The Earth's climate underwent a striking change ca.2.73 Ma (million years) ago,characterizing by the onset and intensification of the major Northern Hemisphere glaciations(iNHG).A few factors have been considered in the driving the iNHG,one of which is the marine biological pump as a result of the increase of eolian dust in the ocean,transferring atmospheric CO_2 into the deep ocean during the onset of iNHG.The central Asian interior is the second largest center of dust emission all over the world.Once launched into the atmosphere,Asian dust is then transported to a distal accumulation center,e.g.the North Pacific Ocean via high-altitude westerly winds,becoming an important component in north Pacific sediments.The aeolian deposits in the North Pacific Ocean(NPO) serve as important archives for the paleoenvironmental change in the arid Asian interior,helping to better understand the possible role of the marine biological pump played in the onset of iNHG.This work extracts operationally defined aeolian dust" (ODED) from the sediments recovered at Ocean Drilling Program (ODP) site 1208 (36°07.6'N,158012.1 'E) on the Shatsky Rise in NPO spanning the Pliocene-Pleistocene climate transition.Coring at site 1208 drilled a total of 392.3 m (meters below the sea floor),of which the section between 0.0 and 328.15 m is of Cenozoic age and is characterized by rhythmically alternating intervals of nannofossil ooze/chalk and nannofossil clay/claystone with diatoms and radiolarians that are punctuated by occasional volcanic ash layers.This work collected eight-nine samples continuously every ca.10 cm from 121.3 m to 130.1 m.The chronologic framework of the high-resolution samples has been developed by correlating the benthic-foraminiferal deltaI8O at site 1208 to the global delta~(18)O stack (LR04),allowing the samples in this study have a time interval of 2.62 Ma and 2.85 Ma with roughly one sample every 2500 years.The resulting ODED flux,shows a rapid increase since about 2.73 Ma,concurrent with the increase of the changes in productivity,cooling of the sea surface and the iNHG,implying that biological pump hypothesis is possibly a plausible mechanism for triggering the iNHG.This work also studied the source change of Asian dust archived in site 1208 sediments by measuring the Nd and Sr isotopes of ODED fraction.The results show that the Asian dust archived in site 1208 sediments is mainly derived from Taklimakan Desert throughout the studied time interval.The higher-amplitude fluctuations of Nd and Sr isotopes from 2.73 Ma to 2.85 Ma are attributable to the higher contributions of volcanic ash as a result of the relatively low dust flux and/or the deposition of Gobi dust.The westerly wind might be the main agent to transport the Gobi dust during this interval,as it possibly located in the relatively northern position during the late Pliocene.The position of westerly wind might have moved southward since 2.73 Ma associated with the development of iNHG,mainly transporting Taklimakan dust to the North Pacific Ocean,which resulted in the lower-amplitude fluctuations of Nd and Sr isotopes.It is worthy to note that the more radiogenic Nd isotope and less radiogenic Sr isotope between 2.72 Ma and 2.70 Ma,was probably caused by the abrupt increase of volcanic ash.