gt;north-central Ukraine along the Dnieper River), Lubny (Dnieper Lowland), Lviv and Shepetivka&lt;br&gt;(Podillia Upland), Uzhhorod (Transcarpathia), Uman (Dnieper Upland).&lt;br&gt;Annual mean temperature and maximum value of daily maximum temperature were predicted to&lt;br&gt;increase by 0.33&amp;#176;C per decade in the period of 2019-2050 with respect to 1981-2018, while&lt;br&gt;minimum value of daily minimum temperature was predicted to grow slightly faster (by 0.43-&lt;br&gt;0.63&amp;#186;C per decade).&lt;br&gt;Precipitation was predicted to increase for the stations in question by 20-66 mm up to 2050&lt;br&gt;relative to 1981-2018 and conversely maximum number of consecutive dry days will slightly&lt;br&gt;decline except Lubny where increase in an aridity index was predicted. In the next three decades&lt;br&gt;changes in maximum daily precipitation will be various: in Shepetivka and Kyiv such&lt;br&gt;precipitation will be decreased and in other stations increasement in such precipitation will be up&lt;br&gt;to 6 mm till 2050 with respect to 1981-2018.&lt;/p&gt;