New Data on the Late Cretaceous Flora of the New Siberia Island, New Siberian Islands

Shallow-water temperature seasonality in the middle Cretaceous mid-latitude northwestern Pacific

“…Cold currents flowed from the Arctic to the western Tethys Ocean, including the depositional area of the Gosau Group (Walliser and Schöne, 2020). In contrast, during the Turonian, the Pacific Ocean was separated from the Arctic Ocean by the Bering Land Bridge Spicer, 1996, 2010;Herman et al, 2019). In this ocean-land configuration, the cold Arctic water could not flow into the Pacific Ocean, leading to warm shallow-water temperatures in the mid-latitude Pacific Ocean.…”

“…Low-temperature seasonality in the Northern Hemisphere during the Turonian is consistent with paleontological evidence from high-latitude plant and vertebrate fossils. Herman et al (2019) reported conifer-and angiosperm-dominant floras from the Derevyannye Gory Formation (Turonian-Coniacian) of the New Siberia Island, Russia (70°N paleolatitude) and they concluded that low-temperature seasonality was present in the Turonian-Coniacian Arctic. Vandermark et al (2007) reported that the extinct diapsid reptile Champsosaurus fossils from the Turonian-Coniacian sediments in Axel Heiberg Island, northern Canada (79°N, paleolatitude), was dominated by subadultstage individuals, suggesting that temperatures suitable for Comparison of monthly averaged shallow-ocean temperature and its seasonality in the western to northwestern Pacific regions among the middle Turonian, middle Cretaceous derived from this study (PU-1, PU-5, Averaged), and recent ocean derived from Japan Meteorological Agency (2024a) (Hokkaido) and Japan Meteorological Agency (2024b) (Okinawa).…”