Causes and course of climate change and its hydrological consequences in the Greater Poland region in 1951-2020

Abstract

The paper presents effects of changes in climatic elements in the Greater Poland region (Poland), their causes and consequences for shaping the water balance of this area, copying with the most severe water deficit in Poland. The study period covers 70 years (1951–2020). The research identified an abrupt and significant change in the climate of Greater Poland, which started between 1987 and 1989, concerning not only air temperature but also a wider spectrum of climatic elements. The change in the state of the climate, which covers the entire Atlantic-Eurasian circulation sector, re-sults from a sudden change in the macro-circulation conditions in the middle troposphere (500 hPa). The reason for the change in the mid-tropospheric circulation is an equally abrupt and simultaneous change in the intensity of the ocean heat transport by the North Atlantic thermohaline circulation (NA THC). Climate change observed in Greater Poland is manifested in an increase in sunshine duration (SD) and air temperature, a decrease in relative humidity, a change in the cloud structure, and an increase in the degree of sky coverage. The main, physical reason for an increase in air tempera-ture is a rapid and strong increase in SD in the warm half-years, which began after 1988, and a significant increase in the frequency of positive North Atlantic Oscillation (NAO) phases in winters. The ongoing climate change entails various effects, among which the most important is considered to be hydrological consequences. The water balance of Greater Poland is becoming increasingly unfavourable, mainly as a result of a rapid increase in field evaporation.

Development and Validation of the Curiosity of Climate Changes Scale

“…2 The effects of climate change can be seen in the increasing frequency of heat waves, droughts, floods, heavy rainfall and hurricanes and a significant portion of those consequences are interrelated, causing each other to amplify. [3][4][5] These highly adverse weather events cause a range of damage and destruction in various sectors such as agriculture, fisheries, forestry and tourism. [6][7][8][9] They also have a negative impact on human health, both physical and mental.…”

Evaluation of Different Geographic Provenances of Silver Fir (Abies alba) as Seed Sources, Based on Seed Traits and Germination

“…Current predictions of future climate change have a high degree of uncertainty, and their potential effects on forests are causing increasing concerns. Climate change, directly or indirectly, affects tree growth and forest productivity [4][5][6]. Changes in temperature and precipitation, as well as the increase in carbon dioxide levels, also have effects on the vegetative state of trees and their biological processes, influencing even the most complex forest ecosystems in various ways.…”

“…Changes in temperature and precipitation, as well as the increase in carbon dioxide levels, also have effects on the vegetative state of trees and their biological processes, influencing even the most complex forest ecosystems in various ways. Furthermore, the loss of biodiversity constitutes one of the major problems recently caused by climate change [4,7,8]. Thus, due to the expected unfavorable environment shift, the natural growing areas for most species will be affected, and trees, like other plants, react in different ways to these changes [9].…”

Changes of Hydrological Extremes in the Center of Eastern Europe and Their Plausible Causes

“…Climate change in eastern Europe was detected in the early 1970s. This has strengthened since the 1990s [25][26][27][28]. Since 1990, the air temperature in Belarus has increased by 1.3 • C above the climatic norm of the 1961-1990 period [29].…”

“…Throughout Poland, summer runoff reduced by a maximum of 15-20%, and in autumn by 10-15% in 1988-2020 [64]. The water balance of Greater Poland (i.e., the central western part of the country) is becoming negative, mainly because of a rapid increase in agricultural evaporation [28]. As a result, in 1989-2020, there was a significant increase in the number of days with a low flow (Q below the tenth percentile) detected in about two-thirds of Poland's overall area.…”