Expedition Science Goals
In February of 2010, Prof. Julian Sachs and first year graduate student Nemiah Ladd traveled to the Republic of Nauru in hopes of coring Badua Lagoon, a brackish pond on the smallest island nation in the world.  Due to a series of setbacks and changing conditions, the decision was made to return to Brisbane, Australia, where the two collected a series of mangrove leaves, surface sediment, and water at various salinities along the Brisbane River and its tributaries.
About the Trip
The purpose of this sampling effort was twofold. A component of the laboratory analyses at our University of Washington lab will be directed towards refining understanding of the relationship between salinity, water D/H and the D/H of molecules synthesized by mangroves. Ultimately, this salinity callibration could lead to the development of a new paleoclimate proxy, with broad applications throughout the tropics and subtropics around the world.  The larger goal of this project is to provide another line of evidence to support Prof. Sach’s hypothesis that the position of the Intertropical Convergence Zone (ITCZ) has shifted significantly over the past several thousand years.  Developing a method to use hydrogen isotopes of molecules derived from mangroves should open up a number of new sits for climate reconstructions that will enhance our understanding of climate history of the tropical Pacific.