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This paper presents new bio-, litho- and chronostratigraphical evidence from two adjacent sediment sequences of the Tõdva and Saku basins, northern Estonia that refine the age estimate of the Palivere ice-marginal zone and the deglaciation history of Estonia. Previous palynological studies demonstrated the presence of late-glacial sediments in the area; however, those sections were not dated, and their ages were poorly constrained. New accelerator mass spectrometry (AMS) 14C dates show that sedimentation in the Tõdva basin started at approximately 13 200 cal yr BP. Therefore, because the studied sites are located at the distal part of this zone, we infer that this age represents the minimum timing of the ice retreat from the Palivere ice-marginal zone.

The island of Suursaari in the middle of the Gulf of Finland is exceptionally high (175 m a.s.l.). Sediment profiles from one mire and three lakes were investigated using diatom and pollen analysis, radiocarbon dating and levelling of the elevations of ancient shorelines. The pollen stratigraphy of the Lounatkorkiasuo Mire sediment suggests a sedimentary record dating from the late Allerød. The development of late-glacial vegetation went through the same phases as in southern Finland, however these are probably somewhat earlier on the island of Suursaari. There are differences in the Holocene vegetation history of the higher and lower areas of the island. Lake Ruokalahenjärvi was isolated around 10 000 BP during the initial phase of the Yoldia Sea and the diatom assemblage indicates that at that time brackish-water flow had not penetrated into the Gulf of Finland. Diatoms from the isolation sediments of Lake Liivalahenjärvi and Lake Veteljärvi indicate a freshwater environment for the Yoldia Sea final phase at 9500–9600 BP. Levelling of coastal formations on Suursaari Island reveals that the Late Weichselian and early Holocene ancient shorelines are 5–15 m higher than expected from the isobase data for similar land uplift areas on the mainland. The anomalous shoreline levels on Suursaari Island may be explained by irregular land uplift. By the time of the Litorina Sea differences in shoreline altitudes had disappeared.

Two main types of permafrost are found in northern Finland. The most widely known occurence is in mires, in peat mounds with permanently frozen cores known as palsas. Some fully new, small occurrences have been found in pounus, small peat humps over large areas in Lapland. The second main type of permafrost occurrence is located above the tree line on barren fell summits there permafrost means continuous temperature below 0°C in the bedrock .Some massive cave ice has been found in Lapland, too. The climatic conditions at permafrost sites are still poorly know because the local topography affects the temperature conditions. Only sporadic recordings are available from the summits of fells and from palsa mires. In general, the mean annual air temperature for permafrost formation should be below -1°C. Snow depth seems to be the most critical factor for permafrost formation in Lapland: thin snow cover promotes frost penetration. Vegetation provides a useful indicator of snow depth and of possible permafrost sites. Some proposals are made for permafrost studies in Lapland.