SOURCES AND INVENTORIES OF BIOACTIVE TRACE ELEMENTS ALONG THE INDONESIAN THROUGHFLOW

The Indonesian Throughflow (ITF) travels through southeast island Asia from the equatorial Pacific Ocean to the Indian Ocean, with the potential to become enriched in bioactive trace elements. To determine the distributions and inventories of trace metals in this region, as part of the BLOOFINZ-Indian Ocean expedition (January-March 2022), uncontaminated samples of dissolved and particulate trace elements were collected from the surface waters (~2 m) using a towed “fish” sampling system and from the upper ocean (30-1000 m) using Teflon-coated Niskin-X bottles. In addition, aerosol (3-4 day integrations) and episodic rain samples were collected to determine the atmospheric input of trace metals to the surface ocean, and sediment trap samples (3-4 day integrations) were collected using acid-washed tubes filled with low-trace metal brine to estimate the settling flux of these same elements at four depths from the mixed layer through the nutricline (~440 m). Our presentation will summarize the ongoing analyses and interpretation of these data, with the ultimate goal of quantifying inputs from atmospheric and lateral sources, water column export fluxes, and the "nutritional value" (i.e, chemical composition) of the ITF before it enters the Indian Ocean.

Presentation Preference: Either

Primary Presenter: Peter Morton, Texas A&M University (pete.morton@tamu.edu)

Authors:

Peter Morton, Texas A&M University  (pete.morton@tamu.edu)

Thomas Kelly, University of Alaska-Fairbanks  (tbkelly@alaska.edu)

Robert Lampe, University of California-San Diego  (rlampe@ucsd.edu)