"The combined sea ice data suggest that the seasonal Arctic sea ice cover was strongly reduced during most of the early Holocene and there appear to have been periods of ice free summers in the central Arctic Ocean."

"We therefore conclude that for a priod in the Early Holocene, probably for a millenium or more, the Arctic Ocean was free of sea ice at least for shorter periods in the summer."

"Calcareous nannofossils from approximately the past 7000 yr of the Holocene and from oxygen isotope stage 5 are present at 39 analyzed sites in the central Arctic Ocean. This indicates partly ice-free conditions during at least some summers"