Diatoms in Arctic regions: Potential tools to decipher environmental changes
Paleoclimate research define the baselines for the natural climate change and is imperative to help us to set the recent observed changes in the long-term natural climate context. Fossil marine diatoms have proved to be an excellent tools for the paleoclimatic reconstructions, e.g. for the reconstruction of sea surface temperature (SST) and sea ice. A number of studies have been conducted from the northern high latitude region using diatoms as potential proxy. Nevertheless, these studies are scattered and thus there is a need to expand diatom research in the Arctic regions. Due to the possibilities offered by an emerging trend of diatom-based research, it is important to identify both the research themes and geographical areas of highest importance in order to obtain the best possible scientific outcome in the research. Here we review some of up-to-date diatom-based reconstruction methods applicable for paleoceanographic research for the northern North Atlantic and Arctic regions, and discuss the knowledge gaps in the Arctic research, which potentially can be solved by diatom applications. The modern diatom research has progressively concentrated on quantitative reconstruction based on diatoms and statistical transfer function providing the most useful data for the climate research. However, also qualitative reconstruction methods are still needed; the recent studies show that although the quantitative reconstruction method for SST appears to be statistically robust, there are uncertainties in quantitative reconstructions for sea-ice, and thus it is still recommended to use the Marginal Ice Zone diatom taxa as a qualitative reconstruction method for the Arctic sea ice. Diatom applications offer highly potential tools for filling the knowledge gaps in the Arctic research.