Ocean-Atmosphere Dynamics in the Indo-Pacific Warm Pool Region during the Past 8,500 Years

• Main Authors: M. K. Gagan, L. K. Ayliffe, W. S. Hantoro, E. J. Hendy, M. T. Mcculloch, H. V. Mcgregor, H. Scott-gagan, C. D. Woodroffe
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Greenland; Pacific; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.519.1480

Seasonally resolved palaeoclimate data are important for reconstructing dynamic changes in tropical climate systems and for understanding the processes controlling climate change. We are in the process of developing a multi-proxy approach (δ18O, Sr/Ca, U/Ca, δ13C, ∆14C) to coral-based palaeoclimatology that is yielding records of climatic processes over the last 8,500 years. The following mini-abstracts contain recent results pertinent to our understanding of the Hadley Circulation. Ocean-atmosphere Interactions and Abrupt Cooling in the Tropics 8,000 Years Ago Establishing the relative timing and magnitude of climate change in the tropics and high latitudes provides a means for evaluating the role of the tropics in global climate change. The largest abrupt climate change in the Holocene occurred between 8,400 and 8,000 calendar years ago, when the temperature dropped by 4-8°C in central Greenland and 1.5-3°C around the North Atlantic region. We collected cores from a sequence of well-preserved Porites corals within a rapidly uplifted palaeo-reef in Alor, Indonesia, with 230Th ages spanning 8,400 to 7,600 calendar years before present. Measurements of coral Sr/Ca and δ18O have yielded a semi-continuous record (310 years) showing SSTs essentially the same as today from 8,400 to 7,600 years ago. However