Source: Geophysical Research Letters
Marine dust records provide the long-term perspective on dust flux from the continent of Asia to the Northwest Pacific Ocean. Tang et al.  present a new contribution from the Philippine Sea, providing a comparison to existing records from further north.
This comparison of two marine reconstructions reveals large scale similarities resulting from the aridification of Asia, but also differences that illuminate a northward shift in the westerly wind transport after 23 million years ago – linked to the uplift of Tibet – with the westerlies reaching their modern position about 9 million years ago.
The dust carries fingerprints of source regions that can be differentiated by neodymium and strontium isotopes. The 2.9-kilometer water depth of the study site means that carbonates are preserved, providing sufficient biostratigraphy to determine the dust fluxes – dust amount per unit time – from land to sea. This new record adds to what is known about the regional evolution of climate as global cooling and Tibetan uplift progressively altered the climate and landscapes of the Miocene.
Also of note is that this study retrieved new evidence out of Deep Sea Drilling Project cores collected in 1975, showing that the cores are still useful and contain many more such archives waiting to be explored.
Citation: Tang, Y., Wan, S., Clift, P. D., Zhao, D., Xu, Z., Zhang, J., et al. (2022). Northward shift of the Northern Hemisphere westerlies in the early to late Miocene and its links to Tibetan uplift. Geophysical Research Letters, 49, e2022GL099311. https://doi.org/10.1029/2022GL099311
—Sarah Feakins, Editor, Geophysical Research Letters