Characteristics and Formation of a Solitary Dune Belt Encountered along the Coast of Estonia

Abstract

Tõnisson, H., Suursaar, Ü., Rivis, R., Tamura, T., Aarna, T., Vilumaa, K., and Kont, A., 2020. Characteristics and formation of a solitary dune belt encountered along the coast of Estonia. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 689-694. Coconut Creek (Florida), ISSN 0749-0208.Dunes are not particularly high and widespread on practically tideless, prograding coasts of Estonia. The aim of the study was to document characteristics of a single-ridge, up to 10–14 m high, non-continuous dune belt (DB), existing 0.1–1 km landward from the contemporary shoreline. Using LiDAR-based elevation data, landscape profilings, and paleoclimatic proxies, its age and formation mechanism were studied. The results suggest that the DB is different and independent from adjacent aeolian landforms (foredune systems and paleodunes), and it follows the coastline regardless of its exposition at a similar height in more than 30 sparsely located coastal segments. In many cases it is partially reblown to 5–7 m elevation and sometimes it overrides the older well-organized foredune ridges. Based on site-specific land uplift rates and OSL dates, the formation of the dune began at around AD 1300. It gradually grew over most of the Little Ice Age (LIA), when cold conditions inhibited vegetation growth and allowed to release a considerable amount of movable sediment. Major reblow events probably occurred during the cold phases of the LIA from AD 1450 to 1750.