title: Evolutionary History of Atmospheric CO2 during the Late Cenozoic from Fossilized Metasequoia Needles.
abstract: The change in ancient atmospheric CO2 concentrations provides important clues for understanding the relationship between the atmospheric CO2 concentration and global temperature. However, the lack of CO2 evolution curves estimated from a single terrestrial proxy prevents the understanding of climatic and environmental impacts due to variations in data. Thus, based on the stomatal index of fossilized Metasequoia needles, we reconstructed a history of atmospheric CO2 concentrations from middle Miocene to late Early Pleistocene when the climate changed dramatically. According to this research, atmospheric CO2 concentration was stabile around 330-350 ppmv in the middle and late Miocene, then it decreased to 278-284 ppmv during the Late Pliocene and to 277-279 ppmv during the Early Pleistocene, which was almost the same range as in preindustrial time. According to former research, this is a time when global temperature decreased sharply. Our results also indicated that from middle Miocene to Pleistocene, global CO2 level decreased by more than 50 ppmv, which may suggest that CO2 decrease and temperature decrease are coupled.
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Graduate School of Horticulture, Chiba University, 648 Matsudo, Chiba 271-8510, Japan.
authors.forename: Arata
authors.initials: A
authors.lastname: Momohara
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China; Central Laboratory, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Julie
authors.initials: J
authors.lastname: Lebreton-Anberrée
authors.affiliation: Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China; Key Laboratory of Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, CAS, Kunming 650204, China.
authors.forename: Zhekun
authors.initials: Z
authors.lastname: Zhou
mesh_terms: D001272:Atmosphere; D002245:Carbon Dioxide / Q000737:chemistry*; D002681:China; D002980:Climate; D029779:Cupressaceae / Q000502:physiology*; D005580:Fossils; D005843:Geography; D007564:Japan; D054046:Plant Stomata / Q000502:physiology; D010944:Plants; D029963:Quercus / Q000502:physiology*; D013696:Temperature
chemical_list: D002245:Carbon Dioxide