Response of the high-resolution Chinese loess grain size record to the 50°N integrated winter insolation during the last 500,000 years

摘要

The global ice volume change regulates the Earth's climate and has been characterized by 100,000 year cycles over the last 700,000 years. The Asian inland winter climate change is proposed to show primary 100,000 year cycles that mimic ice volume changes. Here we calibrate the age of a high-resolution grain size record over the last 500,000 years with a grain size age model. The results show a primary 41,000 year cycle and a weaker 100,000 year cycle during the last ~ 500,000 years. We suggest that the primary 41,000 year cycle in the grain size record can be ascribed to the 50°N integrated winter insolation. Our findings suggest that ice volume changes have a limited effect on the Asian inland winter climate. Asian continental winter climate changes respond to the 50°N integrated winter insolation in addition to ice volume changes.