Changes in Latvia's seacoast (1935-2007)

This paper presents the first compilation of available published scientific material from the 20^th century and results of research during the past 15 years in the seacoast process monitoring system. Using the first Latvian coastal land surveys from the 1930's and analysis data from topographic maps from the 1980's, changes in the Baltic coastline (growth and erosion) over a period of 50 to 60 years have been determined and maps of these changes have been made. The data indicates significant seacoast erosion that exceeds 50-60 m at the open Baltic seacoast, but reaches a maximum of 100-200 m, especially influenced by the large ports (Ventspils, Liepāja). Coastal erosion is significantly less along the coast of the Gulf of Riga. Coastal growth by the accumulation is seen along limited portions of the coast. During the last 15 years, coastal erosion due to severe storms has increased significantly by a factor of 1 to 3 times compared with the rate observed during the last 50-60 years of the 20^th century.