Climate changes in the city of Chernivtsi during global warming

Abstract

Climate change trends in Chernivtsi, which began to be observed in the late 1990^s, have become clear unidirectional trends. The statistically confirmed time limit for the period of changes in the conditions of thermal regime formation is 1989.

Average annual air temperatures at the climatic norm of 7.9 °C in 1999 crossed the 8.5 °C threshold, and after 2013 they became higher than 10 °C. They increased most intensively during 2008–2023.

In the course of average annual air temperatures, a “step-like” pattern began to emerge, manifested as alternating periods of rapid increase with fluctuations relative to a new higher level.

Temperatures in all months have risen, most notably in winter (by 2.5 °C in January) and summer (by 2.4 °C in July and August). Over the past 20 years, winter temperatures have risen by 2.3 °C and summer temperatures by 2.7 °C.

The rise in air temperatures in Chernivtsi was accompanied by an increase in annual precipitation, a trend that began to be clearly observed after 1963. With the overall increase in annual precipitation, there was an intra-annual redistribution of precipitation, the features of which differed somewhat in 2000–2010 and 2011–2021. During both time periods, precipitation increased in winter and autumn months. In 2000–2010, precipitation in months IV–VI decreased, while in 2011–2021 it was quite noticeable – the amount of precipitation in months VII–IX decreased by 46 mm. With the decrease in precipitation accompanied by rising air temperatures, most of the summer and early fall in Chernivtsi became hot and dry.

As a consequence of the increase in air temperatures in the winter months, the duration of the winter season decreased, and the month of February became, in fact, the first spring month. The dates of the beginning of the destruction and complete melting of the snow cover were observed 10–14 days earlier. On average, the number of days with snow cover decreased by 12 days, and its height decreased by 13 cm.

Changes in the thermal and precipitation regimes have not yet led to an increase in the continental climate of Chernivtsi. The availability of a number of observations of sufficient (35 years) duration, covering the period of climate change with clear unidirectional trends in variations of meteorological elements, necessitates updating the climate norms.