Paleoclimate data provide unique insights into climate dynamics across a range of timescales. Importantly, paleoclimate data are the only means of evaluating and constraining climate models under boundary conditions different from today and the recent past. However, most paleoclimate data are presently archived in a fragmented and non-standardized way, necessitating synthesis efforts in order to allow meaningful analysis of spatio-temporal climate dynamics and data-model comparison. Moreover, paleoclimate data are inherently uncertain since they are based on indirect evidence (proxies) and associated with chronological error, requiring rigorous uncertainty analysis to separate signal from noise and to make full use of paleoclimate data syntheses.

This special issue provides a platform to present paleoclimate synthesis products, to review the current state of proxy uncertainty analysis, as well as to present new developments. The issue is organized within the paleoclimate data synthesis working group of the PALMOD (http://www.palmod.de/ ) project, which focuses on the past 130,000 years. However, this is an open submission issue and we explicitly invite contributions from across the paleoclimate community describing synthesis methods and results from any kind of archive and/or parameter. We welcome contributions presenting paleoclimate synthesis products and their analysis across timescales, with regional or global focus and both time slice and transient approaches as well as conceptual contributions to proxy data uncertainty analysis (theoretical, empirical, Bayesian).