Congratulations for Jody Webster

Excellent news from Jody in Hawaii IODP project - a multi-million international project.

Project summary

Our understanding of the links and mechanisms that control eustatic sea-level and global climate changes has been
significantly hampered by a lack of appropriate fossil coral records over the last 500 kyr - particularly into and out
of the glacial periods. We propose to address this problem directly by drilling a unique succession of drowned coral
reefs around Hawaii now at -134 to -1155 m. Abundant observational and numerical modeling data indicate that the
internal stratigraphy and tops of these reefs are highly sensitive to sea-level and climate changes, thereby providing
a firm template with which to conduct these operations. As a direct result of Hawaii’s rapid (2.5-2.6/kyr) but nearly
constant subsidence, a thick (100-200 m) expanded sequence of shallow coral reef dominated facies is preserved
within the reefs. These reefs span important periods in Earth climate history, either not available or highly
condensed on stable (Great Barrier Reef, Tahiti) and uplifted margins (Papua New Guinea, Barbados) due to a lack
of accommodation space and/or unfavorable shelf morphology. Specifically, these data show that the reefs grew
(for ~90-100 kyrs, albeit episodically) into, during and out of the majority of the last five to six glacial cycles.
Therefore, scientific drilling through these reefs will generate a new record of sea-level and associated climate
variability during several controversial and poorly understood periods over the last 500 kyr. The project has four
major objectives. First, to constrain the timing, rate, and amplitude of sea-level variability over the last 500 kyr
allowing a definitive test of Milankovitch climate theory and an assessment of controversial abrupt sea level events
(meltwater pulses) that occur on suborbital frequencies associated with events occurring in the extra-tropics (i.e.
Dansgaard/Oeschger ice core temperature Events, and related Heinrich ice rafted debris Events in N. Atlantic
sediment cores). Second, to investigate processes that determine changes in mean climate and high-frequency
(seasonal-interannual) climate variability using high-resolution coral proxy data from times with different climate
forcing boundary conditions (e.g. ice sheet size, pCO2, solar forcing) over the last 500 kyr. Third, to determine the
response of coral reef systems to abrupt sea-level and climate changes, test sedimentary models of reef evolution as
well as ecologic theories of coral reef resilience and to establish the role of microbial communities in reef building.
And fourth, to refine the variation through space and time of the subsidence of Hawaii and contribute to
understanding the volcanic evolution of the island.