Gordienko T., Tsvetayeva O.

Oles Honchar Dnipropetrovsk National University


Water is the softest, weakest creature in the world, but to overcome hard and strong it is invincible, and the world is not equal to it. (Tao Te Ching)

Water resources are used in various ways including direct consumption, agricultural irrigation, fisheries, hydropower, industrial production, recreation, navigation, environmental protection, the disposal and treatment of sewage, and industrial effluents. Water has sources and supplies, economic, social, and political characteristics which make it a unique and challenging natural resource to manage. The main climate change consequences related to water resources are increases in temperature, shifts in precipitation patterns and snow cover, and a likely increase in the frequency of flooding and droughts. Depending on the region, climate changes have widely differing effects on Europe’s water. Higher temperatures will generally intensify the global hydrological cycle. Annual precipitation trends in Europe indicate that the Northern Europe has become 10%-40 % wetter over the last century, whereas the Southern Europe has become up to 20 % drier. Over the last century annual river discharge has increased in some regions, such as Eastern Europe, while it has fallen in others, such as southern Europe.

Climate change may also change the seasonal variation in river-flow. Higher temperatures will push the snow limit upwards in northern Europe and in mountainous regions. This, in conjunction with less precipitation falling as snow, will result in a higher winter run-off in northern European and mountain-fed rivers, such as the Rhine, the Rhône, the Po, and the Danube. Moreover, earlier spring melts will lead to shift in peak flow levels. Climate change tends to increase the frequency and intensity of rainfall; there may be an increase in the occurrence of flooding due to heavy rainfall events. Groundwater recharge may also be affected with a reduction in the availability of groundwater for drinking water in some regions. Changes in average water availability in most European river basins are estimated to be relatively small for the next 30 years. However, in the long-term period most of the climate change scenarios predict that northern and Eastern Europe will have an increase in annual average river flow and water availability. In contrast, the average run-off in southern European rivers is projected to decrease.

The European area around the Mediterranean Sea is recognized as one of the world’s regions where climate change has the greatest adverse impact on water resources. This is the result of the combined effect of increasing temperatures and precipitation decrease. This combined effect will give the higher evapotranspiration rates and result in periods with low river discharges (hydrological droughts). Occurred drought periods were reported in many studies in the area. The average annual runoff will decrease by 2070 with 50 % in southern and southeastern Europe, and increase by up to 50 % or more in most parts of northern and northeastern Europe. It is possible that in the future the extreme precipitation will be more frequent, especially in winter and more intense but the uncertainty in the projections is high. In general, in Europe, the timing of the flood risk tends to shift from snowmelt in spring to summer, autumn or even wintertime. In the most of European countries the maximum monthly discharges occur from January to June and from south-west to the north-east. This reflects, besides the general climatic pattern with winter rains in the maritime areas (Iberian Peninsula, western France, Great Britain, and Mediterranean countries), the rising influence of snowmelt in the continental and northern areas with snow accumulation in winter and melting periods from March until June. In the 2070s, the maximum average discharge occurs about one month earlier than today in northern and parts of central Europe. This can be explained by a general rise in temperature in the climate model for these areas, which induces an earlier snowmelt.

So, water resource users can reduce the negative effects of water shortages through a number of strategies. These include revising water storage and release programs for reservoirs, adopting crops and cropping practices that are robust over a wider spectrum of water availability, adjusting water prices to encourage conservation and the expansion of water supply infrastructure. The ability to anticipate and efficiently prepare for future water resource management challenges is currently limited, in part, by imprecise regional climate change models and long-term weather forecasts. The uncertainty about future climate conditions makes it more difficult to optimally prepare for and adapt to associated changes in water resource availability and quality.