Diatom data from 'Missing sea-level rise in southeast Greenland during and since the Little Ice Age', published in Climate of the Past, 2023.

The datasets are raw diatom counts (minimum 250 count size) from a transect across a modern saltmarsh at the mouth of Dronning Marie Dal in south east Greenland (63.470N, -41.925W), and from a fossil core taken from the high marsh environment within the same marsh. The data was collected on 19/07/2014 during a research cruise to the area as part of the X_Centuries research project funded by the Danish Council for Independent Research 30 (FNU) (grant no. DFF-0602-02526B). Modern samples were taken from the top 1 cm of saltmarsh sediment using a knife, bagged and shipped to the laboratory where they were prepared for diatom analysis using standard methods (Palmer and Abbott 1986). The core was taken using a spade to dig a shallow pit from which a sediment section was extracted, wrapped in plastic and transported to the laboratory. Diatom samples were taken from the sediment core in the laboratory at 0.25 and 0.5 cm intervals using a scalpel. Counts were taken under a light microscope at 400x magnification. Only unbroken valves were counted. The taxonomy follows Van der Werff and Huls (1958-74), Hartley (1996) and Patrick and Reimer (1966, 1975). Modern samples and the core-top elevation were surveyed in the field using a Sokkisha level to mean tide level, established via a pressure transducer that logged tidal variations at 15-min intervals at Timmiarmiut, 100 km to the South, during fieldwork. These tidal levels were related to tidal predictions at Tasiilaq, 300 km to the NE. This data was collected to develop a modern training set of diatom distributions across saltmarshes in Greenland and to reconstruct recent (past few hundred years) of relative sea-level changes from saltmarsh sediments in this area of Greenland.

Hartley, B., 1996. An Atlas of British Diatoms. Biopress Limited, Bristol, UK, 601 pp.

Palmer, A.J.M., Abbott,W.H.,1986. In: Van De Plassche, O. (Ed.), Diatoms as indicators of sea-level change. Sea-level Research. Geo Books, Norwich, pp. 457–487.

Patrick, R., Reimer, C.W., 1966. The diatoms of the United States exclusive of Hawaii and Alaska. Monograph of the Academy of Natural Sciences of Philadelphia, 13, Vol. 1 601 pp.

Patrick, R., Reimer, C.W., 1975. The diatoms of the United States exclusive of Hawaii and Alaska, Part 1. Monograph of the Academy of Natural Sciences of Philadelphia, 13, Vol. 2 213 pp.

van der Werff, H., Huls, H., 1958-1974. Diatomeenflora van Nederland. Koeltz Scientific Books, Koenigstein.