Varved lake sediments provide climatic records with seasonal to annual
resolution and low associated age uncertainty. Robust and detailed
comparison of well-dated and annually laminated sediment records is
crucial for reconstructing abrupt and regionally time-transgressive
changes as well as validation of spatial and temporal trajectories of
past climatic changes. The VARved sediments DAtabase (VARDA) presented
here is the first data compilation for varve chronologies and
associated palaeoclimatic proxy records. The current version 1.0
allows detailed comparison of published varve records from 95
lakes. VARDA is freely accessible and was created to assess outputs
from climate models with high-resolution terrestrial palaeoclimatic
proxies. VARDA additionally provides a technical environment that
enables us to explore the database of varved lake sediments using a
connected data model and can generate a state-of-the-art graphic
representation of a multisite comparison. This allows the reassessment
of existing chronologies and tephra events to synchronize and compare
even distant varved lake records. Furthermore, the present version of
VARDA permits the exploration of varve thickness data. In this paper, we
report in detail on the data-mining and compilation strategies for the
identification of varved lakes and assimilation of high-resolution
chronologies, as well as the technical infrastructure of the
database. Additional palaeoclimatic proxy data will be provided in
forthcoming updates. The VARDA graph database and user interface can
be accessed online at https://varve.gfz-potsdam.de (last access: 15 September 2020), all datasets
of version 1.0 are available at https://doi.org/10.5880/GFZ.4.3.2019.003
(Ramisch et al., 2019)....

VARDA (VARved sediments DAtabase) – providing and connecting proxy data from annually laminated lake sediments

10.5194/essd-12-2311-2020