Global precipitation change during the Holocene: a combination of records and simulations

Precipitation can shape our climate both in the present and the future. Even though we have made significant advances in studying the mechanisms of millennial-scale climate changes through high-resolution records, we still cannot quantitatively characterize the global spatiotemporal precipitation variations within the Holocene. Therefore, we developed a new approach to integrating data from 349 globally distributed records and climate models to reconstruct regional and global precipitation patterns over the last 12000 years. Our results reveal that precipitation reconstructions can be divided into monsoon-driven and westerly driven patterns. The results suggest that an arid climate was experienced in the late glacial and early Holocene epoch (& SIM;12-7.4 cal ka BP), attaining a middle Holocene optimum (& SIM;7.4-3.5 cal ka BP), and drier after the middle Holocene. According to our reconstructions, the global precipitation reconstruction increased from the early Holocene until 3.8 cal ka BP and then subsequently decreased. In addition, our reconstructions better reproduce the low-frequency events and extreme precipitation at the millennial scale in the hemispheres, but the performance of the reconstructions in the equatorial Pacific and the Southern Hemisphere of Africa and the Americas is controversial. The resolution of the record and the simulation capability of the climate model remain important means to improve our understanding of past climate change.

Automated summary

Precipitation is important for current and future climate. Using data from 349 records and climate models, we reconstructed regional and global precipitation patterns over the past 12000 years. Our results show that precipitation patterns can be divided into monsoon-driven and westerly driven categories. The reconstructions indicate periods of arid and wet climate, with increasing global precipitation until the early Holocene and subsequent decrease. The performance of the reconstructions in the equatorial Pacific and the Southern Hemisphere of Africa and the Americas is controversial.