Constraining Temporal Movement of the ITCZ in the Eastern Equatorial Pacific Using Radiogenic Isotopes

Texas A&M Research Foundation, College Station TX

Investigators

Abstract

Dust levels in the atmosphere have important potential effects on climate, including impacts on the Earth's radiative balance and on marine primary productivity, and thus atmospheric CO2, via "fertilization" of surface waters. Information about changes in dust provenance and flux is critical to ground truth atmospheric circulation models, which are are used to investigate the role that dust has on feedbacks which connect continental conditions and global climate. This research, conducted by scientists at Texas A & M University, investigates dust provenance changes in the eastern equatorial Pacific during the late Quaternary. The researchers will perform a temporal study along a transect of sediment cores crossing the equator, as well as a spatial study of modern sediments from a wide area of the eastern equatorial Pacific, analyzing the radiogenic isotope and trace element geochemistry of the dust fraction. In addition, they will determine radiogenic isotope signatures of various end members samples representing the potential dust sources to the Eastern Equatorial Pacific (China, NW South America, SW North America, Australia, northern Africa). This paleo-provenance study will lead to better understanding of the large-scale meridional atmospheric circulation variability of the tropics, which in turn can shed light of past climate forcing mechanisms. Funding supports a PhD student and provides opportunities for undergraduate involvement in research. Results will be incorporated into courses taught by the lead investigator.