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The modern-day northwest Australian summer monsoon is dynamically coupled to other
regional monsoon systems and inflows from the Indian Ocean, however, the nature of these
relationships over longer time scales is uncertain. Previous attempts to evaluate how proxy records
from the Indonesian-Australian monsoon region correspond to other records from the Indian and East
Asian monsoon regions, as well as to El Ni\~no-related proxy records, has been qualitiative, relying on
`curve-fitting' methods. Here, we seek a quantitative approach for identifying coupling relationships
between paleoclimate proxy records, employing statistical techniques to compute the interdependence
of two paleoclimate time series. We verify the use of complex networks to identify coupling
relationships between modern climate indices which correspond to physically-based mechanisms. This
method is then extended to a set of paleoclimate proxy records from the Asian, Australasian and South
American regions spanning the past 9,000 years. The resulting networks demonstrate the existence of
coupling relationships between regional monsoon systems on millennial time scales, but also highlight
the transient nature of teleconnections during this period. In the context of the northwest Australian
summer monsoon, we recognise a shift in coupling relationships from strong interhemispheric links
with East Asian monsoon proxy records, as well as those possibly related to ITCZ positioning, in the
mid-Holocene to significantly weaker coupling in the later Holocene. Although the identified links
cannot explain the underlying physical processes leading to coupling between regional monsoon
systems, this method provides a step towards understanding the role that changes in teleconnections
play in millennial- to orbital-scale climate variability.
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