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Abstract—The analysis of paleomagnetic data from Late Neoproterozoic complexes of Siberia and Australia is carried out. We show that the existing paleomagnetic datasets are in a disagreement with the concept of the axial-dipole configuration of the Late Neoproterozoic geomagnetic field: proposed non-actualistic models of the field do not reasonably explain the distribution of the paleomagnetic poles. We carried out analysis of paleomagnetic and virtual geomagnetic poles distribution based on simple geometric calculations. The analysis suggests that the configuration of the Late Neoproterozoic geomagnetic field was determined by the coexistence of a weak, long-lived source that was stably fixed in space, with a main dipole source that experienced sporadic multidirectional jumps within a certain preferred region of the Earth. Predominantly equatorial orientation of the main dipole source is substantiated by paleoclimate proxies. We propose a descriptive non-actualistic model of the Late Neoproterozoic geomagnetic field—the Devious Equatorial Dipole hypothesis, which brings paleomagnetic and paleoclimate data into accordance. [ABSTRACT FROM AUTHOR]

Change of global monsoon (GM) during the Last Glacial Maximum (LGM) is investigated using results from the multi-model ensemble of seven coupled climate models participated in the Coupled Model Intercomparison Project Phase 5. The GM changes during LGM are identified by comparison of the results from the pre-industrial control run and the LGM run. The results show (1) the annual mean GM precipitation and GM domain are reduced by about 10 and 5 %, respectively; (2) the monsoon intensity (demonstrated by the local summer-minus-winter precipitation) is also weakened over most monsoon regions except Australian monsoon; (3) the monsoon precipitation is reduced more during the local summer than winter; (4) distinct from all other regional monsoons, the Australian monsoon is strengthened and the monsoon area is enlarged. Four major factors contribute to these changes. The lower greenhouse gas concentration and the presence of the ice sheets decrease air temperature and water vapor content, resulting in a general weakening of the GM precipitation and reduction of GM domain. The reduced hemispheric difference in seasonal variation of insolation may contribute to the weakened GM intensity. The changed land-ocean configuration in the vicinity of the Maritime Continent, along with the presence of the ice sheets and lower greenhouse gas concentration, result in strengthened land-ocean and North-South hemispheric thermal contrasts, leading to the unique strengthened Australian monsoon. Although some of the results are consistent with the proxy data, uncertainties remain in different models. More comparison is needed between proxy data and model experiments to better understand the changes of the GM during the LGM. [ABSTRACT FROM AUTHOR]