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Late Cretaceous winter sea ice in Antarctica? was New Xinjiangchelys species and other non-dino Mesozoic papers

Reposted to make sure everyone sees it!

Vanessa C. Bowman, Jane E. Francis and James B. Riding (2013)
Late Cretaceous winter sea ice in Antarctica?
Geology (advance online publication)
doi: 10.1130/G34891.1

The Late Cretaceous is considered to have been a time of greenhouse
climates, although evidence from Maastrichtian sediments for rapid and
significant sea-level changes suggests that ice sheets were growing
and decaying on Antarctica at that time. There is no direct geological
evidence for glaciation, but we present palynomorph records from
Seymour Island, Antarctica, that may suggest Maastrichtian sea ice.
The dinoflagellate cyst Impletosphaeridium clavus is dominant. We
propose that its profusion may signify the accumulation of resting
cysts from dinoflagellate blooms related to winter sea ice decay.
Prior to the Cretaceous-Paleogene transition, I. clavus decreased
dramatically in abundance; we link this with climate warming.
Terrestrial conditions inferred from pollen and spore data are
consistent with our climate interpretations based on I. clavus
together with delta18O values from macrofossils. These data and our
interpretation support the presence of ephemeral ice sheets on
Antarctica during the latest Cretaceous, highlighting the extreme
sensitivity of this region to global climate change.