Meteorite-impact astronomical events and global climatic changes during the Cenezoic

There were at least eight meteorite-impact astronomical events confirmed during the Cenezoic. However there were still three or more meteorite-impact astronomical events, e. g., 55 Ma Palaeocene-Eocene thermal maximum, 45 Ma Japanese Sea, and 41 Ma Drake Passage meteortite-impact events inferred from the direct evidences of meteorite impact or plate tectonic evolution during this period. All these meteorite-impact astronomical events may be related to the corresponding global climatic changes during the Cenezoic. The triggering factors for the global climatic changes during the Cenozoic include the meteorite-impact astronomical events, variations in the Earth's orbital parameters, decrease of CO₂ concentrations and variations in global carbon cycling, release of plentiful methane hydrates in the oceanic and atmospheric systems, variations in oceanic currents and global-scale tectonic movements (e. g., tectonic uplift, super mantle plume, and wide-spread volcanic activities), of which the meteorite-impact astronomical events are interpreted as the key triggering factors for the global climatic changes during the Cenezoic.