Drought

Prolonged periods with little or no precipitation can cause water scarcity and hamper vegetation growth. In southern Sweden the water demand is often greatest when resources are at their lowest. Access to water will likely change in the future, and climate scenarios show reduced water availability in large parts of southern Sweden.

Sweden, in an international context, is spared from major disasters caused by extreme drought. During dry years, however, water shortages pose serious challenges in the country both locally and regionally. It is mainly the eastern parts of southern and central Sweden that are affected.

Prolonged periods with little or no rainfall can inhibit the vegetation and directly affect crop production and forest growth. The consequences are even worse in combination with high temperatures as evaporation will increase. Drought causes low water flow to waterways and low water levels in lakes, leading to water shortages and competition between different types of water use such as water supply, irrigation or sewage. Many wildfires also occur as a result of prolonged drought.

The years of 1975, 1976 and 1983, are known as dry summers in Sweden. The early summer drought in 1992 has perhaps been the most difficult case in our country over the past 100 years. During the period 13 May to 11 July parts of southern Sweden received no or insignificant rainfall.

Water availability in the future

Water availability may change in the future. Climate scenarios indicate a decrease in large parts of southern Sweden. The reduced water supply is mainly due to the plants´ increased consumption in a warmer climate with longer growing seasons.  Higher temperatures also increase evaporation from soil and waterways.

Research at SMHI reports projections of future water supply, the number of days per year when it is relatively dry in the ground and the number of days per year when there is low water flow in the rivers. As for drought the greatest changes are expected in southern Sweden and in areas around the lakes of Vänern and Vättern, with over 60 more days of drought every year by the end of the century.