Radiogenic isotopic compositions of low concentration dust and aerosol from the GISP2 ice core

We have produced a record of radiogenic isotope compositions of particulate and soluble dust fractions from the GISP2 ice core, from basal ice to the surface. For each respective dust fraction we measured Sr and Nd isotope values to constrain the provenance of mineral dust and sea salt aerosol transported to the Greenland Ice Sheet. We have produced high-precision measurements of ε_Nd values on sub-ng quantities of Nd in ice core samples via TIMS with 10¹³ ohm resistors. The range of measured ε_Nd values of soluble material (− 12.9 ± 2.6 to − 7.3 ± 0.9) is interpreted to represent sea salt aerosol based on Sr isotope compositions that resemble seawater values (0.711007 ± 0.000030 to 0.709416 ± 0.000072). Therefore, the ε_Nd potentially provides important insights to the atmospheric circulation patterns at high latitudes at least through MIS 5. We compare ε_Nd values of surface seawater from ocean basins and deltas at high latitudes to alternating relatively radiogenic and unradiogenic ε_Nd at GISP2. We suggest these changes represent transitions between a climate system dominated by enhanced and persistent Arctic Oscillation positive anomalies (as determined from sea level and ocean bottom pressure measurements), and a state representative of modern atmospheric circulation, which typically exhibits either negative anomalies or none altogether.