Boreālais reģions

In Jelgava, the main challenges from rainfall include high risk of flooding and damage to infrastructure during prolonged rainfall. The Lielupe River and its tributary floodplains, as well as low topography and high-water tables, make drainage and stormwater drainage systems difficult to operate. The extreme rainfall of July 2024 confirms that the existing sewerage system is inadequate to cope with such situations.  In the region’s rural areas, the threats affect both settlements and villages and fertile agricultural land, which plays an important role in the region’s economy.

Storms are the second most pronounced weather extreme in the region and, although on average winds are not expected to change significantly over the 21st century, by the end of the century (relative to the period 1971-2000) there will be a greater number of both windless days and stormy days per year.  In recent years, the Zemgale region has been severely affected by thunderstorms and storms that have brought heavy rainfall in the form of both rain and hail, destroying agricultural crops and damaging infrastructure in many places. Severe storms in summer and early autumn, when trees and shrubs are still in leaves, have caused severe damage.

Climatologists believe that the current extreme values will become the norm in the future, while extreme weather events will cause even more damage. Climate models also predict an increase in total annual precipitation over the 21st century, with an average annual precipitation in Latvia of 775.7 [±60.0] mm for minor, 806.5 [±72.8] mm for moderate and 814.2 [±79.7] mm for major climate change. Predictions foresee substantial increase in duration of heatwaves from climatic norm of 8 days to 16 [±8] days for minor, 22 [±9] days for moderate and 33 [±12] days for major climate change.

Forecasting extreme weather events is quite complicated task, as these events are characterized by short-term nature, they and spatially limited, and thus short warning times are operational. Measures for adaptation to climate change thus become essential by preparedness for more days with extreme temperatures and for more extreme precipitation events. Decision-makers and local authorities need data and information to make the necessary preparations in advance by adapting to the different scenarios and possible consequences.

Within activities of IMPETUS project, the Adaptation Pathways are elaborated for Zemgale region with particular focus on flooding occurrences from river spring floods and heavy rain events:

• Adaptation pathways are developed to support in better management of river flood risks and heavy rain floods (flash floods).
• Aimed to implement a set of measures for reducing the frequency and extent of flooded areas in both rural (agricultural) land and urban settlements.
• In exchange with the stakeholders, adaptation options are identified, assessed and included in the pathways to increase adaptive capacity in Zemgale region.
• Structural measures, e.g., upgrading of existing drainage and stormwater drainage systems, and aligning them with nature-based solutions for water retention in rural and urban areas, and cleaning of riverbeds are considered.
• Non-structural measures for improving flood risk early warning system (EWS), increasing awareness of inhabitants and improving the efficiency of actions of competent authorities in case of floor risks are addressed.